[PATCH 2/3] Add hardware timer support for Mindspeed Comcerto platflorm

stanleymiao at gmail.com stanleymiao at gmail.com
Thu Oct 14 04:38:08 EDT 2010


From: Stanley.Miao <stanley.miao at windriver.com>

Add hardware timer support for Comcerto platflorm. Timer0 is used by MSP
and timer2 is used by fpp, so we choose timer1 for clockevent and timer3 for
clocksource.

Signed-off-by: Stanley.Miao <stanley.miao at windriver.com>
---
 arch/arm/mach-comcerto/Makefile                    |    2 +-
 .../arm/mach-comcerto/include/mach/comcerto-1000.h |    3 +
 .../include/mach/comcerto-1000/timer.h             |   62 ++++++
 arch/arm/mach-comcerto/include/mach/system.h       |    3 +
 arch/arm/mach-comcerto/time.c                      |  227 ++++++++++++++++++++
 5 files changed, 296 insertions(+), 1 deletions(-)
 create mode 100644 arch/arm/mach-comcerto/include/mach/comcerto-1000/timer.h
 create mode 100644 arch/arm/mach-comcerto/time.c

diff --git a/arch/arm/mach-comcerto/Makefile b/arch/arm/mach-comcerto/Makefile
index 70aac61..c514d20 100644
--- a/arch/arm/mach-comcerto/Makefile
+++ b/arch/arm/mach-comcerto/Makefile
@@ -4,7 +4,7 @@
 
 # Object file lists.
 
-obj-y :=
+obj-y := time.o
 
 obj-$(CONFIG_ARCH_M83XXX)			+= comcerto-1000.o
 obj-$(CONFIG_EVM_C1KMFCN_EVM)			+= board-c1kmfcn_evm.o
diff --git a/arch/arm/mach-comcerto/include/mach/comcerto-1000.h b/arch/arm/mach-comcerto/include/mach/comcerto-1000.h
index f48ae34..10086c4 100644
--- a/arch/arm/mach-comcerto/include/mach/comcerto-1000.h
+++ b/arch/arm/mach-comcerto/include/mach/comcerto-1000.h
@@ -88,4 +88,7 @@
 #define APB_VADDR_BASE			0xfc000000	/* VA of IO on APB bus */
 
 #define APB_VADDR(x)            ((x) - COMCERTO_AHB_APB_BASE + APB_VADDR_BASE)
+
+#include <mach/comcerto-1000/timer.h>
+
 #endif
diff --git a/arch/arm/mach-comcerto/include/mach/comcerto-1000/timer.h b/arch/arm/mach-comcerto/include/mach/comcerto-1000/timer.h
new file mode 100644
index 0000000..5372e37
--- /dev/null
+++ b/arch/arm/mach-comcerto/include/mach/comcerto-1000/timer.h
@@ -0,0 +1,62 @@
+/*
+ *  arch/arm/mach-comcerto/include/mach/comcerto-1000/timer.h
+ *
+ *  Copyright (C) 2004-2008 Mindspeed Technologies, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __TIMER_H__
+#define __TIMER_H__
+
+/* Comcerto Timers  */
+#define COMCERTO_TIMER0_HIGH_BOUND          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x00)
+#define COMCERTO_TIMER0_CURRENT_COUNT       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x04)
+#define COMCERTO_TIMER1_HIGH_BOUND          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x08)
+#define COMCERTO_TIMER1_CURRENT_COUNT       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x0C)
+#define COMCERTO_TIMER1_LOW_BOUND           APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x0C)
+#define COMCERTO_TIMER2_LOW_BOUND           APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x10)
+#define COMCERTO_TIMER2_HIGH_BOUND          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x14)
+#define COMCERTO_TIMER2_CTRL                APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x18)
+#define COMCERTO_TIMER2_CURRENT_COUNT       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x1C)
+#define COMCERTO_TIMER3_LOW_BOUND           APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x20)
+#define COMCERTO_TIMER3_HIGH_BOUND          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x24)
+#define COMCERTO_TIMER3_CTRL                APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x28)
+#define COMCERTO_TIMER3_CURRENT_COUNT       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x2C)
+#define COMCERTO_TIMER4_HIGH_BOUND          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x30)
+#define COMCERTO_TIMER4_CURRENT_COUNT       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x34)
+#define COMCERTO_TIMER5_LOW_BOUND           APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x38)
+#define COMCERTO_TIMER5_HIGH_BOUND          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x3C)
+#define COMCERTO_TIMER5_CURRENT_COUNT       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x40)
+#define COMCERTO_TIMER5_CTRL                APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x44)
+#define COMCERTO_TIMER_IRQ_MASK             APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x48)
+#define COMCERTO_TIMER_STATUS               APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x50)
+#define COMCERTO_TIMER_STATUS_CLR           APB_VADDR(COMCERTO_APB_TIMER_BASE + 0x50)
+#define COMCERTO_TIMER_WDT_HIGH_BOUND       APB_VADDR(COMCERTO_APB_TIMER_BASE + 0xD0)
+#define COMCERTO_TIMER_WDT_CONTROL          APB_VADDR(COMCERTO_APB_TIMER_BASE + 0xD4)
+#define COMCERTO_TIMER_WDT_CURRENT_COUNT    APB_VADDR(COMCERTO_APB_TIMER_BASE + 0xD8)
+
+#define COMCERTO_TIMER_WDT_CONTROL_TIMER_ENABLE		(1 << 0)
+
+/* COMCERTO_TIMER_IRQ_MASK */
+#define COMCERTO_TIMER0     0x01
+#define COMCERTO_TIMER1     0x02
+#define COMCERTO_TIMER2     0x04
+#define COMCERTO_TIMER3     0x08
+#define COMCERTO_TIMER4     0x10
+#define COMCERTO_TIMER5     0x20
+#define COMCERTO_ALL        0xFF
+#define COMCERTO_TIMER_CSP  (COMCERTO_TIMER1 | COMCERTO_TIMER2 | COMCERTO_TIMER3 | COMCERTO_TIMER4 | COMCERTO_TIMER5)
+#endif
diff --git a/arch/arm/mach-comcerto/include/mach/system.h b/arch/arm/mach-comcerto/include/mach/system.h
index 364cc7e..d24914d 100644
--- a/arch/arm/mach-comcerto/include/mach/system.h
+++ b/arch/arm/mach-comcerto/include/mach/system.h
@@ -34,6 +34,9 @@ static inline void arch_idle(void)
 
 static inline void arch_reset(char mode, const char *cmd)
 {
+	/* use watch dog timer to reset the board */
+	__raw_writel(0x1, COMCERTO_TIMER_WDT_CONTROL);
+	__raw_writel(0x1, COMCERTO_TIMER_WDT_HIGH_BOUND);
 }
 
 #endif /* __ASM_ARCH_SYSTEM_H */
diff --git a/arch/arm/mach-comcerto/time.c b/arch/arm/mach-comcerto/time.c
new file mode 100644
index 0000000..40e3515
--- /dev/null
+++ b/arch/arm/mach-comcerto/time.c
@@ -0,0 +1,227 @@
+/*
+ * linux/arch/arm/mach-comcerto/time.c
+ *
+ * Copyright (C) 2008 Mindspeed Technologies, Inc.
+ * Copyright (c) 2010 Wind River Systems, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+
+#include <mach/hardware.h>
+#include <asm/mach/time.h>
+
+#define TID_CLOCKEVENT	1
+#define TID_CLOCKSOURCE	3
+
+static DEFINE_SPINLOCK(timer_lock);
+
+struct comcerto_gptimer {
+	char *name;
+	unsigned long id; /* maybe not needed */
+	unsigned long mask;
+	unsigned long hbound;
+	unsigned long lbound;
+	unsigned long count;
+};
+
+static void gptimer_enable(struct comcerto_gptimer *gptimer)
+{
+	unsigned long flags;
+	unsigned long irq_mask;
+
+	spin_lock_irqsave(&timer_lock, flags);
+	irq_mask = __raw_readl(COMCERTO_TIMER_IRQ_MASK);
+	irq_mask |= gptimer->mask;
+	__raw_writel(irq_mask, COMCERTO_TIMER_IRQ_MASK);
+	spin_unlock_irqrestore(&timer_lock, flags);
+}
+
+static void gptimer_disable(struct comcerto_gptimer *gptimer)
+{
+	unsigned long flags;
+	unsigned long irq_mask;
+
+	spin_lock_irqsave(&timer_lock, flags);
+	irq_mask = __raw_readl(COMCERTO_TIMER_IRQ_MASK);
+	irq_mask &= ~gptimer->mask;
+	__raw_writel(irq_mask, COMCERTO_TIMER_IRQ_MASK);
+	spin_unlock_irqrestore(&timer_lock, flags);
+}
+
+static struct comcerto_gptimer timers[] = {
+	[TID_CLOCKEVENT] = {
+		.name	= "timer1",
+		.id	= TID_CLOCKEVENT,
+		.mask	= COMCERTO_TIMER1,
+		.hbound	= COMCERTO_TIMER1_HIGH_BOUND,
+		.lbound = COMCERTO_TIMER1_LOW_BOUND,
+		.count = COMCERTO_TIMER1_CURRENT_COUNT,
+	},
+	[TID_CLOCKSOURCE] = {
+		.name	= "timer3",
+		.id	= TID_CLOCKSOURCE,
+		.mask	= COMCERTO_TIMER3,
+		.hbound	= COMCERTO_TIMER3_HIGH_BOUND,
+		.lbound = COMCERTO_TIMER3_LOW_BOUND,
+		.count = COMCERTO_TIMER3_CURRENT_COUNT,
+	},
+};
+
+static void gptimer_set_bound(struct comcerto_gptimer *gptimer,
+					unsigned low, unsigned high)
+{
+	__raw_writel(high, gptimer->hbound);
+	/* __raw_writel(low, gptimer->lbound); */
+}
+
+static void gptimer_clear_status(struct comcerto_gptimer *gptimer)
+{
+	__raw_writel(gptimer->mask, COMCERTO_TIMER_STATUS_CLR);
+}
+
+static unsigned long gptimer_get_current_count(struct comcerto_gptimer *timer)
+{
+	return __raw_readl(timer->count);
+}
+
+static int comcerto_set_next_event(unsigned long cycles,
+					struct clock_event_device *evt)
+{
+	struct comcerto_gptimer *t = &timers[TID_CLOCKEVENT];
+
+	if (evt->mode == CLOCK_EVT_MODE_ONESHOT)
+		gptimer_enable(t);
+	return 0;
+}
+
+static void comcerto_set_mode(enum clock_event_mode mode,
+				struct clock_event_device *evt)
+{
+	struct comcerto_gptimer *t = &timers[TID_CLOCKEVENT];
+
+	if (mode != CLOCK_EVT_MODE_PERIODIC)
