[PATCH 5/8] msm: timer: Remove msm_clocks[] and simplify code

From: Stephen Boyd
Date: Tue Nov 08 2011 - 13:36:03 EST


We can simplify the timer code now that we only use the DGT for
the clocksource and the GPT for the clockevent. Get rid of the
msm_clocks[] array and propagate the changes throughout the code.
This reduces the lines of code in this file and improves
readability.

Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
---
arch/arm/mach-msm/timer.c | 221 ++++++++++++++++-----------------------------
1 files changed, 76 insertions(+), 145 deletions(-)

diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
index 9f3671a..fc06464 100644
--- a/arch/arm/mach-msm/timer.c
+++ b/arch/arm/mach-msm/timer.c
@@ -40,8 +40,6 @@

#define GPT_HZ 32768

-#define MSM_GLOBAL_TIMER MSM_CLOCK_GPT
-
/* TODO: Remove these ifdefs */
#if defined(CONFIG_ARCH_QSD8X50)
#define DGT_HZ (19200000 / 4) /* 19.2 MHz / 4 by default */
@@ -57,31 +55,7 @@
#define MSM_DGT_SHIFT (5)
#endif

-struct msm_clock {
- struct clock_event_device clockevent;
- struct clocksource clocksource;
- unsigned int irq;
- void __iomem *regbase;
- uint32_t freq;
- uint32_t shift;
- void __iomem *global_counter;
- void __iomem *local_counter;
- union {
- struct clock_event_device *evt;
- struct clock_event_device __percpu **percpu_evt;
- };
-};
-
-enum {
- MSM_CLOCK_GPT,
- MSM_CLOCK_DGT,
- NR_TIMERS,
-};
-
-
-static struct msm_clock msm_clocks[];
-
-static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt);
+static void __iomem *event_base;

static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
{
@@ -90,59 +64,31 @@ static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
/* Stop the timer tick */
if (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
- struct msm_clock *clock = clockevent_to_clock(evt);
- u32 ctrl = readl_relaxed(clock->regbase + TIMER_ENABLE);
+ u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~TIMER_ENABLE_EN;
- writel_relaxed(ctrl, clock->regbase + TIMER_ENABLE);
+ writel_relaxed(ctrl, event_base + TIMER_ENABLE);
}
evt->event_handler(evt);
return IRQ_HANDLED;
}

-static cycle_t msm_read_timer_count(struct clocksource *cs)
-{
- struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource);
-
- /*
- * Shift timer count down by a constant due to unreliable lower bits
- * on some targets.
- */
- return readl(clk->global_counter) >> clk->shift;
-}
-
-static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt)
-{
-#ifdef CONFIG_SMP
- int i;
- for (i = 0; i < NR_TIMERS; i++)
- if (evt == &(msm_clocks[i].clockevent))
- return &msm_clocks[i];
- return &msm_clocks[MSM_GLOBAL_TIMER];
-#else
- return container_of(evt, struct msm_clock, clockevent);
-#endif
-}
-
static int msm_timer_set_next_event(unsigned long cycles,
struct clock_event_device *evt)
{
- struct msm_clock *clock = clockevent_to_clock(evt);
- u32 match = cycles << clock->shift;
- u32 ctrl = readl_relaxed(clock->regbase + TIMER_ENABLE);
+ u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);

- writel_relaxed(0, clock->regbase + TIMER_CLEAR);
- writel_relaxed(match, clock->regbase + TIMER_MATCH_VAL);
- writel_relaxed(ctrl | TIMER_ENABLE_EN, clock->regbase + TIMER_ENABLE);
+ writel_relaxed(0, event_base + TIMER_CLEAR);
+ writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
+ writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
return 0;
}

static void msm_timer_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
- struct msm_clock *clock = clockevent_to_clock(evt);
u32 ctrl;

- ctrl = readl_relaxed(clock->regbase + TIMER_ENABLE);
+ ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);

switch (mode) {
@@ -156,59 +102,61 @@ static void msm_timer_set_mode(enum clock_event_mode mode,
case CLOCK_EVT_MODE_SHUTDOWN:
break;
}
- writel_relaxed(ctrl, clock->regbase + TIMER_ENABLE);
+ writel_relaxed(ctrl, event_base + TIMER_ENABLE);
}

-static struct msm_clock msm_clocks[] = {
- [MSM_CLOCK_GPT] = {
- .clockevent = {
- .name = "gp_timer",
- .features = CLOCK_EVT_FEAT_ONESHOT,
- .shift = 32,
- .rating = 200,
- .set_next_event = msm_timer_set_next_event,
- .set_mode = msm_timer_set_mode,
- },
- .irq = INT_GP_TIMER_EXP,
- .freq = GPT_HZ,
- },
- [MSM_CLOCK_DGT] = {
- .clocksource = {
- .name = "dg_timer",
- .rating = 300,
- .read = msm_read_timer_count,
- .mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)),
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
- },
- .freq = DGT_HZ >> MSM_DGT_SHIFT,
- .shift = MSM_DGT_SHIFT,
- }
+static struct clock_event_device msm_clockevent = {
+ .name = "gp_timer",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .shift = 32,
+ .rating = 200,
+ .set_next_event = msm_timer_set_next_event,
+ .set_mode = msm_timer_set_mode,
+};
+
+static union {
+ struct clock_event_device *evt;
+ struct clock_event_device __percpu **percpu_evt;
+} msm_evt;
+
+static void __iomem *source_base;
+
+static cycle_t msm_read_timer_count(struct clocksource *cs)
+{
+ /*
+ * Shift timer count down by a constant due to unreliable lower bits
+ * on some targets.
+ */
+ return readl_relaxed(source_base + TIMER_COUNT_VAL) >> MSM_DGT_SHIFT;
+}
+
+static struct clocksource msm_clocksource = {
+ .name = "dg_timer",
+ .rating = 300,
+ .read = msm_read_timer_count,
+ .mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

static void __init msm_timer_init(void)
{
- struct msm_clock *clock;
- struct clock_event_device *ce = &msm_clocks[MSM_CLOCK_GPT].clockevent;
- struct clocksource *cs = &msm_clocks[MSM_CLOCK_DGT].clocksource;
+ struct clock_event_device *ce = &msm_clockevent;
+ struct clocksource *cs = &msm_clocksource;
int res;
- int global_offset = 0;
-

if (cpu_is_msm7x01()) {
- msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE;
- msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10;
+ event_base = MSM_CSR_BASE;
+ source_base = MSM_CSR_BASE + 0x10;
} else if (cpu_is_msm7x30()) {
- msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE + 0x04;
- msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x24;
+ event_base = MSM_CSR_BASE + 0x04;
+ source_base = MSM_CSR_BASE + 0x24;
} else if (cpu_is_qsd8x50()) {
- msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE;
- msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10;
+ event_base = MSM_CSR_BASE;
+ source_base = MSM_CSR_BASE + 0x10;
} else if (cpu_is_msm8x60() || cpu_is_msm8960()) {
- msm_clocks[MSM_CLOCK_GPT].regbase = MSM_TMR_BASE + 0x04;
- msm_clocks[MSM_CLOCK_DGT].regbase = MSM_TMR_BASE + 0x24;
-
- /* Use CPU0's timer as the global timer. */
- global_offset = MSM_TMR0_BASE - MSM_TMR_BASE;
+ event_base = MSM_TMR_BASE + 0x04;
+ /* Use CPU0's timer as the global clock source. */
+ source_base = MSM_TMR0_BASE + 0x24;
} else
BUG();

@@ -216,88 +164,71 @@ static void __init msm_timer_init(void)
writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
#endif

- clock = &msm_clocks[MSM_CLOCK_GPT];
- clock->local_counter = clock->regbase + TIMER_COUNT_VAL;
-
- writel_relaxed(0, clock->regbase + TIMER_ENABLE);
- writel_relaxed(0, clock->regbase + TIMER_CLEAR);
- writel_relaxed(~0, clock->regbase + TIMER_MATCH_VAL);
- ce->mult = div_sc(clock->freq, NSEC_PER_SEC, ce->shift);
+ writel_relaxed(0, event_base + TIMER_ENABLE);
+ writel_relaxed(0, event_base + TIMER_CLEAR);
+ writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
+ ce->mult = div_sc(GPT_HZ, NSEC_PER_SEC, ce->shift);
/*
* allow at least 10 seconds to notice that the timer
* wrapped
*/
- ce->max_delta_ns =
- clockevent_delta2ns(0xf0000000 >> clock->shift, ce);
+ ce->max_delta_ns = clockevent_delta2ns(0xf0000000, ce);
/* 4 gets rounded down to 3 */
ce->min_delta_ns = clockevent_delta2ns(4, ce);
ce->cpumask = cpumask_of(0);

