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Diffstat (limited to 'arch/arm/plat-stmp3xxx/timer.c')
-rw-r--r--arch/arm/plat-stmp3xxx/timer.c189
1 files changed, 189 insertions, 0 deletions
diff --git a/arch/arm/plat-stmp3xxx/timer.c b/arch/arm/plat-stmp3xxx/timer.c
new file mode 100644
index 000000000000..063c7bc0e740
--- /dev/null
+++ b/arch/arm/plat-stmp3xxx/timer.c
@@ -0,0 +1,189 @@
+/*
+ * System timer for Freescale STMP37XX/STMP378X
+ *
+ * Embedded Alley Solutions, Inc <source@embeddedalley.com>
+ *
+ * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+
+#include <asm/mach/time.h>
+#include <mach/stmp3xxx.h>
+#include <mach/platform.h>
+#include <mach/regs-timrot.h>
+
+static irqreturn_t
+stmp3xxx_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *c = dev_id;
+
+ /* timer 0 */
+ if (__raw_readl(REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL0) &
+ BM_TIMROT_TIMCTRLn_IRQ) {
+ stmp3xxx_clearl(BM_TIMROT_TIMCTRLn_IRQ,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL0);
+ c->event_handler(c);
+ }
+
+ /* timer 1 */
+ else if (__raw_readl(REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL1)
+ & BM_TIMROT_TIMCTRLn_IRQ) {
+ stmp3xxx_clearl(BM_TIMROT_TIMCTRLn_IRQ,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL1);
+ stmp3xxx_clearl(BM_TIMROT_TIMCTRLn_IRQ_EN,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL1);
+ __raw_writel(0xFFFF, REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT1);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static cycle_t stmp3xxx_clock_read(struct clocksource *cs)
+{
+ return ~((__raw_readl(REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT1)
+ & 0xFFFF0000) >> 16);
+}
+
+static int
+stmp3xxx_timrot_set_next_event(unsigned long delta,
+ struct clock_event_device *dev)
+{
+ /* reload the timer */
+ __raw_writel(delta, REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT0);
+ return 0;
+}
+
+static void
+stmp3xxx_timrot_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *dev)
+{
+}
+
+static struct clock_event_device ckevt_timrot = {
+ .name = "timrot",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .shift = 32,
+ .set_next_event = stmp3xxx_timrot_set_next_event,
+ .set_mode = stmp3xxx_timrot_set_mode,
+};
+
+static struct clocksource cksrc_stmp3xxx = {
+ .name = "cksrc_stmp3xxx",
+ .rating = 250,
+ .read = stmp3xxx_clock_read,
+ .mask = CLOCKSOURCE_MASK(16),
+ .shift = 10,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static struct irqaction stmp3xxx_timer_irq = {
+ .name = "stmp3xxx_timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+ .handler = stmp3xxx_timer_interrupt,
+ .dev_id = &ckevt_timrot,
+};
+
+
+/*
+ * Set up timer interrupt, and return the current time in seconds.
+ */
+static void __init stmp3xxx_init_timer(void)
+{
+ cksrc_stmp3xxx.mult = clocksource_hz2mult(CLOCK_TICK_RATE,
+ cksrc_stmp3xxx.shift);
+ ckevt_timrot.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC,
+ ckevt_timrot.shift);
+ ckevt_timrot.min_delta_ns = clockevent_delta2ns(2, &ckevt_timrot);
+ ckevt_timrot.max_delta_ns = clockevent_delta2ns(0xFFF, &ckevt_timrot);
+ ckevt_timrot.cpumask = cpumask_of(0);
+
+ stmp3xxx_reset_block(REGS_TIMROT_BASE, false);
+
+ /* clear two timers */
+ __raw_writel(0, REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT0);
+ __raw_writel(0, REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT1);
+
+ /* configure them */
+ __raw_writel(
+ (8 << BP_TIMROT_TIMCTRLn_SELECT) | /* 32 kHz */
+ BM_TIMROT_TIMCTRLn_RELOAD |
+ BM_TIMROT_TIMCTRLn_UPDATE |
+ BM_TIMROT_TIMCTRLn_IRQ_EN,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL0);
+ __raw_writel(
+ (8 << BP_TIMROT_TIMCTRLn_SELECT) | /* 32 kHz */
+ BM_TIMROT_TIMCTRLn_RELOAD |
+ BM_TIMROT_TIMCTRLn_UPDATE |
+ BM_TIMROT_TIMCTRLn_IRQ_EN,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL1);
+
+ __raw_writel(CLOCK_TICK_RATE / HZ - 1,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT0);
+ __raw_writel(0xFFFF, REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT1);
+
+ setup_irq(IRQ_TIMER0, &stmp3xxx_timer_irq);
+
+ clocksource_register(&cksrc_stmp3xxx);
+ clockevents_register_device(&ckevt_timrot);
+}
+
+#ifdef CONFIG_PM
+
+void stmp3xxx_suspend_timer(void)
+{
+ stmp3xxx_clearl(BM_TIMROT_TIMCTRLn_IRQ_EN | BM_TIMROT_TIMCTRLn_IRQ,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL0);
+ stmp3xxx_setl(BM_TIMROT_ROTCTRL_CLKGATE,
+ REGS_TIMROT_BASE + HW_TIMROT_ROTCTRL);
+}
+
+void stmp3xxx_resume_timer(void)
+{
+ stmp3xxx_clearl(BM_TIMROT_ROTCTRL_SFTRST | BM_TIMROT_ROTCTRL_CLKGATE,
+ REGS_TIMROT_BASE + HW_TIMROT_ROTCTRL);
+ __raw_writel(
+ 8 << BP_TIMROT_TIMCTRLn_SELECT | /* 32 kHz */
+ BM_TIMROT_TIMCTRLn_RELOAD |
+ BM_TIMROT_TIMCTRLn_UPDATE |
+ BM_TIMROT_TIMCTRLn_IRQ_EN,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL0);
+ __raw_writel(
+ 8 << BP_TIMROT_TIMCTRLn_SELECT | /* 32 kHz */
+ BM_TIMROT_TIMCTRLn_RELOAD |
+ BM_TIMROT_TIMCTRLn_UPDATE |
+ BM_TIMROT_TIMCTRLn_IRQ_EN,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCTRL1);
+ __raw_writel(CLOCK_TICK_RATE / HZ - 1,
+ REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT0);
+ __raw_writel(0xFFFF, REGS_TIMROT_BASE + HW_TIMROT_TIMCOUNT1);
+}
+
+#else
+
+#define stmp3xxx_suspend_timer NULL
+#define stmp3xxx_resume_timer NULL
+
+#endif /* CONFIG_PM */
+
+struct sys_timer stmp3xxx_timer = {
+ .init = stmp3xxx_init_timer,
+ .suspend = stmp3xxx_suspend_timer,
+ .resume = stmp3xxx_resume_timer,
+};