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author | Heiko Stuebner <heiko@sntech.de> | 2013-06-04 11:37:36 +0200 |
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committer | Heiko Stuebner <heiko@sntech.de> | 2013-06-12 13:47:22 +0200 |
commit | a8b447f2bbbba737ff4478f498d7f83c75a9461b (patch) | |
tree | b68792f27524250d1a9d3267ef3cf80f7a3cc946 /drivers/clocksource/dw_apb_timer_of.c | |
parent | clocksource: dw_apb_timer_of: enable the use the clocksource as sched clock (diff) | |
download | linux-a8b447f2bbbba737ff4478f498d7f83c75a9461b.tar.xz linux-a8b447f2bbbba737ff4478f498d7f83c75a9461b.zip |
clocksource: dw_apb_timer_of: add clock-handling
Add the possibility to get the clock-frequency from a timer clock instead
of specifying it as dt property. Additionally also add the possibility
to also define a controlling periphal clock for the timer block.
The clock-frequency property is kept to act as fallback if no clocks
are specified.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Diffstat (limited to 'drivers/clocksource/dw_apb_timer_of.c')
-rw-r--r-- | drivers/clocksource/dw_apb_timer_of.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c index d6c0fda76a7e..1964f8716966 100644 --- a/drivers/clocksource/dw_apb_timer_of.c +++ b/drivers/clocksource/dw_apb_timer_of.c @@ -20,6 +20,7 @@ #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> +#include <linux/clk.h> #include <asm/mach/time.h> #include <asm/sched_clock.h> @@ -27,14 +28,37 @@ static void timer_get_base_and_rate(struct device_node *np, void __iomem **base, u32 *rate) { + struct clk *timer_clk; + struct clk *pclk; + *base = of_iomap(np, 0); if (!*base) panic("Unable to map regs for %s", np->name); + /* + * Not all implementations use a periphal clock, so don't panic + * if it's not present + */ + pclk = of_clk_get_by_name(np, "pclk"); + if (!IS_ERR(pclk)) + if (clk_prepare_enable(pclk)) + pr_warn("pclk for %s is present, but could not be activated\n", + np->name); + + timer_clk = of_clk_get_by_name(np, "timer"); + if (IS_ERR(timer_clk)) + goto try_clock_freq; + + if (!clk_prepare_enable(timer_clk)) { + *rate = clk_get_rate(timer_clk); + return; + } + +try_clock_freq: if (of_property_read_u32(np, "clock-freq", rate) && of_property_read_u32(np, "clock-frequency", rate)) - panic("No clock-frequency property for %s", np->name); + panic("No clock nor clock-frequency property for %s", np->name); } static void add_clockevent(struct device_node *event_timer) |