diff mbox

[U-Boot] arm: armv7: add us timer for bootstage

Message ID 1479832293-9377-1-git-send-email-patrick.delaunay73@gmail.com
State Accepted
Commit 91558c815391a4cdc8c8bd57f5c25b319af0bb80
Delegated to: Tom Rini
Headers show

Commit Message

Patrick Delaunay Nov. 22, 2016, 4:31 p.m. UTC 
From: Patrick Delaunay <patrick.delaunay@st.com>

solve issue when bootstage is used with armV7 generic timer
first call of timer_get_boot_us() use the function get_timer()
before timer initialization (arch.timer_rate_hz = 0)
=> div by 0

Commit-notes

When I activate bootstage on ARMV7 architecture with platform
using the generic armv7 timer defined in file
./arch/arm/cpu/armv7m/timer.c

I have a issue because gd->arch.timer_rate_hz = 0

For me the get_timer() function should not used before timer_init
(which initialize gd->arch.timer_rate_hz) at least for the ARMV7
timer.

But in the init sequence, the first bootstage fucntion is called
before timer_init and this function use the timer function.

For me it is a error in the generic init sequence :
mark_bootstage is called before timer_init.

static init_fnc_t init_sequence_f[] = {
....
    arch_cpu_init_dm,
    mark_bootstage,        /* need timer, go after init dm */
...
#if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || \
        defined(CONFIG_BLACKFIN) || defined(CONFIG_NDS32) || \
        defined(CONFIG_SPARC)
    timer_init,        /* initialize timer */
#endif
.......

To solve the issue for all the paltform, we can move timer_init()
call just before mark_bootstage() in this array...

It should be ok for ARMV7 but I don't sure for other platform
impacted
- the other ARM platform or ARMV7 wich don't use generic timer
- MIPS BLACKFIN NDS32 or SPARC

and I don't sure of impact for other function called
(board_early_init_f for example....)

=> This patch solve issue only in timer armv7
   get_boot_us() can be called everytime without div by 0 issue
   (gd->arch.timer_rate_hz is not used)

END

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay73@gmail.com>
---

 arch/arm/cpu/armv7/arch_timer.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Comments

Tom Rini Dec. 12, 2016, 1:32 p.m. UTC | #1 
On Tue, Nov 22, 2016 at 05:31:33PM +0100, Patrick Delaunay wrote:

> From: Patrick Delaunay <patrick.delaunay@st.com>
> 
> solve issue when bootstage is used with armV7 generic timer
> first call of timer_get_boot_us() use the function get_timer()
> before timer initialization (arch.timer_rate_hz = 0)
> => div by 0
> 
> Commit-notes
> 
> When I activate bootstage on ARMV7 architecture with platform
> using the generic armv7 timer defined in file
> ./arch/arm/cpu/armv7m/timer.c
> 
> I have a issue because gd->arch.timer_rate_hz = 0
> 
> For me the get_timer() function should not used before timer_init
> (which initialize gd->arch.timer_rate_hz) at least for the ARMV7
> timer.
> 
> But in the init sequence, the first bootstage fucntion is called
> before timer_init and this function use the timer function.
> 
> For me it is a error in the generic init sequence :
> mark_bootstage is called before timer_init.
> 
> static init_fnc_t init_sequence_f[] = {
> ....
>     arch_cpu_init_dm,
>     mark_bootstage,        /* need timer, go after init dm */
> ...
> #if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || \
>         defined(CONFIG_BLACKFIN) || defined(CONFIG_NDS32) || \
>         defined(CONFIG_SPARC)
>     timer_init,        /* initialize timer */
> #endif
> .......
> 
> To solve the issue for all the paltform, we can move timer_init()
> call just before mark_bootstage() in this array...
> 
> It should be ok for ARMV7 but I don't sure for other platform
> impacted
> - the other ARM platform or ARMV7 wich don't use generic timer
> - MIPS BLACKFIN NDS32 or SPARC
> 
> and I don't sure of impact for other function called
> (board_early_init_f for example....)
> 
> => This patch solve issue only in timer armv7
>    get_boot_us() can be called everytime without div by 0 issue
>    (gd->arch.timer_rate_hz is not used)
> 
> END
> 
> Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
> Signed-off-by: Patrick Delaunay <patrick.delaunay73@gmail.com>

Applied to u-boot/master, thanks!
diff mbox

Patch

diff --git a/arch/arm/cpu/armv7/arch_timer.c b/arch/arm/cpu/armv7/arch_timer.c
index 0588e2b..30915d2 100644
--- a/arch/arm/cpu/armv7/arch_timer.c
+++ b/arch/arm/cpu/armv7/arch_timer.c
@@ -8,6 +8,7 @@ 
 #include <common.h>
 #include <asm/io.h>
 #include <div64.h>
+#include <bootstage.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -17,7 +18,6 @@  int timer_init(void)
 	gd->arch.tbu = 0;
 
 	gd->arch.timer_rate_hz = CONFIG_SYS_HZ_CLOCK / CONFIG_SYS_HZ;
-
 	return 0;
 }
 
@@ -39,6 +39,11 @@  ulong get_timer(ulong base)
 	return lldiv(get_ticks(), gd->arch.timer_rate_hz) - base;
 }
 
+ulong timer_get_boot_us(void)
+{
+	return lldiv(get_ticks(), CONFIG_SYS_HZ_CLOCK / (CONFIG_SYS_HZ * 1000));
+}
+
 void __udelay(unsigned long usec)
 {
 	unsigned long long endtime;