lkml.org 
[lkml]   [2014]   [Aug]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 8/9] ARM: zynq: Remove hotplug.c
On 08/20/2014 10:41 PM, Soren Brinkmann wrote:
> The hotplug code contains only a single function, which is an SMP
> function. Move that to platsmp.c where all other SMP runctions reside.
> That allows removing hotplug.c and declaring the cpu_die function
> static.
>
> Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
> ---
> arch/arm/mach-zynq/Makefile | 1 -
> arch/arm/mach-zynq/common.h | 3 +--
> arch/arm/mach-zynq/hotplug.c | 17 -----------------
> arch/arm/mach-zynq/platsmp.c | 18 ++++++++++++++++++
> 4 files changed, 19 insertions(+), 20 deletions(-)
>
> diff --git a/arch/arm/mach-zynq/Makefile b/arch/arm/mach-zynq/Makefile
> index 820dff6e1eba..c85fb3f7d5cd 100644
> --- a/arch/arm/mach-zynq/Makefile
> +++ b/arch/arm/mach-zynq/Makefile
> @@ -6,5 +6,4 @@
> obj-y := common.o slcr.o pm.o
> CFLAGS_REMOVE_hotplug.o =-march=armv6k
> CFLAGS_hotplug.o =-Wa,-march=armv7-a -mcpu=cortex-a9
> -obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
> obj-$(CONFIG_SMP) += headsmp.o platsmp.o
> diff --git a/arch/arm/mach-zynq/common.h b/arch/arm/mach-zynq/common.h
> index c0773e87e83c..e6bb12c50a23 100644
> --- a/arch/arm/mach-zynq/common.h
> +++ b/arch/arm/mach-zynq/common.h
> @@ -39,8 +39,7 @@ extern struct smp_operations zynq_smp_ops __initdata;
>
> extern void __iomem *zynq_scu_base;
>
> -/* Hotplug */
> -extern void zynq_platform_cpu_die(unsigned int cpu);
> +int zynq_pm_late_init(void);
>
> int zynq_pm_late_init(void);
>
> diff --git a/arch/arm/mach-zynq/hotplug.c b/arch/arm/mach-zynq/hotplug.c
> index fe44a05677e2..b685c89f11e4 100644
> --- a/arch/arm/mach-zynq/hotplug.c
> +++ b/arch/arm/mach-zynq/hotplug.c
> @@ -12,20 +12,3 @@
> */
> #include <asm/proc-fns.h>
>
> -/*
> - * platform-specific code to shutdown a CPU
> - *
> - * Called with IRQs disabled
> - */
> -void zynq_platform_cpu_die(unsigned int cpu)
> -{
> - zynq_slcr_cpu_state_write(cpu, true);
> -
> - /*
> - * there is no power-control hardware on this platform, so all
> - * we can do is put the core into WFI; this is safe as the calling
> - * code will have already disabled interrupts
> - */
> - for (;;)
> - cpu_do_idle();
> -}
> diff --git a/arch/arm/mach-zynq/platsmp.c b/arch/arm/mach-zynq/platsmp.c
> index f77f7ca4c45b..04e578718aa2 100644
> --- a/arch/arm/mach-zynq/platsmp.c
> +++ b/arch/arm/mach-zynq/platsmp.c
> @@ -132,6 +132,24 @@ static int zynq_cpu_kill(unsigned cpu)
> zynq_slcr_cpu_stop(cpu);
> return 1;
> }
> +
> +/*
> + * platform-specific code to shutdown a CPU
> + *
> + * Called with IRQs disabled
> + */
> +static void zynq_platform_cpu_die(unsigned int cpu)
> +{
> + zynq_slcr_cpu_state_write(cpu, true);
> +
> + /*
> + * there is no power-control hardware on this platform, so all
> + * we can do is put the core into WFI; this is safe as the calling
> + * code will have already disabled interrupts
> + */
> + for (;;)
> + cpu_do_idle();

IIUC, the cpu_do_idle() will flush the L1 cache and then call the WFI.
It makes sense if we are about to power down the core. So I am wondering
if we can just call wfi() instead.

> +}
> #endif
>
> struct smp_operations zynq_smp_ops __initdata = {
>


--
<http://www.linaro.org/> Linaro.org │ 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@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2014-08-21 03:41    [W:0.099 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site