[PATCH -rt] Resolve -rt OMAP conflicts
From: Kevin Hilman
Date: Tue May 22 2007 - 19:49:19 EST
This patch removes all the OMAP clocksource/clockevent stuff from the
-rt patch since it is now all in the OMAP tree.
It also removes the few raw_spinlock additions to OMAP specific files
which will be revisited/resumitted if necessary. I currently believe
that all of these raw spinlocks are no longer necessary.
Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxx>
--- linux/arch/arm/Kconfig
+++ linux.orig/arch/arm/Kconfig
@@ -363,7 +363,6 @@
config ARCH_OMAP
bool "TI OMAP"
select GENERIC_GPIO
- select GENERIC_TIME
help
Support for TI's OMAP platform (OMAP1 and OMAP2).
reverted:
--- linux/arch/arm/mach-omap1/pm.c
+++ linux.orig/arch/arm/mach-omap1/pm.c
@@ -120,7 +120,7 @@
local_irq_disable();
local_fiq_disable();
+ if (need_resched()) {
- if (need_resched() || need_resched_delayed()) {
local_fiq_enable();
local_irq_enable();
return;
reverted:
--- linux/arch/arm/mach-omap1/time.c
+++ linux.orig/arch/arm/mach-omap1/time.c
@@ -39,10 +39,6 @@
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/clocksource.h>
-#include <linux/clockchips.h>
#include <asm/system.h>
#include <asm/hardware.h>
@@ -52,7 +48,13 @@
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
+struct sys_timer omap_timer;
+/*
+ * ---------------------------------------------------------------------------
+ * MPU timer
+ * ---------------------------------------------------------------------------
+ */
#define OMAP_MPU_TIMER_BASE OMAP_MPU_TIMER1_BASE
#define OMAP_MPU_TIMER_OFFSET 0x100
@@ -86,6 +88,21 @@
return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
}
+/*
+ * MPU_TICKS_PER_SEC must be an even number, otherwise machinecycles_to_usecs
+ * will break. On P2, the timer count rate is 6.5 MHz after programming PTV
+ * with 0. This divides the 13MHz input by 2, and is undocumented.
+ */
+#if defined(CONFIG_MACH_OMAP_PERSEUS2) || defined(CONFIG_MACH_OMAP_FSAMPLE)
+/* REVISIT: This ifdef construct should be replaced by a query to clock
+ * framework to see if timer base frequency is 12.0, 13.0 or 19.2 MHz.
+ */
+#define MPU_TICKS_PER_SEC (13000000 / 2)
+#else
+#define MPU_TICKS_PER_SEC (12000000 / 2)
+#endif
+
+#define MPU_TIMER_TICK_PERIOD ((MPU_TICKS_PER_SEC / HZ) - 1)
typedef struct {
u32 cntl; /* CNTL_TIMER, R/W */
@@ -103,164 +120,98 @@
return timer->read_tim;
}
+static inline void omap_mpu_timer_start(int nr, unsigned long load_val)
-static inline void omap_mpu_set_autoreset(int nr)
-{
- volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr);
-
- timer->cntl = timer->cntl | MPU_TIMER_AR;
-}
-
-static inline void omap_mpu_remove_autoreset(int nr)
-{
- volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr);
-
- timer->cntl = timer->cntl & ~MPU_TIMER_AR;
-}
-
-static inline void omap_mpu_timer_start(int nr, unsigned long load_val,
- int autoreset)
{
volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr);
- unsigned int timerflags = (MPU_TIMER_CLOCK_ENABLE | MPU_TIMER_ST);
-
- if (autoreset) timerflags |= MPU_TIMER_AR;
timer->cntl = MPU_TIMER_CLOCK_ENABLE;
udelay(1);
timer->load_tim = load_val;
udelay(1);
+ timer->cntl = (MPU_TIMER_CLOCK_ENABLE | MPU_TIMER_AR | MPU_TIMER_ST);
- timer->cntl = timerflags;
-}
-
-/*
- * ---------------------------------------------------------------------------
- * MPU timer 1 ... count down to zero, interrupt, reload
