Re: [PATCH] Add generic clock events support for w90p910 timer
From: Wan ZongShun
Date: Wed Aug 05 2009 - 02:46:49 EST
Dear sirs,
I fixed this patch according to Russell's advice, and added
time1 for clocksource.
Either setting 'LOCK_EVT_MODE_PERIODIC' or setting 'CLOCK_EVT_FEAT_ONESHOT' can
run in my w90p910 evaluation board. but, if I set 'future' to following:
".features = CLOCK_EVT_MODE_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,"
If so, the timer works on the periodic mode.
Signed-off-by: Wan ZongShun <mcuos.com@xxxxxxxxx>
---
arch/arm/Kconfig | 2 +
arch/arm/mach-w90x900/clock.c | 6 ++
arch/arm/mach-w90x900/time.c | 151 ++++++++++++++++++++++++++++++++------
arch/arm/mach-w90x900/w90p910.c | 2 +
4 files changed, 137 insertions(+), 24 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c3fed1e..8c4f03d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -495,6 +495,8 @@ config ARCH_W90X900
select GENERIC_GPIO
select HAVE_CLK
select COMMON_CLKDEV
+ select GENERIC_TIME
+ select GENERIC_CLOCKEVENTS
help
Support for Nuvoton (Winbond logic dept.) ARM9 processor,You
can login www.mcuos.com or www.nuvoton.com to know more.
diff --git a/arch/arm/mach-w90x900/clock.c b/arch/arm/mach-w90x900/clock.c
index 49cf1fb..70b6710 100644
--- a/arch/arm/mach-w90x900/clock.c
+++ b/arch/arm/mach-w90x900/clock.c
@@ -55,6 +55,12 @@ void clk_disable(struct clk *clk)
}
EXPORT_SYMBOL(clk_disable);
+unsigned long clk_get_rate(struct clk *clk)
+{
+ return 15000000;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
void w90x900_clk_enable(struct clk *clk, int enable)
{
unsigned int clocks = clk->cken;
diff --git a/arch/arm/mach-w90x900/time.c b/arch/arm/mach-w90x900/time.c
index bcc838f..5e06770 100644
--- a/arch/arm/mach-w90x900/time.c
+++ b/arch/arm/mach-w90x900/time.c
@@ -3,7 +3,7 @@
*
* Based on linux/arch/arm/plat-s3c24xx/time.c by Ben Dooks
*
- * Copyright (c) 2008 Nuvoton technology corporation
+ * Copyright (c) 2009 Nuvoton technology corporation
* All rights reserved.
*
* Wan ZongShun <mcuos.com@xxxxxxxxx>
@@ -23,6 +23,8 @@
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/leds.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <asm/mach-types.h>
#include <asm/mach/irq.h>
@@ -31,49 +33,150 @@
#include <mach/map.h>
#include <mach/regs-timer.h>
-static unsigned long w90x900_gettimeoffset(void)
+#define RESETINT 0x1f
+#define PERIOD (0x01 << 27)
+#define ONESHOT (0x00 << 27)
+#define COUNTEN (0x01 << 30)
+#define INTEN (0x01 << 29)
+
+#define TICKS_PER_SEC 100
+#define PRESCALE 0x63 /* Divider = prescale + 1 */
+
+unsigned int timer0_load;
+
+static void w90p910_clockevent_setmode(enum clock_event_mode mode,
+ struct clock_event_device *clk)
{
+ unsigned int val;
+
+ val = __raw_readl(REG_TCSR0);
+ val &= ~(0x03 << 27);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ __raw_writel(timer0_load, REG_TICR0);
+ val |= (PERIOD | COUNTEN | INTEN | PRESCALE);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ val |= (ONESHOT | COUNTEN | INTEN | PRESCALE);
+ break;
+
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+
+ __raw_writel(val, REG_TCSR0);
+}
+
+static int w90p910_clockevent_setnextevent(unsigned long evt,
+ struct clock_event_device *clk)
+{
+ unsigned int val;
+
+ __raw_writel(evt, REG_TICR0);
+
+ val = __raw_readl(REG_TCSR0);
+ val |= (COUNTEN | INTEN | PRESCALE);
+ __raw_writel(val, REG_TCSR0);
+
return 0;
}
+static struct clock_event_device w90p910_clockevent_device = {
+ .name = "w90p910-timer0",
+ .shift = 32,
+ .features = CLOCK_EVT_MODE_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = w90p910_clockevent_setmode,
+ .set_next_event = w90p910_clockevent_setnextevent,
+ .rating = 300,
+};
+
