On 27/08/13 12:21, Catalin Marinas wrote:
> On Fri, Aug 23, 2013 at 05:19:05PM +0100, Sudeep KarkadaNagesha wrote:
>> From: Sudeep KarkadaNagesha <sudeep.karkadanage...@arm.com>
>>
>> Add macros to describe the bitfields in the ARM architected timer
>> control register to make code easy to understand.
>>
>> Cc: Catalin Marinas <catalin.mari...@arm.com>
>> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieral...@arm.com>
>> Reviewed-by: Will Deacon <will.dea...@arm.com>
>> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanage...@arm.com>
>> ---
>> arch/arm/include/asm/arch_timer.h | 9 +++++++--
>> arch/arm64/include/asm/arch_timer.h | 12 ++++++++----
>> include/clocksource/arm_arch_timer.h | 8 ++++++++
>> 3 files changed, 23 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/arch_timer.h
>> b/arch/arm/include/asm/arch_timer.h
>> index e406d57..9ef74da 100644
>> --- a/arch/arm/include/asm/arch_timer.h
>> +++ b/arch/arm/include/asm/arch_timer.h
>> @@ -95,8 +95,13 @@ static inline void arch_counter_set_user_access(void)
>>
>> asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
>>
>> - /* disable user access to everything */
>> - cntkctl &= ~((3 << 8) | (7 << 0));
>> + /* Disable user access to both physical/virtual counters/timers. */
>> + /* Also disable virtual event stream */
>> + cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
>> + | ARCH_TIMER_USR_VT_ACCESS_EN
>> + | ARCH_TIMER_VIRT_EVT_EN
>> + | ARCH_TIMER_USR_VCT_ACCESS_EN
>> + | ARCH_TIMER_USR_PCT_ACCESS_EN);
>>
>> asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
>> }
>> diff --git a/arch/arm64/include/asm/arch_timer.h
>> b/arch/arm64/include/asm/arch_timer.h
>> index 98abd47..00b09d0 100644
>> --- a/arch/arm64/include/asm/arch_timer.h
>> +++ b/arch/arm64/include/asm/arch_timer.h
>> @@ -101,12 +101,16 @@ static inline void arch_counter_set_user_access(void)
>> {
>> u32 cntkctl;
>>
>> - /* Disable user access to the timers and the physical counter. */
>> asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
>> - cntkctl &= ~((3 << 8) | (1 << 0));
>>
>> - /* Enable user access to the virtual counter and frequency. */
>> - cntkctl |= (1 << 1);
>> + /* Disable user access to the timers and the physical counter. */
>> + cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
>> + | ARCH_TIMER_USR_VT_ACCESS_EN
>> + | ARCH_TIMER_USR_PCT_ACCESS_EN);
>> +
>> + /* Enable user access to the virtual counter. */
>> + cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;
>> +
>> asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
>
> For consistency with arm, I think we should also disable the event
> stream explicitly here.
>
Yes it's done. In PATCH 3/5, a new function arch_timer_evtstrm_config is
added which is always called(PATCH 4/5). It's either enabled or disabled
explicitly based on config option for event stream.
Let me know if you think that's not sufficient.
Regards,
Sudeep
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