- * ---------------------------------------------------------------------------
- */
-static int omap_mpu_set_next_event(unsigned long cycles,
- struct clock_event_device *evt)
-{
- omap_mpu_timer_start(0, cycles, 0);
- return 0;
}
+unsigned long omap_mpu_timer_ticks_to_usecs(unsigned long nr_ticks)
-static void omap_mpu_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
-{
- switch (mode) {
- case CLOCK_EVT_MODE_PERIODIC:
- omap_mpu_set_autoreset(0);
- break;
- case CLOCK_EVT_MODE_ONESHOT:
- omap_mpu_remove_autoreset(0);
- break;
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- break;
- }
-}
-
-static struct clock_event_device clockevent_mpu_timer1 = {
- .name = "mpu_timer1",
- .features = CLOCK_EVT_FEAT_PERIODIC, CLOCK_EVT_FEAT_ONESHOT,
- .shift = 32,
- .set_next_event = omap_mpu_set_next_event,
- .set_mode = omap_mpu_set_mode,
-};
-
-static irqreturn_t omap_mpu_timer1_interrupt(int irq, void *dev_id)
{
+ unsigned long long nsec;
- struct clock_event_device *evt = &clockevent_mpu_timer1;
-
- evt->event_handler(evt);
+ nsec = cycles_2_ns((unsigned long long)nr_ticks);
+ return (unsigned long)nsec / 1000;
- return IRQ_HANDLED;
}
+/*
+ * Last processed system timer interrupt
+ */
+static unsigned long omap_mpu_timer_last = 0;
-static struct irqaction omap_mpu_timer1_irq = {
- .name = "mpu_timer1",
- .flags = IRQF_DISABLED | IRQF_TIMER,
- .handler = omap_mpu_timer1_interrupt,
-};
+/*
+ * Returns elapsed usecs since last system timer interrupt
+ */
+static unsigned long omap_mpu_timer_gettimeoffset(void)
-static __init void omap_init_mpu_timer(unsigned long rate)
{
+ unsigned long now = 0 - omap_mpu_timer_read(0);
+ unsigned long elapsed = now - omap_mpu_timer_last;
- set_cyc2ns_scale(rate / 1000);
-
- setup_irq(INT_TIMER1, &omap_mpu_timer1_irq);
- omap_mpu_timer_start(0, (rate / HZ) - 1, 1);
-
- clockevent_mpu_timer1.mult = div_sc(rate, NSEC_PER_SEC,
- clockevent_mpu_timer1.shift);
- clockevent_mpu_timer1.max_delta_ns =
- clockevent_delta2ns(-1, &clockevent_mpu_timer1);
- clockevent_mpu_timer1.min_delta_ns =
- clockevent_delta2ns(1, &clockevent_mpu_timer1);
+ return omap_mpu_timer_ticks_to_usecs(elapsed);
- clockevent_mpu_timer1.cpumask = cpumask_of_cpu(0);
- clockevents_register_device(&clockevent_mpu_timer1);
}
-
/*
+ * Elapsed time between interrupts is calculated using timer0.
+ * Latency during the interrupt is calculated using timer1.
+ * Both timer0 and timer1 are counting at 6MHz (P2 6.5MHz).
- * ---------------------------------------------------------------------------
- * MPU timer 2 ... free running 32-bit clock source and scheduler clock
- * ---------------------------------------------------------------------------
*/
+static irqreturn_t omap_mpu_timer_interrupt(int irq, void *dev_id)
+{
+ unsigned long now, latency;
+ write_seqlock(&xtime_lock);
+ now = 0 - omap_mpu_timer_read(0);
+ latency = MPU_TICKS_PER_SEC / HZ - omap_mpu_timer_read(1);
+ omap_mpu_timer_last = now - latency;
+ timer_tick();
+ write_sequnlock(&xtime_lock);
-static unsigned long omap_mpu_timer2_overflows;
-static irqreturn_t omap_mpu_timer2_interrupt(int irq, void *dev_id)
-{
- omap_mpu_timer2_overflows++;
return IRQ_HANDLED;
}
+static struct irqaction omap_mpu_timer_irq = {
+ .name = "mpu timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+ .handler = omap_mpu_timer_interrupt,
-static struct irqaction omap_mpu_timer2_irq = {
- .name = "mpu_timer2",
- .flags = IRQF_DISABLED,
