[PATCH v2 0/3] watchdog: K3: Add RTI watchdog support

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[PATCH v2 0/3] watchdog: K3: Add RTI watchdog support

Jan Kiszka
This brings watchdog support for the TI K3 SoCs, derived from the Linux
kernel, augmented with firmware loading as needed on the AM65x.

Tested on the AM65x EVM and the IOT2050 (also AM65x-based, upstream
support will be posted soon).

Changes in v2:
 - keep watchdog powered when handing over to Linux
 - drop unneeded explicit power-on
 - account for RTI firmware locking the power domain

Jan

Jan Kiszka (3):
  watchdog: Add support for K3 RTI watchdog
  watchdog: rti_wdt: Add support for loading firmware
  arm: dts: k3: Add RTI watchdogs

 arch/arm/dts/k3-am65-mcu.dtsi   |   9 ++
 arch/arm/dts/k3-j721e-main.dtsi |  18 ++++
 drivers/watchdog/Kconfig        |  27 ++++++
 drivers/watchdog/Makefile       |   4 +
 drivers/watchdog/rti_wdt.c      | 147 ++++++++++++++++++++++++++++++++
 drivers/watchdog/rti_wdt_fw.S   |  20 +++++
 6 files changed, 225 insertions(+)
 create mode 100644 drivers/watchdog/rti_wdt.c
 create mode 100644 drivers/watchdog/rti_wdt_fw.S

--
2.26.2

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[PATCH v2 1/3] watchdog: Add support for K3 RTI watchdog

Jan Kiszka
From: Jan Kiszka <[hidden email]>

This is based on the Linux kernel driver for the RTI watchdog.

To actually reset the system on an AM65x, it requires firmware running
on the R5 that accepts the NMI and issues the actual system reset via
TISCI. Kind of an iTCO, except that this watchdog hardware has support
for no-way-out, and only for that.

On the J721E, reset works without extra firmware help when routing the
RTI interrupt via the ESM.

Signed-off-by: Jan Kiszka <[hidden email]>
---
 drivers/watchdog/Kconfig   |   7 +++
 drivers/watchdog/Makefile  |   1 +
 drivers/watchdog/rti_wdt.c | 123 +++++++++++++++++++++++++++++++++++++
 3 files changed, 131 insertions(+)
 create mode 100644 drivers/watchdog/rti_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index bf06180cdd..ee99bd2af1 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -155,6 +155,13 @@ config WDT_ORION
   Select this to enable Orion watchdog timer, which can be found on some
   Marvell Armada chips.
 
+config WDT_K3_RTI
+ bool "Texas Instruments K3 RTI watchdog"
+ depends on WDT && ARCH_K3
+ help
+  Say Y here if you want to include support for the K3 watchdog
+  timer (RTI module) available in the K3 generation of processors.
+
 config WDT_SANDBOX
  bool "Enable Watchdog Timer support for Sandbox"
  depends on SANDBOX && WDT
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 519bbd3a40..16bdbf4970 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o
 obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
 obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
 obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
+obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
 obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
 obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
 obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
new file mode 100644
index 0000000000..ebe29c7409
--- /dev/null
+++ b/drivers/watchdog/rti_wdt.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) Siemens AG, 2020
+ *
+ * Authors:
+ *   Jan Kiszka <[hidden email]>
+ *
+ * Derived from linux/drivers/watchdog/rti_wdt.c
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <power-domain.h>
+#include <wdt.h>
+#include <asm/io.h>
+
+/* Timer register set definition */
+#define RTIDWDCTRL 0x90
+#define RTIDWDPRLD 0x94
+#define RTIWDSTATUS 0x98
+#define RTIWDKEY 0x9c
+#define RTIDWDCNTR 0xa0
+#define RTIWWDRXCTRL 0xa4
+#define RTIWWDSIZECTRL 0xa8
+
+#define RTIWWDRX_NMI 0xa
+
+#define RTIWWDSIZE_50P 0x50
+
+#define WDENABLE_KEY 0xa98559da
+
+#define WDKEY_SEQ0 0xe51a
+#define WDKEY_SEQ1 0xa35c
+
+#define WDT_PRELOAD_SHIFT 13
+
+#define WDT_PRELOAD_MAX 0xfff
+
+struct rti_wdt_priv {
+ phys_addr_t regs;
+ unsigned int clk_khz;
+};
+
+static int rti_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
+{
+ struct rti_wdt_priv *priv = dev_get_priv(dev);
+ u32 timer_margin;
+ int ret;
+
+ if (readl(priv->regs + RTIDWDCTRL) == WDENABLE_KEY)
+ return -EBUSY;
+
+ timer_margin = timeout_ms * priv->clk_khz / 1000;
+ timer_margin >>= WDT_PRELOAD_SHIFT;
+ if (timer_margin > WDT_PRELOAD_MAX)
+ timer_margin = WDT_PRELOAD_MAX;
+
+ writel(timer_margin, priv->regs + RTIDWDPRLD);
+ writel(RTIWWDRX_NMI, priv->regs + RTIWWDRXCTRL);
+ writel(RTIWWDSIZE_50P, priv->regs + RTIWWDSIZECTRL);
+
+ readl(priv->regs + RTIWWDSIZECTRL);
+
+ writel(WDENABLE_KEY, priv->regs + RTIDWDCTRL);
+
+ return 0;
+}
+
+static int rti_wdt_reset(struct udevice *dev)
+{
+ struct rti_wdt_priv *priv = dev_get_priv(dev);
+ u32 prld;
+
+ /* Make sure we do not reset too early */
+ prld = readl(priv->regs + RTIDWDPRLD) << WDT_PRELOAD_SHIFT;
+ if (readl(priv->regs + RTIDWDCNTR) >= prld / 2)
+ return -EPERM;
+
+ writel(WDKEY_SEQ0, priv->regs + RTIWDKEY);
+ writel(WDKEY_SEQ1, priv->regs + RTIWDKEY);
+
+ return 0;
+}
+
+static int rti_wdt_probe(struct udevice *dev)
+{
+ struct rti_wdt_priv *priv = dev_get_priv(dev);
+ struct clk clk;
+ int ret;
+
+ priv->regs = devfdt_get_addr(dev);
+ if (!priv->regs)
+ return -EINVAL;
+
+ ret = clk_get_by_index(dev, 0, &clk);
+ if (ret)
+ return ret;
+
+ priv->clk_khz = clk_get_rate(&clk);
+
+ return 0;
+}
+
+static const struct wdt_ops rti_wdt_ops = {
+ .start = rti_wdt_start,
+ .reset = rti_wdt_reset,
+};
+
+static const struct udevice_id rti_wdt_ids[] = {
+ { .compatible = "ti,j7-rti-wdt" },
+ { }
+};
+
+U_BOOT_DRIVER(rti_wdt) = {
+ .name = "rti_wdt",
+ .id = UCLASS_WDT,
+ .of_match = rti_wdt_ids,
+ .ops = &rti_wdt_ops,
+ .probe = rti_wdt_probe,
+ .priv_auto_alloc_size = sizeof(struct rti_wdt_priv),
+ .flags = DM_FLAG_REMOVE_WITH_PD_ON,
+};
--
2.26.2

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[PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
In reply to this post by Jan Kiszka
From: Jan Kiszka <[hidden email]>

To avoid the need of extra boot scripting on AM65x for loading a
watchdog firmware, add the required rproc init and loading logic for the
first R5F core to the watchdog start handler. The firmware itself is
embedded into U-Boot binary.

One possible firmware source is https://github.com/siemens/k3-rti-wdt.

Signed-off-by: Jan Kiszka <[hidden email]>
---
 drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
 drivers/watchdog/Makefile     |  3 +++
 drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
 drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
 4 files changed, 67 insertions(+)
 create mode 100644 drivers/watchdog/rti_wdt_fw.S

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index ee99bd2af1..fd6ab9a85b 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -162,6 +162,26 @@ config WDT_K3_RTI
   Say Y here if you want to include support for the K3 watchdog
   timer (RTI module) available in the K3 generation of processors.
 
+if WDT_K3_RTI
+
+config WDT_K3_RTI_LOAD_FW
+ bool "Load watchdog firmware"
+ depends on REMOTEPROC
+ help
+  Automatically load the specified firmware image into the MCU R5F
+  core 0. On the AM65x, this firmware is supposed to handle the expiry
+  of the watchdog timer, typically by resetting the system.
+
+config WDT_K3_RTI_FW_FILE
+ string "Watchdog firmware image file"
+ default "k3-rti-wdt.fw"
+ depends on WDT_K3_RTI_LOAD_FW
+ help
+  Firmware image to be embedded into U-Boot and loaded on watchdog
+  start.
+
+endif
+
 config WDT_SANDBOX
  bool "Enable Watchdog Timer support for Sandbox"
  depends on SANDBOX && WDT
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 16bdbf4970..bf58684875 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
 obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
 obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
 obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
+obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
 obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
 obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
 obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
 obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
+
+$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
index ebe29c7409..38e82a6b6b 100644
--- a/drivers/watchdog/rti_wdt.c
+++ b/drivers/watchdog/rti_wdt.c
@@ -14,6 +14,7 @@
 #include <power-domain.h>
 #include <wdt.h>
 #include <asm/io.h>
+#include <remoteproc.h>
 
 /* Timer register set definition */
 #define RTIDWDCTRL 0x90
@@ -37,11 +38,16 @@
 
 #define WDT_PRELOAD_MAX 0xfff
 
+#define RTI_PROC_ID 0
+
 struct rti_wdt_priv {
  phys_addr_t regs;
  unsigned int clk_khz;
 };
 
+extern const u32 rti_wdt_fw[];
+extern const int rti_wdt_fw_size;
+
 static int rti_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
 {
  struct rti_wdt_priv *priv = dev_get_priv(dev);
@@ -51,6 +57,24 @@ static int rti_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
  if (readl(priv->regs + RTIDWDCTRL) == WDENABLE_KEY)
  return -EBUSY;
 
+#ifdef CONFIG_WDT_K3_RTI_LOAD_FW
+ ret = rproc_dev_init(RTI_PROC_ID);
+ if (ret) {
+    fw_error:
+ dev_err(dev, "Failed to load watchdog firmware into remote processor %d\n",
+ RTI_PROC_ID);
+ return ret;
+ }
+
+ ret = rproc_load(RTI_PROC_ID, (ulong)rti_wdt_fw, rti_wdt_fw_size);
+ if (ret)
+ goto fw_error;
+
+ ret = rproc_start(RTI_PROC_ID);
+ if (ret)
+ goto fw_error;
+#endif
+
  timer_margin = timeout_ms * priv->clk_khz / 1000;
  timer_margin >>= WDT_PRELOAD_SHIFT;
  if (timer_margin > WDT_PRELOAD_MAX)
diff --git a/drivers/watchdog/rti_wdt_fw.S b/drivers/watchdog/rti_wdt_fw.S
new file mode 100644
index 0000000000..78d99ff9f2
--- /dev/null
+++ b/drivers/watchdog/rti_wdt_fw.S
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) Siemens AG, 2020
+ *
+ * Authors:
+ *   Jan Kiszka <[hidden email]>
+ */
+
+.section .rodata
+
+.global rti_wdt_fw
+.global rti_wdt_fw_size
+
+rti_wdt_fw:
+.align 4
+.incbin CONFIG_WDT_K3_RTI_FW_FILE
+rti_wdt_fw_end:
+
+rti_wdt_fw_size:
+.int rti_wdt_fw_end - rti_wdt_fw
--
2.26.2

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[PATCH v2 3/3] arm: dts: k3: Add RTI watchdogs

Jan Kiszka
In reply to this post by Jan Kiszka
From: Jan Kiszka <[hidden email]>

Add DT entries for main domain watchdog0 and 1 instances on the J721e
well as RTI1-based watchdog on the AM65x. RTI0 does not work for this
purpose on the AM65x, so leave it out.

