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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/clocksource/exynos_mct.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clocksource/exynos_mct.c')
-rw-r--r--drivers/clocksource/exynos_mct.c701
1 files changed, 701 insertions, 0 deletions
diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
new file mode 100644
index 000000000..bfd60093e
--- /dev/null
+++ b/drivers/clocksource/exynos_mct.c
@@ -0,0 +1,701 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* linux/arch/arm/mach-exynos4/mct.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * Exynos4 MCT(Multi-Core Timer) support
+*/
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.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 <linux/sched_clock.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
+
+#ifdef CONFIG_ARM
+/* Use values higher than ARM arch timer. See 6282edb72bed. */
+#define MCT_CLKSOURCE_RATING 450
+#define MCT_CLKEVENTS_RATING 500
+#else
+#define MCT_CLKSOURCE_RATING 350
+#define MCT_CLKEVENTS_RATING 350
+#endif
+
+/* There are four Global timers starting with 0 offset */
+#define MCT_G0_IRQ 0
+/* Local timers count starts after global timer count */
+#define MCT_L0_IRQ 4
+/* Max number of IRQ as per DT binding document */
+#define MCT_NR_IRQS 20
+/* Max number of local timers */
+#define MCT_NR_LOCAL (MCT_NR_IRQS - MCT_L0_IRQ)
+
+enum {
+ MCT_INT_SPI,
+ MCT_INT_PPI
+};
+
+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;
+ /**
+ * The length of the name must be adjusted if number of
+ * local timer interrupts grow over two digits
+ */
+ char name[11];
+};
+
+static void exynos4_mct_write(unsigned int value, unsigned long offset)
+{
+ unsigned long stat_addr;
+ u32 mask;
+ u32 i;
+
+ writel_relaxed(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 (readl_relaxed(reg_base + stat_addr) & mask) {
+ writel_relaxed(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(void)
+{
+ u32 reg;
+
+ reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
+ reg |= MCT_G_TCON_START;
+ exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
+}
+
+/**
+ * exynos4_read_count_64 - Read all 64-bits of the global counter
+ *
+ * This will read all 64-bits of the global counter taking care to make sure
+ * that the upper and lower half match. Note that reading the MCT can be quite
+ * slow (hundreds of nanoseconds) so you should use the 32-bit (lower half
+ * only) version when possible.
+ *
+ * Returns the number of cycles in the global counter.
+ */
+static u64 exynos4_read_count_64(void)
+{
+ unsigned int lo, hi;
+ u32 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
+
+ do {
+ hi = hi2;
+ lo = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
+ hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
+ } while (hi != hi2);
+
+ return ((u64)hi << 32) | lo;
+}
+
+/**
+ * exynos4_read_count_32 - Read the lower 32-bits of the global counter
+ *
+ * This will read just the lower 32-bits of the global counter. This is marked
+ * as notrace so it can be used by the scheduler clock.
+ *
+ * Returns the number of cycles in the global counter (lower 32 bits).
+ */
+static u32 notrace exynos4_read_count_32(void)
+{
+ return readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
+}
+
+static u64 exynos4_frc_read(struct clocksource *cs)
+{
+ return exynos4_read_count_32();
+}
+
+static void exynos4_frc_resume(struct clocksource *cs)
+{
+ exynos4_mct_frc_start();
+}
+
+static struct clocksource mct_frc = {
+ .name = "mct-frc",
+ .rating = MCT_CLKSOURCE_RATING,
+ .read = exynos4_frc_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .resume = exynos4_frc_resume,
+};
+
+static u64 notrace exynos4_read_sched_clock(void)
+{
+ return exynos4_read_count_32();
+}
+
+#if defined(CONFIG_ARM)
+static struct delay_timer exynos4_delay_timer;
+
+static cycles_t exynos4_read_current_timer(void)
+{
+ BUILD_BUG_ON_MSG(sizeof(cycles_t) != sizeof(u32),
+ "cycles_t needs to move to 32-bit for ARM64 usage");
+ return exynos4_read_count_32();
+}
+#endif
+
+static int __init exynos4_clocksource_init(bool frc_shared)
+{
+ /*
+ * When the frc is shared, the main processer should have already
+ * turned it on and we shouldn't be writing to TCON.
