scsi: ufs: do clock gating only after hibern8 (e9239e3f) · Commits · e / devices / android_kernel_sony_msm8998

drivers/scsi/ufs/ufshcd.c

+44 −24

Original line number	Diff line number	Diff line
		@@ -1176,6 +1176,12 @@ static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up)
		return ret;
		}

		static inline void ufshcd_cancel_gate_work(struct ufs_hba *hba)
		{
		hrtimer_cancel(&hba->clk_gating.gate_hrtimer);
		cancel_work_sync(&hba->clk_gating.gate_work);
		}

		static void ufshcd_ungate_work(struct work_struct *work)
		{
		int ret;
		@@ -1183,7 +1189,7 @@ static void ufshcd_ungate_work(struct work_struct *work)
		struct ufs_hba *hba = container_of(work, struct ufs_hba,
		clk_gating.ungate_work);

		cancel_delayed_work_sync(&hba->clk_gating.gate_work);
		ufshcd_cancel_gate_work(hba);

		spin_lock_irqsave(hba->host->host_lock, flags);
		if (hba->clk_gating.state == CLKS_ON) {
		@@ -1254,14 +1260,18 @@ start:
		}
		break;
		case REQ_CLKS_OFF:
		if (cancel_delayed_work(&hba->clk_gating.gate_work)) {
		/*
		* If the timer was active but the callback was not running
		* we have nothing to do, just change state and return.
		*/
		if (hrtimer_try_to_cancel(&hba->clk_gating.gate_hrtimer) == 1) {
		hba->clk_gating.state = CLKS_ON;
		trace_ufshcd_clk_gating(dev_name(hba->dev),
		hba->clk_gating.state);
		break;
		}
		/*
		* If we here, it means gating work is either done or
		* If we are here, it means gating work is either done or
		* currently running. Hence, fall through to cancel gating
		* work and to enable clocks.
		*/
		@@ -1301,7 +1311,7 @@ EXPORT_SYMBOL_GPL(ufshcd_hold);
		static void ufshcd_gate_work(struct work_struct *work)
		{
		struct ufs_hba *hba = container_of(work, struct ufs_hba,
		clk_gating.gate_work.work);
		clk_gating.gate_work);
		unsigned long flags;

		spin_lock_irqsave(hba->host->host_lock, flags);
		@@ -1394,8 +1404,9 @@ static void __ufshcd_release(struct ufs_hba *hba, bool no_sched)
		hba->clk_gating.state = REQ_CLKS_OFF;
		trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state);

		schedule_delayed_work(&hba->clk_gating.gate_work,
		msecs_to_jiffies(hba->clk_gating.delay_ms));
		hrtimer_start(&hba->clk_gating.gate_hrtimer,
		ms_to_ktime(hba->clk_gating.delay_ms),
		HRTIMER_MODE_REL);
		}

		void ufshcd_release(struct ufs_hba *hba, bool no_sched)
		@@ -1523,6 +1534,17 @@ out:
		return count;
		}

		static enum hrtimer_restart ufshcd_clkgate_hrtimer_handler(
		struct hrtimer *timer)
		{
		struct ufs_hba *hba = container_of(timer, struct ufs_hba,
		clk_gating.gate_hrtimer);

		schedule_work(&hba->clk_gating.gate_work);

		return HRTIMER_NORESTART;
		}

		static void ufshcd_init_clk_gating(struct ufs_hba *hba)
		{
		struct ufs_clk_gating *gating = &hba->clk_gating;
		@@ -1539,27 +1561,25 @@ static void ufshcd_init_clk_gating(struct ufs_hba *hba)
		if (ufshcd_is_auto_hibern8_supported(hba))
		hba->caps &= ~UFSHCD_CAP_HIBERN8_WITH_CLK_GATING;

		INIT_DELAYED_WORK(&gating->gate_work, ufshcd_gate_work);
		INIT_WORK(&gating->gate_work, ufshcd_gate_work);
		INIT_WORK(&gating->ungate_work, ufshcd_ungate_work);
		/*
		* Clock gating work must be executed only after auto hibern8
		* timeout has expired in the hardware or after aggressive
		* hibern8 on idle software timeout. Using jiffy based low
		* resolution delayed work is not reliable to guarantee this,
		* hence use a high resolution timer to make sure we schedule
		* the gate work precisely more than hibern8 timeout.
		*
		* Always make sure gating->delay_ms > hibern8_on_idle->delay_ms
		*/
		hrtimer_init(&gating->gate_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
		gating->gate_hrtimer.function = ufshcd_clkgate_hrtimer_handler;

		gating->is_enabled = true;

		/*
		* Scheduling the delayed work after 1 jiffies will make the work to
		* get schedule any time from 0ms to 1000/HZ ms which is not desirable
		* for hibern8 enter work as it may impact the performance if it gets
		* scheduled almost immediately. Hence make sure that hibern8 enter
		* work gets scheduled atleast after 2 jiffies (any time between
		* 1000/HZ ms to 2000/HZ ms).
		*/
		gating->delay_ms_pwr_save = jiffies_to_msecs(
		max_t(unsigned long,
		msecs_to_jiffies(UFSHCD_CLK_GATING_DELAY_MS_PWR_SAVE),
		2));
		gating->delay_ms_perf = jiffies_to_msecs(
		max_t(unsigned long,
		msecs_to_jiffies(UFSHCD_CLK_GATING_DELAY_MS_PERF),
		2));
		gating->delay_ms_pwr_save = UFSHCD_CLK_GATING_DELAY_MS_PWR_SAVE;
		gating->delay_ms_perf = UFSHCD_CLK_GATING_DELAY_MS_PERF;

		/* start with performance mode */
		gating->delay_ms = gating->delay_ms_perf;
		@@ -1616,8 +1636,8 @@ static void ufshcd_exit_clk_gating(struct ufs_hba *hba)
		device_remove_file(hba->dev, &hba->clk_gating.delay_attr);
		}
		device_remove_file(hba->dev, &hba->clk_gating.enable_attr);
		ufshcd_cancel_gate_work(hba);
		cancel_work_sync(&hba->clk_gating.ungate_work);
		cancel_delayed_work_sync(&hba->clk_gating.gate_work);
		}

		static void ufshcd_set_auto_hibern8_timer(struct ufs_hba *hba, u32 delay)

drivers/scsi/ufs/ufshcd.h

+6 −3

Original line number	Diff line number	Diff line
		@@ -39,6 +39,7 @@

		#include <linux/module.h>
		#include <linux/kernel.h>
		#include <linux/hrtimer.h>
		#include <linux/init.h>
		#include <linux/interrupt.h>
		#include <linux/io.h>
		@@ -396,8 +397,9 @@ enum clk_gating_state {

		/**
		* struct ufs_clk_gating - UFS clock gating related info
		* @gate_work: worker to turn off clocks after some delay as specified in
		* delay_ms
		* @gate_hrtimer: hrtimer to invoke @gate_work after some delay as
		* specified in @delay_ms
		* @gate_work: worker to turn off clocks
		* @ungate_work: worker to turn on clocks that will be used in case of
		* interrupt context
		* @state: the current clocks state
		@@ -415,7 +417,8 @@ enum clk_gating_state {
		* completion before gating clocks.
		*/
		struct ufs_clk_gating {
		struct delayed_work gate_work;
		struct hrtimer gate_hrtimer;
		struct work_struct gate_work;
		struct work_struct ungate_work;
		enum clk_gating_state state;
		unsigned long delay_ms;