On AM65x, we mark the power-domain as shared because RTI firmware such
as https://github.com/siemens/k3-rti-wdt may request it as well in order
to prevent accidental shutdown of the watchdog.

Signed-off-by: Jan Kiszka <[hidden email]>
---
 arch/arm/dts/k3-am65-mcu.dtsi   |  9 +++++++++
 arch/arm/dts/k3-j721e-main.dtsi | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/arch/arm/dts/k3-am65-mcu.dtsi b/arch/arm/dts/k3-am65-mcu.dtsi
index bc9a87210d..6498dcdae4 100644
--- a/arch/arm/dts/k3-am65-mcu.dtsi
+++ b/arch/arm/dts/k3-am65-mcu.dtsi
@@ -102,4 +102,13 @@
  #size-cells = <0>;
  };
  };
+
+ mcu_rti1: rti@40610000 {
+ compatible = "ti,j7-rti-wdt";
+ reg = <0x0 0x40610000 0x0 0x100>;
+ clocks = <&k3_clks 135 0>;
+ power-domains = <&k3_pds 135 TI_SCI_PD_SHARED>;
+ assigned-clocks = <&k3_clks 135 0>;
+ assigned-clock-parents = <&k3_clks 135 4>;
+ };
 };
diff --git a/arch/arm/dts/k3-j721e-main.dtsi b/arch/arm/dts/k3-j721e-main.dtsi
index 1433932e7f..a285b1afa8 100644
--- a/arch/arm/dts/k3-j721e-main.dtsi
+++ b/arch/arm/dts/k3-j721e-main.dtsi
@@ -543,4 +543,22 @@
  clocks = <&k3_clks 193 0>;
  power-domains = <&k3_pds 193 TI_SCI_PD_EXCLUSIVE>;
  };
+
+ watchdog0: watchdog@2200000 {
+ compatible = "ti,j7-rti-wdt";
+ reg = <0x0 0x2200000 0x0 0x100>;
+ clocks = <&k3_clks 252 1>;
+ power-domains = <&k3_pds 252 TI_SCI_PD_EXCLUSIVE>;
+ assigned-clocks = <&k3_clks 252 1>;
+ assigned-clock-parents = <&k3_clks 252 5>;
+ };
+
+ watchdog1: watchdog@2210000 {
+ compatible = "ti,j7-rti-wdt";
+ reg = <0x0 0x2210000 0x0 0x100>;
+ clocks = <&k3_clks 253 1>;
+ power-domains = <&k3_pds 253 TI_SCI_PD_EXCLUSIVE>;
+ assigned-clocks = <&k3_clks 253 1>;
+ assigned-clock-parents = <&k3_clks 253 5>;
+ };
 };
--
2.26.2

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Re: [PATCH v2 1/3] watchdog: Add support for K3 RTI watchdog

Lokesh Vutla
In reply to this post by Jan Kiszka


On 23/06/20 4:45 pm, Jan Kiszka wrote:

> From: Jan Kiszka <[hidden email]>
>
> This is based on the Linux kernel driver for the RTI watchdog.
>
> To actually reset the system on an AM65x, it requires firmware running
> on the R5 that accepts the NMI and issues the actual system reset via
> TISCI. Kind of an iTCO, except that this watchdog hardware has support
> for no-way-out, and only for that.
>
> On the J721E, reset works without extra firmware help when routing the
> RTI interrupt via the ESM.
>
> Signed-off-by: Jan Kiszka <[hidden email]>
> ---
>  drivers/watchdog/Kconfig   |   7 +++
>  drivers/watchdog/Makefile  |   1 +
>  drivers/watchdog/rti_wdt.c | 123 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 131 insertions(+)
>  create mode 100644 drivers/watchdog/rti_wdt.c
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index bf06180cdd..ee99bd2af1 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -155,6 +155,13 @@ config WDT_ORION
>    Select this to enable Orion watchdog timer, which can be found on some
>    Marvell Armada chips.
>  
> +config WDT_K3_RTI
> + bool "Texas Instruments K3 RTI watchdog"
> + depends on WDT && ARCH_K3
> + help
> +  Say Y here if you want to include support for the K3 watchdog
> +  timer (RTI module) available in the K3 generation of processors.
> +
>  config WDT_SANDBOX
>   bool "Enable Watchdog Timer support for Sandbox"
>   depends on SANDBOX && WDT
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 519bbd3a40..16bdbf4970 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o
>  obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>  obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>  obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
> +obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>  obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>  obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>  obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
> new file mode 100644
> index 0000000000..ebe29c7409
> --- /dev/null
> +++ b/drivers/watchdog/rti_wdt.c
> @@ -0,0 +1,123 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) Siemens AG, 2020
> + *
> + * Authors:
> + *   Jan Kiszka <[hidden email]>
> + *
> + * Derived from linux/drivers/watchdog/rti_wdt.c
> + */
> +
> +#include <common.h>
> +#include <clk.h>
> +#include <dm.h>
> +#include <power-domain.h>
> +#include <wdt.h>
> +#include <asm/io.h>
> +
> +/* Timer register set definition */
> +#define RTIDWDCTRL 0x90
> +#define RTIDWDPRLD 0x94
> +#define RTIWDSTATUS 0x98
> +#define RTIWDKEY 0x9c
> +#define RTIDWDCNTR 0xa0
> +#define RTIWWDRXCTRL 0xa4
> +#define RTIWWDSIZECTRL 0xa8
> +
> +#define RTIWWDRX_NMI 0xa
> +
> +#define RTIWWDSIZE_50P 0x50
> +
> +#define WDENABLE_KEY 0xa98559da
> +
> +#define WDKEY_SEQ0 0xe51a
> +#define WDKEY_SEQ1 0xa35c
> +
> +#define WDT_PRELOAD_SHIFT 13
> +
> +#define WDT_PRELOAD_MAX 0xfff
> +
> +struct rti_wdt_priv {
> + phys_addr_t regs;
> + unsigned int clk_khz;
> +};
> +
> +static int rti_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
> +{
> + struct rti_wdt_priv *priv = dev_get_priv(dev);
> + u32 timer_margin;
> + int ret;
> +
> + if (readl(priv->regs + RTIDWDCTRL) == WDENABLE_KEY)
> + return -EBUSY;
> +
> + timer_margin = timeout_ms * priv->clk_khz / 1000;
> + timer_margin >>= WDT_PRELOAD_SHIFT;
> + if (timer_margin > WDT_PRELOAD_MAX)
> + timer_margin = WDT_PRELOAD_MAX;
> +
> + writel(timer_margin, priv->regs + RTIDWDPRLD);
> + writel(RTIWWDRX_NMI, priv->regs + RTIWWDRXCTRL);
> + writel(RTIWWDSIZE_50P, priv->regs + RTIWWDSIZECTRL);
> +
> + readl(priv->regs + RTIWWDSIZECTRL);
> +
> + writel(WDENABLE_KEY, priv->regs + RTIDWDCTRL);

What happens if the watchdog timer expires in U-Boot?

Is the watchdog started from U-Boot command line?

> +
> + return 0;
> +}
> +
> +static int rti_wdt_reset(struct udevice *dev)
> +{
> + struct rti_wdt_priv *priv = dev_get_priv(dev);
> + u32 prld;
> +
> + /* Make sure we do not reset too early */
> + prld = readl(priv->regs + RTIDWDPRLD) << WDT_PRELOAD_SHIFT;
> + if (readl(priv->regs + RTIDWDCNTR) >= prld / 2)
> + return -EPERM;
> +
> + writel(WDKEY_SEQ0, priv->regs + RTIWDKEY);
> + writel(WDKEY_SEQ1, priv->regs + RTIWDKEY);
> +
> + return 0;
> +}
> +
> +static int rti_wdt_probe(struct udevice *dev)
> +{
> + struct rti_wdt_priv *priv = dev_get_priv(dev);
> + struct clk clk;
> + int ret;
> +
> + priv->regs = devfdt_get_addr(dev);
> + if (!priv->regs)
> + return -EINVAL;
> +
> + ret = clk_get_by_index(dev, 0, &clk);
> + if (ret)
> + return ret;
> +
> + priv->clk_khz = clk_get_rate(&clk);
> +
> + return 0;
> +}
> +
> +static const struct wdt_ops rti_wdt_ops = {
> + .start = rti_wdt_start,
> + .reset = rti_wdt_reset,
> +};
> +
> +static const struct udevice_id rti_wdt_ids[] = {
> + { .compatible = "ti,j7-rti-wdt" },

Is this compatible matching with Kernel's compatible?

