+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * System timer for CSR SiRFprimaII
- *
- * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
- */
-
-#include <linux/kernel.h>
-#include <linux/interrupt.h>
-#include <linux/clockchips.h>
-#include <linux/clocksource.h>
-#include <linux/cpu.h>
-#include <linux/bitops.h>
-#include <linux/irq.h>
-#include <linux/clk.h>
-#include <linux/slab.h>
-#include <linux/of.h>
-#include <linux/of_irq.h>
-#include <linux/of_address.h>
-#include <linux/sched_clock.h>
-
-#define SIRFSOC_TIMER_32COUNTER_0_CTRL 0x0000
-#define SIRFSOC_TIMER_32COUNTER_1_CTRL 0x0004
-#define SIRFSOC_TIMER_MATCH_0 0x0018
-#define SIRFSOC_TIMER_MATCH_1 0x001c
-#define SIRFSOC_TIMER_COUNTER_0 0x0048
-#define SIRFSOC_TIMER_COUNTER_1 0x004c
-#define SIRFSOC_TIMER_INTR_STATUS 0x0060
-#define SIRFSOC_TIMER_WATCHDOG_EN 0x0064
-#define SIRFSOC_TIMER_64COUNTER_CTRL 0x0068
-#define SIRFSOC_TIMER_64COUNTER_LO 0x006c
-#define SIRFSOC_TIMER_64COUNTER_HI 0x0070
-#define SIRFSOC_TIMER_64COUNTER_LOAD_LO 0x0074
-#define SIRFSOC_TIMER_64COUNTER_LOAD_HI 0x0078
-#define SIRFSOC_TIMER_64COUNTER_RLATCHED_LO 0x007c
-#define SIRFSOC_TIMER_64COUNTER_RLATCHED_HI 0x0080
-
-#define SIRFSOC_TIMER_REG_CNT 6
-
-static unsigned long atlas7_timer_rate;
-
-static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
- SIRFSOC_TIMER_WATCHDOG_EN,
- SIRFSOC_TIMER_32COUNTER_0_CTRL,
- SIRFSOC_TIMER_32COUNTER_1_CTRL,
- SIRFSOC_TIMER_64COUNTER_CTRL,
- SIRFSOC_TIMER_64COUNTER_RLATCHED_LO,
- SIRFSOC_TIMER_64COUNTER_RLATCHED_HI,
-};
-
-static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];
-
-static void __iomem *sirfsoc_timer_base;
-
-/* disable count and interrupt */
-static inline void sirfsoc_timer_count_disable(int idx)
-{
- writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) & ~0x7,
- sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
-}
-
-/* enable count and interrupt */
-static inline void sirfsoc_timer_count_enable(int idx)
-{
- writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) | 0x3,
- sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
-}
-
-/* timer interrupt handler */
-static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
-{
- struct clock_event_device *ce = dev_id;
- int cpu = smp_processor_id();
-
- /* clear timer interrupt */
- writel_relaxed(BIT(cpu), sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);
-
- if (clockevent_state_oneshot(ce))
- sirfsoc_timer_count_disable(cpu);
-
- ce->event_handler(ce);
-
- return IRQ_HANDLED;
-}
-
-/* read 64-bit timer counter */
-static u64 sirfsoc_timer_read(struct clocksource *cs)
-{
- u64 cycles;
-
- writel_relaxed((readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
- BIT(0)) & ~BIT(1), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
-
- cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_HI);
- cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_LO);
-
- return cycles;
-}
-
-static int sirfsoc_timer_set_next_event(unsigned long delta,
- struct clock_event_device *ce)
-{
- int cpu = smp_processor_id();
-
- /* disable timer first, then modify the related registers */
- sirfsoc_timer_count_disable(cpu);
-
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0 +
- 4 * cpu);
- writel_relaxed(delta, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0 +
- 4 * cpu);
-
- /* enable the tick */
- sirfsoc_timer_count_enable(cpu);
-
- return 0;
-}
-
-/* Oneshot is enabled in set_next_event */
-static int sirfsoc_timer_shutdown(struct clock_event_device *evt)
-{
- sirfsoc_timer_count_disable(smp_processor_id());
- return 0;
-}
-
-static void sirfsoc_clocksource_suspend(struct clocksource *cs)
-{
- int i;
-
- for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
- sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
-}
-
-static void sirfsoc_clocksource_resume(struct clocksource *cs)
-{
- int i;
-
- for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
- writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
-
- writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],
- sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
- writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],
- sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
-
- writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
- BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
-}
-
-static struct clock_event_device __percpu *sirfsoc_clockevent;
-
-static struct clocksource sirfsoc_clocksource = {
- .name = "sirfsoc_clocksource",
- .rating = 200,
- .mask = CLOCKSOURCE_MASK(64),
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
- .read = sirfsoc_timer_read,
- .suspend = sirfsoc_clocksource_suspend,
- .resume = sirfsoc_clocksource_resume,
-};
-
-static unsigned int sirfsoc_timer_irq, sirfsoc_timer1_irq;
-
-static int sirfsoc_local_timer_starting_cpu(unsigned int cpu)
-{
- struct clock_event_device *ce = per_cpu_ptr(sirfsoc_clockevent, cpu);
- unsigned int irq;
- const char *name;
-
- if (cpu == 0) {
- irq = sirfsoc_timer_irq;
- name = "sirfsoc_timer0";
- } else {
- irq = sirfsoc_timer1_irq;
- name = "sirfsoc_timer1";
- }
-
- ce->irq = irq;
- ce->name = "local_timer";
- ce->features = CLOCK_EVT_FEAT_ONESHOT;
- ce->rating = 200;
- ce->set_state_shutdown = sirfsoc_timer_shutdown;
- ce->set_state_oneshot = sirfsoc_timer_shutdown;
- ce->tick_resume = sirfsoc_timer_shutdown;
- ce->set_next_event = sirfsoc_timer_set_next_event;
- clockevents_calc_mult_shift(ce, atlas7_timer_rate, 60);
- ce->max_delta_ns = clockevent_delta2ns(-2, ce);
- ce->max_delta_ticks = (unsigned long)-2;
- ce->min_delta_ns = clockevent_delta2ns(2, ce);
- ce->min_delta_ticks = 2;
- ce->cpumask = cpumask_of(cpu);
-
- BUG_ON(request_irq(ce->irq, sirfsoc_timer_interrupt,
- IRQF_TIMER | IRQF_NOBALANCING, name, ce));
- irq_force_affinity(ce->irq, cpumask_of(cpu));
-
- clockevents_register_device(ce);
- return 0;
-}
-
-static int sirfsoc_local_timer_dying_cpu(unsigned int cpu)
-{
- struct clock_event_device *ce = per_cpu_ptr(sirfsoc_clockevent, cpu);
-
- sirfsoc_timer_count_disable(1);
-
- if (cpu == 0)
- free_irq(sirfsoc_timer_irq, ce);
- else
- free_irq(sirfsoc_timer1_irq, ce);
- return 0;
-}
-
-static int __init sirfsoc_clockevent_init(void)
-{
- sirfsoc_clockevent = alloc_percpu(struct clock_event_device);
- BUG_ON(!sirfsoc_clockevent);
-
- /* Install and invoke hotplug callbacks */
- return cpuhp_setup_state(CPUHP_AP_MARCO_TIMER_STARTING,
- "clockevents/marco:starting",
- sirfsoc_local_timer_starting_cpu,
- sirfsoc_local_timer_dying_cpu);
-}
-
-/* initialize the kernel jiffy timer source */
-static int __init sirfsoc_atlas7_timer_init(struct device_node *np)
-{
- struct clk *clk;
-
- clk = of_clk_get(np, 0);
- BUG_ON(IS_ERR(clk));
-
- BUG_ON(clk_prepare_enable(clk));
-
- atlas7_timer_rate = clk_get_rate(clk);
-
- /* timer dividers: 0, not divided */
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL);
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_1_CTRL);
-
- /* Initialize timer counters to 0 */
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
- writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
- BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0);
- writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_1);
-
- /* Clear all interrupts */
- writel_relaxed(0xFFFF, sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);
-
- BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, atlas7_timer_rate));
-
- return sirfsoc_clockevent_init();
-}
-
-static int __init sirfsoc_of_timer_init(struct device_node *np)
-{
- sirfsoc_timer_base = of_iomap(np, 0);
- if (!sirfsoc_timer_base) {
- pr_err("unable to map timer cpu registers\n");
- return -ENXIO;
- }
-
- sirfsoc_timer_irq = irq_of_parse_and_map(np, 0);
- if (!sirfsoc_timer_irq) {
- pr_err("No irq passed for timer0 via DT\n");
- return -EINVAL;
- }
-
- sirfsoc_timer1_irq = irq_of_parse_and_map(np, 1);
- if (!sirfsoc_timer1_irq) {
- pr_err("No irq passed for timer1 via DT\n");
- return -EINVAL;
- }
-
- return sirfsoc_atlas7_timer_init(np);
-}
-TIMER_OF_DECLARE(sirfsoc_atlas7_timer, "sirf,atlas7-tick", sirfsoc_of_timer_init);
git.samba.org / sfrench / cifs-2.6.git / commitdiff