[patch 0/5] i8253: common clockevent

[patch 0/5] i8253: common clockevent

[Thomas Gleixner]

Replace all the copies of i8253 clockevents code with a single common
implementation.

Thanks,

	tglx
---
 arch/arm/mach-footbridge/Kconfig     |    1 
 arch/arm/mach-footbridge/isa-timer.c |   51 -----------------
 arch/mips/Kconfig                    |    1 
 arch/mips/kernel/i8253.c             |   97 ---------------------------------
 arch/x86/Kconfig                     |    2 
 arch/x86/kernel/i8253.c              |   93 +-------------------------------
 drivers/clocksource/Kconfig          |    5 +
 drivers/clocksource/i8253.c          |  101 ++++++++++++++++++++++++++++++++---
 8 files changed, 107 insertions(+), 244 deletions(-)

[patch 1/5] i8253: Create common clockevent implementation

[Thomas Gleixner]

[-- Attachment #1: pit-clockevent-device.patch --]
[-- Type: text/plain, Size: 4567 bytes --]

arm, mips and x86 implement i8253 based clockevents. All the same code
copied. Create a common implementation in drivers/clocksource/i8253.c.

About time to rename drivers/clocksource/ to something else.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@arm.linux.org.uk>

---
 drivers/clocksource/Kconfig |    5 +-
 drivers/clocksource/i8253.c |  101 ++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 98 insertions(+), 8 deletions(-)

Index: linux-2.6-tip/drivers/clocksource/Kconfig
===================================================================
--- linux-2.6-tip.orig/drivers/clocksource/Kconfig
+++ linux-2.6-tip/drivers/clocksource/Kconfig
@@ -1,11 +1,14 @@
 config CLKSRC_I8253
 	bool
 
+config CLKEVT_I8253
+	bool
+
 config I8253_LOCK
 	bool
 
 config CLKBLD_I8253
-	def_bool y if CLKSRC_I8253 || I8253_LOCK
+	def_bool y if CLKSRC_I8253 || CLKEVT_I8253 || I8253_LOCK
 
 config CLKSRC_MMIO
 	bool
Index: linux-2.6-tip/drivers/clocksource/i8253.c
===================================================================
--- linux-2.6-tip.orig/drivers/clocksource/i8253.c
+++ linux-2.6-tip/drivers/clocksource/i8253.c
@@ -1,13 +1,14 @@
 /*
  * i8253 PIT clocksource
  */
-#include <linux/clocksource.h>
+#include <linux/clockchips.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
 #include <linux/module.h>
 #include <linux/i8253.h>
+#include <linux/smp.h>
 
 /*
  * Protects access to I/O ports
@@ -49,15 +50,15 @@ static cycle_t i8253_read(struct clockso
 	 * count), it cannot be newer.
 	 */
 	jifs = jiffies;
-	outb_pit(0x00, PIT_MODE);	/* latch the count ASAP */
-	count = inb_pit(PIT_CH0);	/* read the latched count */
-	count |= inb_pit(PIT_CH0) << 8;
+	outb_p(0x00, PIT_MODE);	/* latch the count ASAP */
+	count = inb_p(PIT_CH0);	/* read the latched count */
+	count |= inb_p(PIT_CH0) << 8;
 
 	/* VIA686a test code... reset the latch if count > max + 1 */
 	if (count > LATCH) {
-		outb_pit(0x34, PIT_MODE);
-		outb_pit(PIT_LATCH & 0xff, PIT_CH0);
-		outb_pit(PIT_LATCH >> 8, PIT_CH0);
+		outb_p(0x34, PIT_MODE);
+		outb_p(PIT_LATCH & 0xff, PIT_CH0);
+		outb_p(PIT_LATCH >> 8, PIT_CH0);
 		count = PIT_LATCH - 1;
 	}
 
@@ -99,3 +100,89 @@ int __init clocksource_i8253_init(void)
 	return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
 }
 #endif
+
+#ifdef CONFIG_CLKEVT_I8253
+/*
+ * Initialize the PIT timer.
+ *
+ * This is also called after resume to bring the PIT into operation again.
+ */
+static void init_pit_timer(enum clock_event_mode mode,
+			   struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		/* binary, mode 2, LSB/MSB, ch 0 */
+		outb_p(0x34, PIT_MODE);
+		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
+		outb_p(LATCH >> 8 , PIT_CH0);		/* MSB */
+		break;
+
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	case CLOCK_EVT_MODE_UNUSED:
+		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
+		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
+			outb_p(0x30, PIT_MODE);
+			outb_p(0, PIT_CH0);
+			outb_p(0, PIT_CH0);
+		}
+		break;
+
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* One shot setup */
+		outb_p(0x38, PIT_MODE);
+		break;
+
+	case CLOCK_EVT_MODE_RESUME:
+		/* Nothing to do here */
+		break;
+	}
+	raw_spin_unlock(&i8253_lock);
+}
+
+/*
+ * Program the next event in oneshot mode
+ *
+ * Delta is given in PIT ticks
+ */
+static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
+	outb_p(delta >> 8 , PIT_CH0);		/* MSB */
+	raw_spin_unlock(&i8253_lock);
+
+	return 0;
+}
+
+/*
+ * On UP the PIT can serve all of the possible timer functions. On SMP systems
+ * it can be solely used for the global tick.
+ */
+struct clock_event_device i8253_clockevent = {
+	.name		= "pit",
+	.features	= CLOCK_EVT_FEAT_PERIODIC,
+	.set_mode	= init_pit_timer,
+	.set_next_event = pit_next_event,
+};
+
+/*
+ * Initialize the conversion factor and the min/max deltas of the clock event
+ * structure and register the clock event source with the framework.
+ */
+void __init clockevent_i8253_init(bool oneshot)
+{
+	if (oneshot)
+		i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
+	/*
+	 * Start pit with the boot cpu mask. x86 might make it global
+	 * when it is used as broadcast device later.
+	 */
+	i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
+
+	clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
+					0xF, 0x7FFF);
+}
+#endif

[patch 2/5] x86: Use common i8253 clockevent

[Thomas Gleixner]

[-- Attachment #1: x86-use-common-i8253-ce.patch --]
[-- Type: text/plain, Size: 4022 bytes --]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/Kconfig        |    2 -
 arch/x86/kernel/i8253.c |   93 +-----------------------------------------------
 2 files changed, 4 insertions(+), 91 deletions(-)