Thanks and regards,
Lokesh

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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Lokesh Vutla
In reply to this post by Jan Kiszka


On 23/06/20 4:45 pm, Jan Kiszka wrote:

> From: Jan Kiszka <[hidden email]>
>
> To avoid the need of extra boot scripting on AM65x for loading a
> watchdog firmware, add the required rproc init and loading logic for the
> first R5F core to the watchdog start handler. The firmware itself is
> embedded into U-Boot binary.
>
> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>
> Signed-off-by: Jan Kiszka <[hidden email]>
> ---
>  drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>  drivers/watchdog/Makefile     |  3 +++
>  drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>  drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>  4 files changed, 67 insertions(+)
>  create mode 100644 drivers/watchdog/rti_wdt_fw.S
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index ee99bd2af1..fd6ab9a85b 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>    Say Y here if you want to include support for the K3 watchdog
>    timer (RTI module) available in the K3 generation of processors.
>  
> +if WDT_K3_RTI
> +
> +config WDT_K3_RTI_LOAD_FW
> + bool "Load watchdog firmware"
> + depends on REMOTEPROC
> + help
> +  Automatically load the specified firmware image into the MCU R5F
> +  core 0. On the AM65x, this firmware is supposed to handle the expiry
> +  of the watchdog timer, typically by resetting the system.
> +
> +config WDT_K3_RTI_FW_FILE
> + string "Watchdog firmware image file"
> + default "k3-rti-wdt.fw"
> + depends on WDT_K3_RTI_LOAD_FW
> + help
> +  Firmware image to be embedded into U-Boot and loaded on watchdog
> +  start.
> +
> +endif
> +
>  config WDT_SANDBOX
>   bool "Enable Watchdog Timer support for Sandbox"
>   depends on SANDBOX && WDT
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 16bdbf4970..bf58684875 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>  obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>  obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>  obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>  obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>  obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>  obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>  obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
> +
> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
> index ebe29c7409..38e82a6b6b 100644
> --- a/drivers/watchdog/rti_wdt.c
> +++ b/drivers/watchdog/rti_wdt.c
> @@ -14,6 +14,7 @@
>  #include <power-domain.h>
>  #include <wdt.h>
>  #include <asm/io.h>
> +#include <remoteproc.h>
>  
>  /* Timer register set definition */
>  #define RTIDWDCTRL 0x90
> @@ -37,11 +38,16 @@
>  
>  #define WDT_PRELOAD_MAX 0xfff
>  
> +#define RTI_PROC_ID 0

Can we get the rproc id from DT?

> +
>  struct rti_wdt_priv {
>   phys_addr_t regs;
>   unsigned int clk_khz;
>  };
>  
> +extern const u32 rti_wdt_fw[];
> +extern const int rti_wdt_fw_size;

FIT is the preferred way of packing images in U-Boot. Can you try using it?

Thanks and regards,
Lokesh

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Re: [PATCH v2 1/3] watchdog: Add support for K3 RTI watchdog

Jan Kiszka
In reply to this post by Lokesh Vutla
On 23.06.20 13:47, Lokesh Vutla wrote:

>
>
> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>> From: Jan Kiszka <[hidden email]>
>>
>> This is based on the Linux kernel driver for the RTI watchdog.
>>
>> To actually reset the system on an AM65x, it requires firmware running
>> on the R5 that accepts the NMI and issues the actual system reset via
>> TISCI. Kind of an iTCO, except that this watchdog hardware has support
>> for no-way-out, and only for that.
>>
>> On the J721E, reset works without extra firmware help when routing the
>> RTI interrupt via the ESM.
>>
>> Signed-off-by: Jan Kiszka <[hidden email]>
>> ---
>>   drivers/watchdog/Kconfig   |   7 +++
>>   drivers/watchdog/Makefile  |   1 +
>>   drivers/watchdog/rti_wdt.c | 123 +++++++++++++++++++++++++++++++++++++
>>   3 files changed, 131 insertions(+)
>>   create mode 100644 drivers/watchdog/rti_wdt.c
>>
>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>> index bf06180cdd..ee99bd2af1 100644
>> --- a/drivers/watchdog/Kconfig
>> +++ b/drivers/watchdog/Kconfig
>> @@ -155,6 +155,13 @@ config WDT_ORION
>>    Select this to enable Orion watchdog timer, which can be found on some
>>    Marvell Armada chips.
>>  
>> +config WDT_K3_RTI
>> + bool "Texas Instruments K3 RTI watchdog"
>> + depends on WDT && ARCH_K3
>> + help
>> +  Say Y here if you want to include support for the K3 watchdog
>> +  timer (RTI module) available in the K3 generation of processors.
>> +
>>   config WDT_SANDBOX
>>   bool "Enable Watchdog Timer support for Sandbox"
>>   depends on SANDBOX && WDT
>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>> index 519bbd3a40..16bdbf4970 100644
>> --- a/drivers/watchdog/Makefile
>> +++ b/drivers/watchdog/Makefile
>> @@ -27,6 +27,7 @@ obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o
>>   obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>   obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>   obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>> +obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>   obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>   obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>   obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>> new file mode 100644
>> index 0000000000..ebe29c7409
>> --- /dev/null
>> +++ b/drivers/watchdog/rti_wdt.c
>> @@ -0,0 +1,123 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * Copyright (c) Siemens AG, 2020
>> + *
>> + * Authors:
>> + *   Jan Kiszka <[hidden email]>
>> + *
>> + * Derived from linux/drivers/watchdog/rti_wdt.c
>> + */
>> +
>> +#include <common.h>
>> +#include <clk.h>
>> +#include <dm.h>
>> +#include <power-domain.h>
>> +#include <wdt.h>
>> +#include <asm/io.h>
>> +
>> +/* Timer register set definition */
>> +#define RTIDWDCTRL 0x90
>> +#define RTIDWDPRLD 0x94
>> +#define RTIWDSTATUS 0x98
>> +#define RTIWDKEY 0x9c
>> +#define RTIDWDCNTR 0xa0
>> +#define RTIWWDRXCTRL 0xa4
>> +#define RTIWWDSIZECTRL 0xa8
>> +
>> +#define RTIWWDRX_NMI 0xa
>> +
>> +#define RTIWWDSIZE_50P 0x50
>> +
>> +#define WDENABLE_KEY 0xa98559da
>> +
>> +#define WDKEY_SEQ0 0xe51a
>> +#define WDKEY_SEQ1 0xa35c
>> +
>> +#define WDT_PRELOAD_SHIFT 13
>> +
>> +#define WDT_PRELOAD_MAX 0xfff
>> +
>> +struct rti_wdt_priv {
>> + phys_addr_t regs;
>> + unsigned int clk_khz;
>> +};
>> +
>> +static int rti_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
>> +{
>> + struct rti_wdt_priv *priv = dev_get_priv(dev);
>> + u32 timer_margin;
>> + int ret;
>> +
>> + if (readl(priv->regs + RTIDWDCTRL) == WDENABLE_KEY)
>> + return -EBUSY;
>> +
>> + timer_margin = timeout_ms * priv->clk_khz / 1000;
>> + timer_margin >>= WDT_PRELOAD_SHIFT;
>> + if (timer_margin > WDT_PRELOAD_MAX)
>> + timer_margin = WDT_PRELOAD_MAX;
>> +
>> + writel(timer_margin, priv->regs + RTIDWDPRLD);
>> + writel(RTIWWDRX_NMI, priv->regs + RTIWWDRXCTRL);
>> + writel(RTIWWDSIZE_50P, priv->regs + RTIWWDSIZECTRL);
>> +
>> + readl(priv->regs + RTIWWDSIZECTRL);
>> +
>> + writel(WDENABLE_KEY, priv->regs + RTIDWDCTRL);
>
> What happens if the watchdog timer expires in U-Boot?
>

Then we reset. You can feed the watchdog also from U-Boot, just enable
CONFIG_WATCHDOG.

> Is the watchdog started from U-Boot command line?
>

U-Boot automatically starts the first watchdog it finds. I didn't find a
switch to disable that. If you have multiple watchdogs, you can start
others also via "wdt".

>> +
>> + return 0;
>> +}
>> +
>> +static int rti_wdt_reset(struct udevice *dev)
>> +{
>> + struct rti_wdt_priv *priv = dev_get_priv(dev);
>> + u32 prld;
>> +
>> + /* Make sure we do not reset too early */
>> + prld = readl(priv->regs + RTIDWDPRLD) << WDT_PRELOAD_SHIFT;
>> + if (readl(priv->regs + RTIDWDCNTR) >= prld / 2)
>> + return -EPERM;
>> +
>> + writel(WDKEY_SEQ0, priv->regs + RTIWDKEY);
>> + writel(WDKEY_SEQ1, priv->regs + RTIWDKEY);
>> +
>> + return 0;
>> +}
>> +
>> +static int rti_wdt_probe(struct udevice *dev)
>> +{
>> + struct rti_wdt_priv *priv = dev_get_priv(dev);
>> + struct clk clk;
>> + int ret;
>> +
>> + priv->regs = devfdt_get_addr(dev);
>> + if (!priv->regs)
>> + return -EINVAL;
>> +
>> + ret = clk_get_by_index(dev, 0, &clk);
>> + if (ret)
>> + return ret;
>> +
>> + priv->clk_khz = clk_get_rate(&clk);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct wdt_ops rti_wdt_ops = {
>> + .start = rti_wdt_start,
>> + .reset = rti_wdt_reset,
>> +};
>> +
>> +static const struct udevice_id rti_wdt_ids[] = {
>> + { .compatible = "ti,j7-rti-wdt" },
>
> Is this compatible matching with Kernel's compatible?
>

Yes.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
In reply to this post by Lokesh Vutla
On 23.06.20 13:50, Lokesh Vutla wrote:

>
>
> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>> From: Jan Kiszka <[hidden email]>
>>
>> To avoid the need of extra boot scripting on AM65x for loading a
>> watchdog firmware, add the required rproc init and loading logic for the
>> first R5F core to the watchdog start handler. The firmware itself is
>> embedded into U-Boot binary.
>>
>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>
>> Signed-off-by: Jan Kiszka <[hidden email]>
>> ---
>>   drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>   drivers/watchdog/Makefile     |  3 +++
>>   drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>   drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>   4 files changed, 67 insertions(+)
>>   create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>
>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>> index ee99bd2af1..fd6ab9a85b 100644
>> --- a/drivers/watchdog/Kconfig
>> +++ b/drivers/watchdog/Kconfig
>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>    Say Y here if you want to include support for the K3 watchdog
>>    timer (RTI module) available in the K3 generation of processors.
>>  
>> +if WDT_K3_RTI
>> +
>> +config WDT_K3_RTI_LOAD_FW
>> + bool "Load watchdog firmware"
>> + depends on REMOTEPROC
>> + help
>> +  Automatically load the specified firmware image into the MCU R5F
>> +  core 0. On the AM65x, this firmware is supposed to handle the expiry
>> +  of the watchdog timer, typically by resetting the system.
>> +
>> +config WDT_K3_RTI_FW_FILE
>> + string "Watchdog firmware image file"
>> + default "k3-rti-wdt.fw"
>> + depends on WDT_K3_RTI_LOAD_FW
>> + help
>> +  Firmware image to be embedded into U-Boot and loaded on watchdog
>> +  start.
>> +
>> +endif
>> +
>>   config WDT_SANDBOX
>>   bool "Enable Watchdog Timer support for Sandbox"
>>   depends on SANDBOX && WDT
>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>> index 16bdbf4970..bf58684875 100644
>> --- a/drivers/watchdog/Makefile
>> +++ b/drivers/watchdog/Makefile
>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>   obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>   obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>   obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>   obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>   obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>   obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>   obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>> +
>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>> index ebe29c7409..38e82a6b6b 100644
>> --- a/drivers/watchdog/rti_wdt.c
>> +++ b/drivers/watchdog/rti_wdt.c
>> @@ -14,6 +14,7 @@
>>   #include <power-domain.h>
>>   #include <wdt.h>
>>   #include <asm/io.h>
>> +#include <remoteproc.h>
>>  
>>   /* Timer register set definition */
>>   #define RTIDWDCTRL 0x90
>> @@ -37,11 +38,16 @@
>>  
>>   #define WDT_PRELOAD_MAX 0xfff
>>  
>> +#define RTI_PROC_ID 0
>
> Can we get the rproc id from DT?

You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.

>
>> +
>>   struct rti_wdt_priv {
>>   phys_addr_t regs;
>>   unsigned int clk_khz;
>>   };
>>  
>> +extern const u32 rti_wdt_fw[];
>> +extern const int rti_wdt_fw_size;
>
> FIT is the preferred way of packing images in U-Boot. Can you try using it?

How does that work? Some example for me?

What benefit would that bring? There are other users of this pattern,
e.g. board/xilinx/zynqmp/pm_cfg_obj.S.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
On 23.06.20 14:37, Jan Kiszka wrote:

> On 23.06.20 13:50, Lokesh Vutla wrote:
>>
>>
>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>> From: Jan Kiszka <[hidden email]>
>>>
>>> To avoid the need of extra boot scripting on AM65x for loading a
>>> watchdog firmware, add the required rproc init and loading logic for the
>>> first R5F core to the watchdog start handler. The firmware itself is
>>> embedded into U-Boot binary.
>>>
>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>
>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>> ---
>>>   drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>   drivers/watchdog/Makefile     |  3 +++
>>>   drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>   drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>   4 files changed, 67 insertions(+)
>>>   create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>
>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>> index ee99bd2af1..fd6ab9a85b 100644
>>> --- a/drivers/watchdog/Kconfig
>>> +++ b/drivers/watchdog/Kconfig
>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>         Say Y here if you want to include support for the K3 watchdog
>>>         timer (RTI module) available in the K3 generation of processors.
>>> +if WDT_K3_RTI
>>> +
>>> +config WDT_K3_RTI_LOAD_FW
>>> +    bool "Load watchdog firmware"
>>> +    depends on REMOTEPROC
>>> +    help
>>> +      Automatically load the specified firmware image into the MCU R5F
>>> +      core 0. On the AM65x, this firmware is supposed to handle the
>>> expiry
>>> +      of the watchdog timer, typically by resetting the system.
>>> +
>>> +config WDT_K3_RTI_FW_FILE
>>> +    string "Watchdog firmware image file"
>>> +    default "k3-rti-wdt.fw"
>>> +    depends on WDT_K3_RTI_LOAD_FW
>>> +    help
>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>> +      start.
>>> +
>>> +endif
>>> +
>>>   config WDT_SANDBOX
>>>       bool "Enable Watchdog Timer support for Sandbox"
>>>       depends on SANDBOX && WDT
>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>> index 16bdbf4970..bf58684875 100644
>>> --- a/drivers/watchdog/Makefile
>>> +++ b/drivers/watchdog/Makefile
>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>   obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>   obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>   obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>   obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>   obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>   obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>   obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>> +
>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f
>>> $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>> index ebe29c7409..38e82a6b6b 100644
>>> --- a/drivers/watchdog/rti_wdt.c
>>> +++ b/drivers/watchdog/rti_wdt.c
>>> @@ -14,6 +14,7 @@
>>>   #include <power-domain.h>
>>>   #include <wdt.h>
>>>   #include <asm/io.h>
>>> +#include <remoteproc.h>
>>>   /* Timer register set definition */
>>>   #define RTIDWDCTRL        0x90
>>> @@ -37,11 +38,16 @@
>>>   #define WDT_PRELOAD_MAX        0xfff
>>> +#define RTI_PROC_ID        0
>>
>> Can we get the rproc id from DT?
>
> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>

I'm now probing for the first instance of "ti,am654-r5f" compatible.
That excludes usage for the J721E for now, but that one is fine without
firmware - provided there is way to prevent power-down for RTI watchdog
otherwise...

>>
>>> +
>>>   struct rti_wdt_priv {
>>>       phys_addr_t regs;
>>>       unsigned int clk_khz;
>>>   };
>>> +extern const u32 rti_wdt_fw[];
>>> +extern const int rti_wdt_fw_size;
>>
>> FIT is the preferred way of packing images in U-Boot. Can you try
>> using it?
>
> How does that work? Some example for me?
>

If you happen to refer to fs-loader: That does not target OSPI, our
primary use case.

> What benefit would that bring? There are other users of this pattern,
> e.g. board/xilinx/zynqmp/pm_cfg_obj.S.
>

The only benefit of an alternative loading mechanism seems to be
handling of larger images from different sources. But that's what I
would tackle via boot scripting and, thus, without this feature. If you
only have a few hundred bytes to embed, like for k3-rti-wdt, you quickly
have a lot of overhead with other approaches.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Lokesh Vutla
+Tom

On 23/06/20 8:11 pm, Jan Kiszka wrote:

> On 23.06.20 14:37, Jan Kiszka wrote:
>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>
>>>
>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>> From: Jan Kiszka <[hidden email]>
>>>>
>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>> embedded into U-Boot binary.
>>>>
>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>
>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>> ---
>>>>   drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>   drivers/watchdog/Makefile     |  3 +++
>>>>   drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>   drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>   4 files changed, 67 insertions(+)
>>>>   create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>
>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>> --- a/drivers/watchdog/Kconfig
>>>> +++ b/drivers/watchdog/Kconfig
>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>         Say Y here if you want to include support for the K3 watchdog
>>>>         timer (RTI module) available in the K3 generation of processors.
>>>> +if WDT_K3_RTI
>>>> +
>>>> +config WDT_K3_RTI_LOAD_FW
>>>> +    bool "Load watchdog firmware"
>>>> +    depends on REMOTEPROC
>>>> +    help
>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>> +      of the watchdog timer, typically by resetting the system.
>>>> +
>>>> +config WDT_K3_RTI_FW_FILE
>>>> +    string "Watchdog firmware image file"
>>>> +    default "k3-rti-wdt.fw"
>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>> +    help
>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>> +      start.
>>>> +
>>>> +endif
>>>> +
>>>>   config WDT_SANDBOX
>>>>       bool "Enable Watchdog Timer support for Sandbox"
>>>>       depends on SANDBOX && WDT
>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>> index 16bdbf4970..bf58684875 100644
>>>> --- a/drivers/watchdog/Makefile
>>>> +++ b/drivers/watchdog/Makefile
>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>   obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>   obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>   obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>   obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>   obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>   obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>   obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>> +
>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>> index ebe29c7409..38e82a6b6b 100644
>>>> --- a/drivers/watchdog/rti_wdt.c
>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>> @@ -14,6 +14,7 @@
>>>>   #include <power-domain.h>
>>>>   #include <wdt.h>
>>>>   #include <asm/io.h>
>>>> +#include <remoteproc.h>
>>>>   /* Timer register set definition */
>>>>   #define RTIDWDCTRL        0x90
>>>> @@ -37,11 +38,16 @@
>>>>   #define WDT_PRELOAD_MAX        0xfff
>>>> +#define RTI_PROC_ID        0
>>>
>>> Can we get the rproc id from DT?
>>
>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>
>
> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
> excludes usage for the J721E for now, but that one is fine without firmware -
> provided there is way to prevent power-down for RTI watchdog otherwise...

I was more of thinking to have a DT property to reference R5-core. But anyways,
the property is not present in kernel. I am okay with this for now.

>
>>>
>>>> +
>>>>   struct rti_wdt_priv {
>>>>       phys_addr_t regs;
>>>>       unsigned int clk_khz;
>>>>   };
>>>> +extern const u32 rti_wdt_fw[];
>>>> +extern const int rti_wdt_fw_size;
>>>
>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>
>> How does that work? Some example for me?
>>
>
> If you happen to refer to fs-loader: That does not target OSPI, our primary use
> case.

No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
firmware.

>
>> What benefit would that bring? There are other users of this pattern, e.g.
>> board/xilinx/zynqmp/pm_cfg_obj.S.

I didn't know U-Boot is accepting this. Tom, is this the preferred way for
including firmware images?

>>
>
> The only benefit of an alternative loading mechanism seems to be handling of
> larger images from different sources. But that's what I would tackle via boot
> scripting and, thus, without this feature. If you only have a few hundred bytes
> to embed, like for k3-rti-wdt, you quickly have a lot of overhead with other
> approaches.

hmm.. Does the build break if firmware is not present?

Thanks and regards,
Lokesh

>
> Jan
>
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
On 29.06.20 04:26, Lokesh Vutla wrote:

> +Tom
>
> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>> On 23.06.20 14:37, Jan Kiszka wrote:
>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>
>>>>
>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>> From: Jan Kiszka <[hidden email]>
>>>>>
>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>> embedded into U-Boot binary.
>>>>>
>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>
>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>> ---
>>>>>    drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>    drivers/watchdog/Makefile     |  3 +++
>>>>>    drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>    drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>    4 files changed, 67 insertions(+)
>>>>>    create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>
>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>> --- a/drivers/watchdog/Kconfig
>>>>> +++ b/drivers/watchdog/Kconfig
>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>          Say Y here if you want to include support for the K3 watchdog
>>>>>          timer (RTI module) available in the K3 generation of processors.
>>>>> +if WDT_K3_RTI
>>>>> +
>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>> +    bool "Load watchdog firmware"
>>>>> +    depends on REMOTEPROC
>>>>> +    help
>>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>> +
>>>>> +config WDT_K3_RTI_FW_FILE
>>>>> +    string "Watchdog firmware image file"
>>>>> +    default "k3-rti-wdt.fw"
>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>> +    help
>>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>> +      start.
>>>>> +
>>>>> +endif
>>>>> +
>>>>>    config WDT_SANDBOX
>>>>>        bool "Enable Watchdog Timer support for Sandbox"
>>>>>        depends on SANDBOX && WDT
>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>> index 16bdbf4970..bf58684875 100644
>>>>> --- a/drivers/watchdog/Makefile
>>>>> +++ b/drivers/watchdog/Makefile
>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>    obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>    obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>    obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>    obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>    obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>    obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>    obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>> +
>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>> @@ -14,6 +14,7 @@
>>>>>    #include <power-domain.h>
>>>>>    #include <wdt.h>
>>>>>    #include <asm/io.h>
>>>>> +#include <remoteproc.h>
>>>>>    /* Timer register set definition */
>>>>>    #define RTIDWDCTRL        0x90
>>>>> @@ -37,11 +38,16 @@
>>>>>    #define WDT_PRELOAD_MAX        0xfff
>>>>> +#define RTI_PROC_ID        0
>>>>
>>>> Can we get the rproc id from DT?
>>>
>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>
>>
>> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
>> excludes usage for the J721E for now, but that one is fine without firmware -
>> provided there is way to prevent power-down for RTI watchdog otherwise...
>
> I was more of thinking to have a DT property to reference R5-core. But anyways,
> the property is not present in kernel. I am okay with this for now.
>
>>
>>>>
>>>>> +
>>>>>    struct rti_wdt_priv {
>>>>>        phys_addr_t regs;
>>>>>        unsigned int clk_khz;
>>>>>    };
>>>>> +extern const u32 rti_wdt_fw[];
>>>>> +extern const int rti_wdt_fw_size;
>>>>
>>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>>
>>> How does that work? Some example for me?
>>>
>>
>> If you happen to refer to fs-loader: That does not target OSPI, our primary use
>> case.
>
> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
> firmware.

