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path: root/drivers/clocksource/timer-fttmr010.c
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Diffstat (limited to 'drivers/clocksource/timer-fttmr010.c')
-rw-r--r--drivers/clocksource/timer-fttmr010.c143
1 files changed, 106 insertions, 37 deletions
diff --git a/drivers/clocksource/timer-fttmr010.c b/drivers/clocksource/timer-fttmr010.c
index 2d915d1455ab..f8801507a687 100644
--- a/drivers/clocksource/timer-fttmr010.c
+++ b/drivers/clocksource/timer-fttmr010.c
@@ -50,6 +50,20 @@
#define TIMER_2_CR_UPDOWN BIT(10)
#define TIMER_3_CR_UPDOWN BIT(11)
+/*
+ * The Aspeed AST2400 moves bits around in the control register
+ * and lacks bits for setting the timer to count upwards.
+ */
+#define TIMER_1_CR_ASPEED_ENABLE BIT(0)
+#define TIMER_1_CR_ASPEED_CLOCK BIT(1)
+#define TIMER_1_CR_ASPEED_INT BIT(2)
+#define TIMER_2_CR_ASPEED_ENABLE BIT(4)
+#define TIMER_2_CR_ASPEED_CLOCK BIT(5)
+#define TIMER_2_CR_ASPEED_INT BIT(6)
+#define TIMER_3_CR_ASPEED_ENABLE BIT(8)
+#define TIMER_3_CR_ASPEED_CLOCK BIT(9)
+#define TIMER_3_CR_ASPEED_INT BIT(10)
+
#define TIMER_1_INT_MATCH1 BIT(0)
#define TIMER_1_INT_MATCH2 BIT(1)
#define TIMER_1_INT_OVERFLOW BIT(2)
@@ -64,6 +78,8 @@
struct fttmr010 {
void __iomem *base;
unsigned int tick_rate;
+ bool count_down;
+ u32 t1_enable_val;
struct clock_event_device clkevt;
};
@@ -77,6 +93,8 @@ static inline struct fttmr010 *to_fttmr010(struct clock_event_device *evt)
static u64 notrace fttmr010_read_sched_clock(void)
{
+ if (local_fttmr->count_down)
+ return ~readl(local_fttmr->base + TIMER2_COUNT);
return readl(local_fttmr->base + TIMER2_COUNT);
}
@@ -86,11 +104,23 @@ static int fttmr010_timer_set_next_event(unsigned long cycles,
struct fttmr010 *fttmr010 = to_fttmr010(evt);
u32 cr;
- /* Setup the match register */
+ /* Stop */
+ cr = readl(fttmr010->base + TIMER_CR);
+ cr &= ~fttmr010->t1_enable_val;
+ writel(cr, fttmr010->base + TIMER_CR);
+
+ /* Setup the match register forward/backward in time */
cr = readl(fttmr010->base + TIMER1_COUNT);
- writel(cr + cycles, fttmr010->base + TIMER1_MATCH1);
- if (readl(fttmr010->base + TIMER1_COUNT) - cr > cycles)
- return -ETIME;
+ if (fttmr010->count_down)
+ cr -= cycles;
+ else
+ cr += cycles;
+ writel(cr, fttmr010->base + TIMER1_MATCH1);
+
+ /* Start */
+ cr = readl(fttmr010->base + TIMER_CR);
+ cr |= fttmr010->t1_enable_val;
+ writel(cr, fttmr010->base + TIMER_CR);
return 0;
}
@@ -100,9 +130,9 @@ static int fttmr010_timer_shutdown(struct clock_event_device *evt)
struct fttmr010 *fttmr010 = to_fttmr010(evt);
u32 cr;
- /* Stop timer and interrupt. */
+ /* Stop */
cr = readl(fttmr010->base + TIMER_CR);
- cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
+ cr &= ~fttmr010->t1_enable_val;
writel(cr, fttmr010->base + TIMER_CR);
return 0;
@@ -113,14 +143,17 @@ static int fttmr010_timer_set_oneshot(struct clock_event_device *evt)
struct fttmr010 *fttmr010 = to_fttmr010(evt);
u32 cr;
- /* Stop timer and interrupt. */
+ /* Stop */
cr = readl(fttmr010->base + TIMER_CR);
- cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
+ cr &= ~fttmr010->t1_enable_val;
writel(cr, fttmr010->base + TIMER_CR);
- /* Setup counter start from 0 */
+ /* Setup counter start from 0 or ~0 */
writel(0, fttmr010->base + TIMER1_COUNT);
- writel(0, fttmr010->base + TIMER1_LOAD);
+ if (fttmr010->count_down)
+ writel(~0, fttmr010->base + TIMER1_LOAD);
+ else
+ writel(0, fttmr010->base + TIMER1_LOAD);
/* Enable interrupt */
cr = readl(fttmr010->base + TIMER_INTR_MASK);
@@ -128,11 +161,6 @@ static int fttmr010_timer_set_oneshot(struct clock_event_device *evt)
cr |= TIMER_1_INT_MATCH1;
writel(cr, fttmr010->base + TIMER_INTR_MASK);
- /* Start the timer */
- cr = readl(fttmr010->base + TIMER_CR);
- cr |= TIMER_1_CR_ENABLE;
- writel(cr, fttmr010->base + TIMER_CR);
-
return 0;
}
@@ -142,26 +170,30 @@ static int fttmr010_timer_set_periodic(struct clock_event_device *evt)
u32 period = DIV_ROUND_CLOSEST(fttmr010->tick_rate, HZ);
u32 cr;
- /* Stop timer and interrupt */
+ /* Stop */