Index: linux-2.6-tip/arch/x86/Kconfig
===================================================================
--- linux-2.6-tip.orig/arch/x86/Kconfig
+++ linux-2.6-tip/arch/x86/Kconfig
@@ -71,7 +71,7 @@ config X86
 	select IRQ_FORCED_THREADING
 	select USE_GENERIC_SMP_HELPERS if SMP
 	select HAVE_BPF_JIT if (X86_64 && NET)
-	select I8253_LOCK
+	select CLKEVT_I8253
 
 config INSTRUCTION_DECODER
 	def_bool (KPROBES || PERF_EVENTS)
Index: linux-2.6-tip/arch/x86/kernel/i8253.c
===================================================================
--- linux-2.6-tip.orig/arch/x86/kernel/i8253.c
+++ linux-2.6-tip/arch/x86/kernel/i8253.c
@@ -3,15 +3,9 @@
  *
  */
 #include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/spinlock.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/timex.h>
-#include <linux/delay.h>
 #include <linux/i8253.h>
-#include <linux/init.h>
-#include <linux/io.h>
 
 #include <asm/hpet.h>
 #include <asm/time.h>
@@ -23,91 +17,10 @@
  */
 struct clock_event_device *global_clock_event;
 
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_pit(0x34, PIT_MODE);
-		outb_pit(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb_pit(LATCH >> 8 , PIT_CH0);		/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_pit(0x30, PIT_MODE);
-			outb_pit(0, PIT_CH0);
-			outb_pit(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_pit(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_pit(delta & 0xff , PIT_CH0);	/* LSB */
-	outb_pit(delta >> 8 , PIT_CH0);		/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilities are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_ce = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	pit_ce.cpumask = cpumask_of(smp_processor_id());
-
-	clockevents_config_and_register(&pit_ce, CLOCK_TICK_RATE, 0xF, 0x7FFF);
-	global_clock_event = &pit_ce;
+	clockevent_i8253_init(true);
+	global_clock_event = &i8253_clockevent;
 }
 
 #ifndef CONFIG_X86_64
@@ -121,7 +34,7 @@ static int __init init_pit_clocksource(v
 	  * - when local APIC timer is active (PIT is switched off)
 	  */
 	if (num_possible_cpus() > 1 || is_hpet_enabled() ||
-	    pit_ce.mode != CLOCK_EVT_MODE_PERIODIC)
+	    i8253_clockevent.mode != CLOCK_EVT_MODE_PERIODIC)
 		return 0;
 
 	return clocksource_i8253_init();

[patch 3/5] mips: Use common i8253 clockevent

[Thomas Gleixner]

[-- Attachment #1: mips-use-common-i8253-ce.patch --]
[-- Type: text/plain, Size: 3913 bytes --]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
---
 arch/mips/Kconfig        |    1 
 arch/mips/kernel/i8253.c |   97 -----------------------------------------------
 2 files changed, 3 insertions(+), 95 deletions(-)

Index: linux-2.6-tip/arch/mips/Kconfig
===================================================================
--- linux-2.6-tip.orig/arch/mips/Kconfig
+++ linux-2.6-tip/arch/mips/Kconfig
@@ -2391,6 +2391,7 @@ config MMU
 config I8253
 	bool
 	select CLKSRC_I8253
+	select CLKEVT_I8253
 	select MIPS_EXTERNAL_TIMER
 
 config ZONE_DMA32
Index: linux-2.6-tip/arch/mips/kernel/i8253.c
===================================================================
--- linux-2.6-tip.orig/arch/mips/kernel/i8253.c
+++ linux-2.6-tip/arch/mips/kernel/i8253.c
@@ -4,92 +4,15 @@
  */
 #include <linux/clockchips.h>
 #include <linux/i8253.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/smp.h>
-#include <linux/spinlock.h>
 #include <linux/irq.h>
 
-#include <asm/delay.h>
-#include <asm/io.h>
 #include <asm/time.h>
 
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch(mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_p(0x34, PIT_MODE);
-		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb(LATCH >> 8 , PIT_CH0);	/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_p(0x30, PIT_MODE);
-			outb_p(0, PIT_CH0);
-			outb_p(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_p(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
-	outb(delta >> 8 , PIT_CH0);	/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilites are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_clockevent = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
-	pit_clockevent.event_handler(&pit_clockevent);
+	i8253_clockevent.event_handler(&pit_clockevent);
 
 	return IRQ_HANDLED;
 }
@@ -100,25 +23,9 @@ static struct irqaction irq0  = {
 	.name = "timer"
 };
 
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	struct clock_event_device *cd = &pit_clockevent;
-	unsigned int cpu = smp_processor_id();
-
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	cd->cpumask = cpumask_of(cpu);
-	clockevent_set_clock(cd, CLOCK_TICK_RATE);
-	cd->max_delta_ns = clockevent_delta2ns(0x7FFF, cd);
-	cd->min_delta_ns = clockevent_delta2ns(0xF, cd);
-	clockevents_register_device(cd);
-
+	clockevent_i8253_init(true);
 	setup_irq(0, &irq0);
 }
 

[patch 4/5] arm: footbridge: Use common i8253 clockevent

[Thomas Gleixner]

[-- Attachment #1: arm-use-common-i8253-ce.patch --]
[-- Type: text/plain, Size: 2786 bytes --]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
---
 arch/arm/mach-footbridge/Kconfig     |    1 
 arch/arm/mach-footbridge/isa-timer.c |   51 -----------------------------------
 2 files changed, 2 insertions(+), 50 deletions(-)

Index: linux-2.6-tip/arch/arm/mach-footbridge/Kconfig
===================================================================
--- linux-2.6-tip.orig/arch/arm/mach-footbridge/Kconfig
+++ linux-2.6-tip/arch/arm/mach-footbridge/Kconfig
@@ -5,6 +5,7 @@ menu "Footbridge Implementations"
 config ARCH_CATS
 	bool "CATS"
 	select CLKSRC_I8253
+	select CLKEVT_I8253
 	select FOOTBRIDGE_HOST
 	select ISA
 	select ISA_DMA
Index: linux-2.6-tip/arch/arm/mach-footbridge/isa-timer.c
===================================================================
--- linux-2.6-tip.orig/arch/arm/mach-footbridge/isa-timer.c
+++ linux-2.6-tip/arch/arm/mach-footbridge/isa-timer.c
@@ -5,12 +5,10 @@
  *  Copyright (C) 1998 Phil Blundell
  */
 #include <linux/clockchips.h>
-#include <linux/clocksource.h>
 #include <linux/i8253.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
-#include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
 
@@ -19,48 +17,6 @@
 
 #include "common.h"
 
-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);
-}
-
-static int pit_set_next_event(unsigned long delta,
-	struct clock_event_device *evt)
-{
-	return 0;
-}
-
-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)
 {
 	struct clock_event_device *ce = dev_id;
@@ -77,15 +33,10 @@ static struct irqaction pit_timer_irq = 
 
 static void __init isa_timer_init(void)
 {
-	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_i8253_init();
 
 	setup_irq(pit_ce.irq, &pit_timer_irq);
-	clockevents_register_device(&pit_ce);
+	clockevents_i8253_init(false);
 }
 
 struct sys_timer isa_timer = {

[patch 5/5] i8253: Cleanup outb/inb magic

[Thomas Gleixner]

[-- Attachment #1: i8253-cleanup-outb-inb-magic.patch --]
[-- Type: text/plain, Size: 1485 bytes --]

Remove the hysterical outb/inb_pit defines and use outb_p/inb_p in the
code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@arm.linux.org.uk>
---
 arch/x86/kernel/apm_32.c |    6 +++---
 include/linux/i8253.h    |    3 ---
 2 files changed, 3 insertions(+), 6 deletions(-)

Index: linux-2.6-tip/arch/x86/kernel/apm_32.c
===================================================================
--- linux-2.6-tip.orig/arch/x86/kernel/apm_32.c
+++ linux-2.6-tip/arch/x86/kernel/apm_32.c
@@ -1220,11 +1220,11 @@ static void reinit_timer(void)
 
 	raw_spin_lock_irqsave(&i8253_lock, flags);
 	/* set the clock to HZ */
-	outb_pit(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
+	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
 	udelay(10);
-	outb_pit(LATCH & 0xff, PIT_CH0);	/* LSB */
+	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
 	udelay(10);
-	outb_pit(LATCH >> 8, PIT_CH0);	/* MSB */
+	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
 	udelay(10);
 	raw_spin_unlock_irqrestore(&i8253_lock, flags);
 #endif
Index: linux-2.6-tip/include/linux/i8253.h
===================================================================
--- linux-2.6-tip.orig/include/linux/i8253.h
+++ linux-2.6-tip/include/linux/i8253.h
@@ -20,9 +20,6 @@
 
 #define PIT_LATCH	((PIT_TICK_RATE + HZ/2) / HZ)
 
-#define inb_pit         inb_p
-#define outb_pit        outb_p
-
 extern raw_spinlock_t i8253_lock;
 
 extern void setup_pit_timer(void);

Re: [patch 5/5] i8253: Cleanup outb/inb magic

[Ralf Baechle]

On Thu, Jun 09, 2011 at 01:08:30PM -0000, Thomas Gleixner wrote:

> Remove the hysterical outb/inb_pit defines and use outb_p/inb_p in the
> code.

FWIW, I've traced the use of inb_p and outb_p to access the PIT timer
all the way back to Linux 0.10

I wonder if any of the systems affected actually has enough memory to boot
a modern kernel or if the _p versions have become useless bagagge that
should be dropped - cleanup which would then also allow more code to the
iomap() API.

I'm interested because quite a few MIPS systems have been built based on
Intel, OPTi and other chipsets which may or may not have been affected.

  Ralf

Re: [patch 5/5] i8253: Cleanup outb/inb magic

[H. Peter Anvin]

On 06/09/2011 06:34 AM, Ralf Baechle wrote:
> On Thu, Jun 09, 2011 at 01:08:30PM -0000, Thomas Gleixner wrote:
> 
>> Remove the hysterical outb/inb_pit defines and use outb_p/inb_p in the
>> code.
> 
> FWIW, I've traced the use of inb_p and outb_p to access the PIT timer
> all the way back to Linux 0.10
> 
> I wonder if any of the systems affected actually has enough memory to boot
> a modern kernel or if the _p versions have become useless bagagge that
> should be dropped - cleanup which would then also allow more code to the
> iomap() API.
> 
> I'm interested because quite a few MIPS systems have been built based on
> Intel, OPTi and other chipsets which may or may not have been affected.
> 

On the x86 side, we already have configurability of the delay in
inb_p/outb_p... one option could be null delay.

	-hpa

[tip:timers/cleanup] i8253: Create common clockevent implementation

[tip-bot for Thomas Gleixner]

Commit-ID:  9f9119424bbc4e1c4c8690ea418fa6129dc9fa04
Gitweb:     http://git.kernel.org/tip/9f9119424bbc4e1c4c8690ea418fa6129dc9fa04
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:25 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 24 Jun 2011 16:22:54 +0200

i8253: Create common clockevent implementation

arm, mips and x86 implement i8253 based clockevents. All the same code
copied. Create a common implementation in drivers/clocksource/i8253.c.

About time to rename drivers/clocksource/ to something else.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130621.921710458@linutronix.de

---
 drivers/clocksource/Kconfig |    5 ++-
 drivers/clocksource/i8253.c |  101 ++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 98 insertions(+), 8 deletions(-)

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 330343b..d8d3e02 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -1,11 +1,14 @@
 config CLKSRC_I8253
 	bool
 
+config CLKEVT_I8253
+	bool
+
 config I8253_LOCK
 	bool
 
 config CLKBLD_I8253
-	def_bool y if CLKSRC_I8253 || I8253_LOCK
+	def_bool y if CLKSRC_I8253 || CLKEVT_I8253 || I8253_LOCK
 
 config CLKSRC_MMIO
 	bool
diff --git a/drivers/clocksource/i8253.c b/drivers/clocksource/i8253.c
index e594f52..27c49e6 100644
--- a/drivers/clocksource/i8253.c
+++ b/drivers/clocksource/i8253.c
@@ -1,13 +1,14 @@
 /*
  * i8253 PIT clocksource
  */
-#include <linux/clocksource.h>
+#include <linux/clockchips.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
 #include <linux/module.h>
 #include <linux/i8253.h>
+#include <linux/smp.h>
 
 /*
  * Protects access to I/O ports
@@ -47,15 +48,15 @@ static cycle_t i8253_read(struct clocksource *cs)
 	 * count), it cannot be newer.
 	 */
 	jifs = jiffies;
-	outb_pit(0x00, PIT_MODE);	/* latch the count ASAP */
-	count = inb_pit(PIT_CH0);	/* read the latched count */
-	count |= inb_pit(PIT_CH0) << 8;
+	outb_p(0x00, PIT_MODE);	/* latch the count ASAP */
+	count = inb_p(PIT_CH0);	/* read the latched count */
+	count |= inb_p(PIT_CH0) << 8;
 
 	/* VIA686a test code... reset the latch if count > max + 1 */
 	if (count > LATCH) {
-		outb_pit(0x34, PIT_MODE);
-		outb_pit(PIT_LATCH & 0xff, PIT_CH0);
-		outb_pit(PIT_LATCH >> 8, PIT_CH0);
+		outb_p(0x34, PIT_MODE);
+		outb_p(PIT_LATCH & 0xff, PIT_CH0);
+		outb_p(PIT_LATCH >> 8, PIT_CH0);
 		count = PIT_LATCH - 1;
 	}
 
@@ -97,3 +98,89 @@ int __init clocksource_i8253_init(void)
 	return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
 }
 #endif
+
+#ifdef CONFIG_CLKEVT_I8253
+/*
+ * Initialize the PIT timer.
+ *
+ * This is also called after resume to bring the PIT into operation again.
+ */
+static void init_pit_timer(enum clock_event_mode mode,
+			   struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		/* binary, mode 2, LSB/MSB, ch 0 */
+		outb_p(0x34, PIT_MODE);
+		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
+		outb_p(LATCH >> 8 , PIT_CH0);		/* MSB */
+		break;
+
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	case CLOCK_EVT_MODE_UNUSED:
+		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
+		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
+			outb_p(0x30, PIT_MODE);
+			outb_p(0, PIT_CH0);
+			outb_p(0, PIT_CH0);
+		}
+		break;
+
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* One shot setup */
+		outb_p(0x38, PIT_MODE);
+		break;
+
+	case CLOCK_EVT_MODE_RESUME:
+		/* Nothing to do here */
+		break;
+	}
+	raw_spin_unlock(&i8253_lock);
+}
+
+/*
+ * Program the next event in oneshot mode
+ *
+ * Delta is given in PIT ticks
+ */
+static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
+	outb_p(delta >> 8 , PIT_CH0);		/* MSB */
+	raw_spin_unlock(&i8253_lock);
+
+	return 0;
+}
+
+/*
+ * On UP the PIT can serve all of the possible timer functions. On SMP systems
+ * it can be solely used for the global tick.
+ */
+struct clock_event_device i8253_clockevent = {
+	.name		= "pit",
+	.features	= CLOCK_EVT_FEAT_PERIODIC,
+	.set_mode	= init_pit_timer,
+	.set_next_event = pit_next_event,
+};
+
+/*
+ * Initialize the conversion factor and the min/max deltas of the clock event
+ * structure and register the clock event source with the framework.
+ */
+void __init clockevent_i8253_init(bool oneshot)
+{
+	if (oneshot)
+		i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
+	/*
+	 * Start pit with the boot cpu mask. x86 might make it global
+	 * when it is used as broadcast device later.
+	 */
+	i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
+
+	clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
+					0xF, 0x7FFF);
+}
+#endif

[tip:timers/cleanup] x86: Use common i8253 clockevent

[tip-bot for Thomas Gleixner]

Commit-ID:  2739ce151665a72acdc19ed9dc6b9f6a235b7c30
Gitweb:     http://git.kernel.org/tip/2739ce151665a72acdc19ed9dc6b9f6a235b7c30
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:26 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 24 Jun 2011 16:22:54 +0200

x86: Use common i8253 clockevent

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.026152527@linutronix.de
---
 arch/x86/Kconfig        |    2 +-
 arch/x86/kernel/i8253.c |   93 ++---------------------------------------------
 2 files changed, 4 insertions(+), 91 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2dd95b5..26a14b4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -71,7 +71,7 @@ config X86
 	select IRQ_FORCED_THREADING
 	select USE_GENERIC_SMP_HELPERS if SMP
 	select HAVE_BPF_JIT if (X86_64 && NET)
-	select I8253_LOCK
+	select CLKEVT_I8253
 
 config INSTRUCTION_DECODER
 	def_bool (KPROBES || PERF_EVENTS)
diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c
index 5783e6d..f2b96de 100644
--- a/arch/x86/kernel/i8253.c
+++ b/arch/x86/kernel/i8253.c
@@ -3,15 +3,9 @@
  *
  */
 #include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/spinlock.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/timex.h>
-#include <linux/delay.h>
 #include <linux/i8253.h>
-#include <linux/init.h>
-#include <linux/io.h>
 
 #include <asm/hpet.h>
 #include <asm/time.h>
@@ -23,91 +17,10 @@
  */
 struct clock_event_device *global_clock_event;
 
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_pit(0x34, PIT_MODE);
-		outb_pit(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb_pit(LATCH >> 8 , PIT_CH0);		/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_pit(0x30, PIT_MODE);
-			outb_pit(0, PIT_CH0);
-			outb_pit(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_pit(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_pit(delta & 0xff , PIT_CH0);	/* LSB */
-	outb_pit(delta >> 8 , PIT_CH0);		/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilities are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_ce = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	pit_ce.cpumask = cpumask_of(smp_processor_id());
-
-	clockevents_config_and_register(&pit_ce, CLOCK_TICK_RATE, 0xF, 0x7FFF);
-	global_clock_event = &pit_ce;
+	clockevent_i8253_init(true);
+	global_clock_event = &i8253_clockevent;
 }
 
 #ifndef CONFIG_X86_64
@@ -121,7 +34,7 @@ static int __init init_pit_clocksource(void)
 	  * - when local APIC timer is active (PIT is switched off)
 	  */
 	if (num_possible_cpus() > 1 || is_hpet_enabled() ||
-	    pit_ce.mode != CLOCK_EVT_MODE_PERIODIC)
+	    i8253_clockevent.mode != CLOCK_EVT_MODE_PERIODIC)
 		return 0;
 
 	return clocksource_i8253_init();

[tip:timers/cleanup] mips: Use common i8253 clockevent

[tip-bot for Thomas Gleixner]

Commit-ID:  594fa4ac22954c9cb8d65040c5c3676778b08e1d
Gitweb:     http://git.kernel.org/tip/594fa4ac22954c9cb8d65040c5c3676778b08e1d
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:27 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 24 Jun 2011 16:22:55 +0200

mips: Use common i8253 clockevent

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.133068765@linutronix.de
---
 arch/mips/Kconfig        |    1 +
 arch/mips/kernel/i8253.c |   97 +---------------------------------------------
 2 files changed, 3 insertions(+), 95 deletions(-)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 45f7aac..6cb60ad 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2391,6 +2391,7 @@ config MMU
 config I8253
 	bool
 	select CLKSRC_I8253
+	select CLKEVT_I8253
 	select MIPS_EXTERNAL_TIMER
 
 config ZONE_DMA32
diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index 3d2ff57..8d95fe4f 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -4,92 +4,15 @@
  */
 #include <linux/clockchips.h>
 #include <linux/i8253.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/smp.h>
-#include <linux/spinlock.h>
 #include <linux/irq.h>
 