- ce->irq = clock->irq;
+ ce->irq = INT_GP_TIMER_EXP;
if (cpu_is_msm8x60() || cpu_is_msm8960()) {
- clock->percpu_evt = alloc_percpu(struct clock_event_device *);
- if (!clock->percpu_evt) {
+ msm_evt.percpu_evt = alloc_percpu(struct clock_event_device *);
+ if (!msm_evt.percpu_evt) {
pr_err("memory allocation failed for %s\n", ce->name);
goto err;
}
-
- *__this_cpu_ptr(clock->percpu_evt) = ce;
+ *__this_cpu_ptr(msm_evt.percpu_evt) = ce;
res = request_percpu_irq(ce->irq, msm_timer_interrupt,
- ce->name, clock->percpu_evt);
+ ce->name, msm_evt.percpu_evt);
if (!res)
enable_percpu_irq(ce->irq, 0);
} else {
- clock->evt = ce;
+ msm_evt.evt = ce;
res = request_irq(ce->irq, msm_timer_interrupt,
IRQF_TIMER | IRQF_NOBALANCING |
- IRQF_TRIGGER_RISING, ce->name, &clock->evt);
+ IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt);
}

if (res)
pr_err("request_irq failed for %s\n", ce->name);
-
clockevents_register_device(ce);
err:
- clock = &msm_clocks[MSM_CLOCK_DGT];
- clock->local_counter = clock->regbase + TIMER_COUNT_VAL;
- clock->global_counter = clock->local_counter + global_offset;
- writel_relaxed(TIMER_ENABLE_EN, clock->regbase + TIMER_ENABLE);
- res = clocksource_register_hz(cs, clock->freq);
+ writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
+ res = clocksource_register_hz(cs, DGT_HZ >> MSM_DGT_SHIFT);
if (res)
- pr_err("clocksource_register failed for %s\n", cs->name);
+ pr_err("clocksource_register failed\n");
}

#ifdef CONFIG_LOCAL_TIMERS
int __cpuinit local_timer_setup(struct clock_event_device *evt)
{
- static bool local_timer_inited;
- struct msm_clock *clock = &msm_clocks[MSM_GLOBAL_TIMER];
-
/* Use existing clock_event for cpu 0 */
if (!smp_processor_id())
return 0;

- if (!local_timer_inited) {
- writel(0, clock->regbase + TIMER_ENABLE);
- writel(0, clock->regbase + TIMER_CLEAR);
- writel(~0, clock->regbase + TIMER_MATCH_VAL);
- local_timer_inited = true;
- }
- evt->irq = clock->irq;
+ writel_relaxed(0, event_base + TIMER_ENABLE);
+ writel_relaxed(0, event_base + TIMER_CLEAR);
+ writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
+ evt->irq = msm_clockevent.irq;
evt->name = "local_timer";
- evt->features = CLOCK_EVT_FEAT_ONESHOT;
- evt->rating = clock->clockevent.rating;
+ evt->features = msm_clockevent.features;
+ evt->rating = msm_clockevent.rating;
evt->set_mode = msm_timer_set_mode;
evt->set_next_event = msm_timer_set_next_event;
- evt->shift = clock->clockevent.shift;
- evt->mult = div_sc(clock->freq, NSEC_PER_SEC, evt->shift);
- evt->max_delta_ns =
- clockevent_delta2ns(0xf0000000 >> clock->shift, evt);
+ evt->shift = msm_clockevent.shift;
+ evt->mult = div_sc(GPT_HZ, NSEC_PER_SEC, evt->shift);
+ evt->max_delta_ns = clockevent_delta2ns(0xf0000000, evt);
evt->min_delta_ns = clockevent_delta2ns(4, evt);

- *__this_cpu_ptr(clock->percpu_evt) = evt;
+ *__this_cpu_ptr(msm_evt.percpu_evt) = evt;
enable_percpu_irq(evt->irq, 0);
-
clockevents_register_device(evt);
return 0;
}
--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

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