diff options
Diffstat (limited to 'drivers/clocksource/timer-sun5i.c')
-rw-r--r-- | drivers/clocksource/timer-sun5i.c | 299 |
1 files changed, 228 insertions, 71 deletions
diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c index 58597fbcc046..28aa4b7bb602 100644 --- a/drivers/clocksource/timer-sun5i.c +++ b/drivers/clocksource/timer-sun5i.c @@ -17,6 +17,7 @@ #include <linux/irq.h> #include <linux/irqreturn.h> #include <linux/reset.h> +#include <linux/slab.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> @@ -36,8 +37,31 @@ #define TIMER_SYNC_TICKS 3 -static void __iomem *timer_base; -static u32 ticks_per_jiffy; +struct sun5i_timer { + void __iomem *base; + struct clk *clk; + struct notifier_block clk_rate_cb; + u32 ticks_per_jiffy; +}; + +#define to_sun5i_timer(x) \ + container_of(x, struct sun5i_timer, clk_rate_cb) + +struct sun5i_timer_clksrc { + struct sun5i_timer timer; + struct clocksource clksrc; +}; + +#define to_sun5i_timer_clksrc(x) \ + container_of(x, struct sun5i_timer_clksrc, clksrc) + +struct sun5i_timer_clkevt { + struct sun5i_timer timer; + struct clock_event_device clkevt; +}; + +#define to_sun5i_timer_clkevt(x) \ + container_of(x, struct sun5i_timer_clkevt, clkevt) /* * When we disable a timer, we need to wait at least for 2 cycles of @@ -45,30 +69,30 @@ static u32 ticks_per_jiffy; * that is already setup and runs at the same frequency than the other * timers, and we never will be disabled. */ -static void sun5i_clkevt_sync(void) +static void sun5i_clkevt_sync(struct sun5i_timer_clkevt *ce) { - u32 old = readl(timer_base + TIMER_CNTVAL_LO_REG(1)); + u32 old = readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1)); - while ((old - readl(timer_base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS) + while ((old - readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS) cpu_relax(); } -static void sun5i_clkevt_time_stop(u8 timer) +static void sun5i_clkevt_time_stop(struct sun5i_timer_clkevt *ce, u8 timer) { - u32 val = readl(timer_base + TIMER_CTL_REG(timer)); - writel(val & ~TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(timer)); + u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer)); + writel(val & ~TIMER_CTL_ENABLE, ce->timer.base + TIMER_CTL_REG(timer)); - sun5i_clkevt_sync(); + sun5i_clkevt_sync(ce); } -static void sun5i_clkevt_time_setup(u8 timer, u32 delay) +static void sun5i_clkevt_time_setup(struct sun5i_timer_clkevt *ce, u8 timer, u32 delay) { - writel(delay, timer_base + TIMER_INTVAL_LO_REG(timer)); + writel(delay, ce->timer.base + TIMER_INTVAL_LO_REG(timer)); } -static void sun5i_clkevt_time_start(u8 timer, bool periodic) +static void sun5i_clkevt_time_start(struct sun5i_timer_clkevt *ce, u8 timer, bool periodic) { - u32 val = readl(timer_base + TIMER_CTL_REG(timer)); + u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer)); if (periodic) val &= ~TIMER_CTL_ONESHOT; @@ -76,75 +100,230 @@ static void sun5i_clkevt_time_start(u8 timer, bool periodic) val |= TIMER_CTL_ONESHOT; writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD, - timer_base + TIMER_CTL_REG(timer)); + ce->timer.base + TIMER_CTL_REG(timer)); } static void sun5i_clkevt_mode(enum clock_event_mode mode, - struct clock_event_device *clk) + struct clock_event_device *clkevt) { + struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt); + switch (mode) { case CLOCK_EVT_MODE_PERIODIC: - sun5i_clkevt_time_stop(0); - sun5i_clkevt_time_setup(0, ticks_per_jiffy); - sun5i_clkevt_time_start(0, true); + sun5i_clkevt_time_stop(ce, 0); + sun5i_clkevt_time_setup(ce, 0, ce->timer.ticks_per_jiffy); + sun5i_clkevt_time_start(ce, 0, true); break; case CLOCK_EVT_MODE_ONESHOT: - sun5i_clkevt_time_stop(0); - sun5i_clkevt_time_start(0, false); + sun5i_clkevt_time_stop(ce, 0); + sun5i_clkevt_time_start(ce, 0, false); break; case CLOCK_EVT_MODE_UNUSED: case CLOCK_EVT_MODE_SHUTDOWN: default: - sun5i_clkevt_time_stop(0); + sun5i_clkevt_time_stop(ce, 0); break; } } static int sun5i_clkevt_next_event(unsigned long evt, - struct clock_event_device *unused) + struct clock_event_device *clkevt) { - sun5i_clkevt_time_stop(0); - sun5i_clkevt_time_setup(0, evt - TIMER_SYNC_TICKS); - sun5i_clkevt_time_start(0, false); + struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt); + + sun5i_clkevt_time_stop(ce, 0); + sun5i_clkevt_time_setup(ce, 0, evt - TIMER_SYNC_TICKS); + sun5i_clkevt_time_start(ce, 0, false); return 0; } -static struct clock_event_device sun5i_clockevent = { - .name = "sun5i_tick", - .rating = 340, - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .set_mode = sun5i_clkevt_mode, - .set_next_event = sun5i_clkevt_next_event, -}; - - static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id) { - struct clock_event_device *evt = (struct clock_event_device *)dev_id; + struct sun5i_timer_clkevt *ce = (struct sun5i_timer_clkevt *)dev_id; - writel(0x1, timer_base + TIMER_IRQ_ST_REG); - evt->event_handler(evt); + writel(0x1, ce->timer.base + TIMER_IRQ_ST_REG); + ce->clkevt.event_handler(&ce->clkevt); return IRQ_HANDLED; } -static struct irqaction sun5i_timer_irq = { - .name = "sun5i_timer0", - .flags = IRQF_TIMER | IRQF_IRQPOLL, - .handler = sun5i_timer_interrupt, - .dev_id = &sun5i_clockevent, -}; +static cycle_t sun5i_clksrc_read(struct clocksource *clksrc) +{ + struct sun5i_timer_clksrc *cs = to_sun5i_timer_clksrc(clksrc); + + return ~readl(cs->timer.base + TIMER_CNTVAL_LO_REG(1)); +} + +static int sun5i_rate_cb_clksrc(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct clk_notifier_data *ndata = data; + struct sun5i_timer *timer = to_sun5i_timer(nb); + struct sun5i_timer_clksrc *cs = container_of(timer, struct sun5i_timer_clksrc, timer); + + switch (event) { + case PRE_RATE_CHANGE: + clocksource_unregister(&cs->clksrc); + break; + + case POST_RATE_CHANGE: + clocksource_register_hz(&cs->clksrc, ndata->new_rate); + break; + + default: + break; + } + + return NOTIFY_DONE; +} + +static int __init sun5i_setup_clocksource(struct device_node *node, + void __iomem *base, + struct clk *clk, int irq) +{ + struct sun5i_timer_clksrc *cs; + unsigned long rate; + int ret; + + cs = kzalloc(sizeof(*cs), GFP_KERNEL); + if (!cs) + return -ENOMEM; + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("Couldn't enable parent clock\n"); + goto err_free; + } + + rate = clk_get_rate(clk); + + cs->timer.base = base; + cs->timer.clk = clk; + cs->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clksrc; + cs->timer.clk_rate_cb.next = NULL; + + ret = clk_notifier_register(clk, &cs->timer.clk_rate_cb); + if (ret) { + pr_err("Unable to register clock notifier.\n"); + goto err_disable_clk; + } + + writel(~0, base + TIMER_INTVAL_LO_REG(1)); + writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD, + base + TIMER_CTL_REG(1)); + + cs->clksrc.name = node->name; + cs->clksrc.rating = 340; + cs->clksrc.read = sun5i_clksrc_read; + cs->clksrc.mask = CLOCKSOURCE_MASK(32); + cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; + + ret = clocksource_register_hz(&cs->clksrc, rate); + if (ret) { + pr_err("Couldn't register clock source.