-#include <asm/delay.h>
-#include <asm/io.h>
 #include <asm/time.h>
 
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch(mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_p(0x34, PIT_MODE);
-		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb(LATCH >> 8 , PIT_CH0);	/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_p(0x30, PIT_MODE);
-			outb_p(0, PIT_CH0);
-			outb_p(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_p(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
-	outb(delta >> 8 , PIT_CH0);	/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilites are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_clockevent = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
-	pit_clockevent.event_handler(&pit_clockevent);
+	i8253_clockevent.event_handler(&pit_clockevent);
 
 	return IRQ_HANDLED;
 }
@@ -100,25 +23,9 @@ static struct irqaction irq0  = {
 	.name = "timer"
 };
 
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	struct clock_event_device *cd = &pit_clockevent;
-	unsigned int cpu = smp_processor_id();
-
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	cd->cpumask = cpumask_of(cpu);
-	clockevent_set_clock(cd, CLOCK_TICK_RATE);
-	cd->max_delta_ns = clockevent_delta2ns(0x7FFF, cd);
-	cd->min_delta_ns = clockevent_delta2ns(0xF, cd);
-	clockevents_register_device(cd);
-
+	clockevent_i8253_init(true);
 	setup_irq(0, &irq0);
 }
 

[tip:timers/cleanup] arm: Footbridge: Use common i8253 clockevent

[tip-bot for Thomas Gleixner]

Commit-ID:  cfb5e3d96a8ef12a2aafce2c1cf2ebb849267b16
Gitweb:     http://git.kernel.org/tip/cfb5e3d96a8ef12a2aafce2c1cf2ebb849267b16
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:28 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 24 Jun 2011 16:22:55 +0200

arm: Footbridge: Use common i8253 clockevent

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.241312122@linutronix.de
---
 arch/arm/mach-footbridge/Kconfig     |    1 +
 arch/arm/mach-footbridge/isa-timer.c |   51 +---------------------------------
 2 files changed, 2 insertions(+), 50 deletions(-)

diff --git a/arch/arm/mach-footbridge/Kconfig b/arch/arm/mach-footbridge/Kconfig
index 46adca0..dc26fff 100644
--- a/arch/arm/mach-footbridge/Kconfig
+++ b/arch/arm/mach-footbridge/Kconfig
@@ -5,6 +5,7 @@ menu "Footbridge Implementations"
 config ARCH_CATS
 	bool "CATS"
 	select CLKSRC_I8253
+	select CLKEVT_I8253
 	select FOOTBRIDGE_HOST
 	select ISA
 	select ISA_DMA
diff --git a/arch/arm/mach-footbridge/isa-timer.c b/arch/arm/mach-footbridge/isa-timer.c
index 71fd96d..136eb4b 100644
--- a/arch/arm/mach-footbridge/isa-timer.c
+++ b/arch/arm/mach-footbridge/isa-timer.c
@@ -5,12 +5,10 @@
  *  Copyright (C) 1998 Phil Blundell
  */
 #include <linux/clockchips.h>
-#include <linux/clocksource.h>
 #include <linux/i8253.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
-#include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
 
@@ -19,48 +17,6 @@
 
 #include "common.h"
 
-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);
-}
-
-static int pit_set_next_event(unsigned long delta,
-	struct clock_event_device *evt)
-{
-	return 0;
-}
-
-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)
 {
 	struct clock_event_device *ce = dev_id;
@@ -77,15 +33,10 @@ static struct irqaction pit_timer_irq = {
 
 static void __init isa_timer_init(void)
 {
-	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_i8253_init();
 
 	setup_irq(pit_ce.irq, &pit_timer_irq);
-	clockevents_register_device(&pit_ce);
+	clockevents_i8253_init(false);
 }
 
 struct sys_timer isa_timer = {

[tip:timers/cleanup] i8253: Cleanup outb/inb magic

[tip-bot for Thomas Gleixner]

Commit-ID:  51928d12a6e07a1bd7b38d8b151a50cb24175dd3
Gitweb:     http://git.kernel.org/tip/51928d12a6e07a1bd7b38d8b151a50cb24175dd3
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:30 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 24 Jun 2011 16:22:55 +0200

i8253: Cleanup outb/inb magic

Remove the hysterical outb/inb_pit defines and use outb_p/inb_p in the
code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.348437125@linutronix.de
---
 arch/x86/kernel/apm_32.c |    6 +++---
 include/linux/i8253.h    |    3 ---
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index a30740e..0371c48 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -1220,11 +1220,11 @@ static void reinit_timer(void)
 
 	raw_spin_lock_irqsave(&i8253_lock, flags);
 	/* set the clock to HZ */
-	outb_pit(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
+	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
 	udelay(10);
-	outb_pit(LATCH & 0xff, PIT_CH0);	/* LSB */
+	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
 	udelay(10);
-	outb_pit(LATCH >> 8, PIT_CH0);	/* MSB */
+	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
 	udelay(10);
 	raw_spin_unlock_irqrestore(&i8253_lock, flags);
 #endif
diff --git a/include/linux/i8253.h b/include/linux/i8253.h
index 76039c8..0770fc5 100644
--- a/include/linux/i8253.h
+++ b/include/linux/i8253.h
@@ -20,9 +20,6 @@
 
 #define PIT_LATCH	((PIT_TICK_RATE + HZ/2) / HZ)
 
-#define inb_pit         inb_p
-#define outb_pit        outb_p
-
 extern raw_spinlock_t i8253_lock;
 
 extern void setup_pit_timer(void);

Re: [patch 1/5] i8253: Create common clockevent implementation

[Stijn Devriendt]

> +/*
> + * Initialize the conversion factor and the min/max deltas of the clock event
> + * structure and register the clock event source with the framework.
> + */
> +void __init clockevent_i8253_init(bool oneshot)
> +{
> +       if (oneshot)
> +               i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
> +       /*
> +        * Start pit with the boot cpu mask. x86 might make it global
> +        * when it is used as broadcast device later.
> +        */
> +       i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
> +
> +       clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
> +                                       0xF, 0x7FFF);
> +}
> +#endif
>
Both this function and the i8253_clockevent declaration seem to be missing
from include/linux/i8253.h causing compile failures for at least x86.

I was just trying to compile tip of
git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-devel.git

Should be fixed by applying the following patch.

commit 0c24072a8d580acd5b4fc57009b72b217c0f23d9
Author: Stijn Devriendt <HIGHGuY@gmail.com>
Date:   Sat Jun 25 22:04:53 2011 +0200

    Fix missing declarations of i8253.

