[PATCH V2] ARM: EXYNOS: cpu hotplug: use v7_exit_coherency_flush macro for cache disabling
Chanwoo Choi
cw00.choi at samsung.com
Wed Apr 30 01:02:13 PDT 2014
Hi,
On 04/23/2014 02:52 PM, Leela Krishna Amudala wrote:
> A common macro v7_exit_coherency_flush available which does the below tasks in
> the seqeunce.
> -clearing C bit
> -clearing L1 cache
> -exit SMP
> -instruction and data synchronization
>
> So removing the local functions which does the same thing and use the macro instead.
>
> Signed-off-by: Leela Krishna Amudala <leela.krishna at linaro.org>
> Acked-by: Nicolas Pitre <nico at linaro.org>
> ---
> Changes since V1:
> - removed unwanted primary_part variable in exynos_cpu_die()
> - given more description in commit message
> suggested by Daniel Lezcano <daniel.lezcano at linaro.org>
>
> arch/arm/mach-exynos/hotplug.c | 63 +---------------------------------------
> 1 file changed, 1 insertion(+), 62 deletions(-)
>
> diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
> index 5eead53..9ca692d 100644
> --- a/arch/arm/mach-exynos/hotplug.c
> +++ b/arch/arm/mach-exynos/hotplug.c
> @@ -24,56 +24,6 @@
> #include "common.h"
> #include "regs-pmu.h"
>
> -static inline void cpu_enter_lowpower_a9(void)
> -{
> - unsigned int v;
> -
> - asm volatile(
> - " mcr p15, 0, %1, c7, c5, 0\n"
> - " mcr p15, 0, %1, c7, c10, 4\n"
> - /*
> - * Turn off coherency
> - */
> - " mrc p15, 0, %0, c1, c0, 1\n"
> - " bic %0, %0, %3\n"
> - " mcr p15, 0, %0, c1, c0, 1\n"
> - " mrc p15, 0, %0, c1, c0, 0\n"
> - " bic %0, %0, %2\n"
> - " mcr p15, 0, %0, c1, c0, 0\n"
> - : "=&r" (v)
> - : "r" (0), "Ir" (CR_C), "Ir" (0x40)
> - : "cc");
> -}
> -
> -static inline void cpu_enter_lowpower_a15(void)
> -{
> - unsigned int v;
> -
> - asm volatile(
> - " mrc p15, 0, %0, c1, c0, 0\n"
> - " bic %0, %0, %1\n"
> - " mcr p15, 0, %0, c1, c0, 0\n"
> - : "=&r" (v)
> - : "Ir" (CR_C)
> - : "cc");
> -
> - flush_cache_louis();
> -
> - asm volatile(
> - /*
> - * Turn off coherency
> - */
> - " mrc p15, 0, %0, c1, c0, 1\n"
> - " bic %0, %0, %1\n"
> - " mcr p15, 0, %0, c1, c0, 1\n"
> - : "=&r" (v)
> - : "Ir" (0x40)
> - : "cc");
> -
> - isb();
> - dsb();
> -}
> -
> static inline void cpu_leave_lowpower(void)
> {
> unsigned int v;
> @@ -132,19 +82,8 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
> void __ref exynos_cpu_die(unsigned int cpu)
> {
> int spurious = 0;
> - int primary_part = 0;
>
> - /*
> - * we're ready for shutdown now, so do it.
> - * Exynos4 is A9 based while Exynos5 is A15; check the CPU part
> - * number by reading the Main ID register and then perform the
> - * appropriate sequence for entering low power.
> - */
> - asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");
> - if ((primary_part & 0xfff0) == 0xc0f0)
> - cpu_enter_lowpower_a15();
> - else
> - cpu_enter_lowpower_a9();
> + v7_exit_coherency_flush(louis);
>
> platform_do_lowpower(cpu, &spurious);
>
>
I tested this patch on Exynos3250 based on Cortex-A7 dual core.
Tested-by: Chanwoo Choi <cw00.choi at samsung.com>
Thanks,
Chanwoo Choi
More information about the linux-arm-kernel
mailing list