From: Emanuele Ghidoli <[email protected]>
imx_gpcv2_init() calls udelay(), which through schedule() reaches
cyclic_run(). Since commit 9c1b13b3fd27 ("cyclic: reduce get_timer_us()
calls inside hlist_for_each_entry_safe()") get_timer_us() is called even
when no cyclic function is registered, so tick_to_time_us() divides by a
still zero CNTFRQ and __div0() hangs the board before the console is up.
The requested delay was a no-op as well, since us_to_tick() reads a CNTFRQ
of zero.
Initialize the system counter before imx_gpcv2_init(), and move the
"already initialized" guard from timer_get_boot_us() into timer_init() so
that the later timer_init() from the generic init sequence is a no-op.
Where the system counter timer_init() is not compiled in, the weak
definition is empty and the calling it is harmless.
Fixes: b059837850e4 ("imx: mx7: add gpc initialization for low power mode")
Fixes: 9c1b13b3fd27 ("cyclic: reduce get_timer_us() calls inside
hlist_for_each_entry_safe()")
Signed-off-by: Emanuele Ghidoli <[email protected]>
---
arch/arm/mach-imx/mx7/soc.c | 6 ++++++
arch/arm/mach-imx/syscounter.c | 6 ++++--
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-imx/mx7/soc.c b/arch/arm/mach-imx/mx7/soc.c
index e504c1fd52a0..8a858dea5187 100644
--- a/arch/arm/mach-imx/mx7/soc.c
+++ b/arch/arm/mach-imx/mx7/soc.c
@@ -331,6 +331,12 @@ int arch_cpu_init(void)
init_snvs();
+ /*
+ * imx_gpcv2_init() needs to do a delay.
+ * Timer must be initialized before calling a delay function.
+ */
+ timer_init();
+
imx_gpcv2_init();
enable_ca7_smp();
diff --git a/arch/arm/mach-imx/syscounter.c b/arch/arm/mach-imx/syscounter.c
index 96fe2c7c17bb..86311d0cc07d 100644
--- a/arch/arm/mach-imx/syscounter.c
+++ b/arch/arm/mach-imx/syscounter.c
@@ -65,6 +65,9 @@ int timer_init(void)
struct sctr_regs *sctr = (struct sctr_regs *)SCTR_BASE_ADDR;
unsigned long val, freq;
+ if (gd->arch.timer_rate_hz)
+ return 0;
+
freq = CFG_SC_TIMER_CLK;
asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
@@ -103,8 +106,7 @@ ulong get_timer(ulong base)
ulong timer_get_boot_us(void)
{
- if (!gd->arch.timer_rate_hz)
- timer_init();
+ timer_init();
return tick_to_time(get_ticks());
}
--
2.43.0