+ */
+ if (frc_shared)
+ mct_frc.resume = NULL;
+ else
+ exynos4_mct_frc_start();
+
+#if defined(CONFIG_ARM)
+ exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer;
+ exynos4_delay_timer.freq = clk_rate;
+ register_current_timer_delay(&exynos4_delay_timer);
+#endif
+
+ if (clocksource_register_hz(&mct_frc, clk_rate))
+ panic("%s: can't register clocksource\n", mct_frc.name);
+
+ sched_clock_register(exynos4_read_sched_clock, 32, clk_rate);
+
+ return 0;
+}
+
+static void exynos4_mct_comp0_stop(void)
+{
+ unsigned int tcon;
+
+ tcon = readl_relaxed(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(bool periodic, unsigned long cycles)
+{
+ unsigned int tcon;
+ u64 comp_cycle;
+
+ tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
+
+ if (periodic) {
+ tcon |= MCT_G_TCON_COMP0_AUTO_INC;
+ exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
+ }
+
+ comp_cycle = exynos4_read_count_64() + 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(false, cycles);
+
+ return 0;
+}
+
+static int mct_set_state_shutdown(struct clock_event_device *evt)
+{
+ exynos4_mct_comp0_stop();
+ return 0;
+}
+
+static int mct_set_state_periodic(struct clock_event_device *evt)
+{
+ unsigned long cycles_per_jiffy;
+
+ cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
+ >> evt->shift);
+ exynos4_mct_comp0_stop();
+ exynos4_mct_comp0_start(true, cycles_per_jiffy);
+ return 0;
+}
+
+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_state_periodic = mct_set_state_periodic,
+ .set_state_shutdown = mct_set_state_shutdown,
+ .set_state_oneshot = mct_set_state_shutdown,
+ .set_state_oneshot_stopped = mct_set_state_shutdown,
+ .tick_resume = mct_set_state_shutdown,
+};
+
+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 int exynos4_clockevent_init(void)
+{
+ mct_comp_device.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&mct_comp_device, clk_rate,
+ 0xf, 0xffffffff);
+ if (request_irq(mct_irqs[MCT_G0_IRQ], exynos4_mct_comp_isr,
+ IRQF_TIMER | IRQF_IRQPOLL, "mct_comp_irq",
+ &mct_comp_device))
+ pr_err("%s: request_irq() failed\n", "mct_comp_irq");
+
+ return 0;
+}
+
+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 = readl_relaxed(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 = readl_relaxed(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 void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
+{
+ /* Clear the MCT tick interrupt */
+ if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
+ exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
+}
+
+static int exynos4_tick_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ struct mct_clock_event_device *mevt;
+
+ mevt = container_of(evt, struct mct_clock_event_device, evt);
+ exynos4_mct_tick_start(cycles, mevt);
+ return 0;
+}
+
+static int set_state_shutdown(struct clock_event_device *evt)
+{
+ struct mct_clock_event_device *mevt;
+
+ mevt = container_of(evt, struct mct_clock_event_device, evt);
+ exynos4_mct_tick_stop(mevt);
+ exynos4_mct_tick_clear(mevt);
+ return 0;
+}
+
+static int set_state_periodic(struct clock_event_device *evt)
+{
+ struct mct_clock_event_device *mevt;
+ unsigned long cycles_per_jiffy;
+
+ mevt = container_of(evt, struct mct_clock_event_device, evt);
+ cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
+ >> evt->shift);
+ exynos4_mct_tick_stop(mevt);
+ exynos4_mct_tick_start(cycles_per_jiffy, mevt);
+ 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;
+
+ /*
+ * This is for supporting oneshot mode.
+ * Mct would generate interrupt periodically
+ * without explicit stopping.
