From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752950AbbETLCZ (ORCPT ); Wed, 20 May 2015 07:02:25 -0400 Received: from mail-la0-f50.google.com ([209.85.215.50]:35258 "EHLO mail-la0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751530AbbETLCX (ORCPT ); Wed, 20 May 2015 07:02:23 -0400 MIME-Version: 1.0 In-Reply-To: <1431763110-443-5-git-send-email-yingjoe.chen@mediatek.com> References: <1431763110-443-1-git-send-email-yingjoe.chen@mediatek.com> <1431763110-443-5-git-send-email-yingjoe.chen@mediatek.com> Date: Wed, 20 May 2015 13:02:21 +0200 Message-ID: Subject: Re: [PATCH v2 4/9] clocksource: mediatek: Use GPT as sched clock source From: Matthias Brugger To: Yingjoe Chen Cc: Mark Rutland , Thomas Gleixner , Russell King , Arnd Bergmann , Olof Johansson , "devicetree@vger.kernel.org" , Stephen Boyd , Pawel Moll , Catalin Marinas , Daniel Lezcano , "linux-kernel@vger.kernel.org" , Marc Carino , Rob Herring , linux-mediatek@lists.infradead.org, Sascha Hauer , srv_heupstream , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2015-05-16 9:58 GMT+02:00 Yingjoe Chen : > When cpu is in deep idle, arch timer will stop counting. Setup GPT as > sched clock source so it can keep counting in idle. > > Signed-off-by: Yingjoe Chen > --- > drivers/clocksource/mtk_timer.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c > index 91206f9..fe7cf72 100644 > --- a/drivers/clocksource/mtk_timer.c > +++ b/drivers/clocksource/mtk_timer.c > @@ -24,6 +24,7 @@ > #include > #include > #include > +#include > #include > > #define GPT_IRQ_EN_REG 0x00 > @@ -59,6 +60,13 @@ struct mtk_clock_event_device { > struct clock_event_device dev; > }; > > +static void __iomem *gpt_base __read_mostly; > + > +static u64 notrace mtk_read_sched_clock(void) > +{ > + return readl_relaxed(gpt_base + TIMER_CNT_REG(GPT_CLK_SRC)); > +} > + > static inline struct mtk_clock_event_device *to_mtk_clk( > struct clock_event_device *c) > { > @@ -243,6 +251,8 @@ static void __init mtk_timer_init(struct device_node *node) > mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN, 1); > clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC), > node->name, rate, 300, 32, clocksource_mmio_readl_up); > + gpt_base = evt->gpt_base; This is really hacky. We should clean up the code and provide mtk_clock_event_device globally. Please add the patch below, which does exactly this. ---- 8< ---------------- >8 ------ >>From 631e7bf4e5d9456d0bb4a29b2dee4b84e8c052bd Mon Sep 17 00:00:00 2001 From: Matthias Brugger Date: Wed, 20 May 2015 12:43:16 +0200 Subject: [PATCH] clocksource: mediatek: Define mtk_clock_event_device globally Sched clock code, especially sched_clock_register does not allow to pass a pointer to actual_read_sched_clock. So if in the driver the register base address is not globally defined, we are not able to read the scheduler clock register. This patch sets the mtk_clock_event_device struct globally for the driver, to be able to read the register. Signed-off-by: Matthias Brugger --- drivers/clocksource/mtk_timer.c | 50 +++++++++++++++-------------------------- 1 file changed, 18 insertions(+), 32 deletions(-) diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c index 68ab423..c5f5b40 100644 --- a/drivers/clocksource/mtk_timer.c +++ b/drivers/clocksource/mtk_timer.c @@ -59,13 +59,9 @@ struct mtk_clock_event_device { struct clock_event_device dev; }; -static inline struct mtk_clock_event_device *to_mtk_clk( - struct clock_event_device *c) -{ - return container_of(c, struct mtk_clock_event_device, dev); -} +struct mtk_clock_event_device *evt; -static void mtk_clkevt_time_stop(struct mtk_clock_event_device *evt, u8 timer) +static void mtk_clkevt_time_stop(u8 timer) { u32 val; @@ -74,14 +70,12 @@ static void mtk_clkevt_time_stop(struct mtk_clock_event_device *evt, u8 timer) TIMER_CTRL_REG(timer)); } -static void mtk_clkevt_time_setup(struct mtk_clock_event_device *evt, - unsigned long delay, u8 timer) +static void