--- /dev/null
- clockevents_calc_mult_shift(&sirfsoc_clockevent, CLOCK_TICK_RATE, 60);
-
- sirfsoc_clockevent.max_delta_ns =
- clockevent_delta2ns(-2, &sirfsoc_clockevent);
- sirfsoc_clockevent.min_delta_ns =
- clockevent_delta2ns(2, &sirfsoc_clockevent);
-
+ /*
+ * System timer for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+ #include <linux/kernel.h>
+ #include <linux/interrupt.h>
+ #include <linux/clockchips.h>
+ #include <linux/clocksource.h>
+ #include <linux/bitops.h>
+ #include <linux/irq.h>
+ #include <linux/clk.h>
+ #include <linux/err.h>
+ #include <linux/slab.h>
+ #include <linux/of.h>
+ #include <linux/of_address.h>
+ #include <mach/map.h>
+ #include <asm/sched_clock.h>
+ #include <asm/mach/time.h>
+
+ #include "common.h"
+
+ #define SIRFSOC_TIMER_COUNTER_LO 0x0000
+ #define SIRFSOC_TIMER_COUNTER_HI 0x0004
+ #define SIRFSOC_TIMER_MATCH_0 0x0008
+ #define SIRFSOC_TIMER_MATCH_1 0x000C
+ #define SIRFSOC_TIMER_MATCH_2 0x0010
+ #define SIRFSOC_TIMER_MATCH_3 0x0014
+ #define SIRFSOC_TIMER_MATCH_4 0x0018
+ #define SIRFSOC_TIMER_MATCH_5 0x001C
+ #define SIRFSOC_TIMER_STATUS 0x0020
+ #define SIRFSOC_TIMER_INT_EN 0x0024
+ #define SIRFSOC_TIMER_WATCHDOG_EN 0x0028
+ #define SIRFSOC_TIMER_DIV 0x002C
+ #define SIRFSOC_TIMER_LATCH 0x0030
+ #define SIRFSOC_TIMER_LATCHED_LO 0x0034
+ #define SIRFSOC_TIMER_LATCHED_HI 0x0038
+
+ #define SIRFSOC_TIMER_WDT_INDEX 5
+
+ #define SIRFSOC_TIMER_LATCH_BIT BIT(0)
+
+ #define SIRFSOC_TIMER_REG_CNT 11
+
+ static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
+ SIRFSOC_TIMER_MATCH_0, SIRFSOC_TIMER_MATCH_1, SIRFSOC_TIMER_MATCH_2,
+ SIRFSOC_TIMER_MATCH_3, SIRFSOC_TIMER_MATCH_4, SIRFSOC_TIMER_MATCH_5,
+ SIRFSOC_TIMER_INT_EN, SIRFSOC_TIMER_WATCHDOG_EN, SIRFSOC_TIMER_DIV,
+ SIRFSOC_TIMER_LATCHED_LO, SIRFSOC_TIMER_LATCHED_HI,
+ };
+
+ static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];
+
+ static void __iomem *sirfsoc_timer_base;
+ static void __init sirfsoc_of_timer_map(void);
+
+ /* timer0 interrupt handler */
+ static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
+ {
+ struct clock_event_device *ce = dev_id;
+
+ WARN_ON(!(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_STATUS) & BIT(0)));
+
+ /* clear timer0 interrupt */
+ writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
+
+ ce->event_handler(ce);
+
+ return IRQ_HANDLED;
+ }
+
+ /* read 64-bit timer counter */
+ static cycle_t sirfsoc_timer_read(struct clocksource *cs)
+ {
+ u64 cycles;
+
+ /* latch the 64-bit timer counter */
+ writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+ cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_HI);
+ cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+
+ return cycles;
+ }
+
+ static int sirfsoc_timer_set_next_event(unsigned long delta,
+ struct clock_event_device *ce)
+ {
+ unsigned long now, next;
+
+ writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+ now = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+ next = now + delta;
+ writel_relaxed(next, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0);
+ writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+ now = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+
+ return next - now > delta ? -ETIME : 0;
+ }
+
+ static void sirfsoc_timer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *ce)
+ {
+ u32 val = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ WARN_ON(1);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ writel_relaxed(val | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+ break;
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ writel_relaxed(val & ~BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+ break;
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+ }
+
+ static void sirfsoc_clocksource_suspend(struct clocksource *cs)
+ {
+ int i;
+
+ writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+
+ 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_COUNTER_LO);
+ writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1], sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
+ }
+
+ static struct clock_event_device sirfsoc_clockevent = {
+ .name = "sirfsoc_clockevent",
+ .rating = 200,
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = sirfsoc_timer_set_mode,
+ .set_next_event = sirfsoc_timer_set_next_event,
+ };
+
+ 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 struct irqaction sirfsoc_timer_irq = {
+ .name = "sirfsoc_timer0",
+ .flags = IRQF_TIMER,
+ .irq = 0,
+ .handler = sirfsoc_timer_interrupt,
+ .dev_id = &sirfsoc_clockevent,
+ };
+
+ /* Overwrite weak default sched_clock with more precise one */
+ static u32 notrace sirfsoc_read_sched_clock(void)
+ {
+ return (u32)(sirfsoc_timer_read(NULL) & 0xffffffff);
+ }
+
+ static void __init sirfsoc_clockevent_init(void)
+ {
- clockevents_register_device(&sirfsoc_clockevent);
+ sirfsoc_clockevent.cpumask = cpumask_of(0);
++ clockevents_config_and_register(&sirfsoc_clockevent, CLOCK_TICK_RATE,
++ 2, -2);
+ }
+
+ /* initialize the kernel jiffy timer source */
+ void __init sirfsoc_prima2_timer_init(void)
+ {
+ unsigned long rate;
+ struct clk *clk;
+
+ /* initialize clocking early, we want to set the OS timer */
+ sirfsoc_of_clk_init();
+
+ /* timer's input clock is io clock */
+ clk = clk_get_sys("io", NULL);
+
+ BUG_ON(IS_ERR(clk));
+
+ rate = clk_get_rate(clk);
+
+ BUG_ON(rate < CLOCK_TICK_RATE);
+ BUG_ON(rate % CLOCK_TICK_RATE);
+
+ sirfsoc_of_timer_map();
+
+ writel_relaxed(rate / CLOCK_TICK_RATE / 2 - 1, sirfsoc_timer_base + SIRFSOC_TIMER_DIV);
+ writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);
+ writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
+ writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
+
+ BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE));
+
+ setup_sched_clock(sirfsoc_read_sched_clock, 32, CLOCK_TICK_RATE);
+
+ BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));
+
+ sirfsoc_clockevent_init();
+ }
+
+ static struct of_device_id timer_ids[] = {
+ { .compatible = "sirf,prima2-tick" },
+ {},
+ };
+
+ static void __init sirfsoc_of_timer_map(void)
+ {
+ struct device_node *np;
+ const unsigned int *intspec;
+
+ np = of_find_matching_node(NULL, timer_ids);
+ if (!np)
+ return;
+ sirfsoc_timer_base = of_iomap(np, 0);
+ if (!sirfsoc_timer_base)
+ panic("unable to map timer cpu registers\n");
+
+ /* Get the interrupts property */
+ intspec = of_get_property(np, "interrupts", NULL);
+ BUG_ON(!intspec);
+ sirfsoc_timer_irq.irq = be32_to_cpup(intspec);
+
+ of_node_put(np);
+ }
projects / deliverable / linux.git / commitdiff
