Some msm targets have timers whose lower bits are unreliable. So, we
present our timers as lower frequency than they actually are, and ignore
the bottom 5 bits on such targets. This compensation was erroneously
removed from the msm_read_timer_count function, so restore it.
This was broken by 94790ec25 "msm: timer: SMP timer support for msm".
Change-Id: I8c56bdf82629638748ccf352118ea664f967b87d
Signed-off-by: Jeff Ohlstein <[email protected]>
---
arch/arm/mach-msm/timer.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
index 38b95e9..b3579fe 100644
--- a/arch/arm/mach-msm/timer.c
+++ b/arch/arm/mach-msm/timer.c
@@ -100,7 +100,7 @@ static cycle_t msm_read_timer_count(struct clocksource *cs)
{
struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource);
- return readl(clk->global_counter);
+ return readl(clk->global_counter) >> clk->shift;
}
static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt)
--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
On Wed, 2011-06-08 at 20:44 -0700, Jeff Ohlstein wrote:
> Some msm targets have timers whose lower bits are unreliable. So, we
> present our timers as lower frequency than they actually are, and ignore
> the bottom 5 bits on such targets. This compensation was erroneously
> removed from the msm_read_timer_count function, so restore it.
>
> This was broken by 94790ec25 "msm: timer: SMP timer support for msm".
>
> Change-Id: I8c56bdf82629638748ccf352118ea664f967b87d
Drop this Change-ID ..
> Signed-off-by: Jeff Ohlstein <[email protected]>
> ---
> arch/arm/mach-msm/timer.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
> index 38b95e9..b3579fe 100644
> --- a/arch/arm/mach-msm/timer.c
> +++ b/arch/arm/mach-msm/timer.c
> @@ -100,7 +100,7 @@ static cycle_t msm_read_timer_count(struct clocksource *cs)
> {
> struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource);
>
> - return readl(clk->global_counter);
> + return readl(clk->global_counter) >> clk->shift;
> }
Could you comment in the code with something explaining what the shift
is doing.
Daniel
On Thu, Jun 09 2011, Daniel Walker wrote:
>> diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
>> index 38b95e9..b3579fe 100644
>> --- a/arch/arm/mach-msm/timer.c
>> +++ b/arch/arm/mach-msm/timer.c
>> @@ -100,7 +100,7 @@ static cycle_t msm_read_timer_count(struct clocksource *cs)
>> {
>> struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource);
>>
>> - return readl(clk->global_counter);
>> + return readl(clk->global_counter) >> clk->shift;
>> }
>
> Could you comment in the code with something explaining what the shift
> is doing.
Probably best to describe this near msm_clock's definition (or
MSM_DGT_SHIFT), since it is a bit unclear what these values are.
A good (but short) description of how the shifts and even why.
The comment shouldn't be in the function body (CodingStyle, chapter 8).
David
--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.