Re: [PATCH v3 1/6] ARM/ARM64: arch_timer: add macros for bits incontrol register

From: Daniel Lezcano
Date: Wed Aug 14 2013 - 05:23:33 EST


On 08/14/2013 11:03 AM, Marc Zyngier wrote:
> Hi Daniel,

[ ... ]

>>> --- 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));
>>> }
>>
>> Before doing those changes, I suggest you kill include/asm/arch_timer.h
>> header file and move the functions directly in the arm_arch_timer.c as
>> they are only used by it.
>
> How do you suggest to proceed? Having #ifdefs in arm_arch_timer.c to
> cope with the inline assembly functions present in both arm and arm64
> include files? Doesn't seem much of a progress to me...

I understand, this is arguable.

--
<http://www.linaro.org/> Linaro.org â Open source software for ARM SoCs

Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/