    Signed-off-by: Stijn Devriendt <HIGHGuY@gmail.com>

diff --git a/include/linux/i8253.h b/include/linux/i8253.h
index 0770fc5..e6c032f 100644
--- a/include/linux/i8253.h
+++ b/include/linux/i8253.h
@@ -22,6 +22,10 @@

 extern raw_spinlock_t i8253_lock;

+extern struct clock_event_device i8253_clockevent;
+
 extern void setup_pit_timer(void);

+extern void clockevent_i8253_init(bool oneshot);
+
 #endif /* __LINUX_I8253_H */

Re: [patch 1/5] i8253: Create common clockevent implementation

[Masami Hiramatsu]

(2011/06/26 5:03), Stijn Devriendt wrote:
>> +/*
>> + * Initialize the conversion factor and the min/max deltas of the clock event
>> + * structure and register the clock event source with the framework.
>> + */
>> +void __init clockevent_i8253_init(bool oneshot)
>> +{
>> +       if (oneshot)
>> +               i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
>> +       /*
>> +        * Start pit with the boot cpu mask. x86 might make it global
>> +        * when it is used as broadcast device later.
>> +        */
>> +       i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
>> +
>> +       clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
>> +                                       0xF, 0x7FFF);
>> +}
>> +#endif
>>
> Both this function and the i8253_clockevent declaration seem to be missing
> from include/linux/i8253.h causing compile failures for at least x86.
> 
> I was just trying to compile tip of
> git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-devel.git

I've met same problem on latest tip tree.

> Should be fixed by applying the following patch.

We still need to expose clocksource_i8253_init() too
for CONFIG_X86_64=n.
So, could you update your patch (and send it as a patch mail)?

Thank you,

> 
> commit 0c24072a8d580acd5b4fc57009b72b217c0f23d9
> Author: Stijn Devriendt <HIGHGuY@gmail.com>
> Date:   Sat Jun 25 22:04:53 2011 +0200
> 
>     Fix missing declarations of i8253.
> 
>     Signed-off-by: Stijn Devriendt <HIGHGuY@gmail.com>
> 
> diff --git a/include/linux/i8253.h b/include/linux/i8253.h
> index 0770fc5..e6c032f 100644
> --- a/include/linux/i8253.h
> +++ b/include/linux/i8253.h
> @@ -22,6 +22,10 @@
> 
>  extern raw_spinlock_t i8253_lock;
> 
> +extern struct clock_event_device i8253_clockevent;
> +
>  extern void setup_pit_timer(void);
> 
> +extern void clockevent_i8253_init(bool oneshot);
> +
>  #endif /* __LINUX_I8253_H */


-- 
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com

[tip:timers/cleanup] i8253: Create common clockevent implementation

[tip-bot for Thomas Gleixner]

Commit-ID:  e6220bdc9485c5ea972f9e0e6d062a05934bb74b
Gitweb:     http://git.kernel.org/tip/e6220bdc9485c5ea972f9e0e6d062a05934bb74b
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:25 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 1 Jul 2011 10:37:14 +0200

i8253: Create common clockevent implementation

arm, mips and x86 implement i8253 based clockevents. All the same code
copied. Create a common implementation in drivers/clocksource/i8253.c.

About time to rename drivers/clocksource/ to something else.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130621.921710458@linutronix.de

---
 drivers/clocksource/Kconfig |    5 ++-
 drivers/clocksource/i8253.c |  101 ++++++++++++++++++++++++++++++++++++++++---
 include/linux/i8253.h       |    2 +
 3 files changed, 100 insertions(+), 8 deletions(-)

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 330343b..d8d3e02 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -1,11 +1,14 @@
 config CLKSRC_I8253
 	bool
 
+config CLKEVT_I8253
+	bool
+
 config I8253_LOCK
 	bool
 
 config CLKBLD_I8253
-	def_bool y if CLKSRC_I8253 || I8253_LOCK
+	def_bool y if CLKSRC_I8253 || CLKEVT_I8253 || I8253_LOCK
 
 config CLKSRC_MMIO
 	bool
diff --git a/drivers/clocksource/i8253.c b/drivers/clocksource/i8253.c
index e594f52..27c49e6 100644
--- a/drivers/clocksource/i8253.c
+++ b/drivers/clocksource/i8253.c
@@ -1,13 +1,14 @@
 /*
  * i8253 PIT clocksource
  */
-#include <linux/clocksource.h>
+#include <linux/clockchips.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
 #include <linux/module.h>
 #include <linux/i8253.h>
+#include <linux/smp.h>
 
 /*
  * Protects access to I/O ports
@@ -47,15 +48,15 @@ static cycle_t i8253_read(struct clocksource *cs)
 	 * count), it cannot be newer.
 	 */
 	jifs = jiffies;
-	outb_pit(0x00, PIT_MODE);	/* latch the count ASAP */
-	count = inb_pit(PIT_CH0);	/* read the latched count */
-	count |= inb_pit(PIT_CH0) << 8;
+	outb_p(0x00, PIT_MODE);	/* latch the count ASAP */
+	count = inb_p(PIT_CH0);	/* read the latched count */
+	count |= inb_p(PIT_CH0) << 8;
 
 	/* VIA686a test code... reset the latch if count > max + 1 */
 	if (count > LATCH) {
-		outb_pit(0x34, PIT_MODE);
-		outb_pit(PIT_LATCH & 0xff, PIT_CH0);
-		outb_pit(PIT_LATCH >> 8, PIT_CH0);
+		outb_p(0x34, PIT_MODE);
+		outb_p(PIT_LATCH & 0xff, PIT_CH0);
+		outb_p(PIT_LATCH >> 8, PIT_CH0);
 		count = PIT_LATCH - 1;
 	}
 