cr = readl(fttmr010->base + TIMER_CR);
- cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
+ cr &= ~fttmr010->t1_enable_val;
writel(cr, fttmr010->base + TIMER_CR);
- /* Setup timer to fire at 1/HT intervals. */
- cr = 0xffffffff - (period - 1);
- writel(cr, fttmr010->base + TIMER1_COUNT);
- writel(cr, fttmr010->base + TIMER1_LOAD);
-
- /* enable interrupt on overflow */
- cr = readl(fttmr010->base + TIMER_INTR_MASK);
- cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
- cr |= TIMER_1_INT_OVERFLOW;
- writel(cr, fttmr010->base + TIMER_INTR_MASK);
+ /* Setup timer to fire at 1/HZ intervals. */
+ if (fttmr010->count_down) {
+ writel(period, fttmr010->base + TIMER1_LOAD);
+ writel(0, fttmr010->base + TIMER1_MATCH1);
+ } else {
+ cr = 0xffffffff - (period - 1);
+ writel(cr, fttmr010->base + TIMER1_COUNT);
+ writel(cr, fttmr010->base + TIMER1_LOAD);
+
+ /* Enable interrupt on overflow */
+ cr = readl(fttmr010->base + TIMER_INTR_MASK);
+ cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
+ cr |= TIMER_1_INT_OVERFLOW;
+ writel(cr, fttmr010->base + TIMER_INTR_MASK);
+ }
/* Start the timer */
cr = readl(fttmr010->base + TIMER_CR);
- cr |= TIMER_1_CR_ENABLE;
- cr |= TIMER_1_CR_INT;
+ cr |= fttmr010->t1_enable_val;
writel(cr, fttmr010->base + TIMER_CR);
return 0;
@@ -181,9 +213,11 @@ static irqreturn_t fttmr010_timer_interrupt(int irq, void *dev_id)
static int __init fttmr010_timer_init(struct device_node *np)
{
struct fttmr010 *fttmr010;
+ bool is_ast2400;
int irq;
struct clk *clk;
int ret;
+ u32 val;
/*
* These implementations require a clock reference.
@@ -223,13 +257,37 @@ static int __init fttmr010_timer_init(struct device_node *np)
}
/*
+ * The Aspeed AST2400 moves bits around in the control register,
+ * otherwise it works the same.
+ */
+ is_ast2400 = of_device_is_compatible(np, "aspeed,ast2400-timer");
+ if (is_ast2400) {
+ fttmr010->t1_enable_val = TIMER_1_CR_ASPEED_ENABLE |
+ TIMER_1_CR_ASPEED_INT;
+ /* Downward not available */
+ fttmr010->count_down = true;
+ } else {
+ fttmr010->t1_enable_val = TIMER_1_CR_ENABLE | TIMER_1_CR_INT;
+ }
+
+ /*
* Reset the interrupt mask and status
*/
writel(TIMER_INT_ALL_MASK, fttmr010->base + TIMER_INTR_MASK);
writel(0, fttmr010->base + TIMER_INTR_STATE);
- /* Enable timer 1 count up, timer 2 count up */
- writel((TIMER_1_CR_UPDOWN | TIMER_2_CR_ENABLE | TIMER_2_CR_UPDOWN),
- fttmr010->base + TIMER_CR);
+
+ /*
+ * Enable timer 1 count up, timer 2 count up, except on Aspeed,
+ * where everything just counts down.
+ */
+ if (is_ast2400)
+ val = TIMER_2_CR_ASPEED_ENABLE;
+ else {
+ val = TIMER_2_CR_ENABLE;
+ if (!fttmr010->count_down)
+ val |= TIMER_1_CR_UPDOWN | TIMER_2_CR_UPDOWN;
+ }
+ writel(val, fttmr010->base + TIMER_CR);
/*
* Setup free-running clocksource timer (interrupts
@@ -237,13 +295,22 @@ static int __init fttmr010_timer_init(struct device_node *np)
*/
local_fttmr = fttmr010;
writel(0, fttmr010->base + TIMER2_COUNT);
- writel(0, fttmr010->base + TIMER2_LOAD);
writel(0, fttmr010->base + TIMER2_MATCH1);
writel(0, fttmr010->base + TIMER2_MATCH2);
- clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
- "FTTMR010-TIMER2",
- fttmr010->tick_rate,
- 300, 32, clocksource_mmio_readl_up);
+
+ if (fttmr010->count_down) {
+ writel(~0, fttmr010->base + TIMER2_LOAD);
+ clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
+ "FTTMR010-TIMER2",
+ fttmr010->tick_rate,
+ 300, 32, clocksource_mmio_readl_down);
+ } else {
+ writel(0, fttmr010->base + TIMER2_LOAD);
+ clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
+ "FTTMR010-TIMER2",
+ fttmr010->tick_rate,
+ 300, 32, clocksource_mmio_readl_up);
+ }
sched_clock_register(fttmr010_read_sched_clock, 32,
fttmr010->tick_rate);
@@ -290,3 +357,5 @@ out_disable_clock:
}
CLOCKSOURCE_OF_DECLARE(fttmr010, "faraday,fttmr010", fttmr010_timer_init);
CLOCKSOURCE_OF_DECLARE(gemini, "cortina,gemini-timer", fttmr010_timer_init);
+CLOCKSOURCE_OF_DECLARE(moxart, "moxa,moxart-timer", fttmr010_timer_init);
+CLOCKSOURCE_OF_DECLARE(aspeed, "aspeed,ast2400-timer", fttmr010_timer_init);