From ba8f20c2eb4158a443e9d6a909aee5010efa0c69 Mon Sep 17 00:00:00 2001 From: Preeti U Murthy Date: Fri, 7 Feb 2014 13:36:52 +0530 Subject: cpuidle: Handle clockevents_notify(BROADCAST_ENTER) failure Some archs set the CPUIDLE_FLAG_TIMER_STOP flag for idle states in which the local timers stop. The cpuidle_idle_call() currently handles such idle states by calling into the broadcast framework so as to wakeup CPUs at their next wakeup event. With the hrtimer mode of broadcast, the BROADCAST_ENTER call into the broadcast frameowork can fail for archs that do not have an external clock device to handle wakeups and the CPU in question has thus to be made the stand by CPU. This patch handles such cases by failing the call into cpuidle so that the arch can take some default action. The arch will certainly not enter a similar idle state because a failed cpuidle call will also implicitly indicate that the broadcast framework has not registered this CPU to be woken up. Hence we are safe if we fail the cpuidle call. In the process move the functions that trace idle statistics just before and after the entry and exit into idle states respectively. In other scenarios where the call to cpuidle fails, we end up not tracing idle entry and exit since a decision on an idle state could not be taken. Similarly when the call to broadcast framework fails, we skip tracing idle statistics because we are in no further position to take a decision on an alternative idle state to enter into. Signed-off-by: Preeti U Murthy Cc: deepthi@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: fweisbec@gmail.com Cc: paulus@samba.org Cc: srivatsa.bhat@linux.vnet.ibm.com Cc: svaidy@linux.vnet.ibm.com Cc: peterz@infradead.org Cc: benh@kernel.crashing.org Acked-by: Rafael J. Wysocki Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20140207080652.17187.66344.stgit@preeti.in.ibm.com Signed-off-by: Thomas Gleixner --- drivers/cpuidle/cpuidle.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index a55e68f..09d05ab 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -140,12 +140,14 @@ int cpuidle_idle_call(void) return 0; } - trace_cpu_idle_rcuidle(next_state, dev->cpu); - broadcast = !!(drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP); - if (broadcast) - clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); + if (broadcast && + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu)) + return -EBUSY; + + + trace_cpu_idle_rcuidle(next_state, dev->cpu); if (cpuidle_state_is_coupled(dev, drv, next_state)) entered_state = cpuidle_enter_state_coupled(dev, drv, @@ -153,11 +155,11 @@ int cpuidle_idle_call(void) else entered_state = cpuidle_enter_state(dev, drv, next_state); + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu); + if (broadcast) clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); - trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu); - /* give the governor an opportunity to reflect on the outcome */ if (cpuidle_curr_governor->reflect) cpuidle_curr_governor->reflect(dev, entered_state); -- cgit v1.1 From 7b52ad2efa4926ca7f399e5e63cf9a587396cd87 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Mon, 6 Jan 2014 14:56:17 -0800 Subject: clocksource: arch_timer: Set dynamic irq affinity on mmio clockevent Set the CLOCK_EVT_FEAT_DYNIRQ flag on the memory mapped clockevent so that we save power by waking up the CPU with the next event when this timer is used in broadcast mode. Signed-off-by: Stephen Boyd Signed-off-by: Daniel Lezcano --- drivers/clocksource/arm_arch_timer.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 95fb944..57e823c 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -277,6 +277,7 @@ static void __arch_timer_setup(unsigned type, clk->set_next_event = arch_timer_set_next_event_phys; } } else { + clk->features |= CLOCK_EVT_FEAT_DYNIRQ; clk->name = "arch_mem_timer"; clk->rating = 400; clk->cpumask = cpu_all_mask; -- cgit v1.1 From 9affbd2458eca452e63b108e1a6258cf370f6eb9 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Tue, 21 Jan 2014 15:04:14 +0100 Subject: ARM: u300: move timer driver to clocksource Move the U300 timer driver down to the clocksource driver subsystem and keep arch/arm clean. Cc: Daniel Lezcano Cc: Thomas Gleixner Signed-off-by: Linus Walleij Signed-off-by: Daniel Lezcano --- drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-u300.c | 447 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 448 insertions(+) create mode 100644 drivers/clocksource/timer-u300.c (limited to 'drivers') diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index c7ca50a..01e5435 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_ARCH_MARCO) += timer-marco.o obj-$(CONFIG_ARCH_MOXART) += moxart_timer.o obj-$(CONFIG_ARCH_MXS) += mxs_timer.o obj-$(CONFIG_ARCH_PRIMA2) += timer-prima2.o +obj-$(CONFIG_ARCH_U300) += timer-u300.o obj-$(CONFIG_SUN4I_TIMER) += sun4i_timer.o obj-$(CONFIG_SUN5I_HSTIMER) += timer-sun5i.o obj-$(CONFIG_ARCH_TEGRA) += tegra20_timer.o diff --git a/drivers/clocksource/timer-u300.c b/drivers/clocksource/timer-u300.c new file mode 100644 index 0000000..e63d469 --- /dev/null +++ b/drivers/clocksource/timer-u300.c @@ -0,0 +1,447 @@ +/* + * Copyright (C) 2007-2009 ST-Ericsson AB + * License terms: GNU General Public License (GPL) version 2 + * Timer COH 901 328, runs the OS timer interrupt. + * Author: Linus Walleij + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Generic stuff */ +#include +#include + +/* + * APP side special timer registers + * This timer contains four timers which can fire an interrupt each. + * OS (operating system) timer @ 32768 Hz + * DD (device driver) timer @ 1 kHz + * GP1 (general purpose 1) timer @ 1MHz + * GP2 (general purpose 2) timer @ 1MHz + */ + +/* Reset OS Timer 32bit (-/W) */ +#define U300_TIMER_APP_ROST (0x0000) +#define U300_TIMER_APP_ROST_TIMER_RESET (0x00000000) +/* Enable OS Timer 32bit (-/W) */ +#define U300_TIMER_APP_EOST (0x0004) +#define U300_TIMER_APP_EOST_TIMER_ENABLE (0x00000000) +/* Disable