diff options
Diffstat (limited to 'arch/arm/kernel/smp_twd.c')
| -rw-r--r-- | arch/arm/kernel/smp_twd.c | 40 |
1 files changed, 39 insertions, 1 deletions
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index f0575610b17..a9783947c08 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -10,8 +10,10 @@ */ #include <linux/init.h> #include <linux/kernel.h> +#include <linux/clk.h> #include <linux/delay.h> #include <linux/device.h> +#include <linux/err.h> #include <linux/smp.h> #include <linux/jiffies.h> #include <linux/clockchips.h> @@ -25,6 +27,7 @@ /* set up by the platform code */ void __iomem *twd_base; +static struct clk *twd_clk; static unsigned long twd_timer_rate; static struct clock_event_device __percpu **twd_evt; @@ -140,6 +143,35 @@ static irqreturn_t twd_handler(int irq, void *dev_id) return IRQ_NONE; } +static struct clk *twd_get_clock(void) +{ + struct clk *clk; + int err; + + clk = clk_get_sys("smp_twd", NULL); + if (IS_ERR(clk)) { + pr_err("smp_twd: clock not found: %d\n", (int)PTR_ERR(clk)); + return clk; + } + + err = clk_prepare(clk); + if (err) { + pr_err("smp_twd: clock failed to prepare: %d\n", err); + clk_put(clk); + return ERR_PTR(err); + } + + err = clk_enable(clk); + if (err) { + pr_err("smp_twd: clock failed to enable: %d\n", err); + clk_unprepare(clk); + clk_put(clk); + return ERR_PTR(err); + } + + return clk; +} + /* * Setup the local clock events for a CPU. */ @@ -165,7 +197,13 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk) } } - twd_calibrate_rate(); + if (!twd_clk) + twd_clk = twd_get_clock(); + + if (!IS_ERR_OR_NULL(twd_clk)) + twd_timer_rate = clk_get_rate(twd_clk); + else + twd_calibrate_rate(); clk->name = "local_timer"; clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT | |