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-rw-r--r--arch/arm/Kconfig2
-rw-r--r--arch/arm/mach-footbridge/dc21285-timer.c84
-rw-r--r--arch/arm/mach-footbridge/isa-timer.c129
3 files changed, 152 insertions, 63 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5cff165b7eb0..6d9fbfe32a2d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -346,7 +346,7 @@ config ARCH_FOOTBRIDGE
bool "FootBridge"
select CPU_SA110
select FOOTBRIDGE
- select ARCH_USES_GETTIMEOFFSET
+ select GENERIC_CLOCKEVENTS
help
Support for systems based on the DC21285 companion chip
("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
diff --git a/arch/arm/mach-footbridge/dc21285-timer.c b/arch/arm/mach-footbridge/dc21285-timer.c
index bc5e83fb5819..a921fe92b858 100644
--- a/arch/arm/mach-footbridge/dc21285-timer.c
+++ b/arch/arm/mach-footbridge/dc21285-timer.c
@@ -4,10 +4,11 @@
* Copyright (C) 1998 Russell King.
* Copyright (C) 1998 Phil Blundell
*/
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
-#include <linux/spinlock.h>
#include <asm/irq.h>
@@ -16,32 +17,76 @@
#include "common.h"
-/*
- * Footbridge timer 1 support.
- */
-static unsigned long timer1_latch;
+static cycle_t cksrc_dc21285_read(struct clocksource *cs)
+{
+ return cs->mask - *CSR_TIMER2_VALUE;
+}
-static unsigned long timer1_gettimeoffset (void)
+static int cksrc_dc21285_enable(struct clocksource *cs)
{
- unsigned long value = timer1_latch - *CSR_TIMER1_VALUE;
+ *CSR_TIMER2_LOAD = cs->mask;
+ *CSR_TIMER2_CLR = 0;
+ *CSR_TIMER2_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_DIV16;
+ return 0;
+}
- return ((tick_nsec / 1000) * value) / timer1_latch;
+static int cksrc_dc21285_disable(struct clocksource *cs)
+{
+ *CSR_TIMER2_CNTL = 0;
}
-static irqreturn_t
-timer1_interrupt(int irq, void *dev_id)
+static struct clocksource cksrc_dc21285 = {
+ .name = "dc21285_timer2",
+ .rating = 200,
+ .read = cksrc_dc21285_read,
+ .enable = cksrc_dc21285_enable,
+ .disable = cksrc_dc21285_disable,
+ .mask = CLOCKSOURCE_MASK(24),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void ckevt_dc21285_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *c)
{
+ switch (mode) {
+ case CLOCK_EVT_MODE_RESUME:
+ case CLOCK_EVT_MODE_PERIODIC:
+ *CSR_TIMER1_CLR = 0;
+ *CSR_TIMER1_LOAD = (mem_fclk_21285 + 8 * HZ) / (16 * HZ);
+ *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD |
+ TIMER_CNTL_DIV16;
+ break;
+
+ default:
+ *CSR_TIMER1_CNTL = 0;
+ break;
+ }
+}
+
+static struct clock_event_device ckevt_dc21285 = {
+ .name = "dc21285_timer1",
+ .features = CLOCK_EVT_FEAT_PERIODIC,
+ .rating = 200,
+ .irq = IRQ_TIMER1,
+ .set_mode = ckevt_dc21285_set_mode,
+};
+
+static irqreturn_t timer1_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *ce = dev_id;
+
*CSR_TIMER1_CLR = 0;
- timer_tick();
+ ce->event_handler(ce);
return IRQ_HANDLED;
}
static struct irqaction footbridge_timer_irq = {
- .name = "Timer1 timer tick",
+ .name = "dc21285_timer1",
.handler = timer1_interrupt,
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &ckevt_dc21285,
};
/*
@@ -49,16 +94,19 @@ static struct irqaction footbridge_timer_irq = {
*/
static void __init footbridge_timer_init(void)
{
- timer1_latch = (mem_fclk_21285 + 8 * HZ) / (16 * HZ);
+ struct clock_event_device *ce = &ckevt_dc21285;
+
+ clocksource_register_hz(&cksrc_dc21285, (mem_fclk_21285 + 8) / 16);
+
+ setup_irq(ce->irq, &footbridge_timer_irq);
- *CSR_TIMER1_CLR = 0;
- *CSR_TIMER1_LOAD = timer1_latch;
- *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD | TIMER_CNTL_DIV16;
+ clockevents_calc_mult_shift(ce, mem_fclk_21285, 5);
+ ce->max_delta_ns = clockevent_delta2ns(0xffffff, ce);
+ ce->min_delta_ns = clockevent_delta2ns(0x000004, ce);
- setup_irq(IRQ_TIMER1, &footbridge_timer_irq);
+ clockevents_register_device(ce);
}
struct sys_timer footbridge_timer = {
.init = footbridge_timer_init,
- .offset = timer1_gettimeoffset,
};
diff --git a/arch/arm/mach-footbridge/isa-timer.c b/arch/arm/mach-footbridge/isa-timer.c
index f488fa2082d7..441c6ce0d555 100644
--- a/arch/arm/mach-footbridge/isa-timer.c
+++ b/arch/arm/mach-footbridge/isa-timer.c
@@ -4,10 +4,13 @@
* Copyright (C) 1998 Russell King.
* Copyright (C) 1998 Phil Blundell
*/
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
+#include <linux/timex.h>
#include <asm/irq.h>
@@ -15,77 +18,115 @@
#include "common.h"
-/*
- * ISA timer tick support
- */
-#define mSEC_10_from_14 ((14318180 + 100) / 200)
+#define PIT_MODE 0x43
+#define PIT_CH0 0x40
+
+#define PIT_LATCH ((PIT_TICK_RATE + HZ / 2) / HZ)
-static unsigned long isa_gettimeoffset(void)
+static cycle_t pit_read(struct clocksource *cs)
{
+ unsigned long flags;
+ static int old_count;
+ static u32 old_jifs;
int count;
+ u32 jifs;
- static int count_p = (mSEC_10_from_14/6); /* for the first call after boot */
- static unsigned long jiffies_p = 0;
+ raw_local_irq_save(flags);
- /*
- * cache volatile jiffies temporarily; we have IRQs turned off.
- */
- unsigned long jiffies_t;
+ jifs = jiffies;
+ outb_p(0x00, PIT_MODE); /* latch the count */
+ count = inb_p(PIT_CH0); /* read the latched count */
+ count |= inb_p(PIT_CH0) << 8;
- /* timer count may underflow right here */
- outb_p(0x00, 0x43); /* latch the count ASAP */
+ if (count > old_count && jifs == old_jifs)
+ count = old_count;
- count = inb_p(0x40); /* read the latched count */
+ old_count = count;
+ old_jifs = jifs;
- /*
- * We do this guaranteed double memory access instead of a _p
- * postfix in the previous port access. Wheee, hackady hack
- */
- jiffies_t = jiffies;
+ raw_local_irq_restore(flags);
- count |= inb_p(0x40) << 8;
+ count = (PIT_LATCH - 1) - count;
- /* Detect timer underflows. If we haven't had a timer tick since
- the last time we were called, and time is apparently going
- backwards, the counter must have wrapped during this routine. */
- if ((jiffies_t == jiffies_p) && (count > count_p))
- count -= (mSEC_10_from_14/6);
- else
- jiffies_p = jiffies_t;
+ return (cycle_t)(jifs * PIT_LATCH) + count;
+}
- count_p = count;
+static struct clocksource pit_cs = {
+ .name = "pit",
+ .rating = 110,
+ .read = pit_read,
+ .mask = CLOCKSOURCE_MASK(32),
+};
- count = (((mSEC_10_from_14/6)-1) - count) * (tick_nsec / 1000);
- count = (count + (mSEC_10_from_14/6)/2) / (mSEC_10_from_14/6);
+static void pit_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ unsigned long flags;
+
+ raw_local_irq_save(flags);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ outb_p(0x34, PIT_MODE);
+ outb_p(PIT_LATCH & 0xff, PIT_CH0);
+ outb_p(PIT_LATCH >> 8, PIT_CH0);
+ break;
+
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+ outb_p(0x30, PIT_MODE);
+ outb_p(0, PIT_CH0);
+ outb_p(0, PIT_CH0);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+ local_irq_restore(flags);
+}
- return count;
+static int pit_set_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ return 0;
}
-static irqreturn_t
-isa_timer_interrupt(int irq, void *dev_id)
+static struct clock_event_device pit_ce = {
+ .name = "pit",
+ .features = CLOCK_EVT_FEAT_PERIODIC,
+ .set_mode = pit_set_mode,
+ .set_next_event = pit_set_next_event,
+ .shift = 32,
+};
+
+static irqreturn_t pit_timer_interrupt(int irq, void *dev_id)
{
- timer_tick();
+ struct clock_event_device *ce = dev_id;
+ ce->event_handler(ce);
return IRQ_HANDLED;
}
-static struct irqaction isa_timer_irq = {
- .name = "ISA timer tick",
- .handler = isa_timer_interrupt,
+static struct irqaction pit_timer_irq = {
+ .name = "pit",
+ .handler = pit_timer_interrupt,
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &pit_ce,
};
static void __init isa_timer_init(void)
{
- /* enable PIT timer */
- /* set for periodic (4) and LSB/MSB write (0x30) */
- outb(0x34, 0x43);
- outb((mSEC_10_from_14/6) & 0xFF, 0x40);
- outb((mSEC_10_from_14/6) >> 8, 0x40);
+ pit_ce.cpumask = cpumask_of(smp_processor_id());
+ pit_ce.mult = div_sc(PIT_TICK_RATE, NSEC_PER_SEC, pit_ce.shift);
+ pit_ce.max_delta_ns = clockevent_delta2ns(0x7fff, &pit_ce);
+ pit_ce.min_delta_ns = clockevent_delta2ns(0x000f, &pit_ce);
+
+ clocksource_register_hz(&pit_cs, PIT_TICK_RATE);
- setup_irq(IRQ_ISA_TIMER, &isa_timer_irq);
+ setup_irq(pit_ce.irq, &pit_timer_irq);
+ clockevents_register_device(&pit_ce);
}
struct sys_timer isa_timer = {
.init = isa_timer_init,
- .offset = isa_gettimeoffset,
};
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-13 11:19:59 +0000