mtk_clkevt_time_setup(unsigned long delay, u8 timer) { writel(delay, evt->gpt_base + TIMER_CMP_REG(timer)); } -static void mtk_clkevt_time_start(struct mtk_clock_event_device *evt, - bool periodic, u8 timer) +static void mtk_clkevt_time_start(bool periodic, u8 timer) { u32 val; @@ -105,14 +99,12 @@ static void mtk_clkevt_time_start(struct mtk_clock_event_device *evt, static void mtk_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *clk) { - struct mtk_clock_event_device *evt = to_mtk_clk(clk); - - mtk_clkevt_time_stop(evt, GPT_CLK_EVT); + mtk_clkevt_time_stop(GPT_CLK_EVT); switch (mode) { case CLOCK_EVT_MODE_PERIODIC: - mtk_clkevt_time_setup(evt, evt->ticks_per_jiffy, GPT_CLK_EVT); - mtk_clkevt_time_start(evt, true, GPT_CLK_EVT); + mtk_clkevt_time_setup(evt->ticks_per_jiffy, GPT_CLK_EVT); + mtk_clkevt_time_start(true, GPT_CLK_EVT); break; case CLOCK_EVT_MODE_ONESHOT: /* Timer is enabled in set_next_event */ @@ -128,19 +120,15 @@ static void mtk_clkevt_mode(enum clock_event_mode mode, static int mtk_clkevt_next_event(unsigned long event, struct clock_event_device *clk) { - struct mtk_clock_event_device *evt = to_mtk_clk(clk); - - mtk_clkevt_time_stop(evt, GPT_CLK_EVT); - mtk_clkevt_time_setup(evt, event, GPT_CLK_EVT); - mtk_clkevt_time_start(evt, false, GPT_CLK_EVT); + mtk_clkevt_time_stop(GPT_CLK_EVT); + mtk_clkevt_time_setup(event, GPT_CLK_EVT); + mtk_clkevt_time_start(false, GPT_CLK_EVT); return 0; } static irqreturn_t mtk_timer_interrupt(int irq, void *dev_id) { - struct mtk_clock_event_device *evt = dev_id; - /* Acknowledge timer0 irq */ writel(GPT_IRQ_ACK(GPT_CLK_EVT), evt->gpt_base + GPT_IRQ_ACK_REG); evt->dev.event_handler(&evt->dev); @@ -148,7 +136,7 @@ static irqreturn_t mtk_timer_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } -static void mtk_timer_global_reset(struct mtk_clock_event_device *evt) +static inline void mtk_timer_global_reset(void) { /* Disable all interrupts */ writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG); @@ -156,8 +144,7 @@ static void mtk_timer_global_reset(struct mtk_clock_event_device *evt) writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG); } -static void -mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option) +static void mtk_timer_setup(u8 timer, u8 option) { writel(TIMER_CTRL_CLEAR | TIMER_CTRL_DISABLE, evt->gpt_base + TIMER_CTRL_REG(timer)); @@ -171,7 +158,7 @@ mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option) evt->gpt_base + TIMER_CTRL_REG(timer)); } -static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer) +static void mtk_timer_enable_irq(u8 timer) { u32 val; @@ -182,7 +169,6 @@ static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer) static void __init mtk_timer_init(struct device_node *node) { - struct mtk_clock_event_device *evt; struct resource res; unsigned long rate = 0; struct clk *clk; @@ -224,10 +210,10 @@ static void __init mtk_timer_init(struct device_node *node) } rate = clk_get_rate(clk); - mtk_timer_global_reset(evt); + mtk_timer_global_reset(); if (request_irq(evt->dev.irq, mtk_timer_interrupt, - IRQF_TIMER | IRQF_IRQPOLL, "mtk_timer", evt)) { + IRQF_TIMER | IRQF_IRQPOLL, "mtk_timer", NULL)) { pr_warn("failed to setup irq %d\n", evt->dev.irq); goto err_clk_disable; } @@ -235,16 +221,16 @@ static void __init mtk_timer_init(struct device_node *node) evt->ticks_per_jiffy = DIV_ROUND_UP(rate, HZ); /* Configure clock source */ - mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN); + mtk_timer_setup(GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN); clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC), node->name, rate, 300, 32, clocksource_mmio_readl_up); /* Configure clock event */ - mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT); + mtk_timer_setup(GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT); clockevents_config_and_register(&evt->dev, rate, 0x3, 0xffffffff); - mtk_timer_enable_irq(evt, GPT_CLK_EVT); + mtk_timer_enable_irq(GPT_CLK_EVT); return; -- 1.9.1