In case of our board, that image is not processed by U-Boot (only
generated). Also, processing it from the R5 loader would imply putting
remoteproc support into that level, duplicating what we have in A53 U-Boot.

>
>>
>>> What benefit would that bring? There are other users of this pattern, e.g.
>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>
> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
> including firmware images?
>
>>>
>>
>> The only benefit of an alternative loading mechanism seems to be handling of
>> larger images from different sources. But that's what I would tackle via boot
>> scripting and, thus, without this feature. If you only have a few hundred bytes
>> to embed, like for k3-rti-wdt, you quickly have a lot of overhead with other
>> approaches.
>
> hmm.. Does the build break if firmware is not present?

Yes, if you configure to include the firmware but specify an invalid
path, the build breaks.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Lokesh Vutla


On 29/06/20 10:20 am, Jan Kiszka wrote:

> On 29.06.20 04:26, Lokesh Vutla wrote:
>> +Tom
>>
>> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>>> On 23.06.20 14:37, Jan Kiszka wrote:
>>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>>
>>>>>
>>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>>> From: Jan Kiszka <[hidden email]>
>>>>>>
>>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>>> embedded into U-Boot binary.
>>>>>>
>>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>>
>>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>>> ---
>>>>>>    drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>>    drivers/watchdog/Makefile     |  3 +++
>>>>>>    drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>>    drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>>    4 files changed, 67 insertions(+)
>>>>>>    create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>>
>>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>>> --- a/drivers/watchdog/Kconfig
>>>>>> +++ b/drivers/watchdog/Kconfig
>>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>>          Say Y here if you want to include support for the K3 watchdog
>>>>>>          timer (RTI module) available in the K3 generation of processors.
>>>>>> +if WDT_K3_RTI
>>>>>> +
>>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>>> +    bool "Load watchdog firmware"
>>>>>> +    depends on REMOTEPROC
>>>>>> +    help
>>>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>>> +
>>>>>> +config WDT_K3_RTI_FW_FILE
>>>>>> +    string "Watchdog firmware image file"
>>>>>> +    default "k3-rti-wdt.fw"
>>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>>> +    help
>>>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>>> +      start.
>>>>>> +
>>>>>> +endif
>>>>>> +
>>>>>>    config WDT_SANDBOX
>>>>>>        bool "Enable Watchdog Timer support for Sandbox"
>>>>>>        depends on SANDBOX && WDT
>>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>>> index 16bdbf4970..bf58684875 100644
>>>>>> --- a/drivers/watchdog/Makefile
>>>>>> +++ b/drivers/watchdog/Makefile
>>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>>    obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>>    obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>>    obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>>    obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>>    obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>>    obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>>    obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>>> +
>>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>>> @@ -14,6 +14,7 @@
>>>>>>    #include <power-domain.h>
>>>>>>    #include <wdt.h>
>>>>>>    #include <asm/io.h>
>>>>>> +#include <remoteproc.h>
>>>>>>    /* Timer register set definition */
>>>>>>    #define RTIDWDCTRL        0x90
>>>>>> @@ -37,11 +38,16 @@
>>>>>>    #define WDT_PRELOAD_MAX        0xfff
>>>>>> +#define RTI_PROC_ID        0
>>>>>
>>>>> Can we get the rproc id from DT?
>>>>
>>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>>
>>>
>>> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
>>> excludes usage for the J721E for now, but that one is fine without firmware -
>>> provided there is way to prevent power-down for RTI watchdog otherwise...
>>
>> I was more of thinking to have a DT property to reference R5-core. But anyways,
>> the property is not present in kernel. I am okay with this for now.
>>
>>>
>>>>>
>>>>>> +
>>>>>>    struct rti_wdt_priv {
>>>>>>        phys_addr_t regs;
>>>>>>        unsigned int clk_khz;
>>>>>>    };
>>>>>> +extern const u32 rti_wdt_fw[];
>>>>>> +extern const int rti_wdt_fw_size;
>>>>>
>>>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>>>
>>>> How does that work? Some example for me?
>>>>
>>>
>>> If you happen to refer to fs-loader: That does not target OSPI, our primary use
>>> case.
>>
>> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
>> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
>> firmware.
>
> In case of our board, that image is not processed by U-Boot (only generated).
> Also, processing it from the R5 loader would imply putting remoteproc support
> into that level, duplicating what we have in A53 U-Boot.
>
>>
>>>
>>>> What benefit would that bring? There are other users of this pattern, e.g.
>>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>>
>> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
>> including firmware images?
>>
>>>>
>>>
>>> The only benefit of an alternative loading mechanism seems to be handling of
>>> larger images from different sources. But that's what I would tackle via boot
>>> scripting and, thus, without this feature. If you only have a few hundred bytes
>>> to embed, like for k3-rti-wdt, you quickly have a lot of overhead with other
>>> approaches.
>>
>> hmm.. Does the build break if firmware is not present?
>
> Yes, if you configure to include the firmware but specify an invalid path, the
> build breaks.

So, how do we handle the travis CI/gitlab build without this firmware. I am not
sure how xilinx is handling this. It should be the same case in the above
scenario you pointed out.

Thanks and regards,
Lokesh


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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
On 29.06.20 06:54, Lokesh Vutla wrote:

>
>
> On 29/06/20 10:20 am, Jan Kiszka wrote:
>> On 29.06.20 04:26, Lokesh Vutla wrote:
>>> +Tom
>>>
>>> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>>>> On 23.06.20 14:37, Jan Kiszka wrote:
>>>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>>>
>>>>>>
>>>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>>>> From: Jan Kiszka <[hidden email]>
>>>>>>>
>>>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>>>> embedded into U-Boot binary.
>>>>>>>
>>>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>>>
>>>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>>>> ---
>>>>>>>     drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>>>     drivers/watchdog/Makefile     |  3 +++
>>>>>>>     drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>>>     drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>>>     4 files changed, 67 insertions(+)
>>>>>>>     create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>>>
>>>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>>>> --- a/drivers/watchdog/Kconfig
>>>>>>> +++ b/drivers/watchdog/Kconfig
>>>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>>>           Say Y here if you want to include support for the K3 watchdog
>>>>>>>           timer (RTI module) available in the K3 generation of processors.
>>>>>>> +if WDT_K3_RTI
>>>>>>> +
>>>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>>>> +    bool "Load watchdog firmware"
>>>>>>> +    depends on REMOTEPROC
>>>>>>> +    help
>>>>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>>>> +
>>>>>>> +config WDT_K3_RTI_FW_FILE
>>>>>>> +    string "Watchdog firmware image file"
>>>>>>> +    default "k3-rti-wdt.fw"
>>>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>>>> +    help
>>>>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>>>> +      start.
>>>>>>> +
>>>>>>> +endif
>>>>>>> +
>>>>>>>     config WDT_SANDBOX
>>>>>>>         bool "Enable Watchdog Timer support for Sandbox"
>>>>>>>         depends on SANDBOX && WDT
>>>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>>>> index 16bdbf4970..bf58684875 100644
>>>>>>> --- a/drivers/watchdog/Makefile
>>>>>>> +++ b/drivers/watchdog/Makefile
>>>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>>>     obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>>>     obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>>>     obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>>>     obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>>>     obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>>>     obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>>>     obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>>>> +
>>>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>>>> @@ -14,6 +14,7 @@
>>>>>>>     #include <power-domain.h>
>>>>>>>     #include <wdt.h>
>>>>>>>     #include <asm/io.h>
>>>>>>> +#include <remoteproc.h>
>>>>>>>     /* Timer register set definition */
>>>>>>>     #define RTIDWDCTRL        0x90
>>>>>>> @@ -37,11 +38,16 @@
>>>>>>>     #define WDT_PRELOAD_MAX        0xfff
>>>>>>> +#define RTI_PROC_ID        0
>>>>>>
>>>>>> Can we get the rproc id from DT?
>>>>>
>>>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>>>
>>>>
>>>> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
>>>> excludes usage for the J721E for now, but that one is fine without firmware -
>>>> provided there is way to prevent power-down for RTI watchdog otherwise...
>>>
>>> I was more of thinking to have a DT property to reference R5-core. But anyways,
>>> the property is not present in kernel. I am okay with this for now.
>>>
>>>>
>>>>>>
>>>>>>> +
>>>>>>>     struct rti_wdt_priv {
>>>>>>>         phys_addr_t regs;
>>>>>>>         unsigned int clk_khz;
>>>>>>>     };
>>>>>>> +extern const u32 rti_wdt_fw[];
>>>>>>> +extern const int rti_wdt_fw_size;
>>>>>>
>>>>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>>>>
>>>>> How does that work? Some example for me?
>>>>>
>>>>
>>>> If you happen to refer to fs-loader: That does not target OSPI, our primary use
>>>> case.
>>>
>>> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
>>> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
>>> firmware.
>>
>> In case of our board, that image is not processed by U-Boot (only generated).
>> Also, processing it from the R5 loader would imply putting remoteproc support
>> into that level, duplicating what we have in A53 U-Boot.
>>
>>>
>>>>
>>>>> What benefit would that bring? There are other users of this pattern, e.g.
>>>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>>>
>>> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
>>> including firmware images?
>>>
>>>>>
>>>>
>>>> The only benefit of an alternative loading mechanism seems to be handling of
>>>> larger images from different sources. But that's what I would tackle via boot
>>>> scripting and, thus, without this feature. If you only have a few hundred bytes
>>>> to embed, like for k3-rti-wdt, you quickly have a lot of overhead with other
>>>> approaches.
>>>
>>> hmm.. Does the build break if firmware is not present?
>>
>> Yes, if you configure to include the firmware but specify an invalid path, the
>> build breaks.
>
> So, how do we handle the travis CI/gitlab build without this firmware. I am not
> sure how xilinx is handling this. It should be the same case in the above
> scenario you pointed out.

