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| author | Heiko Stuebner <heiko@sntech.de> | 2013-06-04 11:37:02 +0200 |
|---|---|---|
| committer | Heiko Stuebner <heiko@sntech.de> | 2013-06-12 13:47:13 +0200 |
| commit | a1198f83407ae3421f3f58355a0f296d5ea6249c (patch) | |
| tree | 6760cab93aa90b7456917923315632b81c7e0b5d /drivers/clocksource | |
| parent | e4aa937ec75df0eea0bee03bffa3303ad36c986b (diff) | |
| download | linux-stable-a1198f83407ae3421f3f58355a0f296d5ea6249c.tar.gz linux-stable-a1198f83407ae3421f3f58355a0f296d5ea6249c.tar.bz2 linux-stable-a1198f83407ae3421f3f58355a0f296d5ea6249c.zip | |
clocksource: dw_apb_timer_of: enable the use the clocksource as sched clock
Currently the dw_apb_timer always expects a separate special timer to be
availbable for the sched_clock. Some devices using dw_apb_timers do not
have this sptimer but can use the clocksource as sched_clock instead.
Therefore enable the driver to distiguish between devices with and without
sptimer based on the devicetree data and select the correct timer as
sched_clock.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Diffstat (limited to 'drivers/clocksource')
| -rw-r--r-- | drivers/clocksource/dw_apb_timer_of.c | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c index ab09ed3742ee..d6c0fda76a7e 100644 --- a/drivers/clocksource/dw_apb_timer_of.c +++ b/drivers/clocksource/dw_apb_timer_of.c @@ -57,6 +57,9 @@ static void add_clockevent(struct device_node *event_timer) dw_apb_clockevent_register(ced); } +static void __iomem *sched_io_base; +static u32 sched_rate; + static void add_clocksource(struct device_node *source_timer) { void __iomem *iobase; @@ -71,9 +74,15 @@ static void add_clocksource(struct device_node *source_timer) dw_apb_clocksource_start(cs); dw_apb_clocksource_register(cs); -} -static void __iomem *sched_io_base; + /* + * Fallback to use the clocksource as sched_clock if no separate + * timer is found. sched_io_base then points to the current_value + * register of the clocksource timer. + */ + sched_io_base = iobase + 0x04; + sched_rate = rate; +} static u32 read_sched_clock(void) { @@ -89,16 +98,15 @@ static const struct of_device_id sptimer_ids[] __initconst = { static void init_sched_clock(void) { struct device_node *sched_timer; - u32 rate; sched_timer = of_find_matching_node(NULL, sptimer_ids); - if (!sched_timer) - panic("No RTC for sched clock to use"); - - timer_get_base_and_rate(sched_timer, &sched_io_base, &rate); - of_node_put(sched_timer); + if (sched_timer) { + timer_get_base_and_rate(sched_timer, &sched_io_base, + &sched_rate); + of_node_put(sched_timer); + } - setup_sched_clock(read_sched_clock, 32, rate); + setup_sched_clock(read_sched_clock, 32, sched_rate); } static const struct of_device_id osctimer_ids[] __initconst = { |