[ARM] 5477/1: Freescale STMP platform support [6/10]

Sources: common STMP3xxx platform support

Signed-off-by: dmitry pervushin <dpervushin@embeddedalley.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 172 insertions, 0 deletions

diff --git a/arch/arm/plat-stmp3xxx/timer.c b/arch/arm/plat-stmp3xxx/timer.c
new file mode 100644
index 0000000..c916068
--- /dev/null
+++ b/arch/arm/plat-stmp3xxx/timer.c
@@ -0,0 +1,172 @@
+/*
+ * 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/regs-timrot.h>
+
+static irqreturn_t
+stmp3xxx_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *c = dev_id;
+
+	if (HW_TIMROT_TIMCTRLn_RD(0) & (1<<15)) {
+		HW_TIMROT_TIMCTRLn_CLR(0, (1<<15));
+		c->event_handler(c);
+	} else if (HW_TIMROT_TIMCTRLn_RD(1) & (1<<15)) {
+		HW_TIMROT_TIMCTRLn_CLR(1, (1<<15));
+		HW_TIMROT_TIMCTRLn_CLR(1, BM_TIMROT_TIMCTRLn_IRQ_EN);
+		HW_TIMROT_TIMCOUNTn_WR(1, 0xFFFF);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static cycle_t stmp3xxx_clock_read(void)
+{
+	return ~((HW_TIMROT_TIMCOUNTn_RD(1) & 0xFFFF0000) >> 16);
+}
+
+static int
+stmp3xxx_timrot_set_next_event(unsigned long delta,
+		struct clock_event_device *dev)
+{
+	HW_TIMROT_TIMCOUNTn_WR(0, delta); /* reload */
+	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);
+
+	HW_TIMROT_ROTCTRL_CLR(BM_TIMROT_ROTCTRL_SFTRST |
+				BM_TIMROT_ROTCTRL_CLKGATE);
+	HW_TIMROT_TIMCOUNTn_WR(0, 0);
+	HW_TIMROT_TIMCOUNTn_WR(1, 0);
+
+	HW_TIMROT_TIMCTRLn_WR(0,
+			      (BF_TIMROT_TIMCTRLn_SELECT(8) |  /* 32 kHz */
+			       BF_TIMROT_TIMCTRLn_PRESCALE(0) |
+			       BM_TIMROT_TIMCTRLn_RELOAD |
+			       BM_TIMROT_TIMCTRLn_UPDATE |
+			       BM_TIMROT_TIMCTRLn_IRQ_EN));
+	HW_TIMROT_TIMCTRLn_WR(1,
+			      (BF_TIMROT_TIMCTRLn_SELECT(8) |  /* 32 kHz */
+			       BF_TIMROT_TIMCTRLn_PRESCALE(0) |
+			       BM_TIMROT_TIMCTRLn_RELOAD |
+			       BM_TIMROT_TIMCTRLn_UPDATE));
+
+	HW_TIMROT_TIMCOUNTn_WR(0, CLOCK_TICK_RATE / HZ - 1);
+	HW_TIMROT_TIMCOUNTn_WR(1, 0xFFFF); /* reload */
+
+	setup_irq(IRQ_TIMER0, &stmp3xxx_timer_irq);
+
+	clocksource_register(&cksrc_stmp3xxx);
+	clockevents_register_device(&ckevt_timrot);
+}
+
+#ifdef CONFIG_PM
+
+void stmp3xxx_suspend_timer(void)
+{
+	HW_TIMROT_TIMCTRLn_CLR(0, BM_TIMROT_TIMCTRLn_IRQ_EN);
+	HW_TIMROT_TIMCTRLn_CLR(0, (1<<15));
+	HW_TIMROT_ROTCTRL_SET(BM_TIMROT_ROTCTRL_CLKGATE);
+}
+
+void stmp3xxx_resume_timer(void)
+{
+	HW_TIMROT_ROTCTRL_CLR(BM_TIMROT_ROTCTRL_SFTRST |
+				BM_TIMROT_ROTCTRL_CLKGATE);
+
+
+	HW_TIMROT_TIMCTRLn_WR(0,
+			      (BF_TIMROT_TIMCTRLn_SELECT(8) |  /* 32 kHz */
+			       BF_TIMROT_TIMCTRLn_PRESCALE(0) |
+			       BM_TIMROT_TIMCTRLn_UPDATE |
+			       BM_TIMROT_TIMCTRLn_IRQ_EN));
+	HW_TIMROT_TIMCTRLn_WR(1,
+			      (BF_TIMROT_TIMCTRLn_SELECT(8) |  /* 32 kHz */
+			       BF_TIMROT_TIMCTRLn_PRESCALE(0) |
+			       BM_TIMROT_TIMCTRLn_RELOAD |
+			       BM_TIMROT_TIMCTRLn_UPDATE));
+
+	HW_TIMROT_TIMCOUNTn_WR(0, CLOCK_TICK_RATE / HZ - 1);
+	HW_TIMROT_TIMCOUNTn_WR(1, 0xFFFF); /* reload */
+}
+
+#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,
+};