You mean some all-yes-config? We could create a dummy image prior to
running that build.

The Xilinx has its logic disabled when the file name is empty, which is
the default. The linker should kick unused bits out then. I can try that
as well.

Jan

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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Tom Rini-4
In reply to this post by Lokesh Vutla
On Mon, Jun 29, 2020 at 07:56:53AM +0530, Lokesh Vutla wrote:

> +Tom
>
> On 23/06/20 8:11 pm, Jan Kiszka wrote:
> > On 23.06.20 14:37, Jan Kiszka wrote:
> >> On 23.06.20 13:50, Lokesh Vutla wrote:
> >>>
> >>>
> >>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
> >>>> From: Jan Kiszka <[hidden email]>
> >>>>
> >>>> To avoid the need of extra boot scripting on AM65x for loading a
> >>>> watchdog firmware, add the required rproc init and loading logic for the
> >>>> first R5F core to the watchdog start handler. The firmware itself is
> >>>> embedded into U-Boot binary.
> >>>>
> >>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
> >>>>
> >>>> Signed-off-by: Jan Kiszka <[hidden email]>
> >>>> ---
> >>>>   drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
> >>>>   drivers/watchdog/Makefile     |  3 +++
> >>>>   drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
> >>>>   drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
> >>>>   4 files changed, 67 insertions(+)
> >>>>   create mode 100644 drivers/watchdog/rti_wdt_fw.S
> >>>>
> >>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> >>>> index ee99bd2af1..fd6ab9a85b 100644
> >>>> --- a/drivers/watchdog/Kconfig
> >>>> +++ b/drivers/watchdog/Kconfig
> >>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
> >>>>         Say Y here if you want to include support for the K3 watchdog
> >>>>         timer (RTI module) available in the K3 generation of processors.
> >>>> +if WDT_K3_RTI
> >>>> +
> >>>> +config WDT_K3_RTI_LOAD_FW
> >>>> +    bool "Load watchdog firmware"
> >>>> +    depends on REMOTEPROC
> >>>> +    help
> >>>> +      Automatically load the specified firmware image into the MCU R5F
> >>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
> >>>> +      of the watchdog timer, typically by resetting the system.
> >>>> +
> >>>> +config WDT_K3_RTI_FW_FILE
> >>>> +    string "Watchdog firmware image file"
> >>>> +    default "k3-rti-wdt.fw"
> >>>> +    depends on WDT_K3_RTI_LOAD_FW
> >>>> +    help
> >>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
> >>>> +      start.
> >>>> +
> >>>> +endif
> >>>> +
> >>>>   config WDT_SANDBOX
> >>>>       bool "Enable Watchdog Timer support for Sandbox"
> >>>>       depends on SANDBOX && WDT
> >>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> >>>> index 16bdbf4970..bf58684875 100644
> >>>> --- a/drivers/watchdog/Makefile
> >>>> +++ b/drivers/watchdog/Makefile
> >>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
> >>>>   obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
> >>>>   obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
> >>>>   obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
> >>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
> >>>>   obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
> >>>>   obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
> >>>>   obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
> >>>>   obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
> >>>> +
> >>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
> >>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
> >>>> index ebe29c7409..38e82a6b6b 100644
> >>>> --- a/drivers/watchdog/rti_wdt.c
> >>>> +++ b/drivers/watchdog/rti_wdt.c
> >>>> @@ -14,6 +14,7 @@
> >>>>   #include <power-domain.h>
> >>>>   #include <wdt.h>
> >>>>   #include <asm/io.h>
> >>>> +#include <remoteproc.h>
> >>>>   /* Timer register set definition */
> >>>>   #define RTIDWDCTRL        0x90
> >>>> @@ -37,11 +38,16 @@
> >>>>   #define WDT_PRELOAD_MAX        0xfff
> >>>> +#define RTI_PROC_ID        0
> >>>
> >>> Can we get the rproc id from DT?
> >>
> >> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
> >>
> >
> > I'm now probing for the first instance of "ti,am654-r5f" compatible. That
> > excludes usage for the J721E for now, but that one is fine without firmware -
> > provided there is way to prevent power-down for RTI watchdog otherwise...
>
> I was more of thinking to have a DT property to reference R5-core. But anyways,
> the property is not present in kernel. I am okay with this for now.
Note that not all properties in a DT in Linux need to be used in Linux,
this is something I _think_ there is growing understanding of.

> >>>> +
> >>>>   struct rti_wdt_priv {
> >>>>       phys_addr_t regs;
> >>>>       unsigned int clk_khz;
> >>>>   };
> >>>> +extern const u32 rti_wdt_fw[];
> >>>> +extern const int rti_wdt_fw_size;
> >>>
> >>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
> >>
> >> How does that work? Some example for me?
> >>
> >
> > If you happen to refer to fs-loader: That does not target OSPI, our primary use
> > case.
>
> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
> firmware.
>
> >
> >> What benefit would that bring? There are other users of this pattern, e.g.
> >> board/xilinx/zynqmp/pm_cfg_obj.S.
>
> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
> including firmware images?
Adding in Michal.  Why is this area doing what it's doing and not one of
the other generic ways to handle this problem?  Thanks!

--
Tom

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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
On 29.06.20 14:37, Tom Rini wrote:

> On Mon, Jun 29, 2020 at 07:56:53AM +0530, Lokesh Vutla wrote:
>> +Tom
>>
>> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>>> On 23.06.20 14:37, Jan Kiszka wrote:
>>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>>
>>>>>
>>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>>> From: Jan Kiszka <[hidden email]>
>>>>>>
>>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>>> embedded into U-Boot binary.
>>>>>>
>>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>>
>>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>>> ---
>>>>>>    drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>>    drivers/watchdog/Makefile     |  3 +++
>>>>>>    drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>>    drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>>    4 files changed, 67 insertions(+)
>>>>>>    create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>>
>>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>>> --- a/drivers/watchdog/Kconfig
>>>>>> +++ b/drivers/watchdog/Kconfig
>>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>>          Say Y here if you want to include support for the K3 watchdog
>>>>>>          timer (RTI module) available in the K3 generation of processors.
>>>>>> +if WDT_K3_RTI
>>>>>> +
>>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>>> +    bool "Load watchdog firmware"
>>>>>> +    depends on REMOTEPROC
>>>>>> +    help
>>>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>>> +
>>>>>> +config WDT_K3_RTI_FW_FILE
>>>>>> +    string "Watchdog firmware image file"
>>>>>> +    default "k3-rti-wdt.fw"
>>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>>> +    help
>>>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>>> +      start.
>>>>>> +
>>>>>> +endif
>>>>>> +
>>>>>>    config WDT_SANDBOX
>>>>>>        bool "Enable Watchdog Timer support for Sandbox"
>>>>>>        depends on SANDBOX && WDT
>>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>>> index 16bdbf4970..bf58684875 100644
>>>>>> --- a/drivers/watchdog/Makefile
>>>>>> +++ b/drivers/watchdog/Makefile
>>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>>    obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>>    obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>>    obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>>    obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>>    obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>>    obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>>    obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>>> +
>>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>>> @@ -14,6 +14,7 @@
>>>>>>    #include <power-domain.h>
>>>>>>    #include <wdt.h>
>>>>>>    #include <asm/io.h>
>>>>>> +#include <remoteproc.h>
>>>>>>    /* Timer register set definition */
>>>>>>    #define RTIDWDCTRL        0x90
>>>>>> @@ -37,11 +38,16 @@
>>>>>>    #define WDT_PRELOAD_MAX        0xfff
>>>>>> +#define RTI_PROC_ID        0
>>>>>
>>>>> Can we get the rproc id from DT?
>>>>
>>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>>
>>>
>>> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
>>> excludes usage for the J721E for now, but that one is fine without firmware -
>>> provided there is way to prevent power-down for RTI watchdog otherwise...
>>
>> I was more of thinking to have a DT property to reference R5-core. But anyways,
>> the property is not present in kernel. I am okay with this for now.
>
> Note that not all properties in a DT in Linux need to be used in Linux,
> this is something I _think_ there is growing understanding of.
>
>>>>>> +
>>>>>>    struct rti_wdt_priv {
>>>>>>        phys_addr_t regs;
>>>>>>        unsigned int clk_khz;
>>>>>>    };
>>>>>> +extern const u32 rti_wdt_fw[];
>>>>>> +extern const int rti_wdt_fw_size;
>>>>>
>>>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>>>
>>>> How does that work? Some example for me?
>>>>
>>>
>>> If you happen to refer to fs-loader: That does not target OSPI, our primary use
>>> case.
>>
>> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
>> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
>> firmware.
>>
>>>
>>>> What benefit would that bring? There are other users of this pattern, e.g.
>>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>>
>> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
>> including firmware images?
>
> Adding in Michal.  Why is this area doing what it's doing and not one of
> the other generic ways to handle this problem?  Thanks!
>

So, what are the recommended "generic ways" for these use cases?

Is there a way to stick own stuff into u-boot.itb and get that provided
to some handler of U-Boot proper? Seems unlikely. The pattern I found
pushes the firmware into the kernel fit image - which is a clear no-go
for the watchdog use case because it shall monitor the booting of that
very same image (software update case).

Jan

--
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Corporate Competence Center Embedded Linux
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
On 29.06.20 20:44, Jan Kiszka wrote:

> On 29.06.20 14:37, Tom Rini wrote:
>> On Mon, Jun 29, 2020 at 07:56:53AM +0530, Lokesh Vutla wrote:
>>> +Tom
>>>
>>> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>>>> On 23.06.20 14:37, Jan Kiszka wrote:
>>>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>>>
>>>>>>
>>>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>>>> From: Jan Kiszka <[hidden email]>
>>>>>>>
>>>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>>>> watchdog firmware, add the required rproc init and loading logic
>>>>>>> for the
>>>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>>>> embedded into U-Boot binary.
>>>>>>>
>>>>>>> One possible firmware source is
>>>>>>> https://github.com/siemens/k3-rti-wdt.
>>>>>>>
>>>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>>>> ---
>>>>>>>    drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>>>    drivers/watchdog/Makefile     |  3 +++
>>>>>>>    drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>>>    drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>>>    4 files changed, 67 insertions(+)
>>>>>>>    create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>>>
>>>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>>>> --- a/drivers/watchdog/Kconfig
>>>>>>> +++ b/drivers/watchdog/Kconfig
>>>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>>>          Say Y here if you want to include support for the K3
>>>>>>> watchdog
>>>>>>>          timer (RTI module) available in the K3 generation of
>>>>>>> processors.
>>>>>>> +if WDT_K3_RTI
>>>>>>> +
>>>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>>>> +    bool "Load watchdog firmware"
>>>>>>> +    depends on REMOTEPROC
>>>>>>> +    help
>>>>>>> +      Automatically load the specified firmware image into the
>>>>>>> MCU R5F
>>>>>>> +      core 0. On the AM65x, this firmware is supposed to handle
>>>>>>> the expiry
>>>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>>>> +
>>>>>>> +config WDT_K3_RTI_FW_FILE
>>>>>>> +    string "Watchdog firmware image file"
>>>>>>> +    default "k3-rti-wdt.fw"
>>>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>>>> +    help
>>>>>>> +      Firmware image to be embedded into U-Boot and loaded on
>>>>>>> watchdog
>>>>>>> +      start.
>>>>>>> +
>>>>>>> +endif
>>>>>>> +
>>>>>>>    config WDT_SANDBOX
>>>>>>>        bool "Enable Watchdog Timer support for Sandbox"
>>>>>>>        depends on SANDBOX && WDT
>>>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>>>> index 16bdbf4970..bf58684875 100644
>>>>>>> --- a/drivers/watchdog/Makefile
>>>>>>> +++ b/drivers/watchdog/Makefile
>>>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>>>    obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>>>    obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>>>    obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>>>    obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>>>    obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>>>    obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>>>    obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>>>> +
>>>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f
>>>>>>> $(CONFIG_WDT_K3_RTI_FW_FILE)) FORCE
>>>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>>>> @@ -14,6 +14,7 @@
>>>>>>>    #include <power-domain.h>
>>>>>>>    #include <wdt.h>
>>>>>>>    #include <asm/io.h>
>>>>>>> +#include <remoteproc.h>
>>>>>>>    /* Timer register set definition */
>>>>>>>    #define RTIDWDCTRL        0x90
>>>>>>> @@ -37,11 +38,16 @@
>>>>>>>    #define WDT_PRELOAD_MAX        0xfff
>>>>>>> +#define RTI_PROC_ID        0
>>>>>>
>>>>>> Can we get the rproc id from DT?
>>>>>
>>>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>>>
>>>>
>>>> I'm now probing for the first instance of "ti,am654-r5f" compatible.
>>>> That
>>>> excludes usage for the J721E for now, but that one is fine without
>>>> firmware -
>>>> provided there is way to prevent power-down for RTI watchdog
>>>> otherwise...
>>>
>>> I was more of thinking to have a DT property to reference R5-core.
>>> But anyways,
>>> the property is not present in kernel. I am okay with this for now.
>>
>> Note that not all properties in a DT in Linux need to be used in Linux,
>> this is something I _think_ there is growing understanding of.
>>
>>>>>>> +
>>>>>>>    struct rti_wdt_priv {
>>>>>>>        phys_addr_t regs;
>>>>>>>        unsigned int clk_khz;
>>>>>>>    };
>>>>>>> +extern const u32 rti_wdt_fw[];
>>>>>>> +extern const int rti_wdt_fw_size;
>>>>>>
>>>>>> FIT is the preferred way of packing images in U-Boot. Can you try
>>>>>> using it?
>>>>>
>>>>> How does that work? Some example for me?
>>>>>
>>>>
>>>> If you happen to refer to fs-loader: That does not target OSPI, our
>>>> primary use
>>>> case.
>>>
>>> No. I was thinking to pack the image in FIT along with ATF and OPTEE
>>> like in
>>> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for
>>> installing the
>>> firmware.
>>>
>>>>
>>>>> What benefit would that bring? There are other users of this
>>>>> pattern, e.g.
>>>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>>>
>>> I didn't know U-Boot is accepting this. Tom, is this the preferred
>>> way for
>>> including firmware images?
>>
>> Adding in Michal.  Why is this area doing what it's doing and not one of
>> the other generic ways to handle this problem?  Thanks!
>>
>
> So, what are the recommended "generic ways" for these use cases?
>
> Is there a way to stick own stuff into u-boot.itb and get that provided
> to some handler of U-Boot proper? Seems unlikely. The pattern I found
> pushes the firmware into the kernel fit image - which is a clear no-go
> for the watchdog use case because it shall monitor the booting of that
> very same image (software update case).
>
> Jan
>

Ping on this. I'd like to move forward with this series.

Jan

--
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Corporate Competence Center Embedded Linux
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Lokesh Vutla
Hi Jan,

On 20/07/20 3:06 pm, Jan Kiszka wrote:

> On 29.06.20 20:44, Jan Kiszka wrote:
>> On 29.06.20 14:37, Tom Rini wrote:
>>> On Mon, Jun 29, 2020 at 07:56:53AM +0530, Lokesh Vutla wrote:
>>>> +Tom
>>>>
>>>> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>>>>> On 23.06.20 14:37, Jan Kiszka wrote:
>>>>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>>>>
>>>>>>>
>>>>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>>>>> From: Jan Kiszka <[hidden email]>
>>>>>>>>
>>>>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>>>>> embedded into U-Boot binary.
>>>>>>>>
>>>>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>>>>
>>>>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>>>>> ---
>>>>>>>>    drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>>>>    drivers/watchdog/Makefile     |  3 +++
>>>>>>>>    drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>>>>    drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>>>>    4 files changed, 67 insertions(+)
>>>>>>>>    create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>>>>
>>>>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>>>>> --- a/drivers/watchdog/Kconfig
>>>>>>>> +++ b/drivers/watchdog/Kconfig
>>>>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>>>>          Say Y here if you want to include support for the K3 watchdog
>>>>>>>>          timer (RTI module) available in the K3 generation of processors.
>>>>>>>> +if WDT_K3_RTI
>>>>>>>> +
>>>>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>>>>> +    bool "Load watchdog firmware"
>>>>>>>> +    depends on REMOTEPROC
>>>>>>>> +    help
>>>>>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>>>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>>>>> +
>>>>>>>> +config WDT_K3_RTI_FW_FILE
>>>>>>>> +    string "Watchdog firmware image file"
>>>>>>>> +    default "k3-rti-wdt.fw"
>>>>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>>>>> +    help
>>>>>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>>>>> +      start.
>>>>>>>> +
>>>>>>>> +endif
>>>>>>>> +
>>>>>>>>    config WDT_SANDBOX
>>>>>>>>        bool "Enable Watchdog Timer support for Sandbox"
>>>>>>>>        depends on SANDBOX && WDT
>>>>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>>>>> index 16bdbf4970..bf58684875 100644
>>>>>>>> --- a/drivers/watchdog/Makefile
>>>>>>>> +++ b/drivers/watchdog/Makefile
>>>>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>>>>    obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>>>>    obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>>>>    obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>>>>    obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>>>>    obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>>>>    obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>>>>    obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>>>>> +
>>>>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE))
>>>>>>>> FORCE
>>>>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>>>>> @@ -14,6 +14,7 @@
>>>>>>>>    #include <power-domain.h>
>>>>>>>>    #include <wdt.h>
>>>>>>>>    #include <asm/io.h>
>>>>>>>> +#include <remoteproc.h>
>>>>>>>>    /* Timer register set definition */
>>>>>>>>    #define RTIDWDCTRL        0x90
>>>>>>>> @@ -37,11 +38,16 @@
>>>>>>>>    #define WDT_PRELOAD_MAX        0xfff
>>>>>>>> +#define RTI_PROC_ID        0
>>>>>>>
>>>>>>> Can we get the rproc id from DT?
>>>>>>
>>>>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>>>>
>>>>>
>>>>> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
>>>>> excludes usage for the J721E for now, but that one is fine without firmware -
>>>>> provided there is way to prevent power-down for RTI watchdog otherwise...
>>>>
>>>> I was more of thinking to have a DT property to reference R5-core. But anyways,
>>>> the property is not present in kernel. I am okay with this for now.
>>>
>>> Note that not all properties in a DT in Linux need to be used in Linux,
>>> this is something I _think_ there is growing understanding of.
>>>
>>>>>>>> +
>>>>>>>>    struct rti_wdt_priv {
>>>>>>>>        phys_addr_t regs;
>>>>>>>>        unsigned int clk_khz;
>>>>>>>>    };
>>>>>>>> +extern const u32 rti_wdt_fw[];
>>>>>>>> +extern const int rti_wdt_fw_size;
>>>>>>>
>>>>>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>>>>>
>>>>>> How does that work? Some example for me?
>>>>>>
>>>>>
>>>>> If you happen to refer to fs-loader: That does not target OSPI, our primary
>>>>> use
>>>>> case.
>>>>
>>>> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
>>>> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
>>>> firmware.
>>>>
>>>>>
>>>>>> What benefit would that bring? There are other users of this pattern, e.g.
>>>>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>>>>
>>>> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
>>>> including firmware images?
>>>
>>> Adding in Michal.  Why is this area doing what it's doing and not one of
>>> the other generic ways to handle this problem?  Thanks!
>>>
>>
>> So, what are the recommended "generic ways" for these use cases?
>>
>> Is there a way to stick own stuff into u-boot.itb and get that provided to
>> some handler of U-Boot proper? Seems unlikely. The pattern I found pushes the
>> firmware into the kernel fit image - which is a clear no-go for the watchdog
>> use case because it shall monitor the booting of that very same image
>> (software update case).
>>
>> Jan
>>
>
> Ping on this. I'd like to move forward with this series.

If you want remotecore to be loaded early, then my preference would be to pack
Firmware inside FIT image(along with A72 SPL, ATF or A72 U-Boot) as loadable and
register a handle to load and start the rproc in SPL. If it can be delayed, I
prefer to do at U-Boot prompt.


However, the driver can be merged separately. If you can re post the driver part
I can pull it in soon.

