[PATCH linux dev-5.3 4/4] clocksource: fttmr010: Add support for ast2600

[Joel Stanley]

The ast2600 has some minor differences to previous versions. The
interrupt handler must acknowledge the timer interrupt in a status
register. Secondly the control register becomes write to set only,
requiring the use of a separate set to clear register.

Signed-off-by: Joel Stanley <joel at jms.id.au>
---
 drivers/clocksource/timer-fttmr010.c | 34 ++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/clocksource/timer-fttmr010.c b/drivers/clocksource/timer-fttmr010.c
index 8a79025339d0..688d540ebddd 100644
--- a/drivers/clocksource/timer-fttmr010.c
+++ b/drivers/clocksource/timer-fttmr010.c
@@ -37,6 +37,11 @@
 #define TIMER3_MATCH2		(0x2c)
 #define TIMER_CR		(0x30)
 
+/*
+  Control register set to clear for ast2600 only.
+ */
+#define TIMER_CR_CLR		(0x3c)
+
 /*
  * Control register (TMC30) bit fields for fttmr010/gemini/moxart timers.
  */
@@ -163,6 +168,16 @@ static int fttmr010_timer_set_next_event(unsigned long cycles,
 	return 0;
 }
 
+static int ast2600_timer_shutdown(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+
+	/* Stop */
+	writel(fttmr010->t1_enable_val, fttmr010->base + TIMER_CR_CLR);
+
+	return 0;
+}
+
 static int fttmr010_timer_shutdown(struct clock_event_device *evt)
 {
 	struct fttmr010 *fttmr010 = to_fttmr010(evt);
@@ -244,6 +259,17 @@ static irqreturn_t fttmr010_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t ast2600_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+
+	writel(0x1, fttmr010->base + TIMER_INTR_STATE);
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
 static int __init fttmr010_common_init(struct device_node *np,
 		bool is_aspeed,
 		int (*timer_shutdown)(struct clock_event_device *),
@@ -404,6 +430,13 @@ static int __init fttmr010_common_init(struct device_node *np,
 	return ret;
 }
 
+static __init int ast2600_timer_init(struct device_node *np)
+{
+	return fttmr010_common_init(np, true,
+			ast2600_timer_shutdown,
+			ast2600_timer_interrupt);
+}
+
 static __init int aspeed_timer_init(struct device_node *np)
 {
 	return fttmr010_common_init(np, true,
@@ -423,3 +456,4 @@ TIMER_OF_DECLARE(gemini, "cortina,gemini-timer", fttmr010_timer_init);
 TIMER_OF_DECLARE(moxart, "moxa,moxart-timer", fttmr010_timer_init);
 TIMER_OF_DECLARE(ast2400, "aspeed,ast2400-timer", aspeed_timer_init);
 TIMER_OF_DECLARE(ast2500, "aspeed,ast2500-timer", aspeed_timer_init);
+TIMER_OF_DECLARE(ast2600, "aspeed,ast2600-timer", ast2600_timer_init);
-- 
2.24.0.rc1