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

From: [email-masked] (Tomasz Figa)
Date: Fri, 24 Aug 2012 19:15:51 +0200

Hello,

Please see my comments inline.

On Friday 24 of August 2012 17:33:57 Kyungmin Park wrote:
> From: Kyungmin Park <[email-masked]>
> 
> Some boards, e.g., exynos4412, can use smc instruction (aka firmware)
> interally.
> 
> Signed-off-by: Kyungmin Park <[email-masked]>
> ---
> Changelog v4
> 	use call_firmware_op instead of indirect call
> 
> 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)
> +
>  # machine support
> 
>  obj-$(CONFIG_MACH_SMDKC210)		+= mach-smdkv310.o
> diff --git a/arch/arm/mach-exynos/common.h
> b/arch/arm/mach-exynos/common.h index aed2eeb..540918f 100644
> --- a/arch/arm/mach-exynos/common.h
> +++ b/arch/arm/mach-exynos/common.h
> @@ -21,6 +21,8 @@ void exynos4_restart(char mode, const char *cmd);
>  void exynos5_restart(char mode, const char *cmd);
>  void exynos_init_late(void);
> 
> +void exynos_firmware_init(void);
> +
>  #ifdef CONFIG_PM_GENERIC_DOMAINS
>  int exynos_pm_late_initcall(void);
>  #else
> diff --git a/arch/arm/mach-exynos/exynos-smc.S
> b/arch/arm/mach-exynos/exynos-smc.S new file mode 100644
> index 0000000..2e27aa3
> --- /dev/null
> +++ b/arch/arm/mach-exynos/exynos-smc.S
> @@ -0,0 +1,22 @@
> +/*
> + * Copyright (C) 2012 Samsung Electronics.
> + *
> + * Copied from omap-smc.S Copyright (C) 2010 Texas Instruments, Inc.
> + *
> + * 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/linkage.h>
> +
> +/*
> + * Function signature: void exynos_smc(u32 cmd, u32 arg1, u32 arg2, u32
> arg3) + */
> +
> +ENTRY(exynos_smc)
> +	stmfd	sp!, {r4-r11, lr}
> +	dsb
> +	smc	#0
> +	ldmfd	sp!, {r4-r11, pc}
> +ENDPROC(exynos_smc)
> 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;
> +}
> diff --git a/arch/arm/mach-exynos/platsmp.c
> b/arch/arm/mach-exynos/platsmp.c index 36c3984..c664a86 100644
> --- a/arch/arm/mach-exynos/platsmp.c
> +++ b/arch/arm/mach-exynos/platsmp.c
> @@ -25,6 +25,7 @@
>  #include <asm/hardware/gic.h>
>  #include <asm/smp_plat.h>
>  #include <asm/smp_scu.h>
> +#include <asm/firmware.h>
> 
>  #include <mach/hardware.h>
>  #include <mach/regs-clock.h>
> @@ -139,6 +140,12 @@ int __cpuinit boot_secondary(unsigned int cpu,
> struct task_struct *idle)
> 
>  		__raw_writel(virt_to_phys(exynos4_secondary_startup),
>  			CPU1_BOOT_REG);
> +
> +		if (IS_ENABLED(CONFIG_ARM_FIRMWARE)) {
> +			/* Call Exynos specific smc call */
> +			call_firmware_op(cpu_boot, cpu);
> +		}

We don't need to check IS_ENABLED(CONFIG_ARM_FIRMWARE) now as 
call_firmware_op does it for us.

--
Best regards,
Tomasz Figa

> +
>  		gic_raise_softirq(cpumask_of(cpu), 1);
> 
>  		if (pen_release == -1)
> diff --git a/arch/arm/mach-exynos/smc.h b/arch/arm/mach-exynos/smc.h
> new file mode 100644
> index 0000000..e972390
> --- /dev/null
> +++ b/arch/arm/mach-exynos/smc.h
> @@ -0,0 +1,31 @@
> +/*
> + *  Copyright (c) 2012 Samsung Electronics.
> + *
> + * EXYNOS - SMC Call
> + *
> + * 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.
> + */
> +
> +#ifndef __ASM_ARCH_EXYNOS_SMC_H
> +#define __ASM_ARCH_EXYNOS_SMC_H
> +
> +#define SMC_CMD_INIT            (-1)
> +#define SMC_CMD_INFO            (-2)
> +/* For Power Management */
> +#define SMC_CMD_SLEEP           (-3)
> +#define SMC_CMD_CPU1BOOT        (-4)
> +#define SMC_CMD_CPU0AFTR        (-5)
> +/* For CP15 Access */
> +#define SMC_CMD_C15RESUME       (-11)
> +/* For L2 Cache Access */
> +#define SMC_CMD_L2X0CTRL        (-21)
> +#define SMC_CMD_L2X0SETUP1      (-22)
> +#define SMC_CMD_L2X0SETUP2      (-23)
> +#define SMC_CMD_L2X0INVALL      (-24)
> +#define SMC_CMD_L2X0DEBUG       (-25)
> +
> +extern void exynos_smc(u32 cmd, u32 arg1, u32 arg2, u32 arg3);
> +
> +#endif
> 
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