OS Timer 32bit (-/W) */ +#define U300_TIMER_APP_DOST (0x0008) +#define U300_TIMER_APP_DOST_TIMER_DISABLE (0x00000000) +/* OS Timer Mode Register 32bit (-/W) */ +#define U300_TIMER_APP_SOSTM (0x000c) +#define U300_TIMER_APP_SOSTM_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_SOSTM_MODE_ONE_SHOT (0x00000001) +/* OS Timer Status Register 32bit (R/-) */ +#define U300_TIMER_APP_OSTS (0x0010) +#define U300_TIMER_APP_OSTS_TIMER_STATE_MASK (0x0000000F) +#define U300_TIMER_APP_OSTS_TIMER_STATE_IDLE (0x00000001) +#define U300_TIMER_APP_OSTS_TIMER_STATE_ACTIVE (0x00000002) +#define U300_TIMER_APP_OSTS_ENABLE_IND (0x00000010) +#define U300_TIMER_APP_OSTS_MODE_MASK (0x00000020) +#define U300_TIMER_APP_OSTS_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_OSTS_MODE_ONE_SHOT (0x00000020) +#define U300_TIMER_APP_OSTS_IRQ_ENABLED_IND (0x00000040) +#define U300_TIMER_APP_OSTS_IRQ_PENDING_IND (0x00000080) +/* OS Timer Current Count Register 32bit (R/-) */ +#define U300_TIMER_APP_OSTCC (0x0014) +/* OS Timer Terminal Count Register 32bit (R/W) */ +#define U300_TIMER_APP_OSTTC (0x0018) +/* OS Timer Interrupt Enable Register 32bit (-/W) */ +#define U300_TIMER_APP_OSTIE (0x001c) +#define U300_TIMER_APP_OSTIE_IRQ_DISABLE (0x00000000) +#define U300_TIMER_APP_OSTIE_IRQ_ENABLE (0x00000001) +/* OS Timer Interrupt Acknowledge Register 32bit (-/W) */ +#define U300_TIMER_APP_OSTIA (0x0020) +#define U300_TIMER_APP_OSTIA_IRQ_ACK (0x00000080) + +/* Reset DD Timer 32bit (-/W) */ +#define U300_TIMER_APP_RDDT (0x0040) +#define U300_TIMER_APP_RDDT_TIMER_RESET (0x00000000) +/* Enable DD Timer 32bit (-/W) */ +#define U300_TIMER_APP_EDDT (0x0044) +#define U300_TIMER_APP_EDDT_TIMER_ENABLE (0x00000000) +/* Disable DD Timer 32bit (-/W) */ +#define U300_TIMER_APP_DDDT (0x0048) +#define U300_TIMER_APP_DDDT_TIMER_DISABLE (0x00000000) +/* DD Timer Mode Register 32bit (-/W) */ +#define U300_TIMER_APP_SDDTM (0x004c) +#define U300_TIMER_APP_SDDTM_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_SDDTM_MODE_ONE_SHOT (0x00000001) +/* DD Timer Status Register 32bit (R/-) */ +#define U300_TIMER_APP_DDTS (0x0050) +#define U300_TIMER_APP_DDTS_TIMER_STATE_MASK (0x0000000F) +#define U300_TIMER_APP_DDTS_TIMER_STATE_IDLE (0x00000001) +#define U300_TIMER_APP_DDTS_TIMER_STATE_ACTIVE (0x00000002) +#define U300_TIMER_APP_DDTS_ENABLE_IND (0x00000010) +#define U300_TIMER_APP_DDTS_MODE_MASK (0x00000020) +#define U300_TIMER_APP_DDTS_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_DDTS_MODE_ONE_SHOT (0x00000020) +#define U300_TIMER_APP_DDTS_IRQ_ENABLED_IND (0x00000040) +#define U300_TIMER_APP_DDTS_IRQ_PENDING_IND (0x00000080) +/* DD Timer Current Count Register 32bit (R/-) */ +#define U300_TIMER_APP_DDTCC (0x0054) +/* DD Timer Terminal Count Register 32bit (R/W) */ +#define U300_TIMER_APP_DDTTC (0x0058) +/* DD Timer Interrupt Enable Register 32bit (-/W) */ +#define U300_TIMER_APP_DDTIE (0x005c) +#define U300_TIMER_APP_DDTIE_IRQ_DISABLE (0x00000000) +#define U300_TIMER_APP_DDTIE_IRQ_ENABLE (0x00000001) +/* DD Timer Interrupt Acknowledge Register 32bit (-/W) */ +#define U300_TIMER_APP_DDTIA (0x0060) +#define U300_TIMER_APP_DDTIA_IRQ_ACK (0x00000080) + +/* Reset GP1 Timer 32bit (-/W) */ +#define U300_TIMER_APP_RGPT1 (0x0080) +#define U300_TIMER_APP_RGPT1_TIMER_RESET (0x00000000) +/* Enable GP1 Timer 32bit (-/W) */ +#define U300_TIMER_APP_EGPT1 (0x0084) +#define U300_TIMER_APP_EGPT1_TIMER_ENABLE (0x00000000) +/* Disable GP1 Timer 32bit (-/W) */ +#define U300_TIMER_APP_DGPT1 (0x0088) +#define U300_TIMER_APP_DGPT1_TIMER_DISABLE (0x00000000) +/* GP1 Timer Mode Register 32bit (-/W) */ +#define U300_TIMER_APP_SGPT1M (0x008c) +#define U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT (0x00000001) +/* GP1 Timer Status Register 32bit (R/-) */ +#define U300_TIMER_APP_GPT1S (0x0090) +#define U300_TIMER_APP_GPT1S_TIMER_STATE_MASK (0x0000000F) +#define U300_TIMER_APP_GPT1S_TIMER_STATE_IDLE (0x00000001) +#define U300_TIMER_APP_GPT1S_TIMER_STATE_ACTIVE (0x00000002) +#define U300_TIMER_APP_GPT1S_ENABLE_IND (0x00000010) +#define U300_TIMER_APP_GPT1S_MODE_MASK (0x00000020) +#define U300_TIMER_APP_GPT1S_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_GPT1S_MODE_ONE_SHOT (0x00000020) +#define U300_TIMER_APP_GPT1S_IRQ_ENABLED_IND (0x00000040) +#define U300_TIMER_APP_GPT1S_IRQ_PENDING_IND (0x00000080) +/* GP1 Timer Current Count Register 32bit (R/-) */ +#define U300_TIMER_APP_GPT1CC (0x0094) +/* GP1 Timer Terminal Count Register 32bit (R/W) */ +#define U300_TIMER_APP_GPT1TC (0x0098) +/* GP1 Timer Interrupt Enable Register 32bit (-/W) */ +#define U300_TIMER_APP_GPT1IE (0x009c) +#define U300_TIMER_APP_GPT1IE_IRQ_DISABLE (0x00000000) +#define U300_TIMER_APP_GPT1IE_IRQ_ENABLE (0x00000001) +/* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */ +#define U300_TIMER_APP_GPT1IA (0x00a0) +#define U300_TIMER_APP_GPT1IA_IRQ_ACK (0x00000080) + +/* Reset GP2 Timer 32bit (-/W) */ +#define U300_TIMER_APP_RGPT2 (0x00c0) +#define U300_TIMER_APP_RGPT2_TIMER_RESET (0x00000000) +/* Enable GP2 Timer 32bit (-/W) */ +#define U300_TIMER_APP_EGPT2 (0x00c4) +#define U300_TIMER_APP_EGPT2_TIMER_ENABLE (0x00000000) +/* Disable GP2 Timer 32bit (-/W) */ +#define U300_TIMER_APP_DGPT2 (0x00c8) +#define U300_TIMER_APP_DGPT2_TIMER_DISABLE (0x00000000) +/* GP2 Timer Mode Register 32bit (-/W) */ +#define U300_TIMER_APP_SGPT2M (0x00cc) +#define U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_SGPT2M_MODE_ONE_SHOT (0x00000001) +/* GP2 Timer Status Register 32bit (R/-) */ +#define U300_TIMER_APP_GPT2S (0x00d0) +#define U300_TIMER_APP_GPT2S_TIMER_STATE_MASK (0x0000000F) +#define U300_TIMER_APP_GPT2S_TIMER_STATE_IDLE (0x00000001) +#define U300_TIMER_APP_GPT2S_TIMER_STATE_ACTIVE (0x00000002) +#define U300_TIMER_APP_GPT2S_ENABLE_IND (0x00000010) +#define U300_TIMER_APP_GPT2S_MODE_MASK (0x00000020) +#define U300_TIMER_APP_GPT2S_MODE_CONTINUOUS (0x00000000) +#define U300_TIMER_APP_GPT2S_MODE_ONE_SHOT (0x00000020) +#define U300_TIMER_APP_GPT2S_IRQ_ENABLED_IND (0x00000040) +#define U300_TIMER_APP_GPT2S_IRQ_PENDING_IND (0x00000080) +/* GP2 Timer Current Count Register 32bit (R/-) */ +#define U300_TIMER_APP_GPT2CC (0x00d4) +/* GP2 Timer Terminal Count Register 32bit (R/W) */ +#define U300_TIMER_APP_GPT2TC (0x00d8) +/* GP2 Timer Interrupt Enable Register 32bit (-/W) */ +#define U300_TIMER_APP_GPT2IE (0x00dc) +#define U300_TIMER_APP_GPT2IE_IRQ_DISABLE (0x00000000) +#define U300_TIMER_APP_GPT2IE_IRQ_ENABLE (0x00000001) +/* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */ +#define U300_TIMER_APP_GPT2IA (0x00e0) +#define U300_TIMER_APP_GPT2IA_IRQ_ACK (0x00000080) + +/* Clock request control register - all four timers */ +#define U300_TIMER_APP_CRC (0x100) +#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE (0x00000001) + +static void __iomem *u300_timer_base; + +struct u300_clockevent_data { + struct clock_event_device cevd; + unsigned ticks_per_jiffy; +}; + +/* + * The u300_set_mode() function is always called first, if we + * have oneshot timer active, the oneshot scheduling function + * u300_set_next_event() is called immediately after. + */ +static void u300_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + struct u300_clockevent_data *cevdata = + container_of(evt, struct u300_clockevent_data, cevd); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + /* Disable interrupts on GPT1 */ + writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Disable GP1 while we're reprogramming it. */ + writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE, + u300_timer_base + U300_TIMER_APP_DGPT1); + /* + * Set the periodic mode to a certain number of ticks per + * jiffy. + */ + writel(cevdata->ticks_per_jiffy, + u300_timer_base + U300_TIMER_APP_GPT1TC); + /* + * Set continuous mode, so the timer keeps triggering + * interrupts. + */ + writel(U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS, + u300_timer_base + U300_TIMER_APP_SGPT1M); + /* Enable timer interrupts */ + writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Then enable the OS timer again */ + writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE, + u300_timer_base + U300_TIMER_APP_EGPT1); + break; + case CLOCK_EVT_MODE_ONESHOT: + /* Just break; here? */ + /* + * The actual event will be programmed by the next event hook, + * so we just set a dummy value somewhere at the end of the + * universe here. + */ + /* Disable interrupts on GPT1 */ + writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Disable GP1 while we're reprogramming it. */ + writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE, + u300_timer_base + U300_TIMER_APP_DGPT1); + /* + * Expire far in the future, u300_set_next_event() will be + * called soon... + */ + writel(0xFFFFFFFF, u300_timer_base + U300_TIMER_APP_GPT1TC); + /* We run one shot per tick here! */ + writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT, + u300_timer_base + U300_TIMER_APP_SGPT1M); + /* Enable interrupts for this timer */ + writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Enable timer */ + writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE, + u300_timer_base + U300_TIMER_APP_EGPT1); + break; + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + /* Disable interrupts on GP1 */ + writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Disable GP1 */ + writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE, + u300_timer_base + U300_TIMER_APP_DGPT1); + break; + case CLOCK_EVT_MODE_RESUME: + /* Ignore this call */ + break; + } +} + +/* + * The app timer in one shot mode obviously has to be reprogrammed + * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace + * the interrupt disable + timer disable commands with a reset command, + * it will fail miserably. Apparently (and I found this the hard way) + * the timer is very sensitive to the instruction order, though you don't + * get that impression from the data sheet. + */ +static int u300_set_next_event(unsigned long cycles, + struct clock_event_device *evt) + +{ + /* Disable interrupts on GPT1 */ + writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Disable GP1 while we're reprogramming it. */ + writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE, + u300_timer_base + U300_TIMER_APP_DGPT1); + /* Reset the General Purpose timer 1. */ + writel(U300_TIMER_APP_RGPT1_TIMER_RESET, + u300_timer_base + U300_TIMER_APP_RGPT1); + /* IRQ in n * cycles */ + writel(cycles, u300_timer_base + U300_TIMER_APP_GPT1TC); + /* + * We run one shot per tick here! (This is necessary to reconfigure, + * the timer will tilt if you don't!) + */ + writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT, + u300_timer_base + U300_TIMER_APP_SGPT1M); + /* Enable timer interrupts */ + writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE, + u300_timer_base + U300_TIMER_APP_GPT1IE); + /* Then enable the OS timer again */ + writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE, + u300_timer_base + U300_TIMER_APP_EGPT1); + return 0; +} + +static struct u300_clockevent_data u300_clockevent_data = { + /* Use general purpose timer 1 as clock event */ + .cevd = { + .name = "GPT1", + /* Reasonably fast and accurate clock event */ + .rating = 300, + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + .set_next_event = u300_set_next_event, + .set_mode = u300_set_mode, + }, +}; + +/* Clock event timer interrupt handler */ +static irqreturn_t u300_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = &u300_clockevent_data.cevd; + /* ACK/Clear timer IRQ for the APP GPT1 Timer */ + + writel(U300_TIMER_APP_GPT1IA_IRQ_ACK, + u300_timer_base + U300_TIMER_APP_GPT1IA); + evt->event_handler(evt); + return IRQ_HANDLED; +} + +static struct irqaction u300_timer_irq = { + .name = "U300 Timer Tick", + .