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-rw-r--r--drivers/clocksource/Kconfig5
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/exynos_mct.c550
3 files changed, 556 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index e507ab7df60b..e8c453285151 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -67,3 +67,8 @@ config CLKSRC_METAG_GENERIC
def_bool y if METAG
help
This option enables support for the Meta per-thread timers.
+
+config CLKSRC_EXYNOS_MCT
+ def_bool y if ARCH_EXYNOS
+ help
+ Support for Multi Core Timer controller on Exynos SoCs.
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 4d8283aec5b5..1c1b15db7c4d 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
obj-$(CONFIG_SUNXI_TIMER) += sunxi_timer.o
obj-$(CONFIG_ARCH_TEGRA) += tegra20_timer.o
obj-$(CONFIG_VT8500_TIMER) += vt8500_timer.o
+obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o
obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o
diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
new file mode 100644
index 000000000000..545c98976e93
--- /dev/null
+++ b/drivers/clocksource/exynos_mct.c
@@ -0,0 +1,550 @@
+/* linux/arch/arm/mach-exynos4/mct.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * EXYNOS4 MCT(Multi-Core Timer) support
+ *
+ * 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/sched.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/percpu.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/clocksource.h>
+
+#include <asm/arch_timer.h>
+#include <asm/localtimer.h>
+
+#include <plat/cpu.h>
+
+#include <mach/map.h>
+#include <mach/irqs.h>
+#include <asm/mach/time.h>
+
+#define EXYNOS4_MCTREG(x) (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_L_BASE EXYNOS4_MCTREG(0x300)
+#define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * x))
+#define EXYNOS4_MCT_L_MASK (0xffffff00)
+
+#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)
+
+#define TICK_BASE_CNT 1
+
+enum {
+ MCT_INT_SPI,
+ MCT_INT_PPI
+};
+
+enum {
+ MCT_G0_IRQ,
+ MCT_G1_IRQ,
+ MCT_G2_IRQ,
+ MCT_G3_IRQ,
+ MCT_L0_IRQ,
+ MCT_L1_IRQ,
+ MCT_L2_IRQ,
+ MCT_L3_IRQ,
+ MCT_NR_IRQS,
+};
+
+static void __iomem *reg_base;
+static unsigned long clk_rate;
+static unsigned int mct_int_type;
+static int mct_irqs[MCT_NR_IRQS];
+
+struct mct_clock_event_device {
+ struct clock_event_device *evt;
+ unsigned long base;
+ char name[10];
+};
+
+static void exynos4_mct_write(unsigned int value, unsigned long offset)
+{
+ unsigned long stat_addr;
+ u32 mask;
+ u32 i;
+
+ __raw_writel(value, reg_base + offset);
+
+ if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) {
+ stat_addr = (offset & ~EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET;
+ switch (offset & EXYNOS4_MCT_L_MASK) {
+ case MCT_L_TCON_OFFSET:
+ mask = 1 << 3; /* L_TCON write status */
+ break;
+ case MCT_L_ICNTB_OFFSET:
+ mask = 1 << 1; /* L_ICNTB write status */
+ break;
+ case MCT_L_TCNTB_OFFSET:
+ mask = 1 << 0; /* L_TCNTB write status */
+ break;
+ default:
+ return;
+ }
+ } else {
+ switch (offset) {
+ case EXYNOS4_MCT_G_TCON:
+ stat_addr = EXYNOS4_MCT_G_WSTAT;
+ mask = 1 << 16; /* G_TCON write status */
+ break;
+ case EXYNOS4_MCT_G_COMP0_L:
+ stat_addr = EXYNOS4_MCT_G_WSTAT;
+ mask = 1 << 0; /* G_COMP0_L write status */
+ break;
+ case EXYNOS4_MCT_G_COMP0_U:
+ stat_addr = EXYNOS4_MCT_G_WSTAT;
+ mask = 1 << 1; /* G_COMP0_U write status */
+ break;
+ case EXYNOS4_MCT_G_COMP0_ADD_INCR:
+ stat_addr = EXYNOS4_MCT_G_WSTAT;
+ mask = 1 << 2; /* G_COMP0_ADD_INCR w status */
+ break;
+ case EXYNOS4_MCT_G_CNT_L:
+ stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
+ mask = 1 << 0; /* G_CNT_L write status */
+ break;
+ case EXYNOS4_MCT_G_CNT_U:
+ stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
+ mask = 1 << 1; /* G_CNT_U write status */
+ break;
+ default:
+ return;
+ }
+ }
+
+ /* Wait maximum 1 ms until written values are applied */
+ for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++)
+ if (__raw_readl(reg_base + stat_addr) & mask) {
+ __raw_writel(mask, reg_base + stat_addr);
+ return;
+ }
+
+ panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset);
+}
+
+/* Clocksource handling */
+static void exynos4_mct_frc_start(u32 hi, u32 lo)
+{
+ u32 reg;
+
+ exynos4_mct_write(lo, EXYNOS4_MCT_G_CNT_L);
+ exynos4_mct_write(hi, EXYNOS4_MCT_G_CNT_U);
+
+ reg = __raw_readl(reg_base + EXYNOS4_MCT_G_TCON);
+ reg |= MCT_G_TCON_START;
+ exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
+}
+
+static cycle_t exynos4_frc_read(struct clocksource *cs)
+{
+ unsigned int lo, hi;
+ u32 hi2 = __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_U);
+
+ do {
+ hi = hi2;
+ lo = __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_L);
+ hi2 = __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_U);
+ } while (hi != hi2);
+
+ return ((cycle_t)hi << 32) | lo;
+}
+
+static void exynos4_frc_resume(struct clocksource *cs)
+{
+ exynos4_mct_frc_start(0, 0);
+}
+
+struct clocksource mct_frc = {
+ .name = "mct-frc",
+ .rating = 400,
+ .read = exynos4_frc_read,
+ .mask = CLOCKSOURCE_MASK(64),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .resume = exynos4_frc_resume,
+};
+
+static void __init exynos4_clocksource_init(void)
+{
+ exynos4_mct_frc_start(0, 0);
+
+ if (clocksource_register_hz(&mct_frc, clk_rate))
+ panic("%s: can't register clocksource\n", mct_frc.name);
+}
+
+static void exynos4_mct_comp0_stop(void)
+{
+ unsigned int tcon;
+
+ tcon = __raw_readl(reg_base + EXYNOS4_MCT_G_TCON);
+ tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC);
+
+ exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON);
+ exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB);
+}
+
+static void exynos4_mct_comp0_start(enum clock_event_mode mode,
+ unsigned long cycles)
+{
+ unsigned int tcon;
+ cycle_t comp_cycle;
+
+ tcon = __raw_readl(reg_base + EXYNOS4_MCT_G_TCON);
+
+ if (mode == CLOCK_EVT_MODE_PERIODIC) {
+ tcon |= MCT_G_TCON_COMP0_AUTO_INC;
+ exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
+ }
+
+ comp_cycle = exynos4_frc_read(&mct_frc) + cycles;
+ exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L);
+ exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U);
+
+ exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB);
+
+ tcon |= MCT_G_TCON_COMP0_ENABLE;
+ exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON);
+}
+
+static int exynos4_comp_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ exynos4_mct_comp0_start(evt->mode, cycles);
+
+ return 0;
+}
+
+static void exynos4_comp_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ unsigned long cycles_per_jiffy;
+ exynos4_mct_comp0_stop();
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ cycles_per_jiffy =
+ (((unsigned long long) NSEC_PER_SEC / HZ * evt->mult) >> evt->shift);
+ exynos4_mct_comp0_start(mode, cycles_per_jiffy);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+}
+
+static struct clock_event_device mct_comp_device = {
+ .name = "mct-comp",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 250,
+ .set_next_event = exynos4_comp_set_next_event,
+ .set_mode = exynos4_comp_set_mode,
+};
+
+static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT);
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction mct_comp_event_irq = {
+ .name = "mct_comp_irq",
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = exynos4_mct_comp_isr,
+ .dev_id = &mct_comp_device,
+};
+
+static void exynos4_clockevent_init(void)
+{
+ mct_comp_device.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&mct_comp_device, clk_rate,
+ 0xf, 0xffffffff);
+ setup_irq(mct_irqs[MCT_G0_IRQ], &mct_comp_event_irq);
+}
+
+#ifdef CONFIG_LOCAL_TIMERS
+
+static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick);
+
+/* Clock event handling */
+static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt)
+{
+ unsigned long tmp;
+ unsigned long mask = MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START;
+ unsigned long offset = mevt->base + MCT_L_TCON_OFFSET;
+
+ tmp = __raw_readl(reg_base + offset);
+ if (tmp & mask) {
+ tmp &= ~mask;
+ exynos4_mct_write(tmp, offset);
+ }
+}
+
+static void exynos4_mct_tick_start(unsigned long cycles,
+ struct mct_clock_event_device *mevt)
+{
+ unsigned long tmp;
+
+ exynos4_mct_tick_stop(mevt);
+
+ tmp = (1 << 31) | cycles; /* MCT_L_UPDATE_ICNTB */
+
+ /* update interrupt count buffer */
+ exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET);
+
+ /* enable MCT tick interrupt */
+ exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET);
+
+ tmp = __raw_readl(reg_base + mevt->base + MCT_L_TCON_OFFSET);
+ tmp |= MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START |
+ MCT_L_TCON_INTERVAL_MODE;
+ exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET);
+}
+
+static int exynos4_tick_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
+
+ exynos4_mct_tick_start(cycles, mevt);
+
+ return 0;
+}
+
+static inline void exynos4_tick_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
+ unsigned long cycles_per_jiffy;
+
+ exynos4_mct_tick_stop(mevt);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ cycles_per_jiffy =
+ (((unsigned long long) NSEC_PER_SEC / HZ * evt->mult) >> evt->shift);
+ exynos4_mct_tick_start(cycles_per_jiffy, mevt);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+}
+
+static int exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
+{
+ struct clock_event_device *evt = mevt->evt;
+
+ /*
+ * This is for supporting oneshot mode.
+ * Mct would generate interrupt periodically
+ * without explicit stopping.
+ */
+ if (evt->mode != CLOCK_EVT_MODE_PERIODIC)
+ exynos4_mct_tick_stop(mevt);
+
+ /* Clear the MCT tick interrupt */
+ if (__raw_readl(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1) {
+ exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
+{
+ struct mct_clock_event_device *mevt = dev_id;
+ struct clock_event_device *evt = mevt->evt;
+
+ exynos4_mct_tick_clear(mevt);
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction mct_tick0_event_irq = {
+ .name = "mct_tick0_irq",
+ .flags = IRQF_TIMER | IRQF_NOBALANCING,
+ .handler = exynos4_mct_tick_isr,
+};
+
+static struct irqaction mct_tick1_event_irq = {
+ .name = "mct_tick1_irq",
+ .flags = IRQF_TIMER | IRQF_NOBALANCING,
+ .handler = exynos4_mct_tick_isr,
+};
+
+static int __cpuinit exynos4_local_timer_setup(struct clock_event_device *evt)
+{
+ struct mct_clock_event_device *mevt;
+ unsigned int cpu = smp_processor_id();
+
+ mevt = this_cpu_ptr(&percpu_mct_tick);
+ mevt->evt = evt;
+
+ mevt->base = EXYNOS4_MCT_L_BASE(cpu);
+ sprintf(mevt->name, "mct_tick%d", cpu);
+
+ evt->name = mevt->name;
+ evt->cpumask = cpumask_of(cpu);
+ evt->set_next_event = exynos4_tick_set_next_event;
+ evt->set_mode = exynos4_tick_set_mode;
+ evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+ evt->rating = 450;
+ clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
+ 0xf, 0x7fffffff);
+
+ exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
+
+ if (mct_int_type == MCT_INT_SPI) {
+ if (cpu == 0) {
+ mct_tick0_event_irq.dev_id = mevt;
+ evt->irq = mct_irqs[MCT_L0_IRQ];
+ setup_irq(evt->irq, &mct_tick0_event_irq);
+ } else {
+ mct_tick1_event_irq.dev_id = mevt;
+ evt->irq = mct_irqs[MCT_L1_IRQ];
+ setup_irq(evt->irq, &mct_tick1_event_irq);
+ irq_set_affinity(evt->irq, cpumask_of(1));
+ }
+ } else {
+ enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
+ }
+
+ return 0;
+}
+
+static void exynos4_local_timer_stop(struct clock_event_device *evt)
+{
+ unsigned int cpu = smp_processor_id();
+ evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
+ if (mct_int_type == MCT_INT_SPI)
+ if (cpu == 0)
+ remove_irq(evt->irq, &mct_tick0_event_irq);
+ else
+ remove_irq(evt->irq, &mct_tick1_event_irq);
+ else
+ disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
+}
+
+static struct local_timer_ops exynos4_mct_tick_ops __cpuinitdata = {
+ .setup = exynos4_local_timer_setup,
+ .stop = exynos4_local_timer_stop,
+};
+#endif /* CONFIG_LOCAL_TIMERS */
+
+static void __init exynos4_timer_resources(struct device_node *np)
+{
+ struct clk *mct_clk;
+ mct_clk = clk_get(NULL, "xtal");
+
+ clk_rate = clk_get_rate(mct_clk);
+
+ reg_base = np ? of_iomap(np, 0) : S5P_VA_SYSTIMER;
+ if (!reg_base)
+ panic("%s: unable to ioremap mct address space\n", __func__);
+
+#ifdef CONFIG_LOCAL_TIMERS
+ if (mct_int_type == MCT_INT_PPI) {
+ int err;
+
+ err = request_percpu_irq(mct_irqs[MCT_L0_IRQ],
+ exynos4_mct_tick_isr, "MCT",
+ &percpu_mct_tick);
+ WARN(err, "MCT: can't request IRQ %d (%d)\n",
+ mct_irqs[MCT_L0_IRQ], err);
+ }
+
+ local_timer_register(&exynos4_mct_tick_ops);
+#endif /* CONFIG_LOCAL_TIMERS */
+}
+
+static const struct of_device_id exynos_mct_ids[] = {
+ { .compatible = "samsung,exynos4210-mct", .data = (void *)MCT_INT_SPI },
+ { .compatible = "samsung,exynos4412-mct", .data = (void *)MCT_INT_PPI },
+};
+
+void __init mct_init(void)
+{
+ struct device_node *np = NULL;
+ const struct of_device_id *match;
+ u32 nr_irqs, i;
+
+#ifdef CONFIG_OF
+ np = of_find_matching_node_and_match(NULL, exynos_mct_ids, &match);
+#endif
+ if (np) {
+ mct_int_type = (u32)(match->data);
+
+ /* This driver uses only one global timer interrupt */
+ mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
+
+ /*
+ * Find out the number of local irqs specified. The local
+ * timer irqs are specified after the four global timer
+ * irqs are specified.
+ */
+#ifdef CONFIG_OF
+ nr_irqs = of_irq_count(np);
+#endif
+ for (i = MCT_L0_IRQ; i < nr_irqs; i++)
+ mct_irqs[i] = irq_of_parse_and_map(np, i);
+ } else if (soc_is_exynos4210()) {
+ mct_irqs[MCT_G0_IRQ] = EXYNOS4_IRQ_MCT_G0;
+ mct_irqs[MCT_L0_IRQ] = EXYNOS4_IRQ_MCT_L0;
+ mct_irqs[MCT_L1_IRQ] = EXYNOS4_IRQ_MCT_L1;
+ mct_int_type = MCT_INT_SPI;
+ } else {
+ panic("unable to determine mct controller type\n");
+ }
+
+ exynos4_timer_resources(np);
+ exynos4_clocksource_init();
+ exynos4_clockevent_init();
+}
+CLOCKSOURCE_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init)
+CLOCKSOURCE_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init)
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-29 04:17:12 +0300