@@ -97,3 +98,89 @@ int __init clocksource_i8253_init(void)
 	return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
 }
 #endif
+
+#ifdef CONFIG_CLKEVT_I8253
+/*
+ * Initialize the PIT timer.
+ *
+ * This is also called after resume to bring the PIT into operation again.
+ */
+static void init_pit_timer(enum clock_event_mode mode,
+			   struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		/* binary, mode 2, LSB/MSB, ch 0 */
+		outb_p(0x34, PIT_MODE);
+		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
+		outb_p(LATCH >> 8 , PIT_CH0);		/* MSB */
+		break;
+
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	case CLOCK_EVT_MODE_UNUSED:
+		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
+		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
+			outb_p(0x30, PIT_MODE);
+			outb_p(0, PIT_CH0);
+			outb_p(0, PIT_CH0);
+		}
+		break;
+
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* One shot setup */
+		outb_p(0x38, PIT_MODE);
+		break;
+
+	case CLOCK_EVT_MODE_RESUME:
+		/* Nothing to do here */
+		break;
+	}
+	raw_spin_unlock(&i8253_lock);
+}
+
+/*
+ * Program the next event in oneshot mode
+ *
+ * Delta is given in PIT ticks
+ */
+static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
+	outb_p(delta >> 8 , PIT_CH0);		/* MSB */
+	raw_spin_unlock(&i8253_lock);
+
+	return 0;
+}
+
+/*
+ * On UP the PIT can serve all of the possible timer functions. On SMP systems
+ * it can be solely used for the global tick.
+ */
+struct clock_event_device i8253_clockevent = {
+	.name		= "pit",
+	.features	= CLOCK_EVT_FEAT_PERIODIC,
+	.set_mode	= init_pit_timer,
+	.set_next_event = pit_next_event,
+};
+
+/*
+ * Initialize the conversion factor and the min/max deltas of the clock event
+ * structure and register the clock event source with the framework.
+ */
+void __init clockevent_i8253_init(bool oneshot)
+{
+	if (oneshot)
+		i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
+	/*
+	 * Start pit with the boot cpu mask. x86 might make it global
+	 * when it is used as broadcast device later.
+	 */
+	i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
+
+	clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
+					0xF, 0x7FFF);
+}
+#endif
diff --git a/include/linux/i8253.h b/include/linux/i8253.h
index 76039c8..487d50c 100644
--- a/include/linux/i8253.h
+++ b/include/linux/i8253.h
@@ -24,6 +24,8 @@
 #define outb_pit        outb_p
 
 extern raw_spinlock_t i8253_lock;
+extern struct clock_event_device i8253_clockevent;
+extern void clockevent_i8253_init(bool oneshot);
 
 extern void setup_pit_timer(void);
 

[tip:timers/cleanup] x86: Use common i8253 clockevent

[tip-bot for Thomas Gleixner]

Commit-ID:  0a779c571314b7951ff12edac80aa0cbe7c12b6e
Gitweb:     http://git.kernel.org/tip/0a779c571314b7951ff12edac80aa0cbe7c12b6e
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:26 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 1 Jul 2011 10:37:14 +0200

x86: Use common i8253 clockevent

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.026152527@linutronix.de
---
 arch/x86/Kconfig        |    2 +-
 arch/x86/kernel/i8253.c |   93 ++---------------------------------------------
 2 files changed, 4 insertions(+), 91 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2dd95b5..26a14b4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -71,7 +71,7 @@ config X86
 	select IRQ_FORCED_THREADING
 	select USE_GENERIC_SMP_HELPERS if SMP
 	select HAVE_BPF_JIT if (X86_64 && NET)
-	select I8253_LOCK
+	select CLKEVT_I8253
 
 config INSTRUCTION_DECODER
 	def_bool (KPROBES || PERF_EVENTS)
diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c
index 5783e6d..f2b96de 100644
--- a/arch/x86/kernel/i8253.c
+++ b/arch/x86/kernel/i8253.c
@@ -3,15 +3,9 @@
  *
  */
 #include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/spinlock.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/timex.h>
-#include <linux/delay.h>
 #include <linux/i8253.h>
-#include <linux/init.h>
-#include <linux/io.h>
 
 #include <asm/hpet.h>
 #include <asm/time.h>
@@ -23,91 +17,10 @@
  */
 struct clock_event_device *global_clock_event;
 
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_pit(0x34, PIT_MODE);
-		outb_pit(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb_pit(LATCH >> 8 , PIT_CH0);		/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_pit(0x30, PIT_MODE);
-			outb_pit(0, PIT_CH0);
-			outb_pit(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_pit(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_pit(delta & 0xff , PIT_CH0);	/* LSB */
-	outb_pit(delta >> 8 , PIT_CH0);		/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilities are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_ce = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	pit_ce.cpumask = cpumask_of(smp_processor_id());
-
-	clockevents_config_and_register(&pit_ce, CLOCK_TICK_RATE, 0xF, 0x7FFF);
-	global_clock_event = &pit_ce;
+	clockevent_i8253_init(true);
+	global_clock_event = &i8253_clockevent;
 }
 
 #ifndef CONFIG_X86_64
@@ -121,7 +34,7 @@ static int __init init_pit_clocksource(void)
 	  * - when local APIC timer is active (PIT is switched off)
 	  */
 	if (num_possible_cpus() > 1 || is_hpet_enabled() ||
-	    pit_ce.mode != CLOCK_EVT_MODE_PERIODIC)
+	    i8253_clockevent.mode != CLOCK_EVT_MODE_PERIODIC)
 		return 0;
 
 	return clocksource_i8253_init();

[tip:timers/cleanup] mips: Use common i8253 clockevent

[tip-bot for Thomas Gleixner]

Commit-ID:  2d02612f61cc15b2025c90e32ed4a43eaa6753cd
Gitweb:     http://git.kernel.org/tip/2d02612f61cc15b2025c90e32ed4a43eaa6753cd
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:27 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 1 Jul 2011 10:37:14 +0200

mips: Use common i8253 clockevent

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.133068765@linutronix.de
---
 arch/mips/Kconfig        |    1 +
 arch/mips/kernel/i8253.c |   97 +---------------------------------------------
 2 files changed, 3 insertions(+), 95 deletions(-)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 45f7aac..6cb60ad 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2391,6 +2391,7 @@ config MMU
 config I8253
 	bool
 	select CLKSRC_I8253
+	select CLKEVT_I8253
 	select MIPS_EXTERNAL_TIMER
 
 config ZONE_DMA32
diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index 3d2ff57..8d95fe4f 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -4,92 +4,15 @@
  */
 #include <linux/clockchips.h>
 #include <linux/i8253.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/smp.h>
-#include <linux/spinlock.h>
 #include <linux/irq.h>
 
-#include <asm/delay.h>
-#include <asm/io.h>
 #include <asm/time.h>
 
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
-			   struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-
-	switch(mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* binary, mode 2, LSB/MSB, ch 0 */
-		outb_p(0x34, PIT_MODE);
-		outb_p(LATCH & 0xff , PIT_CH0);	/* LSB */
-		outb(LATCH >> 8 , PIT_CH0);	/* MSB */
-		break;
-
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-		if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
-		    evt->mode == CLOCK_EVT_MODE_ONESHOT) {
-			outb_p(0x30, PIT_MODE);
-			outb_p(0, PIT_CH0);
-			outb_p(0, PIT_CH0);
-		}
-		break;
-
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* One shot setup */
-		outb_p(0x38, PIT_MODE);
-		break;
-
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
-	raw_spin_unlock(&i8253_lock);
-}
-
-/*
- * Program the next event in oneshot mode
- *
- * Delta is given in PIT ticks
- */
-static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
-{
-	raw_spin_lock(&i8253_lock);
-	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
-	outb(delta >> 8 , PIT_CH0);	/* MSB */
-	raw_spin_unlock(&i8253_lock);
-
-	return 0;
-}
-
-/*
- * On UP the PIT can serve all of the possible timer functions. On SMP systems
- * it can be solely used for the global tick.
- *
- * The profiling and update capabilites are switched off once the local apic is
- * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
- * !using_apic_timer decisions in do_timer_interrupt_hook()
- */
-static struct clock_event_device pit_clockevent = {
-	.name		= "pit",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode	= init_pit_timer,
-	.set_next_event = pit_next_event,
-	.irq		= 0,
-};
-
 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
-	pit_clockevent.event_handler(&pit_clockevent);
+	i8253_clockevent.event_handler(&pit_clockevent);
 
 	return IRQ_HANDLED;
 }
@@ -100,25 +23,9 @@ static struct irqaction irq0  = {
 	.name = "timer"
 };
 
-/*
- * Initialize the conversion factor and the min/max deltas of the clock event
- * structure and register the clock event source with the framework.
- */
 void __init setup_pit_timer(void)
 {
-	struct clock_event_device *cd = &pit_clockevent;
-	unsigned int cpu = smp_processor_id();
-
-	/*
-	 * Start pit with the boot cpu mask and make it global after the
-	 * IO_APIC has been initialized.
-	 */
-	cd->cpumask = cpumask_of(cpu);
-	clockevent_set_clock(cd, CLOCK_TICK_RATE);
-	cd->max_delta_ns = clockevent_delta2ns(0x7FFF, cd);
-	cd->min_delta_ns = clockevent_delta2ns(0xF, cd);
-	clockevents_register_device(cd);
-
+	clockevent_i8253_init(true);
 	setup_irq(0, &irq0);
 }
 

[tip:timers/cleanup] arm: Footbridge: Use common i8253 clockevent

[tip-bot for Thomas Gleixner]

Commit-ID:  8560a6cfc9818edde1fd8677961714b264ffa03d
Gitweb:     http://git.kernel.org/tip/8560a6cfc9818edde1fd8677961714b264ffa03d
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:28 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 1 Jul 2011 10:37:14 +0200

arm: Footbridge: Use common i8253 clockevent

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.241312122@linutronix.de
---
 arch/arm/mach-footbridge/Kconfig     |    1 +
 arch/arm/mach-footbridge/isa-timer.c |   55 ++--------------------------------
 2 files changed, 4 insertions(+), 52 deletions(-)

diff --git a/arch/arm/mach-footbridge/Kconfig b/arch/arm/mach-footbridge/Kconfig
index 46adca0..dc26fff 100644
--- a/arch/arm/mach-footbridge/Kconfig
+++ b/arch/arm/mach-footbridge/Kconfig
@@ -5,6 +5,7 @@ menu "Footbridge Implementations"
 config ARCH_CATS
 	bool "CATS"
 	select CLKSRC_I8253
+	select CLKEVT_I8253
 	select FOOTBRIDGE_HOST
 	select ISA
 	select ISA_DMA
diff --git a/arch/arm/mach-footbridge/isa-timer.c b/arch/arm/mach-footbridge/isa-timer.c
index 71fd96d..c40bb41 100644
--- a/arch/arm/mach-footbridge/isa-timer.c
+++ b/arch/arm/mach-footbridge/isa-timer.c
@@ -5,12 +5,10 @@
  *  Copyright (C) 1998 Phil Blundell
  */
 #include <linux/clockchips.h>
-#include <linux/clocksource.h>
 #include <linux/i8253.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
-#include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
 
@@ -19,48 +17,6 @@
 
 #include "common.h"
 
-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);
-}
-
-static int pit_set_next_event(unsigned long delta,
-	struct clock_event_device *evt)
-{
-	return 0;
-}
-
-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)
 {
 	struct clock_event_device *ce = dev_id;
@@ -72,20 +28,15 @@ static struct irqaction pit_timer_irq = {
 	.name		= "pit",
 	.handler	= pit_timer_interrupt,
 	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
-	.dev_id		= &pit_ce,
+	.dev_id		= &i8253_clockevent,
 };
 
 static void __init isa_timer_init(void)
 {
-	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_i8253_init();
 
-	setup_irq(pit_ce.irq, &pit_timer_irq);
-	clockevents_register_device(&pit_ce);
+	setup_irq(i8253_clockevent.irq, &pit_timer_irq);
+	clockevent_i8253_init(false);
 }
 
 struct sys_timer isa_timer = {

[tip:timers/cleanup] i8253: Cleanup outb/inb magic

[tip-bot for Thomas Gleixner]

Commit-ID:  01898e3e29ea8242d81923da11ce88ba71290a48
Gitweb:     http://git.kernel.org/tip/01898e3e29ea8242d81923da11ce88ba71290a48
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 9 Jun 2011 13:08:30 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 1 Jul 2011 10:37:15 +0200

i8253: Cleanup outb/inb magic

Remove the hysterical outb/inb_pit defines and use outb_p/inb_p in the
code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130622.348437125@linutronix.de
---
 arch/x86/kernel/apm_32.c |    6 +++---
 include/linux/i8253.h    |    3 ---
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index a30740e..0371c48 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -1220,11 +1220,11 @@ static void reinit_timer(void)
 
 	raw_spin_lock_irqsave(&i8253_lock, flags);
 	/* set the clock to HZ */
-	outb_pit(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
+	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
 	udelay(10);
-	outb_pit(LATCH & 0xff, PIT_CH0);	/* LSB */
+	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
 	udelay(10);
-	outb_pit(LATCH >> 8, PIT_CH0);	/* MSB */
+	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
 	udelay(10);
 	raw_spin_unlock_irqrestore(&i8253_lock, flags);
 #endif
diff --git a/include/linux/i8253.h b/include/linux/i8253.h
index 487d50c..e6bb36a 100644
--- a/include/linux/i8253.h
+++ b/include/linux/i8253.h
@@ -20,9 +20,6 @@
 
 #define PIT_LATCH	((PIT_TICK_RATE + HZ/2) / HZ)
 
-#define inb_pit         inb_p
-#define outb_pit        outb_p
-
 extern raw_spinlock_t i8253_lock;
 extern struct clock_event_device i8253_clockevent;
 extern void clockevent_i8253_init(bool oneshot);