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .handler = u300_timer_interrupt, +}; + +/* + * Override the global weak sched_clock symbol with this + * local implementation which uses the clocksource to get some + * better resolution when scheduling the kernel. We accept that + * this wraps around for now, since it is just a relative time + * stamp. (Inspired by OMAP implementation.) + */ + +static u64 notrace u300_read_sched_clock(void) +{ + return readl(u300_timer_base + U300_TIMER_APP_GPT2CC); +} + +static unsigned long u300_read_current_timer(void) +{ + return readl(u300_timer_base + U300_TIMER_APP_GPT2CC); +} + +static struct delay_timer u300_delay_timer; + +/* + * This sets up the system timers, clock source and clock event. + */ +static void __init u300_timer_init_of(struct device_node *np) +{ + unsigned int irq; + struct clk *clk; + unsigned long rate; + + u300_timer_base = of_iomap(np, 0); + if (!u300_timer_base) + panic("could not ioremap system timer\n"); + + /* Get the IRQ for the GP1 timer */ + irq = irq_of_parse_and_map(np, 2); + if (!irq) + panic("no IRQ for system timer\n"); + + pr_info("U300 GP1 timer @ base: %p, IRQ: %u\n", u300_timer_base, irq); + + /* Clock the interrupt controller */ + clk = of_clk_get(np, 0); + BUG_ON(IS_ERR(clk)); + clk_prepare_enable(clk); + rate = clk_get_rate(clk); + + u300_clockevent_data.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ); + + sched_clock_register(u300_read_sched_clock, 32, rate); + + u300_delay_timer.read_current_timer = &u300_read_current_timer; + u300_delay_timer.freq = rate; + register_current_timer_delay(&u300_delay_timer); + + /* + * Disable the "OS" and "DD" timers - these are designed for Symbian! + * Example usage in cnh1601578 cpu subsystem pd_timer_app.c + */ + writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE, + u300_timer_base + U300_TIMER_APP_CRC); + writel(U300_TIMER_APP_ROST_TIMER_RESET, + u300_timer_base + U300_TIMER_APP_ROST); + writel(U300_TIMER_APP_DOST_TIMER_DISABLE, + u300_timer_base + U300_TIMER_APP_DOST); + writel(U300_TIMER_APP_RDDT_TIMER_RESET, + u300_timer_base + U300_TIMER_APP_RDDT); + writel(U300_TIMER_APP_DDDT_TIMER_DISABLE, + u300_timer_base + U300_TIMER_APP_DDDT); + + /* Reset the General Purpose timer 1. */ + writel(U300_TIMER_APP_RGPT1_TIMER_RESET, + u300_timer_base + U300_TIMER_APP_RGPT1); + + /* Set up the IRQ handler */ + setup_irq(irq, &u300_timer_irq); + + /* Reset the General Purpose timer 2 */ + writel(U300_TIMER_APP_RGPT2_TIMER_RESET, + u300_timer_base + U300_TIMER_APP_RGPT2); + /* Set this timer to run around forever */ + writel(0xFFFFFFFFU, u300_timer_base + U300_TIMER_APP_GPT2TC); + /* Set continuous mode so it wraps around */ + writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS, + u300_timer_base + U300_TIMER_APP_SGPT2M); + /* Disable timer interrupts */ + writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE, + u300_timer_base + U300_TIMER_APP_GPT2IE); + /* Then enable the GP2 timer to use as a free running us counter */ + writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE, + u300_timer_base + U300_TIMER_APP_EGPT2); + + /* Use general purpose timer 2 as clock source */ + if (clocksource_mmio_init(u300_timer_base + U300_TIMER_APP_GPT2CC, + "GPT2", rate, 300, 32, clocksource_mmio_readl_up)) + pr_err("timer: failed to initialize U300 clock source\n"); + + /* Configure and register the clockevent */ + clockevents_config_and_register(&u300_clockevent_data.cevd, rate, + 1, 0xffffffff); + + /* + * TODO: init and register the rest of the timers too, they can be + * used by hrtimers! + */ +} + +CLOCKSOURCE_OF_DECLARE(u300_timer, "stericsson,u300-apptimer", + u300_timer_init_of); -- cgit v1.1 From ec6c085cc779ae863d363e7d076b763a2a0aca4c Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Thu, 6 Feb 2014 10:40:31 +0100 Subject: clocksource: sunxi: Add new compatibles The Allwinner A10 compatibles were following a slightly different compatible patterns than the rest of the SoCs for historical reasons. Add compatibles matching the other pattern to the timer driver for consistency, and keep the older one for backward compatibility. Signed-off-by: Maxime Ripard Signed-off-by: Daniel Lezcano --- drivers/clocksource/sun4i_timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c index bf497af..efb17c3 100644 --- a/drivers/clocksource/sun4i_timer.c +++ b/drivers/clocksource/sun4i_timer.c @@ -196,5 +196,5 @@ static void __init sun4i_timer_init(struct device_node *node) clockevents_config_and_register(&sun4i_clockevent, rate, TIMER_SYNC_TICKS, 0xffffffff); } -CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-timer", +CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-a10-timer", sun4i_timer_init); -- cgit v1.1 From e6b7f580bacb4a23e1ee5cdf6dc6e54bab141f7c Mon Sep 17 00:00:00 2001 From: Ivan Khoronzhuk Date: Mon, 10 Feb 2014 12:10:56 +0200 Subject: clocksource: timer-keystone: introduce clocksource driver for Keystone Add broadcast clock-event device for the Keystone arch. The timer can be configured as a general-purpose 64-bit timer, dual general-purpose 32-bit timers. When configured as dual 32-bit timers, each half can operate in conjunction (chain mode) or independently (unchained mode) of each other. Reviewed-by: Stephen Boyd Acked-by: Santosh shilimkar Signed-off-by: Ivan Khoronzhuk Signed-off-by: Daniel Lezcano --- drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-keystone.c | 244 +++++++++++++++++++++++++++++++++++ 2 files changed, 245 insertions(+) create mode 100644 drivers/clocksource/timer-keystone.c (limited to 'drivers') diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 01e5435..aed3488 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -38,3 +38,4 @@ obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST) += dummy_timer.o +obj-$(CONFIG_ARCH_KEYSTONE) += timer-keystone.o diff --git a/drivers/clocksource/timer-keystone.c b/drivers/clocksource/timer-keystone.c new file mode 100644 index 0000000..86b08cd --- /dev/null +++ b/drivers/clocksource/timer-keystone.c @@ -0,0 +1,244 @@ +/* + * Keystone broadcast clock-event + * + * Copyright 2013 Texas Instruments, Inc. + * + * Author: Ivan Khoronzhuk + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include + +#define TIMER_NAME "timer-keystone" + +/* Timer register offsets */ +#define TIM12 0x10 +#define TIM34 0x14 +#define PRD12 0x18 +#define PRD34 0x1c +#define TCR 0x20 +#define TGCR 0x24 +#define INTCTLSTAT 0x44 + +/* Timer register bitfields */ +#define TCR_ENAMODE_MASK 0xC0 +#define TCR_ENAMODE_ONESHOT_MASK 0x40 +#define TCR_ENAMODE_PERIODIC_MASK 0x80 + +#define TGCR_TIM_UNRESET_MASK 0x03 +#define INTCTLSTAT_ENINT_MASK 0x01 + +/** + * struct keystone_timer: holds timer's data + * @base: timer memory base address + * @hz_period: cycles per HZ period + * @event_dev: event device based on timer + */ +static struct keystone_timer { + void __iomem *base; + unsigned long hz_period; + struct clock_event_device event_dev; +} timer; + +static inline u32 keystone_timer_readl(unsigned long rg) +{ + return readl_relaxed(timer.base + rg); +} + +static inline void keystone_timer_writel(u32 val, unsigned long rg) +{ + writel_relaxed(val, timer.base + rg); +} + +/** + * keystone_timer_barrier: write memory barrier + * use explicit barrier to avoid using readl/writel non relaxed function + * variants, because in our case non relaxed variants hide the true places + * where barrier is needed. + */ +static inline void keystone_timer_barrier(void) +{ + __iowmb(); +} + +/** + * keystone_timer_config: configures timer to work in oneshot/periodic modes. + * @ mode: mode to configure + * @ period: cycles number to configure for + */ +static int keystone_timer_config(u64 period, enum clock_event_mode mode) +{ + u32 tcr; + u32 off; + + tcr = keystone_timer_readl(TCR); + off = tcr & ~(TCR_ENAMODE_MASK); + + /* set enable mode */ + switch (mode) { + case CLOCK_EVT_MODE_ONESHOT: + tcr |= TCR_ENAMODE_ONESHOT_MASK; + break; + case CLOCK_EVT_MODE_PERIODIC: + tcr |= TCR_ENAMODE_PERIODIC_MASK; + break; + default: + return -1; + } + + /* disable timer */ + keystone_timer_writel(off, TCR); + /* here we have to be sure the timer has been disabled */ + keystone_timer_barrier(); + + /* reset counter to zero, set new period */ + keystone_timer_writel(0, TIM12); + keystone_timer_writel(0, TIM34); + keystone_timer_writel(period & 0xffffffff, PRD12); + keystone_timer_writel(period >> 32, PRD34); + + /* + * enable timer + * here we have to be sure that CNTLO, CNTHI, PRDLO, PRDHI registers + * have been written. + */ + keystone_timer_barrier(); + keystone_timer_writel(tcr, TCR); + return 0; +} + +static void keystone_timer_disable(void) +{ + u32 tcr; + + tcr = keystone_timer_readl(TCR); + + /* disable timer */ + tcr &= ~(TCR_ENAMODE_MASK); + keystone_timer_writel(tcr, TCR); +} + +static irqreturn_t keystone_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + evt->event_handler(evt); + return IRQ_HANDLED; +} + +static int keystone_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + return keystone_timer_config(cycles, evt->mode); +} + +static void keystone_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + keystone_timer_config(timer.hz_period, CLOCK_EVT_MODE_PERIODIC); + break; + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_ONESHOT: + keystone_timer_disable(); + break; + default: + break; + } +} + +static void __init keystone_timer_init(struct device_node *np) +{ + struct clock_event_device *event_dev = &timer.event_dev; + unsigned long rate; + struct clk *clk; + int irq, error; + u32 tgcr; + + irq = irq_of_parse_and_map(np, 0); + if (irq == NO_IRQ) { + pr_err("%s: failed to map interrupts\n", __func__); + return; + } + + timer.base = of_iomap(np, 0); + if (!timer.base) { + pr_err("%s: failed to map registers\n", __func__); + return; + } + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + pr_err("%s: failed to get clock\n", __func__); + iounmap(timer.base); + return; + } + + error = clk_prepare_enable(clk); + if (error) { + pr_err("%s: failed to enable clock\n", __func__); + goto err; + } + + rate = clk_get_rate(clk); + + /* disable, use internal clock source */ + keystone_timer_writel(0, TCR); + /* here we have to be sure the timer has been disabled */ + keystone_timer_barrier(); + + /* reset timer as 64-bit, no pre-scaler, plus features are disabled */ + tgcr = 0; + keystone_timer_writel(0, TGCR); + + /* unreset timer */ + tgcr |= TGCR_TIM_UNRESET_MASK; + keystone_timer_writel(tgcr, TGCR); + + /* init counter to zero */ + keystone_timer_writel(0, TIM12); + keystone_timer_writel(0, TIM34); + + timer.hz_period = DIV_ROUND_UP(rate, HZ); + + /* enable timer interrupts */ + keystone_timer_writel(INTCTLSTAT_ENINT_MASK, INTCTLSTAT); + + error = request_irq(irq, keystone_timer_interrupt, IRQF_TIMER, + TIMER_NAME, event_dev); + if (error) { + pr_err("%s: failed to setup irq\n", __func__); + goto err; + } + + /* setup clockevent */ + event_dev->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + event_dev->set_next_event = keystone_set_next_event; + event_dev->set_mode = keystone_set_mode; + event_dev->cpumask = cpu_all_mask; + event_dev->owner = THIS_MODULE; + event_dev->name = TIMER_NAME; + event_dev->irq = irq; + + clockevents_config_and_register(event_dev, rate, 1, ULONG_MAX); + + pr_info("keystone timer clock @%lu Hz\n", rate); + return; +err: + clk_put(clk); + iounmap(timer.base); +} + +CLOCKSOURCE_OF_DECLARE(keystone_timer, "ti,keystone-timer", + keystone_timer_init); -- cgit v1.1 From e099d01eb221f4a1e713a7663ca143c05303947f Mon Sep 17 00:00:00 2001 From: Matthias Brugger Date: Tue, 18 Feb 2014 19:29:28 +0100 Subject: clocksource: timer-keystone: Delete unnecessary variable Commit 438e0bff5257 added the timer-keystone device driver but make use of an unnecessary variable in the init function. This patch deletes this variable. Signed-off-by: Matthias Brugger Signed-off-by: Daniel Lezcano --- drivers/clocksource/timer-keystone.