Commit b3402cf5 authored by Tony Lindgren's avatar Tony Lindgren Committed by Russell King
Browse files

[PATCH] ARM: 2771/1: Dynamic Tick support for OMAP, take 4



Patch from Tony Lindgren

This patch adds support for Dynamic Tick Timer for OMAP.
This patch is an updated version of ARM patch 2642/1 to
make it work with the already integrated generic ARM
dyntick support.
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 20f720cc
......@@ -41,7 +41,9 @@
#include <linux/pm.h>
#include <asm/io.h>
#include <asm/mach/time.h>
#include <asm/mach-types.h>
#include <asm/arch/omap16xx.h>
#include <asm/arch/pm.h>
#include <asm/arch/mux.h>
......@@ -80,13 +82,13 @@ void omap_pm_idle(void)
return;
}
mask32 = omap_readl(ARM_SYSST);
local_fiq_enable();
local_irq_enable();
#if defined(CONFIG_OMAP_32K_TIMER) && defined(CONFIG_NO_IDLE_HZ)
/* Override timer to use VST for the next cycle */
omap_32k_timer_next_vst_interrupt();
#endif
/*
* Since an interrupt may set up a timer, we don't want to
* reprogram the hardware timer with interrupts enabled.
* Re-enable interrupts only after returning from idle.
*/
timer_dyn_reprogram();
if ((mask32 & DSP_IDLE) == 0) {
__asm__ volatile ("mcr p15, 0, r0, c7, c0, 4");
......@@ -102,6 +104,8 @@ void omap_pm_idle(void)
func_ptr();
}
local_fiq_enable();
local_irq_enable();
}
/*
......
......@@ -4,7 +4,7 @@
* OMAP Timers
*
* Copyright (C) 2004 Nokia Corporation
* Partial timer rewrite and additional VST timer support by
* Partial timer rewrite and additional dynamic tick timer support by
* Tony Lindgen <tony@atomide.com> and
* Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
*
......@@ -261,7 +261,6 @@ unsigned long long sched_clock(void)
* so with HZ = 100, TVR = 327.68.
*/
#define OMAP_32K_TIMER_TICK_PERIOD ((32768 / HZ) - 1)
#define MAX_SKIP_JIFFIES 25
#define TIMER_32K_SYNCHRONIZED 0xfffbc410
#define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate) \
......@@ -347,6 +346,42 @@ static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id,
return IRQ_HANDLED;
}
#ifdef CONFIG_NO_IDLE_HZ
/*
* Programs the next timer interrupt needed. Called when dynamic tick is
* enabled, and to reprogram the ticks to skip from pm_idle. Note that
* we can keep the timer continuous, and don't need to set it to run in
* one-shot mode. This is because the timer will get reprogrammed again
* after next interrupt.
*/
void omap_32k_timer_reprogram(unsigned long next_tick)
{
omap_32k_timer_start(JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1);
}
static struct irqaction omap_32k_timer_irq;
extern struct timer_update_handler timer_update;
static int omap_32k_timer_enable_dyn_tick(void)
{
/* No need to reprogram timer, just use the next interrupt */
return 0;
}
static int omap_32k_timer_disable_dyn_tick(void)
{
omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
return 0;
}
static struct dyn_tick_timer omap_dyn_tick_timer = {
.enable = omap_32k_timer_enable_dyn_tick,
.disable = omap_32k_timer_disable_dyn_tick,
.reprogram = omap_32k_timer_reprogram,
.handler = omap_32k_timer_interrupt,
};
#endif /* CONFIG_NO_IDLE_HZ */
static struct irqaction omap_32k_timer_irq = {
.name = "32KHz timer",
.flags = SA_INTERRUPT | SA_TIMER,
......@@ -355,6 +390,11 @@ static struct irqaction omap_32k_timer_irq = {
static __init void omap_init_32k_timer(void)
{
#ifdef CONFIG_NO_IDLE_HZ
omap_timer.dyn_tick = &omap_dyn_tick_timer;
#endif
setup_irq(INT_OS_TIMER, &omap_32k_timer_irq);
omap_timer.offset = omap_32k_timer_gettimeoffset;
omap_32k_last_tick = omap_32k_sync_timer_read();
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment