ARM: gemini: Use timer1 for clockevent

Use timer1 as clockevent timer.
The old driver uses timer2, which has some issues to setup

Signed-off-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

diff --git a/arch/arm/mach-gemini/time.c b/arch/arm/mach-gemini/time.c
index fd751b14118224e876b5220066b584e3681c7c5e..5e2b1bab446260c6aea3a3ecbc2233c7c856a25a 100644 (file)
--- a/arch/arm/mach-gemini/time.c
+++ b/arch/arm/mach-gemini/time.c
@@ -67,19 +67,11 @@ static int gemini_timer_set_next_event(unsigned long cycles,
 {
        u32 cr;
 
-       cr = readl(TIMER_CR);
-
-       /* This may be overdoing it, feel free to test without this */
-       cr &= ~TIMER_2_CR_ENABLE;
-       cr &= ~TIMER_2_CR_INT;
-       writel(cr, TIMER_CR);
-
-       /* Set next event */
-       writel(cycles, TIMER_COUNT(TIMER2_BASE));
-       writel(cycles, TIMER_LOAD(TIMER2_BASE));
-       cr |= TIMER_2_CR_ENABLE;
-       cr |= TIMER_2_CR_INT;
-       writel(cr, TIMER_CR);
+       /* Setup the match register */
+       cr = readl(TIMER_COUNT(TIMER1_BASE));
+       writel(cr + cycles, TIMER_MATCH1(TIMER1_BASE));
+       if (readl(TIMER_COUNT(TIMER1_BASE)) - cr > cycles)
+               return -ETIME;
 
        return 0;
 }
@@ -92,10 +84,26 @@ static int gemini_timer_shutdown(struct clock_event_device *evt)
         * Disable also for oneshot: the set_next() call will arm the timer
         * instead.
         */
+       /* Stop timer and interrupt. */
        cr = readl(TIMER_CR);
-       cr &= ~TIMER_2_CR_ENABLE;
-       cr &= ~TIMER_2_CR_INT;
+       cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
        writel(cr, TIMER_CR);
+
+       /* Setup counter start from 0 */
+       writel(0, TIMER_COUNT(TIMER1_BASE));
+       writel(0, TIMER_LOAD(TIMER1_BASE));
+
+       /* enable interrupt */
+       cr = readl(TIMER_INTR_MASK);
+       cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
+       cr |= TIMER_1_INT_MATCH1;
+       writel(cr, TIMER_INTR_MASK);
+
+       /* start the timer */
+       cr = readl(TIMER_CR);
+       cr |= TIMER_1_CR_ENABLE;
+       writel(cr, TIMER_CR);
+
        return 0;
 }
 
@@ -104,21 +112,37 @@ static int gemini_timer_set_periodic(struct clock_event_device *evt)
        u32 period = DIV_ROUND_CLOSEST(tick_rate, HZ);
        u32 cr;
 
+       /* Stop timer and interrupt */
+       cr = readl(TIMER_CR);
+       cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
+       writel(cr, TIMER_CR);
+
+       /* Setup timer to fire at 1/HT intervals. */
+       cr = 0xffffffff - (period - 1);
+       writel(cr, TIMER_COUNT(TIMER1_BASE));
+       writel(cr, TIMER_LOAD(TIMER1_BASE));
+
+       /* enable interrupt on overflow */
+       cr = readl(TIMER_INTR_MASK);
+       cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
+       cr |= TIMER_1_INT_OVERFLOW;
+       writel(cr, TIMER_INTR_MASK);
+
        /* Start the timer */
-       writel(period, TIMER_COUNT(TIMER2_BASE));
-       writel(period, TIMER_LOAD(TIMER2_BASE));
        cr = readl(TIMER_CR);
-       cr |= TIMER_2_CR_ENABLE;
-       cr |= TIMER_2_CR_INT;
+       cr |= TIMER_1_CR_ENABLE;
+       cr |= TIMER_1_CR_INT;
        writel(cr, TIMER_CR);
+
        return 0;
 }
 
-/* Use TIMER2 as clock event */
+/* Use TIMER1 as clock event */
 static struct clock_event_device gemini_clockevent = {
-       .name                   = "TIMER2",
+       .name                   = "TIMER1",
        /* Reasonably fast and accurate clock event */
        .rating                 = 300,
+       .shift                  = 32,
        .features               = CLOCK_EVT_FEAT_PERIODIC |
                                  CLOCK_EVT_FEAT_ONESHOT,
        .set_next_event         = gemini_timer_set_next_event,
@@ -175,20 +199,22 @@ void __init gemini_timer_init(void)
        }
 
        /*
-        * Make irqs happen for the system timer
+        * Reset the interrupt mask and status
         */
-       setup_irq(IRQ_TIMER2, &gemini_timer_irq);
-
-       /* Enable and use TIMER1 as clock source */
-       writel(0xffffffff, TIMER_COUNT(TIMER1_BASE));
-       writel(0xffffffff, TIMER_LOAD(TIMER1_BASE));
-       writel(TIMER_1_CR_ENABLE, TIMER_CR);
-       if (clocksource_mmio_init(TIMER_COUNT(TIMER1_BASE),
-                                 "TIMER1", tick_rate, 300, 32,
-                                 clocksource_mmio_readl_up))
-               pr_err("timer: failed to initialize gemini clock source\n");
-
-       /* Configure and register the clockevent */
+       writel(TIMER_INT_ALL_MASK, TIMER_INTR_MASK);
+       writel(0, TIMER_INTR_STATE);
+       writel(TIMER_DEFAULT_FLAGS, TIMER_CR);
+
+       /*
+        * Setup clockevent timer (interrupt-driven.)
+        */
+       writel(0, TIMER_COUNT(TIMER1_BASE));
+       writel(0, TIMER_LOAD(TIMER1_BASE));
+       writel(0, TIMER_MATCH1(TIMER1_BASE));
+       writel(0, TIMER_MATCH2(TIMER1_BASE));
+       setup_irq(IRQ_TIMER1, &gemini_timer_irq);
+       gemini_clockevent.cpumask = cpumask_of(0);
        clockevents_config_and_register(&gemini_clockevent, tick_rate,
                                        1, 0xffffffff);
+
 }