[PATCH v3 1/2] trace: select TIMER_EARLY to avoid infinite recursion

[Pragnesh Patel]

When tracing functions is enabled this adds calls to
__cyg_profile_func_enter() and __cyg_profile_func_exit() to the traced
functions.

__cyg_profile_func_enter() and __cyg_profile_func_exit() invoke
timer_get_us() to record the entry and exit time.

initr_dm() will make gd->dm_root = NULL and gd->timer = NULL, so
timer_get_us() -> get_ticks() -> dm_timer_init() will lead to an
indefinite recursion.

So select TIMER_EARLY when tracing got enabled.

Signed-off-by: Pragnesh Patel <[hidden email]>
Reviewed-by: Simon Glass <[hidden email]>
Reviewed-by: Rick Chen <[hidden email]>
---

Changes in v3:
- no change

Changes in v2:
- new patch

 lib/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/Kconfig b/lib/Kconfig
index 7673d2e4e0..671386963a 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -210,6 +210,7 @@ config BITREVERSE
 config TRACE
  bool "Support for tracing of function calls and timing"
  imply CMD_TRACE
+ select TIMER_EARLY
  help
   Enables function tracing within U-Boot. This allows recording of call
   traces including timing information. The command can write data to
--
2.17.1

[Pragnesh Patel]

Added support for timer_early_get_count() and timer_early_get_rate()
This is mostly useful in tracing.

Signed-off-by: Pragnesh Patel <[hidden email]>
---

Changes in v3:
- Add IS_ENABLED(CONFIG_TIMER_EARLY) for timer_early_get_rate()
  and timer_early_get_count() functions.

Changes in v2:
- make u-boot compile for qemu (include/configs/qemu-riscv.h)

 drivers/timer/andes_plmt_timer.c   | 21 ++++++++++++++++++++-
 drivers/timer/riscv_timer.c        | 21 ++++++++++++++++++++-
 drivers/timer/sifive_clint_timer.c | 21 ++++++++++++++++++++-
 include/configs/ax25-ae350.h       |  5 +++++
 include/configs/qemu-riscv.h       |  5 +++++
 include/configs/sifive-fu540.h     |  5 +++++
 6 files changed, 75 insertions(+), 3 deletions(-)

diff --git a/drivers/timer/andes_plmt_timer.c b/drivers/timer/andes_plmt_timer.c
index cec86718c7..ce4040d76d 100644
--- a/drivers/timer/andes_plmt_timer.c
+++ b/drivers/timer/andes_plmt_timer.c
@@ -17,11 +17,30 @@
 /* mtime register */
 #define MTIME_REG(base) ((ulong)(base))
 
-static u64 andes_plmt_get_count(struct udevice *dev)
+static u64 notrace andes_plmt_get_count(struct udevice *dev)
 {
  return readq((void __iomem *)MTIME_REG(dev->priv));
 }
 
+#if CONFIG_IS_ENABLED(RISCV_MMODE) && IS_ENABLED(CONFIG_TIMER_EARLY)
+/**
+ * timer_early_get_rate() - Get the timer rate before driver model
+ */
+unsigned long notrace timer_early_get_rate(void)
+{
+ return RISCV_MMODE_TIMER_FREQ;
+}
+
+/**
+ * timer_early_get_count() - Get the timer count before driver model
+ *
+ */
+u64 notrace timer_early_get_count(void)
+{
+ return readq((void __iomem *)MTIME_REG(RISCV_MMODE_TIMERBASE));
+}
+#endif
+
 static const struct timer_ops andes_plmt_ops = {
  .get_count = andes_plmt_get_count,
 };
diff --git a/drivers/timer/riscv_timer.c b/drivers/timer/riscv_timer.c
index 21ae184057..3627ed79b8 100644
--- a/drivers/timer/riscv_timer.c
+++ b/drivers/timer/riscv_timer.c
@@ -16,7 +16,7 @@
 #include <timer.h>
 #include <asm/csr.h>
 
-static u64 riscv_timer_get_count(struct udevice *dev)
+static u64 notrace riscv_timer_get_count(struct udevice *dev)
 {
  __maybe_unused u32 hi, lo;
 
@@ -31,6 +31,25 @@ static u64 riscv_timer_get_count(struct udevice *dev)
  return ((u64)hi << 32) | lo;
 }
 
+#if CONFIG_IS_ENABLED(RISCV_SMODE) && IS_ENABLED(CONFIG_TIMER_EARLY)
+/**
+ * timer_early_get_rate() - Get the timer rate before driver model
+ */
+unsigned long notrace timer_early_get_rate(void)
+{
+ return RISCV_SMODE_TIMER_FREQ;
+}
+
+/**
+ * timer_early_get_count() - Get the timer count before driver model
+ *
+ */
+u64 notrace timer_early_get_count(void)
+{
+ return riscv_timer_get_count(NULL);
+}
+#endif
+
 static int riscv_timer_probe(struct udevice *dev)
 {
  struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
diff --git a/drivers/timer/sifive_clint_timer.c b/drivers/timer/sifive_clint_timer.c
index 00ce0f08d6..2e902feb61 100644
--- a/drivers/timer/sifive_clint_timer.c
+++ b/drivers/timer/sifive_clint_timer.c
@@ -14,11 +14,30 @@
 /* mtime register */
 #define MTIME_REG(base) ((ulong)(base) + 0xbff8)
 
-static u64 sifive_clint_get_count(struct udevice *dev)
+static u64 notrace sifive_clint_get_count(struct udevice *dev)
 {
  return readq((void __iomem *)MTIME_REG(dev->priv));
 }
 
+#if CONFIG_IS_ENABLED(RISCV_MMODE) && IS_ENABLED(CONFIG_TIMER_EARLY)
+/**
+ * timer_early_get_rate() - Get the timer rate before driver model
+ */
+unsigned long notrace timer_early_get_rate(void)
+{
+ return RISCV_MMODE_TIMER_FREQ;
+}
+
+/**
+ * timer_early_get_count() - Get the timer count before driver model
+ *
+ */
+u64 notrace timer_early_get_count(void)
+{
+ return readq((void __iomem *)MTIME_REG(RISCV_MMODE_TIMERBASE));
+}
+#endif
+
 static const struct timer_ops sifive_clint_ops = {
  .get_count = sifive_clint_get_count,
 };
diff --git a/include/configs/ax25-ae350.h b/include/configs/ax25-ae350.h
index b2606e794d..bd9c371f83 100644
--- a/include/configs/ax25-ae350.h
+++ b/include/configs/ax25-ae350.h
@@ -17,6 +17,11 @@
 #endif
 #endif
 
+#define RISCV_MMODE_TIMERBASE           0xe6000000
+#define RISCV_MMODE_TIMER_FREQ          60000000
+
+#define RISCV_SMODE_TIMER_FREQ          60000000
+
 /*
  * CPU and Board Configuration Options
  */
diff --git a/include/configs/qemu-riscv.h b/include/configs/qemu-riscv.h
index a2f33587c2..5291de83f8 100644
--- a/include/configs/qemu-riscv.h
+++ b/include/configs/qemu-riscv.h
@@ -29,6 +29,11 @@
 
 #define CONFIG_STANDALONE_LOAD_ADDR 0x80200000
 
+#define RISCV_MMODE_TIMERBASE 0x2000000
+#define RISCV_MMODE_TIMER_FREQ 1000000
+
+#define RISCV_SMODE_TIMER_FREQ 1000000
+
 /* Environment options */
 
 #ifndef CONFIG_SPL_BUILD
diff --git a/include/configs/sifive-fu540.h b/include/configs/sifive-fu540.h
index c1c79db147..0d69d1c548 100644
--- a/include/configs/sifive-fu540.h
+++ b/include/configs/sifive-fu540.h
@@ -36,6 +36,11 @@
 
 #define CONFIG_STANDALONE_LOAD_ADDR 0x80200000
 
+#define RISCV_MMODE_TIMERBASE 0x2000000
+#define RISCV_MMODE_TIMER_FREQ 1000000
+
+#define RISCV_SMODE_TIMER_FREQ 1000000
+
 /* Environment options */
 
 #ifndef CONFIG_SPL_BUILD
--
2.17.1

[Rick Chen]

> From: Pragnesh Patel [mailto:[hidden email]]
> Sent: Sunday, January 10, 2021 8:43 PM
> To: [hidden email]
> Cc: [hidden email]; [hidden email]; [hidden email]; [hidden email]; [hidden email]; [hidden email]; Rick Jian-Zhi Chen(陳建志); Pragnesh Patel; Palmer Dabbelt; Sean Anderson; Simon Glass
> Subject: [PATCH v3 2/2] riscv: timer: Add support for an early timer
>
> Added support for timer_early_get_count() and timer_early_get_rate()
> This is mostly useful in tracing.
>
> Signed-off-by: Pragnesh Patel <[hidden email]>
> ---
>
> Changes in v3:
> - Add IS_ENABLED(CONFIG_TIMER_EARLY) for timer_early_get_rate()
>   and timer_early_get_count() functions.

Reviewed-by: Rick Chen <[hidden email]>

[Rick Chen]

Hi Pragnesh

> > From: Pragnesh Patel [mailto:[hidden email]]
> > Sent: Sunday, January 10, 2021 8:43 PM
> > To: [hidden email]
> > Cc: [hidden email]; [hidden email]; [hidden email]; [hidden email]; [hidden email]; [hidden email]; Rick Jian-Zhi Chen(陳建志); Pragnesh Patel; Palmer Dabbelt; Sean Anderson; Simon Glass
> > Subject: [PATCH v3 2/2] riscv: timer: Add support for an early timer
> >
> > Added support for timer_early_get_count() and timer_early_get_rate()
> > This is mostly useful in tracing.
> >
> > Signed-off-by: Pragnesh Patel <[hidden email]>
> > ---
> >
> > Changes in v3:
> > - Add IS_ENABLED(CONFIG_TIMER_EARLY) for timer_early_get_rate()
> >   and timer_early_get_count() functions.
>
> Reviewed-by: Rick Chen <[hidden email]>

I am trying to merge to mainline, but it conflict with master.
Please rebase again,

Applying: trace: select TIMER_EARLY to avoid infinite recursion
Applying: riscv: timer: Add support for an early timer
error: patch failed: drivers/timer/andes_plmt_timer.c:17
error: drivers/timer/andes_plmt_timer.c: patch does not apply
error: patch failed: drivers/timer/sifive_clint_timer.c:14
error: drivers/timer/sifive_clint_timer.c: patch does not apply
Patch failed at 0002 riscv: timer: Add support for an early timer
The copy of the patch that failed is found in: .git/rebase-apply/patch
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

Thanks,
Rick