/*IRQ handler for the timer*/
-static irqreturn_t
-w90x900_timer_interrupt(int irq, void *dev_id)
+static irqreturn_t w90p910_timer0_interrupt(int irq, void *dev_id)
{
- timer_tick();
+ struct clock_event_device *evt = &w90p910_clockevent_device;
+
__raw_writel(0x01, REG_TISR); /* clear TIF0 */
+
+ evt->event_handler(evt);
return IRQ_HANDLED;
}
-static struct irqaction w90x900_timer_irq = {
- .name = "w90x900 Timer Tick",
+static struct irqaction w90p910_timer0_irq = {
+ .name = "w90p910-timer0",
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
- .handler = w90x900_timer_interrupt,
+ .handler = w90p910_timer0_interrupt,
};
-/*Set up timer reg.*/
+static void __init w90p910_clockevents_init(unsigned int rate)
+{
+ w90p910_clockevent_device.mult = div_sc(rate, NSEC_PER_SEC,
+ w90p910_clockevent_device.shift);
+ w90p910_clockevent_device.max_delta_ns = clockevent_delta2ns(0xffffffff,
+ &w90p910_clockevent_device);
+ w90p910_clockevent_device.min_delta_ns = clockevent_delta2ns(0xf,
+ &w90p910_clockevent_device);
+ w90p910_clockevent_device.cpumask = cpumask_of(0);
-static void w90x900_timer_setup(void)
+ clockevents_register_device(&w90p910_clockevent_device);
+}
+
+static cycle_t w90p910_get_cycles(struct clocksource *cs)
{
- __raw_writel(0, REG_TCSR0);
- __raw_writel(0, REG_TCSR1);
- __raw_writel(0, REG_TCSR2);
- __raw_writel(0, REG_TCSR3);
- __raw_writel(0, REG_TCSR4);
- __raw_writel(0x1F, REG_TISR);
- __raw_writel(15000000/(100 * 100), REG_TICR0);
- __raw_writel(0x68000063, REG_TCSR0);
+ return ~__raw_readl(REG_TDR1);
}
-static void __init w90x900_timer_init(void)
+static struct clocksource clocksource_w90p910 = {
+ .name = "w90p910-timer1",
+ .rating = 200,
+ .read = w90p910_get_cycles,
+ .mask = CLOCKSOURCE_MASK(32),
+ .shift = 20,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init w90p910_clocksource_init(unsigned int rate)
{
- w90x900_timer_setup();
- setup_irq(IRQ_TIMER0, &w90x900_timer_irq);
+ unsigned int val;
+
+ __raw_writel(0xffffffff, REG_TICR1);
+
+ val = __raw_readl(REG_TCSR1);
+ val |= (COUNTEN | PERIOD);
+ __raw_writel(val, REG_TCSR1);
+
+ clocksource_w90p910.mult =
+ clocksource_khz2mult((rate / 1000), clocksource_w90p910.shift);
+ clocksource_register(&clocksource_w90p910);
+}
+
+static void __init w90p910_timer_init(void)
+{
+ struct clk *ck_ext = clk_get(NULL, "ext");
+ unsigned int rate;
+
+ BUG_ON(IS_ERR(ck_ext));
+
+ rate = clk_get_rate(ck_ext);
+ clk_put(ck_ext);
+ rate = rate / (PRESCALE + 0x01);
+
+ /* set a known state */
+ __raw_writel(0x00, REG_TCSR0);
+ __raw_writel(0x00, REG_TCSR1);
+ __raw_writel(RESETINT, REG_TISR);
+ timer0_load = (rate / TICKS_PER_SEC);
+
+ setup_irq(IRQ_TIMER0, &w90p910_timer0_irq);
+
+ w90p910_clocksource_init(rate);
+ w90p910_clockevents_init(rate);
}
struct sys_timer w90x900_timer = {
- .init = w90x900_timer_init,
- .offset = w90x900_gettimeoffset,
- .resume = w90x900_timer_setup
+ .init = w90p910_timer_init,
};
diff --git a/arch/arm/mach-w90x900/w90p910.c b/arch/arm/mach-w90x900/w90p910.c
index 8444eab..d33723b 100644
--- a/arch/arm/mach-w90x900/w90p910.c
+++ b/arch/arm/mach-w90x900/w90p910.c
@@ -76,6 +76,7 @@ static DEFINE_CLK(wdt, 26);
static DEFINE_CLK(gdma, 27);
static DEFINE_CLK(adc, 28);
static DEFINE_CLK(usi, 29);
+static DEFINE_CLK(ext, 0);
static struct clk_lookup w90p910_clkregs[] = {
DEF_CLKLOOK(&clk_lcd, "w90p910-lcd", NULL),
@@ -97,6 +98,7 @@ static struct clk_lookup w90p910_clkregs[] = {
DEF_CLKLOOK(&clk_gdma, "w90p910-gdma", NULL),
DEF_CLKLOOK(&clk_adc, "w90p910-adc", NULL),
DEF_CLKLOOK(&clk_usi, "w90p910-spi", NULL),
+ DEF_CLKLOOK(&clk_ext, NULL, "ext"),
};
/* Initial serial platform data */
--
1.5.6.3
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/