From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko =?utf-8?q?St=C3=BCbner?= Subject: [PATCH 01/10] clocksource: dw_apb_timer_of: use the clocksource as sched clock if necessary Date: Mon, 3 Jun 2013 00:56:02 +0200 Message-ID: <201306030056.03522.heiko@sntech.de> References: <201306030055.15413.heiko@sntech.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <201306030055.15413.heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" Cc: Mike Turquette , Seungwon Jeon , linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Herring , Jaehoon Chung , John Stultz , Grant Likely , Russell King , Thomas Gleixner , Chris Ball , devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org List-Id: linux-mmc@vger.kernel.org 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 the sptimer but can use the clocksource as sched_clock. Therefore this patch adds using the clocksource timer as a fallback if no usable sched timer is found. Signed-off-by: Heiko Stuebner --- 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 ab09ed3..d6c0fda 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 = { -- 1.7.2.3