[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 000000000000..c916068f0cab
--- /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,
+};