- .handler = omap_mpu_timer2_interrupt,
};
+static unsigned long omap_mpu_timer1_overflows;
+static irqreturn_t omap_mpu_timer1_interrupt(int irq, void *dev_id)
-static cycle_t mpu_read(void)
{
+ omap_mpu_timer1_overflows++;
+ return IRQ_HANDLED;
- return ~omap_mpu_timer_read(1);
}
+static struct irqaction omap_mpu_timer1_irq = {
+ .name = "mpu timer1 overflow",
+ .flags = IRQF_DISABLED,
+ .handler = omap_mpu_timer1_interrupt,
-static struct clocksource clocksource_mpu = {
- .name = "mpu_timer2",
- .rating = 300,
- .read = mpu_read,
- .mask = CLOCKSOURCE_MASK(32),
- .shift = 24,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
+static __init void omap_init_mpu_timer(void)
-static void __init omap_init_clocksource(unsigned long rate)
{
+ set_cyc2ns_scale(MPU_TICKS_PER_SEC / 1000);
+ omap_timer.offset = omap_mpu_timer_gettimeoffset;
+ setup_irq(INT_TIMER1, &omap_mpu_timer1_irq);
+ setup_irq(INT_TIMER2, &omap_mpu_timer_irq);
+ omap_mpu_timer_start(0, 0xffffffff);
+ omap_mpu_timer_start(1, MPU_TIMER_TICK_PERIOD);
- static char err[] __initdata = KERN_ERR
- "%s: can't register clocksource!\n";
-
- clocksource_mpu.mult
- = clocksource_khz2mult(rate/1000, clocksource_mpu.shift);
-
- setup_irq(INT_TIMER2, &omap_mpu_timer2_irq);
- omap_mpu_timer_start(1, ~0, 1);
-
- if (clocksource_register(&clocksource_mpu))
- printk(err, clocksource_mpu.name);
}
-
/*
* Scheduler clock - returns current time in nanosec units.
*/
unsigned long long sched_clock(void)
{
+ unsigned long ticks = 0 - omap_mpu_timer_read(0);
- unsigned long ticks = 0 - omap_mpu_timer_read(1);
unsigned long long ticks64;
+ ticks64 = omap_mpu_timer1_overflows;
- ticks64 = omap_mpu_timer2_overflows;
ticks64 <<= 32;
ticks64 |= ticks;
@@ -274,21 +225,10 @@
*/
static void __init omap_timer_init(void)
{
+ omap_init_mpu_timer();
- struct clk *ck_ref = clk_get(NULL, "ck_ref");
- unsigned long rate;
-
- BUG_ON(IS_ERR(ck_ref));
-
- rate = clk_get_rate(ck_ref);
- clk_put(ck_ref);
-
- /* PTV = 0 */
- rate /= 2;
-
- omap_init_mpu_timer(rate);
- omap_init_clocksource(rate);
}
struct sys_timer omap_timer = {
.init = omap_timer_init,
+ .offset = NULL, /* Initialized later */
};
reverted:
--- linux/arch/arm/mach-omap2/pm.c
+++ linux.orig/arch/arm/mach-omap2/pm.c
@@ -53,7 +53,7 @@
{
local_irq_disable();
local_fiq_disable();
+ if (need_resched()) {
- if (need_resched() || need_resched_delayed()) {
local_fiq_enable();
local_irq_enable();
return;
reverted:
--- linux/arch/arm/plat-omap/Kconfig
+++ linux.orig/arch/arm/plat-omap/Kconfig
@@ -11,7 +11,6 @@
config ARCH_OMAP1
bool "TI OMAP1"
- select GENERIC_CLOCKEVENTS
config ARCH_OMAP2
bool "TI OMAP2"
reverted:
--- linux/arch/arm/plat-omap/clock.c
+++ linux.orig/arch/arm/plat-omap/clock.c
@@ -29,7 +29,7 @@
static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
+static DEFINE_SPINLOCK(clockfw_lock);
-static DEFINE_RAW_SPINLOCK(clockfw_lock);
static struct clk_functions *arch_clock;
reverted:
--- linux/arch/arm/plat-omap/common.c
+++ linux.orig/arch/arm/plat-omap/common.c
@@ -156,53 +156,3 @@
return add_preferred_console("ttyS", line, opt);
}
console_initcall(omap_add_serial_console);
-
-
-/*
- * 32KHz clocksource ... always available, on pretty most chips except
- * OMAP 730 and 1510. Other timers could be used as clocksources, with
- * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
- * but systems won't necessarily want to spend resources that way.
- */
-
-#if defined(CONFIG_ARCH_OMAP16XX)
-#define TIMER_32K_SYNCHRONIZED 0xfffbc410
-#elif defined(CONFIG_ARCH_OMAP24XX)
-#define TIMER_32K_SYNCHRONIZED 0x48004010
-#endif
-
-#ifdef TIMER_32K_SYNCHRONIZED
-
-#include <linux/clocksource.h>
-
-static cycle_t omap_32k_read(void)
-{
- return omap_readl(TIMER_32K_SYNCHRONIZED);
-}
-
-static struct clocksource clocksource_32k = {
- .name = "32k_counter",
- .rating = 250,
- .read = omap_32k_read,
- .mask = CLOCKSOURCE_MASK(32),
- .shift = 10,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-static int __init omap_init_clocksource_32k(void)
-{
- static char err[] __initdata = KERN_ERR
- "%s: can't register clocksource!\n";
-
- if (cpu_is_omap16xx() || cpu_is_omap24xx()) {
- clocksource_32k.mult = clocksource_hz2mult(32768,
- clocksource_32k.shift);
-
- if (clocksource_register(&clocksource_32k))
- printk(err, clocksource_32k.name);
- }
- return 0;
-}
-arch_initcall(omap_init_clocksource_32k);
-
-#endif /* TIMER_32K_SYNCHRONIZED */
reverted:
--- linux/arch/arm/plat-omap/dma.c
+++ linux.orig/arch/arm/plat-omap/dma.c
@@ -982,7 +982,7 @@
/*----------------------------------------------------------------------------*/
static struct lcd_dma_info {
+ spinlock_t lock;
- raw_spinlock_t lock;
int reserved;
void (* callback)(u16 status, void *data);
void *cb_data;
reverted:
--- linux/arch/arm/plat-omap/gpio.c
+++ linux.orig/arch/arm/plat-omap/gpio.c
@@ -120,7 +120,7 @@
u32 reserved_map;
u32 suspend_wakeup;
u32 saved_wakeup;
+ spinlock_t lock;
- raw_spinlock_t lock;
};
#define METHOD_MPUIO 0
reverted:
--- linux/arch/arm/plat-omap/mux.c
+++ linux.orig/arch/arm/plat-omap/mux.c
@@ -56,7 +56,7 @@
*/
int __init_or_module omap_cfg_reg(const unsigned long index)
{
+ static DEFINE_SPINLOCK(mux_spin_lock);
- static DEFINE_RAW_SPINLOCK(mux_spin_lock);
unsigned long flags;
struct pin_config *cfg;
reverted:
--- linux/arch/arm/plat-omap/timer32k.c
+++ linux.orig/arch/arm/plat-omap/timer32k.c
@@ -42,8 +42,6 @@
#include <linux/spinlock.h>
#include <linux/err.h>
#include <linux/clk.h>
-#include <linux/clocksource.h>
-#include <linux/clockchips.h>
#include <asm/system.h>
#include <asm/hardware.h>
@@ -82,13 +80,13 @@
#define OMAP1_32K_TIMER_TVR 0x00
#define OMAP1_32K_TIMER_TCR 0x04
+#define OMAP_32K_TICKS_PER_HZ (32768 / HZ)
-#define OMAP_32K_TICKS_PER_SEC (32768)
/*
* TRM says 1 / HZ = ( TVR + 1) / 32768, so TRV = (32768 / HZ) - 1
* so with HZ = 128, TVR = 255.
*/
+#define OMAP_32K_TIMER_TICK_PERIOD ((32768 / HZ) - 1)
-#define OMAP_32K_TIMER_TICK_PERIOD ((OMAP_32K_TICKS_PER_SEC / HZ) - 1)
#define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate) \
(((nr_jiffies) * (clock_rate)) / HZ)
@@ -144,28 +142,6 @@
#endif
-static void omap_32k_timer_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
-{
- switch (mode) {
- case CLOCK_EVT_MODE_ONESHOT:
- case CLOCK_EVT_MODE_PERIODIC:
- omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
- break;
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- omap_32k_timer_stop();
- break;
- }
-}
-
-static struct clock_event_device clockevent_32k_timer = {
- .name = "32k-timer",
- .features = CLOCK_EVT_FEAT_PERIODIC,
- .shift = 32,
- .set_mode = omap_32k_timer_set_mode,
-};
-
/*
* The 32KHz synchronized timer is an additional timer on 16xx.