\n"); + goto err_remove_notifier; + } + + return 0; + +err_remove_notifier: + clk_notifier_unregister(clk, &cs->timer.clk_rate_cb); +err_disable_clk: + clk_disable_unprepare(clk); +err_free: + kfree(cs); + return ret; +} + +static int sun5i_rate_cb_clkevt(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct clk_notifier_data *ndata = data; + struct sun5i_timer *timer = to_sun5i_timer(nb); + struct sun5i_timer_clkevt *ce = container_of(timer, struct sun5i_timer_clkevt, timer); + + if (event == POST_RATE_CHANGE) { + clockevents_update_freq(&ce->clkevt, ndata->new_rate); + ce->timer.ticks_per_jiffy = DIV_ROUND_UP(ndata->new_rate, HZ); + } + + return NOTIFY_DONE; +} + +static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem *base, + struct clk *clk, int irq) +{ + struct sun5i_timer_clkevt *ce; + unsigned long rate; + int ret; + u32 val; + + ce = kzalloc(sizeof(*ce), GFP_KERNEL); + if (!ce) + return -ENOMEM; + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("Couldn't enable parent clock\n"); + goto err_free; + } + + rate = clk_get_rate(clk); + + ce->timer.base = base; + ce->timer.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ); + ce->timer.clk = clk; + ce->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clkevt; + ce->timer.clk_rate_cb.next = NULL; + + ret = clk_notifier_register(clk, &ce->timer.clk_rate_cb); + if (ret) { + pr_err("Unable to register clock notifier.\n"); + goto err_disable_clk; + } + + ce->clkevt.name = node->name; + ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + ce->clkevt.set_next_event = sun5i_clkevt_next_event; + ce->clkevt.set_mode = sun5i_clkevt_mode; + ce->clkevt.rating = 340; + ce->clkevt.irq = irq; + ce->clkevt.cpumask = cpu_possible_mask; + + /* Enable timer0 interrupt */ + val = readl(base + TIMER_IRQ_EN_REG); + writel(val | TIMER_IRQ_EN(0), base + TIMER_IRQ_EN_REG); + + clockevents_config_and_register(&ce->clkevt, rate, + TIMER_SYNC_TICKS, 0xffffffff); + + ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL, + "sun5i_timer0", ce); + if (ret) { + pr_err("Unable to register interrupt\n"); + goto err_remove_notifier; + } + + return 0; + +err_remove_notifier: + clk_notifier_unregister(clk, &ce->timer.clk_rate_cb); +err_disable_clk: + clk_disable_unprepare(clk); +err_free: + kfree(ce); + return ret; +} static void __init sun5i_timer_init(struct device_node *node) { struct reset_control *rstc; - unsigned long rate; + void __iomem *timer_base; struct clk *clk; - int ret, irq; - u32 val; + int irq; - timer_base = of_iomap(node, 0); + timer_base = of_io_request_and_map(node, 0, of_node_full_name(node)); if (!timer_base) panic("Can't map registers"); @@ -155,35 +334,13 @@ static void __init sun5i_timer_init(struct device_node *node) clk = of_clk_get(node, 0); if (IS_ERR(clk)) panic("Can't get timer clock"); - clk_prepare_enable(clk); - rate = clk_get_rate(clk); rstc = of_reset_control_get(node, NULL); if (!IS_ERR(rstc)) reset_control_deassert(rstc); - writel(~0, timer_base + TIMER_INTVAL_LO_REG(1)); - writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD, - timer_base + TIMER_CTL_REG(1)); - - clocksource_mmio_init(timer_base + TIMER_CNTVAL_LO_REG(1), node->name, - rate, 340, 32, clocksource_mmio_readl_down); - - ticks_per_jiffy = DIV_ROUND_UP(rate, HZ); - - /* Enable timer0 interrupt */ - val = readl(timer_base + TIMER_IRQ_EN_REG); - writel(val | TIMER_IRQ_EN(0), timer_base + TIMER_IRQ_EN_REG); - - sun5i_clockevent.cpumask = cpu_possible_mask; - sun5i_clockevent.irq = irq; - - clockevents_config_and_register(&sun5i_clockevent, rate, - TIMER_SYNC_TICKS, 0xffffffff); - - ret = setup_irq(irq, &sun5i_timer_irq); - if (ret) - pr_warn("failed to setup irq %d\n", irq); + sun5i_setup_clocksource(node, timer_base, clk, irq); + sun5i_setup_clockevent(node, timer_base, clk, irq); } CLOCKSOURCE_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer", sun5i_timer_init); |