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authorLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 09:38:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 09:38:16 -0700
commit99c6bcf46d2233d33e441834e958ed0bc22b190a (patch)
tree25abf5e856bc0f08d75e623715eb5acc4d4de2b2 /drivers/clocksource/timer-prima2.c
parent97b1007a2924aaa9126398623f6755a8c3c6a616 (diff)
parent2fdfe1c26fb9f24cfdf124384abb35396ca2cd3f (diff)
Merge tag 'multiplatform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC multiplatform updates from Olof Johansson: "More multiplatform enablement for ARM platforms. The ones converted in this branch are: - bcm2835 - cns3xxx - sirf - nomadik - msx - spear - tegra - ux500 We're getting close to having most of them converted! One of the larger platforms remaining is Samsung Exynos, and there are a bunch of supporting patches in this merge window for it. There was a patch in this branch to a early version of multiplatform conversion, but it ended up being reverted due to need of more bake time. The revert commit is part of the branch since it would have required rebasing multiple dependent branches and they were stable by then" * tag 'multiplatform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (70 commits) mmc: sdhci-s3c: Fix operation on non-single image Samsung platforms clocksource: nomadik-mtu: fix up clocksource/timer Revert "ARM: exynos: enable multiplatform support" ARM: SPEAr13xx: Fix typo "ARCH_HAVE_CPUFREQ" ARM: exynos: enable multiplatform support rtc: s3c: make header file local mtd: onenand/samsung: make regs-onenand.h file local thermal/exynos: remove unnecessary header inclusions mmc: sdhci-s3c: remove platform dependencies ARM: samsung: move mfc device definition to s5p-dev-mfc.c ARM: exynos: move debug-macro.S to include/debug/ ARM: exynos: prepare for sparse IRQ ARM: exynos: introduce EXYNOS_ATAGS symbol ARM: tegra: build assembly files with -march=armv7-a ARM: Push selects for TWD/SCU into machine entries ARM: ux500: build hotplug.o for ARMv7-a ARM: ux500: move to multiplatform ARM: ux500: make remaining headers local ARM: ux500: make irqs.h local to platform ARM: ux500: get rid of <mach/[hardware|db8500-regs].h> ...
Diffstat (limited to 'drivers/clocksource/timer-prima2.c')
-rw-r--r--drivers/clocksource/timer-prima2.c215
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-prima2.c b/drivers/clocksource/timer-prima2.c
new file mode 100644
index 00000000000..760882665d7
--- /dev/null
+++ b/drivers/clocksource/timer-prima2.c
@@ -0,0 +1,215 @@
+/*
+ * 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_irq.h>
+#include <linux/of_address.h>
+#include <asm/sched_clock.h>
+#include <asm/mach/time.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;
+
+/* 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)
+{
+ sirfsoc_clockevent.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&sirfsoc_clockevent, CLOCK_TICK_RATE,
+ 2, -2);
+}
+
+/* initialize the kernel jiffy timer source */
+static void __init sirfsoc_prima2_timer_init(struct device_node *np)
+{
+ unsigned long rate;
+ struct clk *clk;
+
+ /* 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_timer_base = of_iomap(np, 0);
+ if (!sirfsoc_timer_base)
+ panic("unable to map timer cpu registers\n");
+
+ sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
+
+ 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();
+}
+CLOCKSOURCE_OF_DECLARE(sirfsoc_prima2_timer, "sirf,prima2-tick", sirfsoc_prima2_timer_init);