Thanks and regards,
Lokesh
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Re: [PATCH v2 2/3] watchdog: rti_wdt: Add support for loading firmware

Jan Kiszka
On 21.07.20 07:27, Lokesh Vutla wrote:

> Hi Jan,
>
> On 20/07/20 3:06 pm, Jan Kiszka wrote:
>> On 29.06.20 20:44, Jan Kiszka wrote:
>>> On 29.06.20 14:37, Tom Rini wrote:
>>>> On Mon, Jun 29, 2020 at 07:56:53AM +0530, Lokesh Vutla wrote:
>>>>> +Tom
>>>>>
>>>>> On 23/06/20 8:11 pm, Jan Kiszka wrote:
>>>>>> On 23.06.20 14:37, Jan Kiszka wrote:
>>>>>>> On 23.06.20 13:50, Lokesh Vutla wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>>>>>>>>> From: Jan Kiszka <[hidden email]>
>>>>>>>>>
>>>>>>>>> To avoid the need of extra boot scripting on AM65x for loading a
>>>>>>>>> watchdog firmware, add the required rproc init and loading logic for the
>>>>>>>>> first R5F core to the watchdog start handler. The firmware itself is
>>>>>>>>> embedded into U-Boot binary.
>>>>>>>>>
>>>>>>>>> One possible firmware source is https://github.com/siemens/k3-rti-wdt.
>>>>>>>>>
>>>>>>>>> Signed-off-by: Jan Kiszka <[hidden email]>
>>>>>>>>> ---
>>>>>>>>>     drivers/watchdog/Kconfig      | 20 ++++++++++++++++++++
>>>>>>>>>     drivers/watchdog/Makefile     |  3 +++
>>>>>>>>>     drivers/watchdog/rti_wdt.c    | 24 ++++++++++++++++++++++++
>>>>>>>>>     drivers/watchdog/rti_wdt_fw.S | 20 ++++++++++++++++++++
>>>>>>>>>     4 files changed, 67 insertions(+)
>>>>>>>>>     create mode 100644 drivers/watchdog/rti_wdt_fw.S
>>>>>>>>>
>>>>>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>>>>>> index ee99bd2af1..fd6ab9a85b 100644
>>>>>>>>> --- a/drivers/watchdog/Kconfig
>>>>>>>>> +++ b/drivers/watchdog/Kconfig
>>>>>>>>> @@ -162,6 +162,26 @@ config WDT_K3_RTI
>>>>>>>>>           Say Y here if you want to include support for the K3 watchdog
>>>>>>>>>           timer (RTI module) available in the K3 generation of processors.
>>>>>>>>> +if WDT_K3_RTI
>>>>>>>>> +
>>>>>>>>> +config WDT_K3_RTI_LOAD_FW
>>>>>>>>> +    bool "Load watchdog firmware"
>>>>>>>>> +    depends on REMOTEPROC
>>>>>>>>> +    help
>>>>>>>>> +      Automatically load the specified firmware image into the MCU R5F
>>>>>>>>> +      core 0. On the AM65x, this firmware is supposed to handle the expiry
>>>>>>>>> +      of the watchdog timer, typically by resetting the system.
>>>>>>>>> +
>>>>>>>>> +config WDT_K3_RTI_FW_FILE
>>>>>>>>> +    string "Watchdog firmware image file"
>>>>>>>>> +    default "k3-rti-wdt.fw"
>>>>>>>>> +    depends on WDT_K3_RTI_LOAD_FW
>>>>>>>>> +    help
>>>>>>>>> +      Firmware image to be embedded into U-Boot and loaded on watchdog
>>>>>>>>> +      start.
>>>>>>>>> +
>>>>>>>>> +endif
>>>>>>>>> +
>>>>>>>>>     config WDT_SANDBOX
>>>>>>>>>         bool "Enable Watchdog Timer support for Sandbox"
>>>>>>>>>         depends on SANDBOX && WDT
>>>>>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>>>>>> index 16bdbf4970..bf58684875 100644
>>>>>>>>> --- a/drivers/watchdog/Makefile
>>>>>>>>> +++ b/drivers/watchdog/Makefile
>>>>>>>>> @@ -28,7 +28,10 @@ obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>>>>>>     obj-$(CONFIG_WDT_MTK) += mtk_wdt.o
>>>>>>>>>     obj-$(CONFIG_WDT_OMAP3) += omap_wdt.o
>>>>>>>>>     obj-$(CONFIG_WDT_K3_RTI) += rti_wdt.o
>>>>>>>>> +obj-$(CONFIG_WDT_K3_RTI_LOAD_FW) += rti_wdt_fw.o
>>>>>>>>>     obj-$(CONFIG_WDT_SP805) += sp805_wdt.o
>>>>>>>>>     obj-$(CONFIG_WDT_STM32MP) += stm32mp_wdt.o
>>>>>>>>>     obj-$(CONFIG_WDT_TANGIER) += tangier_wdt.o
>>>>>>>>>     obj-$(CONFIG_WDT_XILINX) += xilinx_wwdt.o
>>>>>>>>> +
>>>>>>>>> +$(obj)/rti_wdt_fw.o: $(shell readlink -f $(CONFIG_WDT_K3_RTI_FW_FILE))
>>>>>>>>> FORCE
>>>>>>>>> diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
>>>>>>>>> index ebe29c7409..38e82a6b6b 100644
>>>>>>>>> --- a/drivers/watchdog/rti_wdt.c
>>>>>>>>> +++ b/drivers/watchdog/rti_wdt.c
>>>>>>>>> @@ -14,6 +14,7 @@
>>>>>>>>>     #include <power-domain.h>
>>>>>>>>>     #include <wdt.h>
>>>>>>>>>     #include <asm/io.h>
>>>>>>>>> +#include <remoteproc.h>
>>>>>>>>>     /* Timer register set definition */
>>>>>>>>>     #define RTIDWDCTRL        0x90
>>>>>>>>> @@ -37,11 +38,16 @@
>>>>>>>>>     #define WDT_PRELOAD_MAX        0xfff
>>>>>>>>> +#define RTI_PROC_ID        0
>>>>>>>>
>>>>>>>> Can we get the rproc id from DT?
>>>>>>>
>>>>>>> You mean, resolve "mcu_r5fss0_core0" to the ID? Doable.
>>>>>>>
>>>>>>
>>>>>> I'm now probing for the first instance of "ti,am654-r5f" compatible. That
>>>>>> excludes usage for the J721E for now, but that one is fine without firmware -
>>>>>> provided there is way to prevent power-down for RTI watchdog otherwise...
>>>>>
>>>>> I was more of thinking to have a DT property to reference R5-core. But anyways,
>>>>> the property is not present in kernel. I am okay with this for now.
>>>>
>>>> Note that not all properties in a DT in Linux need to be used in Linux,
>>>> this is something I _think_ there is growing understanding of.
>>>>
>>>>>>>>> +
>>>>>>>>>     struct rti_wdt_priv {
>>>>>>>>>         phys_addr_t regs;
>>>>>>>>>         unsigned int clk_khz;
>>>>>>>>>     };
>>>>>>>>> +extern const u32 rti_wdt_fw[];
>>>>>>>>> +extern const int rti_wdt_fw_size;
>>>>>>>>
>>>>>>>> FIT is the preferred way of packing images in U-Boot. Can you try using it?
>>>>>>>
>>>>>>> How does that work? Some example for me?
>>>>>>>
>>>>>>
>>>>>> If you happen to refer to fs-loader: That does not target OSPI, our primary
>>>>>> use
>>>>>> case.
>>>>>
>>>>> No. I was thinking to pack the image in FIT along with ATF and OPTEE like in
>>>>> k3_fit_atf.sh and register a U_BOOT_FIT_LOADABLE_HANDLER for installing the
>>>>> firmware.
>>>>>
>>>>>>
>>>>>>> What benefit would that bring? There are other users of this pattern, e.g.
>>>>>>> board/xilinx/zynqmp/pm_cfg_obj.S.
>>>>>
>>>>> I didn't know U-Boot is accepting this. Tom, is this the preferred way for
>>>>> including firmware images?
>>>>
>>>> Adding in Michal.  Why is this area doing what it's doing and not one of
>>>> the other generic ways to handle this problem?  Thanks!
>>>>
>>>
>>> So, what are the recommended "generic ways" for these use cases?
>>>
>>> Is there a way to stick own stuff into u-boot.itb and get that provided to
>>> some handler of U-Boot proper? Seems unlikely. The pattern I found pushes the
>>> firmware into the kernel fit image - which is a clear no-go for the watchdog
>>> use case because it shall monitor the booting of that very same image
>>> (software update case).
>>>
>>> Jan
>>>
>>
>> Ping on this. I'd like to move forward with this series.
>
> If you want remotecore to be loaded early, then my preference would be to pack
> Firmware inside FIT image(along with A72 SPL, ATF or A72 U-Boot) as loadable and
> register a handle to load and start the rproc in SPL. If it can be delayed, I
> prefer to do at U-Boot prompt.
>

So far, we do not need it in SPL as we have no procedure to update
U-Boot proper safely. Moving things to SPL would imply carrying the
remoteproc infrastructure twice.

For loading from the prompt, we are still lacking a handy way to bundle
the firmware with the integrity-checked U-Boot proper. Yes, technically
I could push those 676 bytes into a fitimage, sign it, reserve a block
in SPI flash or some other storage, load it from there and validate it.
But that's overkill IMHO.

>
> However, the driver can be merged separately. If you can re post the driver part
> I can pull it in soon.

You could cherry-pick patch 1 and 3 for that already, they still apply.

Thanks,
Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
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Re: [PATCH v2 0/3] watchdog: K3: Add RTI watchdog support

Lokesh Vutla
In reply to this post by Jan Kiszka


On 23/06/20 4:45 pm, Jan Kiszka wrote:

> This brings watchdog support for the TI K3 SoCs, derived from the Linux
> kernel, augmented with firmware loading as needed on the AM65x.
>
> Tested on the AM65x EVM and the IOT2050 (also AM65x-based, upstream
> support will be posted soon).
>
> Changes in v2:
>  - keep watchdog powered when handing over to Linux
>  - drop unneeded explicit power-on
>  - account for RTI firmware locking the power domain

Patch 1 and 3 merged applied.

Thanks and regards,
Lokesh

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Re: [PATCH v2 0/3] watchdog: K3: Add RTI watchdog support

Jan Kiszka
On 11.08.20 12:33, Lokesh Vutla wrote:

>
>
> On 23/06/20 4:45 pm, Jan Kiszka wrote:
>> This brings watchdog support for the TI K3 SoCs, derived from the Linux
>> kernel, augmented with firmware loading as needed on the AM65x.
>>
>> Tested on the AM65x EVM and the IOT2050 (also AM65x-based, upstream
>> support will be posted soon).
>>
>> Changes in v2:
>>   - keep watchdog powered when handing over to Linux
>>   - drop unneeded explicit power-on
>>   - account for RTI firmware locking the power domain
>
> Patch 1 and 3 merged applied.
>

Thanks. Still taking workable suggestions for loading the firmware.

Jan

--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
12