+ */
+ if (!clockevent_state_periodic(&mevt->evt))
+ exynos4_mct_tick_stop(mevt);
+
+ exynos4_mct_tick_clear(mevt);
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static int exynos4_mct_starting_cpu(unsigned int cpu)
+{
+ struct mct_clock_event_device *mevt =
+ per_cpu_ptr(&percpu_mct_tick, cpu);
+ struct clock_event_device *evt = &mevt->evt;
+
+ snprintf(mevt->name, sizeof(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_state_periodic = set_state_periodic;
+ evt->set_state_shutdown = set_state_shutdown;
+ evt->set_state_oneshot = set_state_shutdown;
+ evt->set_state_oneshot_stopped = set_state_shutdown;
+ evt->tick_resume = set_state_shutdown;
+ evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_PERCPU;
+ evt->rating = MCT_CLKEVENTS_RATING;
+
+ exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
+
+ if (mct_int_type == MCT_INT_SPI) {
+
+ if (evt->irq == -1)
+ return -EIO;
+
+ irq_force_affinity(evt->irq, cpumask_of(cpu));
+ enable_irq(evt->irq);
+ } else {
+ enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
+ }
+ clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
+ 0xf, 0x7fffffff);
+
+ return 0;
+}
+
+static int exynos4_mct_dying_cpu(unsigned int cpu)
+{
+ struct mct_clock_event_device *mevt =
+ per_cpu_ptr(&percpu_mct_tick, cpu);
+ struct clock_event_device *evt = &mevt->evt;
+
+ evt->set_state_shutdown(evt);
+ if (mct_int_type == MCT_INT_SPI) {
+ if (evt->irq != -1)
+ disable_irq_nosync(evt->irq);
+ exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
+ } else {
+ disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
+ }
+ return 0;
+}
+
+static int __init exynos4_timer_resources(struct device_node *np)
+{
+ struct clk *mct_clk, *tick_clk;
+
+ reg_base = of_iomap(np, 0);
+ if (!reg_base)
+ panic("%s: unable to ioremap mct address space\n", __func__);
+
+ tick_clk = of_clk_get_by_name(np, "fin_pll");
+ if (IS_ERR(tick_clk))
+ panic("%s: unable to determine tick clock rate\n", __func__);
+ clk_rate = clk_get_rate(tick_clk);
+
+ mct_clk = of_clk_get_by_name(np, "mct");
+ if (IS_ERR(mct_clk))
+ panic("%s: unable to retrieve mct clock instance\n", __func__);
+ clk_prepare_enable(mct_clk);
+
+ return 0;
+}
+
+/**
+ * exynos4_timer_interrupts - initialize MCT interrupts
+ * @np: device node for MCT
+ * @int_type: interrupt type, MCT_INT_PPI or MCT_INT_SPI
+ * @local_idx: array mapping CPU numbers to local timer indices
+ * @nr_local: size of @local_idx array
+ */
+static int __init exynos4_timer_interrupts(struct device_node *np,
+ unsigned int int_type,
+ const u32 *local_idx,
+ size_t nr_local)
+{
+ int nr_irqs, i, err, cpu;
+
+ mct_int_type = int_type;
+
+ /* 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.
