ARM: EXYNOS4: Implement kernel timers using MCT

The Multi-Core Timer(MCT) of EXYNOS4 is designed for implementing
clock source timer and clock event timers. This patch implements
1 clock source timer with 64 bit free running counter of MCT and
2 clock event timers with two of 31-bit tick counters.
Signed-off-by: Changhwan Youn <chaos.youn@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/Kconfig

@@ -1366,7 +1366,7 @@ config LOCAL_TIMERS
 	bool "Use local timer interrupts"
 	depends on SMP
 	default y
-	select HAVE_ARM_TWD if !ARCH_MSM_SCORPIONMP
+	select HAVE_ARM_TWD if (!ARCH_MSM_SCORPIONMP && !EXYNOS4_MCT)
 	help
 	  Enable support for local timers on SMP platforms, rather then the
 	  legacy IPI broadcast method.  Local timers allows the system

arch/arm/mach-exynos4/Kconfig

@@ -15,6 +15,11 @@ config CPU_EXYNOS4210
 	help
 	  Enable EXYNOS4210 CPU support
 
+config EXYNOS4_MCT
+	bool "Kernel timer support by MCT"
+	help
+	  Use MCT (Multi Core Timer) as kernel timers
+
 config EXYNOS4_DEV_PD
 	bool
 	help

arch/arm/mach-exynos4/Makefile

@@ -13,11 +13,18 @@ obj-				:=
 # Core support for EXYNOS4 system
 
 obj-$(CONFIG_CPU_EXYNOS4210)	+= cpu.o init.o clock.o irq-combiner.o
-obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o time.o gpiolib.o irq-eint.o dma.o
+obj-$(CONFIG_CPU_EXYNOS4210)	+= setup-i2c0.o gpiolib.o irq-eint.o dma.o
 obj-$(CONFIG_CPU_FREQ)		+= cpufreq.o
 
 obj-$(CONFIG_SMP)		+= platsmp.o headsmp.o
+
+ifeq ($(CONFIG_EXYNOS4_MCT),y)
+obj-y				+= mct.o
+else
+obj-y				+= time.o
 obj-$(CONFIG_LOCAL_TIMERS)	+= localtimer.o
+endif
+
 obj-$(CONFIG_HOTPLUG_CPU)	+= hotplug.o
 
 # machine support

arch/arm/mach-exynos4/include/mach/regs-mct.h

+/* arch/arm/mach-exynos4/include/mach/regs-mct.h
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * EXYNOS4 MCT configutation
+ *
+ * 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_REGS_MCT_H
+#define __ASM_ARCH_REGS_MCT_H __FILE__
+
+#include <mach/map.h>
+
+#define EXYNOS4_MCTREG(x)		(S5P_VA_SYSTIMER + (x))
+
+#define EXYNOS4_MCT_G_CNT_L		EXYNOS4_MCTREG(0x100)
+#define EXYNOS4_MCT_G_CNT_U		EXYNOS4_MCTREG(0x104)
+#define EXYNOS4_MCT_G_CNT_WSTAT		EXYNOS4_MCTREG(0x110)
+
+#define EXYNOS4_MCT_G_COMP0_L		EXYNOS4_MCTREG(0x200)
+#define EXYNOS4_MCT_G_COMP0_U		EXYNOS4_MCTREG(0x204)
+#define EXYNOS4_MCT_G_COMP0_ADD_INCR	EXYNOS4_MCTREG(0x208)
+
+#define EXYNOS4_MCT_G_TCON		EXYNOS4_MCTREG(0x240)
+
+#define EXYNOS4_MCT_G_INT_CSTAT		EXYNOS4_MCTREG(0x244)
+#define EXYNOS4_MCT_G_INT_ENB		EXYNOS4_MCTREG(0x248)
+#define EXYNOS4_MCT_G_WSTAT		EXYNOS4_MCTREG(0x24C)
+
+#define EXYNOS4_MCT_L0_BASE		EXYNOS4_MCTREG(0x300)
+#define EXYNOS4_MCT_L1_BASE		EXYNOS4_MCTREG(0x400)
+
+#define MCT_L_TCNTB_OFFSET		(0x00)
+#define MCT_L_ICNTB_OFFSET		(0x08)
+#define MCT_L_TCON_OFFSET		(0x20)
+#define MCT_L_INT_CSTAT_OFFSET		(0x30)
+#define MCT_L_INT_ENB_OFFSET		(0x34)
+#define MCT_L_WSTAT_OFFSET		(0x40)
+
+#define MCT_G_TCON_START		(1 << 8)
+#define MCT_G_TCON_COMP0_AUTO_INC	(1 << 1)
+#define MCT_G_TCON_COMP0_ENABLE		(1 << 0)
+
+#define MCT_L_TCON_INTERVAL_MODE	(1 << 2)
+#define MCT_L_TCON_INT_START		(1 << 1)
+#define MCT_L_TCON_TIMER_START		(1 << 0)
+
+#endif /* __ASM_ARCH_REGS_MCT_H */