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/clocksource/timer-keystone.c b/drivers/clocksource/timer-keystone.c index 86b08cd..0250354 100644 --- a/drivers/clocksource/timer-keystone.c +++ b/drivers/clocksource/timer-keystone.c @@ -164,7 +164,6 @@ static void __init keystone_timer_init(struct device_node *np) unsigned long rate; struct clk *clk; int irq, error; - u32 tgcr; irq = irq_of_parse_and_map(np, 0); if (irq == NO_IRQ) { @@ -199,12 +198,10 @@ static void __init keystone_timer_init(struct device_node *np) keystone_timer_barrier(); /* reset timer as 64-bit, no pre-scaler, plus features are disabled */ - tgcr = 0; keystone_timer_writel(0, TGCR); /* unreset timer */ - tgcr |= TGCR_TIM_UNRESET_MASK; - keystone_timer_writel(tgcr, TGCR); + keystone_timer_writel(TGCR_TIM_UNRESET_MASK, TGCR); /* init counter to zero */ keystone_timer_writel(0, TIM12); -- cgit v1.1 From 0a54a069585bb875d37494c434f36a19bcc05df9 Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Wed, 19 Feb 2014 17:05:25 -0300 Subject: clocksource: orion: Use atomic access for shared registers Replace the driver-specific thread-safe shared register API by the recently introduced atomic_io_clear_set(). Cc: Daniel Lezcano Tested-by: Sebastian Hesselbarth Tested-by: Willy Tarreau Acked-by: Jason Cooper Signed-off-by: Ezequiel Garcia Signed-off-by: Daniel Lezcano --- drivers/clocksource/time-orion.c | 28 ++++++++++------------------ 1 file changed, 10 insertions(+), 18 deletions(-) (limited to 'drivers') diff --git a/drivers/clocksource/time-orion.c b/drivers/clocksource/time-orion.c index 2006622..0b3ce03 100644 --- a/drivers/clocksource/time-orion.c +++ b/drivers/clocksource/time-orion.c @@ -35,20 +35,6 @@ #define ORION_ONESHOT_MAX 0xfffffffe static void __iomem *timer_base; -static DEFINE_SPINLOCK(timer_ctrl_lock); - -/* - * Thread-safe access to TIMER_CTRL register - * (shared with watchdog timer) - */ -void orion_timer_ctrl_clrset(u32 clr, u32 set) -{ - spin_lock(&timer_ctrl_lock); - writel((readl(timer_base + TIMER_CTRL) & ~clr) | set, - timer_base + TIMER_CTRL); - spin_unlock(&timer_ctrl_lock); -} -EXPORT_SYMBOL(orion_timer_ctrl_clrset); /* * Free-running clocksource handling. @@ -68,7 +54,8 @@ static int orion_clkevt_next_event(unsigned long delta, { /* setup and enable one-shot timer */ writel(delta, timer_base + TIMER1_VAL); - orion_timer_ctrl_clrset(TIMER1_RELOAD_EN, TIMER1_EN); + atomic_io_modify(timer_base + TIMER_CTRL, + TIMER1_RELOAD_EN | TIMER1_EN, TIMER1_EN); return 0; } @@ -80,10 +67,13 @@ static void orion_clkevt_mode(enum clock_event_mode mode, /* setup and enable periodic timer at 1/HZ intervals */ writel(ticks_per_jiffy - 1, timer_base + TIMER1_RELOAD); writel(ticks_per_jiffy - 1, timer_base + TIMER1_VAL); - orion_timer_ctrl_clrset(0, TIMER1_RELOAD_EN | TIMER1_EN); + atomic_io_modify(timer_base + TIMER_CTRL, + TIMER1_RELOAD_EN | TIMER1_EN, + TIMER1_RELOAD_EN | TIMER1_EN); } else { /* disable timer */ - orion_timer_ctrl_clrset(TIMER1_RELOAD_EN | TIMER1_EN, 0); + atomic_io_modify(timer_base + TIMER_CTRL, + TIMER1_RELOAD_EN | TIMER1_EN, 0); } } @@ -131,7 +121,9 @@ static void __init orion_timer_init(struct device_node *np) /* setup timer0 as free-running clocksource */ writel(~0, timer_base + TIMER0_VAL); writel(~0, timer_base + TIMER0_RELOAD); - orion_timer_ctrl_clrset(0, TIMER0_RELOAD_EN | TIMER0_EN); + atomic_io_modify(timer_base + TIMER_CTRL, + TIMER0_RELOAD_EN | TIMER0_EN, + TIMER0_RELOAD_EN | TIMER0_EN); clocksource_mmio_init(timer_base + TIMER0_VAL, "orion_clocksource", clk_get_rate(clk), 300, 32, clocksource_mmio_readl_down); -- cgit v1.1 From c8af34b4dbc211f1e08a7ea513dc399046825866 Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Wed, 19 Feb 2014 17:05:26 -0300 Subject: clocksource: armada-370-xp: Use atomic access for shared registers Replace the driver-specific thread-safe shared register API by the recently introduced atomic_io_clear_set(). Signed-off-by: Ezequiel Garcia Signed-off-by: Daniel Lezcano --- drivers/clocksource/time-armada-370-xp.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) (limited to 'drivers') diff --git a/drivers/clocksource/time-armada-370-xp.c b/drivers/clocksource/time-armada-370-xp.c index ee8691b..0451e62 100644 --- a/drivers/clocksource/time-armada-370-xp.c +++ b/drivers/clocksource/time-armada-370-xp.c @@ -85,12 +85,6 @@ static u32 ticks_per_jiffy; static struct clock_event_device __percpu *armada_370_xp_evt; -static void timer_ctrl_clrset(u32 clr, u32 set) -{ - writel((readl(timer_base + TIMER_CTRL_OFF) & ~clr) | set, - timer_base + TIMER_CTRL_OFF); -} - static void local_timer_ctrl_clrset(u32 clr, u32 set) { writel((readl(local_base + TIMER_CTRL_OFF) & ~clr) | set, @@ -245,7 +239,7 @@ static void __init armada_370_xp_timer_common_init(struct device_node *np) clr = TIMER0_25MHZ; enable_mask = TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT); } - timer_ctrl_clrset(clr, set); + atomic_io_modify(timer_base + TIMER_CTRL_OFF, clr | set, set); local_timer_ctrl_clrset(clr, set); /* @@ -263,7 +257,9 @@ static void __init armada_370_xp_timer_common_init(struct device_node *np) writel(0xffffffff, timer_base + TIMER0_VAL_OFF); writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF); - timer_ctrl_clrset(0, TIMER0_RELOAD_EN | enable_mask); + atomic_io_modify(timer_base + TIMER_CTRL_OFF, + TIMER0_RELOAD_EN | enable_mask, + TIMER0_RELOAD_EN | enable_mask); /* * Set scale and timer for sched_clock. -- cgit v1.1 From fd3f1270d237d1afb344ee6bfd0e50c488c29e34 Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Thu, 20 Feb 2014 12:54:45 +0100 Subject: clocksource: Add Kconfig entries for CMT, MTU2, TMU and STI Add Kconfig entries for CMT, MTU2, TMU and STI to drivers/clocksource/Kconfig. This will allow us to get rid of duplicated entires in architecture code such as arch/sh and arch/arm/mach-shmobile. Signed-off-by: Magnus Damm Signed-off-by: Wolfram Sang Signed-off-by: Daniel Lezcano --- drivers/clocksource/Kconfig | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'drivers') diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index cd6950f..4f754a9 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -140,3 +140,47 @@ config VF_PIT_TIMER bool help Support for Period Interrupt Timer on Freescale Vybrid Family SoCs. + +config SYS_SUPPORTS_SH_CMT + bool + +config SYS_SUPPORTS_SH_MTU2 + bool + +config SYS_SUPPORTS_SH_TMU + bool + +config SYS_SUPPORTS_EM_STI + bool + +config SH_TIMER_CMT + bool "Renesas CMT timer driver" if COMPILE_TEST + default SYS_SUPPORTS_SH_CMT + help + This enables build of a clocksource and clockevent driver for + the Compare Match Timer (CMT) hardware available in 16/32/48-bit + variants on a wide range of Mobile and Automotive SoCs from Renesas. + +config SH_TIMER_MTU2 + bool "Renesas MTU2 timer driver" if COMPILE_TEST + default SYS_SUPPORTS_SH_MTU2 + help + This enables build of a clockevent driver for the Multi-Function + Timer Pulse Unit 2 (TMU2) hardware available on SoCs from Renesas. + This hardware comes with 16 bit-timer registers. + +config SH_TIMER_TMU + bool "Renesas TMU timer driver" if COMPILE_TEST + default SYS_SUPPORTS_SH_TMU + help + This enables build of a clocksource and clockevent driver for + the 32-bit Timer Unit (TMU) hardware available on a wide range + SoCs from Renesas. + +config EM_TIMER_STI + bool "Renesas STI timer driver" if COMPILE_TEST + default SYS_SUPPORTS_EM_STI + help + This enables build of a clocksource and clockevent driver for + the 48-bit System Timer (STI) hardware available on a SoCs + such as EMEV2 from former NEC Electronics. -- cgit v1.1 From 5f0ba3b462b2d36b3c28748863747fb1050f40d0 Mon Sep 17 00:00:00 2001 From: Soren Brinkmann Date: Wed, 19 Feb 2014 15:14:41 -0800 Subject: clocksource/cadence_ttc: Call clockevents_update_freq() with IRQs enabled The timer core takes care of serialization and IRQs. Hence the driver is no longer required to disable interrupts when calling clockevents_update_freq(). Signed-off-by: Soren Brinkmann Signed-off-by: Daniel Lezcano Acked-by: Michal Simek --- drivers/clocksource/cadence_ttc_timer.c | 17 ++--------------- 1 file changed, 2 insertions(+), 15 deletions(-) (limited to 'drivers') diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c index 63f176d..f05b9fd 100644 --- a/drivers/clocksource/cadence_ttc_timer.c +++ b/drivers/clocksource/cadence_ttc_timer.c @@ -321,25 +321,12 @@ static int ttc_rate_change_clockevent_cb(struct notifier_block *nb, switch (event) { case POST_RATE_CHANGE: - { - unsigned long flags; - - /* - * clockevents_update_freq should be called with IRQ disabled on - * the CPU the timer provides events for. The timer we use is - * common to both CPUs, not sure if we need to run on both - * cores. - */ - local_irq_save(flags); - clockevents_update_freq(&ttcce->ce, - ndata->new_rate / PRESCALE); - local_irq_restore(flags); - /* update cached frequency */ ttc->freq = ndata->new_rate; + clockevents_update_freq(&ttcce->ce, ndata->new_rate / PRESCALE); + /* fall through */ - } case PRE_RATE_CHANGE: case ABORT_RATE_CHANGE: default: -- cgit v1.1 From b3e90722f6f53fa457a88146a877e34ea71d25ea Mon Sep 17 00:00:00 2001 From: Soren Brinkmann Date: Wed, 19 Feb 2014 15:14:42 -0800 Subject: clocksource/cadence_ttc: Overhaul clocksource frequency adjustment The currently used method adjusting the clocksource to a changing input frequency does not work on kernels from 3.11 on. The new approach is to keep the timer frequency as constant as possible. I.e. - due to the TTC's prescaler limitations, allow frequency changes only if the frequency scales by a power of 2 - adjust the counter's divider on the fly when a frequency change occurs This limits cpufreq to scale by certain factors only. But we may keep the time base somewhat constant, so that sleep() & co keep working as expected, while supporting cpufreq. Signed-off-by: Soren Brinkmann Signed-off-by: Daniel Lezcano Acked-by: Michal Simek --- drivers/clocksource/cadence_ttc_timer.c | 104 ++++++++++++++++++++++++++------ 1 file changed, 84 insertions(+), 20 deletions(-) (limited to 'drivers') diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c index f05b9fd..49fbe28 100644 --- a/drivers/clocksource/cadence_ttc_timer.c +++ b/drivers/clocksource/cadence_ttc_timer.c @@ -16,6 +16,7 @@ */ #include +#include #include #include #include @@ -52,6 +53,8 @@ #define TTC_CNT_CNTRL_DISABLE_MASK 0x1 #define TTC_CLK_CNTRL_CSRC_MASK (1 << 5) /* clock source */ +#define TTC_CLK_CNTRL_PSV_MASK 0x1e +#define TTC_CLK_CNTRL_PSV_SHIFT 1 /* * Setup the timers to use pre-scaling, using a fixed value for now that will @@ -63,6 +66,8 @@ #define CLK_CNTRL_PRESCALE_EN 1 #define CNT_CNTRL_RESET (1 << 4) +#define MAX_F_ERR 50 + /** * struct ttc_timer - This definition defines local timer structure * @@ -82,6 +87,8 @@ struct ttc_timer { container_of(x, struct ttc_timer, clk_rate_change_nb) struct ttc_timer_clocksource { + u32 scale_clk_ctrl_reg_old; + u32 scale_clk_ctrl_reg_new; struct ttc_timer ttc; struct clocksource cs; }; @@ -229,32 +236,89 @@ static int ttc_rate_change_clocksource_cb(struct notifier_block *nb, struct ttc_timer_clocksource, ttc); switch (event) { - case POST_RATE_CHANGE: + case PRE_RATE_CHANGE: + { + u32 psv; + unsigned long factor, rate_low, rate_high; + + if (ndata->new_rate > ndata->old_rate) { + factor = DIV_ROUND_CLOSEST(ndata->new_rate, + ndata->old_rate); + rate_low = ndata->old_rate; + rate_high = ndata->new_rate; + } else { + factor = DIV_ROUND_CLOSEST(ndata->old_rate, + ndata->new_rate); + rate_low = ndata->new_rate; + rate_high = ndata->old_rate; + } + + if (!is_power_of_2(factor)) + return NOTIFY_BAD; + + if (abs(rate_high - (factor * rate_low)) > MAX_F_ERR) + return NOTIFY_BAD; + + factor = __ilog2_u32(factor); + /* - * Do whatever is necessary to maintain a proper time base - * - * I cannot find a way to adjust the currently used clocksource - * to the new frequency. __clocksource_updatefreq_hz() sounds - * good, but does not work. Not sure what's that missing. - * - * This approach works, but triggers two clocksource switches. - * The first after unregister to clocksource jiffies. And - * another one after the register to the newly registered timer. - * - * Alternatively we could 'waste' another HW timer to ping pong - * between