+ */
+ nr_irqs = of_irq_count(np);
+ if (nr_irqs > ARRAY_SIZE(mct_irqs)) {
+ pr_err("exynos-mct: too many (%d) interrupts configured in DT\n",
+ nr_irqs);
+ nr_irqs = ARRAY_SIZE(mct_irqs);
+ }
+ for (i = MCT_L0_IRQ; i < nr_irqs; i++)
+ mct_irqs[i] = irq_of_parse_and_map(np, i);
+
+ if (mct_int_type == MCT_INT_PPI) {
+
+ 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);
+ } else {
+ for_each_possible_cpu(cpu) {
+ int mct_irq;
+ unsigned int irq_idx;
+ struct mct_clock_event_device *pcpu_mevt =
+ per_cpu_ptr(&percpu_mct_tick, cpu);
+
+ if (cpu >= nr_local) {
+ err = -EINVAL;
+ goto out_irq;
+ }
+
+ irq_idx = MCT_L0_IRQ + local_idx[cpu];
+
+ pcpu_mevt->evt.irq = -1;
+ if (irq_idx >= ARRAY_SIZE(mct_irqs))
+ break;
+ mct_irq = mct_irqs[irq_idx];
+
+ irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);
+ if (request_irq(mct_irq,
+ exynos4_mct_tick_isr,
+ IRQF_TIMER | IRQF_NOBALANCING,
+ pcpu_mevt->name, pcpu_mevt)) {
+ pr_err("exynos-mct: cannot register IRQ (cpu%d)\n",
+ cpu);
+
+ continue;
+ }
+ pcpu_mevt->evt.irq = mct_irq;
+ }
+ }
+
+ for_each_possible_cpu(cpu) {
+ struct mct_clock_event_device *mevt = per_cpu_ptr(&percpu_mct_tick, cpu);
+
+ if (cpu >= nr_local) {
+ err = -EINVAL;
+ goto out_irq;
+ }
+
+ mevt->base = EXYNOS4_MCT_L_BASE(local_idx[cpu]);
+ }
+
+ /* Install hotplug callbacks which configure the timer on this CPU */
+ err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
+ "clockevents/exynos4/mct_timer:starting",
+ exynos4_mct_starting_cpu,
+ exynos4_mct_dying_cpu);
+ if (err)
+ goto out_irq;
+
+ return 0;
+
+out_irq:
+ if (mct_int_type == MCT_INT_PPI) {
+ free_percpu_irq(mct_irqs[MCT_L0_IRQ], &percpu_mct_tick);
+ } else {
+ for_each_possible_cpu(cpu) {
+ struct mct_clock_event_device *pcpu_mevt =
+ per_cpu_ptr(&percpu_mct_tick, cpu);
+
+ if (pcpu_mevt->evt.irq != -1) {
+ free_irq(pcpu_mevt->evt.irq, pcpu_mevt);
+ pcpu_mevt->evt.irq = -1;
+ }
+ }
+ }
+ return err;
+}
+
+static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
+{
+ bool frc_shared = of_property_read_bool(np, "samsung,frc-shared");
+ u32 local_idx[MCT_NR_LOCAL] = {0};
+ int nr_local;
+ int ret;
+
+ nr_local = of_property_count_u32_elems(np, "samsung,local-timers");
+ if (nr_local == 0)
+ return -EINVAL;
+ if (nr_local > 0) {
+ if (nr_local > ARRAY_SIZE(local_idx))
+ return -EINVAL;
+
+ ret = of_property_read_u32_array(np, "samsung,local-timers",
+ local_idx, nr_local);
+ if (ret)
+ return ret;
+ } else {
+ int i;
+
+ nr_local = ARRAY_SIZE(local_idx);
+ for (i = 0; i < nr_local; i++)
+ local_idx[i] = i;
+ }
+
+ ret = exynos4_timer_resources(np);
+ if (ret)
+ return ret;
+
+ ret = exynos4_timer_interrupts(np, int_type, local_idx, nr_local);
+ if (ret)
+ return ret;
+
+ ret = exynos4_clocksource_init(frc_shared);
+ if (ret)
+ return ret;
+
+ /*
+ * When the FRC is shared with a main processor, this secondary
+ * processor cannot use the global comparator.
+ */
+ if (frc_shared)
+ return ret;
+
+ return exynos4_clockevent_init();
+}
+
+
+static int __init mct_init_spi(struct device_node *np)
+{
+ return mct_init_dt(np, MCT_INT_SPI);
+}
+
+static int __init mct_init_ppi(struct device_node *np)
+{
+ return mct_init_dt(np, MCT_INT_PPI);
+}
+TIMER_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi);
+TIMER_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi);