ARM: EXYNOS4: Suspend to RAM Support

This patch adds support suspend to ram for EXYNOS4210.
As a note, this includes function of outer cache flush
because it is used before entering PM.
Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-exynos4/Makefile

@@ -14,6 +14,7 @@ obj-				:=
 
 obj-$(CONFIG_CPU_EXYNOS4210)	+= cpu.o init.o clock.o irq-combiner.o
 obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o gpiolib.o irq-eint.o dma.o
+obj-$(CONFIG_PM)		+= pm.o sleep.o
 obj-$(CONFIG_CPU_FREQ)		+= cpufreq.o
 
 obj-$(CONFIG_SMP)		+= platsmp.o headsmp.o

arch/arm/mach-exynos4/include/mach/pm-core.h

+/* linux/arch/arm/mach-exynos4/include/mach/pm-core.h
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Based on arch/arm/mach-s3c2410/include/mach/pm-core.h,
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * EXYNOS4210 - PM core support for arch/arm/plat-s5p/pm.c
+ *
+ * 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 <mach/regs-pmu.h>
+
+static inline void s3c_pm_debug_init_uart(void)
+{
+	/* nothing here yet */
+}
+
+static inline void s3c_pm_arch_prepare_irqs(void)
+{
+	unsigned int tmp;
+	tmp = __raw_readl(S5P_WAKEUP_MASK);
+	tmp &= ~(1 << 31);
+	__raw_writel(tmp, S5P_WAKEUP_MASK);
+
+	__raw_writel(s3c_irqwake_intmask, S5P_WAKEUP_MASK);
+	__raw_writel(s3c_irqwake_eintmask, S5P_EINT_WAKEUP_MASK);
+}
+
+static inline void s3c_pm_arch_stop_clocks(void)
+{
+	/* nothing here yet */
+}
+
+static inline void s3c_pm_arch_show_resume_irqs(void)
+{
+	/* nothing here yet */
+}
+
+static inline void s3c_pm_arch_update_uart(void __iomem *regs,
+					   struct pm_uart_save *save)
+{
+	/* nothing here yet */
+}

arch/arm/mach-exynos4/sleep.S

+/* linux/arch/arm/mach-exynos4/sleep.S
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * EXYNOS4210 power Manager (Suspend-To-RAM) support
+ * Based on S3C2410 sleep code by:
+ *	Ben Dooks, (c) 2004 Simtec Electronics
+ *
+ * Based on PXA/SA1100 sleep code by:
+ *	Nicolas Pitre, (c) 2002 Monta Vista Software Inc
+ *	Cliff Brake, (c) 2001
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/memory.h>
+
+	.text
+
+	/*
+	 * s3c_cpu_save
+	 *
+	 * entry:
+	 *	r1 = v:p offset
+	 */
+
+ENTRY(s3c_cpu_save)
+
+	stmfd	sp!, { r3 - r12, lr }
+	ldr	r3, =resume_with_mmu
+	bl	cpu_suspend
+
+	ldr	r0, =pm_cpu_sleep
+	ldr	r0, [ r0 ]
+	mov	pc, r0
+
+resume_with_mmu:
+	ldmfd	sp!, { r3 - r12, pc }
+
+	.ltorg
+
+	/*
+	 * sleep magic, to allow the bootloader to check for an valid
+	 * image to resume to. Must be the first word before the
+	 * s3c_cpu_resume entry.
+	 */
+
+	.word	0x2bedf00d
+
+	/*
+	 * s3c_cpu_resume
+	 *
+	 * resume code entry for bootloader to call
+	 *
+	 * we must put this code here in the data segment as we have no
+	 * other way of restoring the stack pointer after sleep, and we
+	 * must not write to the code segment (code is read-only)
+	 */
+
+ENTRY(s3c_cpu_resume)
+	b	cpu_resume

arch/arm/plat-samsung/include/plat/cpu.h

@@ -82,6 +82,7 @@ extern struct sysdev_class s3c64xx_sysclass;
 extern struct sysdev_class s5p64x0_sysclass;
 extern struct sysdev_class s5p6442_sysclass;
 extern struct sysdev_class s5pv210_sysclass;
+extern struct sysdev_class exynos4_sysclass;
 
 extern void (*s5pc1xx_idle)(void);