+		gptimer_disable(t);
+	else
+		gptimer_enable(t);
+}
+
+static struct clock_event_device clockevent = {
+	.name           = "clockevent",
+	.features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.rating         = 200,
+	.shift          = 24,
+	.set_mode       = comcerto_set_mode,
+	.set_next_event = comcerto_set_next_event,
+};
+
+static cycle_t comcerto_timer3_read(struct clocksource *cs)
+{
+	return (cycle_t)gptimer_get_current_count(&timers[TID_CLOCKSOURCE]);
+}
+
+static struct clocksource clocksource = {
+	.name   = "clocksource",
+	.rating = 200,
+	.read   = comcerto_timer3_read,
+	.mask   = CLOCKSOURCE_MASK(32),
+	.shift  = 24,
+	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init comcerto_clocksource_init(void)
+{
+	struct comcerto_gptimer *t = &timers[TID_CLOCKSOURCE];
+
+	gptimer_set_bound(t, 0, 0xffffffff);
+	clocksource.mult = clocksource_hz2mult(COMCERTO_DEFAULTAHBCLK, clocksource.shift);
+	if (clocksource_register(&clocksource))
+		printk(KERN_ERR "%s: can't register clocksource!\n", clocksource.name);
+}
+
+static irqreturn_t comcerto_timer1_interrupt(int irq, void *dev_id)
+{
+	u32 status;
+	struct comcerto_gptimer *t = &timers[TID_CLOCKEVENT];
+	struct clock_event_device *dev = &clockevent;
+
+	status = __raw_readl(COMCERTO_TIMER_STATUS) & __raw_readl(COMCERTO_TIMER_IRQ_MASK);
+
+	/* timer1 expired */
+	if (status & t->mask) {
+		/* we need to disable interrupt to simulate ONESHOT mode,
+		 * do it before clearing the interrupt to avoid race */
+		if (dev->mode != CLOCK_EVT_MODE_PERIODIC)
+			gptimer_disable(t);
+
+		gptimer_clear_status(t);
+		dev->event_handler(dev);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static struct irqaction comcerto_timer1_irq = {
+	.name           = "timer1",
+	.flags          = IRQF_DISABLED | IRQF_TIMER,
+	.handler        = comcerto_timer1_interrupt,
+};
+
+static void __init comcerto_clockevents_init(void)
+{
+	struct comcerto_gptimer *t = &timers[TID_CLOCKEVENT];
+
+	clockevent.mult = div_sc(COMCERTO_DEFAULTAHBCLK, NSEC_PER_SEC, clockevent.shift);
+	clockevent.max_delta_ns = clockevent_delta2ns(0x3fffffff, &clockevent);
+	clockevent.min_delta_ns = clockevent_delta2ns(1, &clockevent);
+	clockevent.cpumask = cpumask_of(0);
+	clockevents_register_device(&clockevent);
+
+	/* Clear all the timers except timer0  */
+	__raw_writel(COMCERTO_TIMER_CSP, COMCERTO_TIMER_STATUS);
+
+	/* Register interrupt handler for interrupt on IRQ_TIMERB*/
+	setup_irq(IRQ_TIMER1, &comcerto_timer1_irq);
+
+	/* Set and enable the system timer */
+	gptimer_set_bound(t, 0, COMCERTO_DEFAULTAHBCLK * 1000000 / HZ);
+}
+
+static void __init comcerto_timer_init(void)
+{
+	/*
+	 * DO NOT MODIFY THE CONFIGURATION OF TIMER0
+	 * It is used by the MSP
+	 * For C1000 FPP will be using TIMER2
+	 */
+
+	comcerto_clocksource_init();
+	comcerto_clockevents_init();
+}
+
+struct sys_timer comcerto_timer = {
+	.init           = comcerto_timer_init,
+};
-- 
1.5.4.3




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