clock sources. That would also use one register and - * one unregister call, but only trigger one clocksource switch - * for the cost of another HW timer used by the OS. + * store timer clock ctrl register so we can restore it in case + * of an abort. */ - clocksource_unregister(&ttccs->cs); - clocksource_register_hz(&ttccs->cs, - ndata->new_rate / PRESCALE); - /* fall through */ - case PRE_RATE_CHANGE: + ttccs->scale_clk_ctrl_reg_old = + __raw_readl(ttccs->ttc.base_addr + + TTC_CLK_CNTRL_OFFSET); + + psv = (ttccs->scale_clk_ctrl_reg_old & + TTC_CLK_CNTRL_PSV_MASK) >> + TTC_CLK_CNTRL_PSV_SHIFT; + if (ndata->new_rate < ndata->old_rate) + psv -= factor; + else + psv += factor; + + /* prescaler within legal range? */ + if (psv & ~(TTC_CLK_CNTRL_PSV_MASK >> TTC_CLK_CNTRL_PSV_SHIFT)) + return NOTIFY_BAD; + + ttccs->scale_clk_ctrl_reg_new = ttccs->scale_clk_ctrl_reg_old & + ~TTC_CLK_CNTRL_PSV_MASK; + ttccs->scale_clk_ctrl_reg_new |= psv << TTC_CLK_CNTRL_PSV_SHIFT; + + + /* scale down: adjust divider in post-change notification */ + if (ndata->new_rate < ndata->old_rate) + return NOTIFY_DONE; + + /* scale up: adjust divider now - before frequency change */ + __raw_writel(ttccs->scale_clk_ctrl_reg_new, + ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET); + break; + } + case POST_RATE_CHANGE: + /* scale up: pre-change notification did the adjustment */ + if (ndata->new_rate > ndata->old_rate) + return NOTIFY_OK; + + /* scale down: adjust divider now - after frequency change */ + __raw_writel(ttccs->scale_clk_ctrl_reg_new, + ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET); + break; + case ABORT_RATE_CHANGE: + /* we have to undo the adjustment in case we scale up */ + if (ndata->new_rate < ndata->old_rate) + return NOTIFY_OK; + + /* restore original register value */ + __raw_writel(ttccs->scale_clk_ctrl_reg_old, + ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET); + /* fall through */ default: return NOTIFY_DONE; } + + return NOTIFY_DONE; } static void __init ttc_setup_clocksource(struct clk *clk, void __iomem *base) -- cgit v1.1 From 09e15176ded1faa7bd685b3b5b1213cf0240566e Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Sat, 1 Mar 2014 16:57:14 +0300 Subject: clocksource: exynos_mct: silence a static checker warning My guess is we aren't going to have a 2 digit cpuid here any time soon but the static checkers don't know that and complain that the snprintf() could overflow. Signed-off-by: Dan Carpenter Signed-off-by: Daniel Lezcano --- drivers/clocksource/exynos_mct.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c index 48f76bc..c2e390e 100644 --- a/drivers/clocksource/exynos_mct.c +++ b/drivers/clocksource/exynos_mct.c @@ -410,7 +410,7 @@ static int exynos4_local_timer_setup(struct clock_event_device *evt) mevt = container_of(evt, struct mct_clock_event_device, evt); mevt->base = EXYNOS4_MCT_L_BASE(cpu); - sprintf(mevt->name, "mct_tick%d", cpu); + snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu); evt->name = mevt->name; evt->cpumask = cpumask_of(cpu); -- cgit v1.1 From 87291a9267ecc0a8efceb4d9cbd4da870f958fc1 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Thu, 20 Mar 2014 15:05:50 +0100 Subject: clocksource: CMT, MTU2, TMU and STI should depend on GENERIC_CLOCKEVENTS If GENERIC_CLOCKEVENTS=n: drivers/clocksource/sh_cmt.c:54:28: error: field 'ced' has incomplete type drivers/clocksource/sh_cmt.c: In function 'sh_cmt_interrupt': drivers/clocksource/sh_cmt.c:407:23: error: 'CLOCK_EVT_MODE_ONESHOT' undeclared (first use in this function) drivers/clocksource/sh_mtu2.c:44:28: error: field 'ced' has incomplete type drivers/clocksource/sh_mtu2.c: In function 'ced_to_sh_mtu2': drivers/clocksource/sh_mtu2.c:184:70: warning: initialization from incompatible pointer type [enabled by default] drivers/clocksource/sh_mtu2.c: At top level: drivers/clocksource/sh_mtu2.c:188:16: warning: 'enum clock_event_mode' declared inside parameter list [enabled by default] drivers/clocksource/sh_tmu.c:45:28: error: field 'ced' has incomplete type drivers/clocksource/sh_tmu.c: In function 'sh_tmu_interrupt': drivers/clocksource/sh_tmu.c:207:21: error: 'CLOCK_EVT_MODE_ONESHOT' undeclared (first use in this function) drivers/clocksource/em_sti.c:44:28: error: field 'ced' has incomplete type drivers/clocksource/em_sti.c: In function 'ced_to_em_sti': drivers/clocksource/em_sti.c:251:69: warning: initialization from incompatible pointer type [enabled by default] drivers/clocksource/em_sti.c: At top level: drivers/clocksource/em_sti.c:255:16: warning: 'enum clock_event_mode' declared inside parameter list [enabled by default] Signed-off-by: Geert Uytterhoeven Cc: Magnus Damm Cc: Daniel Lezcano Link: http://lkml.kernel.org/r/1395324352-9146-1-git-send-email-geert@linux-m68k.org Signed-off-by: Thomas Gleixner --- drivers/clocksource/Kconfig | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers') diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 4f754a9..52e9329 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -155,6 +155,7 @@ config SYS_SUPPORTS_EM_STI config SH_TIMER_CMT bool "Renesas CMT timer driver" if COMPILE_TEST + depends on GENERIC_CLOCKEVENTS default SYS_SUPPORTS_SH_CMT help This enables build of a clocksource and clockevent driver for @@ -163,6 +164,7 @@ config SH_TIMER_CMT config SH_TIMER_MTU2 bool "Renesas MTU2 timer driver" if COMPILE_TEST + depends on GENERIC_CLOCKEVENTS default SYS_SUPPORTS_SH_MTU2 help This enables build of a clockevent driver for the Multi-Function @@ -171,6 +173,7 @@ config SH_TIMER_MTU2 config SH_TIMER_TMU bool "Renesas TMU timer driver" if COMPILE_TEST + depends on GENERIC_CLOCKEVENTS default SYS_SUPPORTS_SH_TMU help This enables build of a clocksource and clockevent driver for @@ -179,6 +182,7 @@ config SH_TIMER_TMU config EM_TIMER_STI bool "Renesas STI timer driver" if COMPILE_TEST + depends on GENERIC_CLOCKEVENTS default SYS_SUPPORTS_EM_STI help This enables build of a clocksource and clockevent driver for -- cgit v1.1