* It is always running.
@@ -195,6 +171,15 @@
static unsigned long omap_32k_last_tick = 0;
/*
+ * Returns elapsed usecs since last 32k timer interrupt
+ */
+static unsigned long omap_32k_timer_gettimeoffset(void)
+{
+ unsigned long now = omap_32k_sync_timer_read();
+ return omap_32k_ticks_to_usecs(now - omap_32k_last_tick);
+}
+
+/*
* Returns current time from boot in nsecs. It's OK for this to wrap
* around for now, as it's just a relative time stamp.
*/
@@ -203,16 +188,95 @@
return omap_32k_ticks_to_nsecs(omap_32k_sync_timer_read());
}
+/*
+ * Timer interrupt for 32KHz timer. When dynamic tick is enabled, this
+ * function is also called from other interrupts to remove latency
+ * issues with dynamic tick. In the dynamic tick case, we need to lock
+ * with irqsave.
+ */
+static inline irqreturn_t _omap_32k_timer_interrupt(int irq, void *dev_id)
+{
+ unsigned long now;
+
+ omap_32k_timer_ack_irq();
+ now = omap_32k_sync_timer_read();
+
+ while ((signed long)(now - omap_32k_last_tick)
+ >= OMAP_32K_TICKS_PER_HZ) {
+ omap_32k_last_tick += OMAP_32K_TICKS_PER_HZ;
+ timer_tick();
+ }
+
+ /* Restart timer so we don't drift off due to modulo or dynamic tick.
+ * By default we program the next timer to be continuous to avoid
+ * latencies during high system load. During dynamic tick operation the
+ * continuous timer can be overridden from pm_idle to be longer.
+ */
+ omap_32k_timer_start(omap_32k_last_tick + OMAP_32K_TICKS_PER_HZ - now);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t omap_32k_timer_handler(int irq, void *dev_id)
+{
+ return _omap_32k_timer_interrupt(irq, dev_id);
+}
+
static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id)
{
+ unsigned long flags;
- struct clock_event_device *evt = &clockevent_32k_timer;
- omap_32k_timer_ack_irq();
+ write_seqlock_irqsave(&xtime_lock, flags);
+ _omap_32k_timer_interrupt(irq, dev_id);
+ write_sequnlock_irqrestore(&xtime_lock, flags);
- evt->event_handler(evt);
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)
+{
+ unsigned long ticks = JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1;
+ unsigned long now = omap_32k_sync_timer_read();
+ unsigned long idled = now - omap_32k_last_tick;
+
+ if (idled + 1 < ticks)
+ ticks -= idled;
+ else
+ ticks = 1;
+ omap_32k_timer_start(ticks);
+}
+
+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_handler,
+};
+#endif /* CONFIG_NO_IDLE_HZ */
+
static struct irqaction omap_32k_timer_irq = {
.name = "32KHz timer",
.flags = IRQF_DISABLED | IRQF_TIMER,
@@ -221,8 +285,13 @@
static __init void omap_init_32k_timer(void)
{
+#ifdef CONFIG_NO_IDLE_HZ
+ omap_timer.dyn_tick = &omap_dyn_tick_timer;
+#endif
+
if (cpu_class_is_omap1())
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();
#ifdef CONFIG_ARCH_OMAP2
@@ -239,16 +308,7 @@
}
#endif
+ omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
- clockevent_32k_timer.mult = div_sc(OMAP_32K_TICKS_PER_SEC,
- NSEC_PER_SEC,
- clockevent_32k_timer.shift);
- clockevent_32k_timer.max_delta_ns =
- clockevent_delta2ns(0xfffffffe, &clockevent_32k_timer);
- clockevent_32k_timer.min_delta_ns =
- clockevent_delta2ns(1, &clockevent_32k_timer);
-
- clockevent_32k_timer.cpumask = cpumask_of_cpu(0);
- clockevents_register_device(&clockevent_32k_timer);
}
/*
@@ -266,4 +326,5 @@
struct sys_timer omap_timer = {
.init = omap_timer_init,
+ .offset = NULL, /* Initialized later */
};
--
-
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