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Diffstat (limited to 'drivers/clocksource/samsung_pwm_timer.c')
-rw-r--r--drivers/clocksource/samsung_pwm_timer.c108
1 files changed, 59 insertions, 49 deletions
diff --git a/drivers/clocksource/samsung_pwm_timer.c b/drivers/clocksource/samsung_pwm_timer.c
index 584b5472eea3..ac60f8b8a5f7 100644
--- a/drivers/clocksource/samsung_pwm_timer.c
+++ b/drivers/clocksource/samsung_pwm_timer.c
@@ -44,16 +44,28 @@
#define TCFG1_SHIFT(x) ((x) * 4)
#define TCFG1_MUX_MASK 0xf
+/*
+ * Each channel occupies 4 bits in TCON register, but there is a gap of 4
+ * bits (one channel) after channel 0, so channels have different numbering
+ * when accessing TCON register.
+ *
+ * In addition, the location of autoreload bit for channel 4 (TCON channel 5)
+ * in its set of bits is 2 as opposed to 3 for other channels.
+ */
#define TCON_START(chan) (1 << (4 * (chan) + 0))
#define TCON_MANUALUPDATE(chan) (1 << (4 * (chan) + 1))
#define TCON_INVERT(chan) (1 << (4 * (chan) + 2))
-#define TCON_AUTORELOAD(chan) (1 << (4 * (chan) + 3))
+#define _TCON_AUTORELOAD(chan) (1 << (4 * (chan) + 3))
+#define _TCON_AUTORELOAD4(chan) (1 << (4 * (chan) + 2))
+#define TCON_AUTORELOAD(chan) \
+ ((chan < 5) ? _TCON_AUTORELOAD(chan) : _TCON_AUTORELOAD4(chan))
DEFINE_SPINLOCK(samsung_pwm_lock);
EXPORT_SYMBOL(samsung_pwm_lock);
struct samsung_pwm_clocksource {
void __iomem *base;
+ void __iomem *source_reg;
unsigned int irq[SAMSUNG_PWM_NUM];
struct samsung_pwm_variant variant;
@@ -195,17 +207,6 @@ static int samsung_set_next_event(unsigned long cycles,
return 0;
}
-static void samsung_timer_resume(void)
-{
- /* event timer restart */
- samsung_time_setup(pwm.event_id, pwm.clock_count_per_tick - 1);
- samsung_time_start(pwm.event_id, true);
-
- /* source timer restart */
- samsung_time_setup(pwm.source_id, pwm.tcnt_max);
- samsung_time_start(pwm.source_id, true);
-}
-
static void samsung_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
@@ -222,20 +223,29 @@ static void samsung_set_mode(enum clock_event_mode mode,
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
- break;
-
case CLOCK_EVT_MODE_RESUME:
- samsung_timer_resume();
break;
}
}
+static void samsung_clockevent_resume(struct clock_event_device *cev)
+{
+ samsung_timer_set_prescale(pwm.event_id, pwm.tscaler_div);
+ samsung_timer_set_divisor(pwm.event_id, pwm.tdiv);
+
+ if (pwm.variant.has_tint_cstat) {
+ u32 mask = (1 << pwm.event_id);
+ writel(mask | (mask << 5), pwm.base + REG_TINT_CSTAT);
+ }
+}
+
static struct clock_event_device time_event_device = {
.name = "samsung_event_timer",
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
.rating = 200,
.set_next_event = samsung_set_next_event,
.set_mode = samsung_set_mode,
+ .resume = samsung_clockevent_resume,
};
static irqreturn_t samsung_clock_event_isr(int irq, void *dev_id)
@@ -286,23 +296,34 @@ static void __init samsung_clockevent_init(void)
}
}
-static void __iomem *samsung_timer_reg(void)
+static void samsung_clocksource_suspend(struct clocksource *cs)
{
- switch (pwm.source_id) {
- case 0:
- case 1:
- case 2:
- case 3:
- return pwm.base + pwm.source_id * 0x0c + 0x14;
-
- case 4:
- return pwm.base + 0x40;
-
- default:
- BUG();
- }
+ samsung_time_stop(pwm.source_id);
}
+static void samsung_clocksource_resume(struct clocksource *cs)
+{
+ samsung_timer_set_prescale(pwm.source_id, pwm.tscaler_div);
+ samsung_timer_set_divisor(pwm.source_id, pwm.tdiv);
+
+ samsung_time_setup(pwm.source_id, pwm.tcnt_max);
+ samsung_time_start(pwm.source_id, true);
+}
+
+static cycle_t samsung_clocksource_read(struct clocksource *c)
+{
+ return ~readl_relaxed(pwm.source_reg);
+}
+
+static struct clocksource samsung_clocksource = {
+ .name = "samsung_clocksource_timer",
+ .rating = 250,
+ .read = samsung_clocksource_read,
+ .suspend = samsung_clocksource_suspend,
+ .resume = samsung_clocksource_resume,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
/*
* Override the global weak sched_clock symbol with this
* local implementation which uses the clocksource to get some
@@ -312,17 +333,11 @@ static void __iomem *samsung_timer_reg(void)
*/
static u32 notrace samsung_read_sched_clock(void)
{
- void __iomem *reg = samsung_timer_reg();
-
- if (!reg)
- return 0;
-
- return ~__raw_readl(reg);
+ return samsung_clocksource_read(NULL);
}
static void __init samsung_clocksource_init(void)
{
- void __iomem *reg = samsung_timer_reg();
unsigned long pclk;
unsigned long clock_rate;
int ret;
@@ -337,12 +352,16 @@ static void __init samsung_clocksource_init(void)
samsung_time_setup(pwm.source_id, pwm.tcnt_max);
samsung_time_start(pwm.source_id, true);
+ if (pwm.source_id == 4)
+ pwm.source_reg = pwm.base + 0x40;
+ else
+ pwm.source_reg = pwm.base + pwm.source_id * 0x0c + 0x14;
+
setup_sched_clock(samsung_read_sched_clock,
pwm.variant.bits, clock_rate);
- ret = clocksource_mmio_init(reg, "samsung_clocksource_timer",
- clock_rate, 250, pwm.variant.bits,
- clocksource_mmio_readl_down);
+ samsung_clocksource.mask = CLOCKSOURCE_MASK(pwm.variant.bits);
+ ret = clocksource_register_hz(&samsung_clocksource, clock_rate);
if (ret)
panic("samsung_clocksource_timer: can't register clocksource\n");
}
@@ -404,7 +423,6 @@ void __init samsung_pwm_clocksource_init(void __iomem *base,
static void __init samsung_pwm_alloc(struct device_node *np,
const struct samsung_pwm_variant *variant)
{
- struct resource res;
struct property *prop;
const __be32 *cur;
u32 val;
@@ -423,17 +441,9 @@ static void __init samsung_pwm_alloc(struct device_node *np,
pwm.variant.output_mask |= 1 << val;
}
- of_address_to_resource(np, 0, &res);
- if (!request_mem_region(res.start,
- resource_size(&res), "samsung-pwm")) {
- pr_err("%s: failed to request IO mem region\n", __func__);
- return;
- }
-
- pwm.base = ioremap(res.start, resource_size(&res));
+ pwm.base = of_iomap(np, 0);
if (!pwm.base) {
pr_err("%s: failed to map PWM registers\n", __func__);
- release_mem_region(res.start, resource_size(&res));
return;
}