Subject: [PATCH v5 2/2] ARM: EXYNOS: SMC instruction (aka firmware) support

From: [email-masked] (Olof Johansson)
Date: Mon, 27 Aug 2012 15:10:30 -0700

Hi,

See below.

On Fri, Aug 24, 2012 at 05:33:57PM +0900, Kyungmin Park wrote:

> diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile
> index 9b58024..8ee779c 100644
> --- a/arch/arm/mach-exynos/Makefile
> +++ b/arch/arm/mach-exynos/Makefile
> @@ -30,6 +30,11 @@ obj-$(CONFIG_EXYNOS4_MCT)	+= mct.o
>  
>  obj-$(CONFIG_HOTPLUG_CPU)	+= hotplug.o
>  
> +obj-$(CONFIG_ARM_FIRMWARE)	+= exynos-smc.o firmware.o
> +
> +plus_sec := $(call as-instr,.arch_extension sec,+sec)
> +AFLAGS_exynos-smc.o		:=-Wa,-march=armv7-a$(plus_sec)

Again, no need for a config option here.

> diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
> new file mode 100644
> index 0000000..a144593
> --- /dev/null
> +++ b/arch/arm/mach-exynos/firmware.c
> @@ -0,0 +1,37 @@
> +/*
> + *  Copyright (C) 2012 Samsung Electronics.
> + *  Kyungmin Park <[email-masked]>
> + *
> + * This program is free software,you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +
> +#include <asm/firmware.h>
> +
> +#include "smc.h"
> +
> +static int exynos_do_idle(void)
> +{
> +        exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
> +        return 0;
> +}
> +
> +static void exynos_cpu_boot(int cpu)
> +{
> +	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
> +}
> +
> +static struct firmware_ops exynos_firmware_ops __initdata = {
> +	.do_idle	= exynos_do_idle,
> +	.cpu_boot	= exynos_cpu_boot,
> +};
> +
> +int __init exynos_firmware_init(void)
> +{
> +	firmware_ops = exynos_firmware_ops;
> +	return 0;
> +}

If you add a check for SMC presence/execution mode here, then you can
make this a runtime instead of boot time option, thus making it possible
to build a kernel that boots and runs both with and without SMC support.

-Olof