Subject: [PATCH v6 01/10] clocksource: arm_arch_timer: Gather KVM specific information in a structure

From: [email-masked] (Shanker Donthineni)
Date: Sat, 23 Apr 2016 21:54:53 -0500

On 04/11/2016 10:32 AM, Julien Grall wrote:
> Introduce a structure which are filled up by the arch timer driver and
> used by the virtual timer in KVM.
>
> The first member of this structure will be the timecounter. More members
> will be added later.
>
> A stub for the new helper isn't introduced because KVM requires the arch
> timer for both ARM64 and ARM32.
>
> The function arch_timer_get_timecounter is kept for the time being and
> will be dropped in a subsequent patch.
>
> Signed-off-by: Julien Grall <[email-masked]>
> Acked-by: Christoffer Dall <[email-masked]>
>
Tested-by: Shanker Donthineni <[email-masked]>

Using the Qualcomm Technologies QDF2XXX server platform.
> ---
> Cc: Daniel Lezcano <[email-masked]>
> Cc: Thomas Gleixner <[email-masked]>
> Cc: Marc Zyngier <[email-masked]>
>
>     Changes in v6:
>         - Add Christoffer's acked-by
>
>     Changes in v3:
>         - Rename the patch
>         - Move the KVM changes and removal of arch_timer_get_timecounter
>         in separate patches.
> ---
>  drivers/clocksource/arm_arch_timer.c | 12 +++++++++---
>  include/clocksource/arm_arch_timer.h |  5 +++++
>  2 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clocksource/arm_arch_timer.c
> b/drivers/clocksource/arm_arch_timer.c
> index 5152b38..62bdfe7 100644
> --- a/drivers/clocksource/arm_arch_timer.c
> +++ b/drivers/clocksource/arm_arch_timer.c
> @@ -468,11 +468,16 @@ static struct cyclecounter cyclecounter = {
>  	.mask	= CLOCKSOURCE_MASK(56),
>  };
>  
> -static struct timecounter timecounter;
> +static struct arch_timer_kvm_info arch_timer_kvm_info;
> +
> +struct arch_timer_kvm_info *arch_timer_get_kvm_info(void)
> +{
> +	return &arch_timer_kvm_info;
> +}
>  
>  struct timecounter *arch_timer_get_timecounter(void)
>  {
> -	return &timecounter;
> +	return &arch_timer_kvm_info.timecounter;
>  }
>  
>  static void __init arch_counter_register(unsigned type)
> @@ -500,7 +505,8 @@ static void __init arch_counter_register(unsigned
> type)
>  	clocksource_register_hz(&clocksource_counter, arch_timer_rate);
>  	cyclecounter.mult = clocksource_counter.mult;
>  	cyclecounter.shift = clocksource_counter.shift;
> -	timecounter_init(&timecounter, &cyclecounter, start_count);
> +	timecounter_init(&arch_timer_kvm_info.timecounter,
> +			 &cyclecounter, start_count);
>  
>  	/* 56 bits minimum, so we assume worst case rollover */
>  	sched_clock_register(arch_timer_read_counter, 56,
> arch_timer_rate);
> diff --git a/include/clocksource/arm_arch_timer.h
> b/include/clocksource/arm_arch_timer.h
> index 25d0914..9101ed6b 100644
> --- a/include/clocksource/arm_arch_timer.h
> +++ b/include/clocksource/arm_arch_timer.h
> @@ -49,11 +49,16 @@ enum arch_timer_reg {
>  
>  #define ARCH_TIMER_EVT_STREAM_FREQ	10000	/* 100us */
>  
> +struct arch_timer_kvm_info {
> +	struct timecounter timecounter;
> +};
> +
>  #ifdef CONFIG_ARM_ARCH_TIMER
>  
>  extern u32 arch_timer_get_rate(void);
>  extern u64 (*arch_timer_read_counter)(void);
>  extern struct timecounter *arch_timer_get_timecounter(void);
> +extern struct arch_timer_kvm_info *arch_timer_get_kvm_info(void);
>  
>  #else
>  

-- 
Shanker Donthineni
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project