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Diffstat (limited to 'arch/arm/plat-nomadik/timer.c')
-rw-r--r--arch/arm/plat-nomadik/timer.c33
1 files changed, 12 insertions, 21 deletions
diff --git a/arch/arm/plat-nomadik/timer.c b/arch/arm/plat-nomadik/timer.c
index ea3ca86c5283..aedf9c1d645e 100644
--- a/arch/arm/plat-nomadik/timer.c
+++ b/arch/arm/plat-nomadik/timer.c
@@ -1,5 +1,5 @@
/*
- * linux/arch/arm/mach-nomadik/timer.c
+ * linux/arch/arm/plat-nomadik/timer.c
*
* Copyright (C) 2008 STMicroelectronics
* Copyright (C) 2010 Alessandro Rubini
@@ -75,7 +75,7 @@ static void nmdk_clkevt_mode(enum clock_event_mode mode,
cr = readl(mtu_base + MTU_CR(1));
writel(0, mtu_base + MTU_LR(1));
writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(1));
- writel(0x2, mtu_base + MTU_IMSC);
+ writel(1 << 1, mtu_base + MTU_IMSC);
break;
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
@@ -131,25 +131,23 @@ void __init nmdk_timer_init(void)
{
unsigned long rate;
struct clk *clk0;
- struct clk *clk1;
- u32 cr;
+ u32 cr = MTU_CRn_32BITS;
clk0 = clk_get_sys("mtu0", NULL);
BUG_ON(IS_ERR(clk0));
- clk1 = clk_get_sys("mtu1", NULL);
- BUG_ON(IS_ERR(clk1));
-
clk_enable(clk0);
- clk_enable(clk1);
/*
- * Tick rate is 2.4MHz for Nomadik and 110MHz for ux500:
- * use a divide-by-16 counter if it's more than 16MHz
+ * Tick rate is 2.4MHz for Nomadik and 2.4Mhz, 100MHz or 133 MHz
+ * for ux500.
+ * Use a divide-by-16 counter if the tick rate is more than 32MHz.
+ * At 32 MHz, the timer (with 32 bit counter) can be programmed
+ * to wake-up at a max 127s a head in time. Dividing a 2.4 MHz timer
+ * with 16 gives too low timer resolution.
*/
- cr = MTU_CRn_32BITS;;
rate = clk_get_rate(clk0);
- if (rate > 16 << 20) {
+ if (rate > 32000000) {
rate /= 16;
cr |= MTU_CRn_PRESCALE_16;
} else {
@@ -170,15 +168,8 @@ void __init nmdk_timer_init(void)
pr_err("timer: failed to initialize clock source %s\n",
nmdk_clksrc.name);
- /* Timer 1 is used for events, fix according to rate */
- cr = MTU_CRn_32BITS;
- rate = clk_get_rate(clk1);
- if (rate > 16 << 20) {
- rate /= 16;
- cr |= MTU_CRn_PRESCALE_16;
- } else {
- cr |= MTU_CRn_PRESCALE_1;
- }
+ /* Timer 1 is used for events */
+
clockevents_calc_mult_shift(&nmdk_clkevt, rate, MTU_MIN_RANGE);
writel(cr | MTU_CRn_ONESHOT, mtu_base + MTU_CR(1)); /* off, currently */