diff options
Diffstat (limited to 'drivers/clocksource/timer-microchip-pit64b.c')
| -rw-r--r-- | drivers/clocksource/timer-microchip-pit64b.c | 164 |
1 files changed, 110 insertions, 54 deletions
diff --git a/drivers/clocksource/timer-microchip-pit64b.c b/drivers/clocksource/timer-microchip-pit64b.c index 59e11ca8ee73..57209bb38c70 100644 --- a/drivers/clocksource/timer-microchip-pit64b.c +++ b/drivers/clocksource/timer-microchip-pit64b.c @@ -9,6 +9,7 @@ #include <linux/clk.h> #include <linux/clockchips.h> +#include <linux/delay.h> #include <linux/interrupt.h> #include <linux/of_address.h> #include <linux/of_irq.h> @@ -42,8 +43,7 @@ #define MCHP_PIT64B_LSBMASK GENMASK_ULL(31, 0) #define MCHP_PIT64B_PRES_TO_MODE(p) (MCHP_PIT64B_MR_PRES & ((p) << 8)) #define MCHP_PIT64B_MODE_TO_PRES(m) ((MCHP_PIT64B_MR_PRES & (m)) >> 8) -#define MCHP_PIT64B_DEF_CS_FREQ 5000000UL /* 5 MHz */ -#define MCHP_PIT64B_DEF_CE_FREQ 32768 /* 32 KHz */ +#define MCHP_PIT64B_DEF_FREQ 5000000UL /* 5 MHz */ #define MCHP_PIT64B_NAME "pit64b" @@ -62,7 +62,7 @@ struct mchp_pit64b_timer { }; /** - * mchp_pit64b_clkevt - PIT64B clockevent data structure + * struct mchp_pit64b_clkevt - PIT64B clockevent data structure * @timer: PIT64B timer * @clkevt: clockevent */ @@ -71,14 +71,30 @@ struct mchp_pit64b_clkevt { struct clock_event_device clkevt; }; -#define to_mchp_pit64b_timer(x) \ +#define clkevt_to_mchp_pit64b_timer(x) \ ((struct mchp_pit64b_timer *)container_of(x,\ struct mchp_pit64b_clkevt, clkevt)) +/** + * struct mchp_pit64b_clksrc - PIT64B clocksource data structure + * @timer: PIT64B timer + * @clksrc: clocksource + */ +struct mchp_pit64b_clksrc { + struct mchp_pit64b_timer timer; + struct clocksource clksrc; +}; + +#define clksrc_to_mchp_pit64b_timer(x) \ + ((struct mchp_pit64b_timer *)container_of(x,\ + struct mchp_pit64b_clksrc, clksrc)) + /* Base address for clocksource timer. */ static void __iomem *mchp_pit64b_cs_base; /* Default cycles for clockevent timer. */ static u64 mchp_pit64b_ce_cycles; +/* Delay timer. */ +static struct delay_timer mchp_pit64b_dt; static inline u64 mchp_pit64b_cnt_read(void __iomem *base) { @@ -116,28 +132,67 @@ static inline void mchp_pit64b_reset(struct mchp_pit64b_timer *timer, writel_relaxed(MCHP_PIT64B_CR_START, timer->base + MCHP_PIT64B_CR); } +static void mchp_pit64b_suspend(struct mchp_pit64b_timer *timer) +{ + writel_relaxed(MCHP_PIT64B_CR_SWRST, timer->base + MCHP_PIT64B_CR); + if (timer->mode & MCHP_PIT64B_MR_SGCLK) + clk_disable_unprepare(timer->gclk); + clk_disable_unprepare(timer->pclk); +} + +static void mchp_pit64b_resume(struct mchp_pit64b_timer *timer) +{ + clk_prepare_enable(timer->pclk); + if (timer->mode & MCHP_PIT64B_MR_SGCLK) + clk_prepare_enable(timer->gclk); +} + +static void mchp_pit64b_clksrc_suspend(struct clocksource *cs) +{ + struct mchp_pit64b_timer *timer = clksrc_to_mchp_pit64b_timer(cs); + + mchp_pit64b_suspend(timer); +} + +static void mchp_pit64b_clksrc_resume(struct clocksource *cs) +{ + struct mchp_pit64b_timer *timer = clksrc_to_mchp_pit64b_timer(cs); + + mchp_pit64b_resume(timer); + mchp_pit64b_reset(timer, ULLONG_MAX, MCHP_PIT64B_MR_CONT, 0); +} + static u64 mchp_pit64b_clksrc_read(struct clocksource *cs) { return mchp_pit64b_cnt_read(mchp_pit64b_cs_base); } -static u64 mchp_pit64b_sched_read_clk(void) +static u64 notrace mchp_pit64b_sched_read_clk(void) +{ + return mchp_pit64b_cnt_read(mchp_pit64b_cs_base); +} + +static unsigned long notrace mchp_pit64b_dt_read(void) { return mchp_pit64b_cnt_read(mchp_pit64b_cs_base); } static int mchp_pit64b_clkevt_shutdown(struct clock_event_device *cedev) { - struct mchp_pit64b_timer *timer = to_mchp_pit64b_timer(cedev); + struct mchp_pit64b_timer *timer = clkevt_to_mchp_pit64b_timer(cedev); - writel_relaxed(MCHP_PIT64B_CR_SWRST, timer->base + MCHP_PIT64B_CR); + if (!clockevent_state_detached(cedev)) + mchp_pit64b_suspend(timer); return 0; } static int mchp_pit64b_clkevt_set_periodic(struct clock_event_device *cedev) { - struct mchp_pit64b_timer *timer = to_mchp_pit64b_timer(cedev); + struct mchp_pit64b_timer *timer = clkevt_to_mchp_pit64b_timer(cedev); + + if (clockevent_state_shutdown(cedev)) + mchp_pit64b_resume(timer); mchp_pit64b_reset(timer, mchp_pit64b_ce_cycles, MCHP_PIT64B_MR_CONT, MCHP_PIT64B_IER_PERIOD); @@ -145,34 +200,28 @@ static int mchp_pit64b_clkevt_set_periodic(struct clock_event_device *cedev) return 0; } -static int mchp_pit64b_clkevt_set_next_event(unsigned long evt, - struct clock_event_device *cedev) +static int mchp_pit64b_clkevt_set_oneshot(struct clock_event_device *cedev) { - struct mchp_pit64b_timer *timer = to_mchp_pit64b_timer(cedev); + struct mchp_pit64b_timer *timer = clkevt_to_mchp_pit64b_timer(cedev); - mchp_pit64b_reset(timer, evt, MCHP_PIT64B_MR_ONE_SHOT, + if (clockevent_state_shutdown(cedev)) + mchp_pit64b_resume(timer); + + mchp_pit64b_reset(timer, mchp_pit64b_ce_cycles, MCHP_PIT64B_MR_ONE_SHOT, MCHP_PIT64B_IER_PERIOD); return 0; } -static void mchp_pit64b_clkevt_suspend(struct clock_event_device *cedev) +static int mchp_pit64b_clkevt_set_next_event(unsigned long evt, + struct clock_event_device *cedev) { - struct mchp_pit64b_timer *timer = to_mchp_pit64b_timer(cedev); + struct mchp_pit64b_timer *timer = clkevt_to_mchp_pit64b_timer(cedev); - writel_relaxed(MCHP_PIT64B_CR_SWRST, timer->base + MCHP_PIT64B_CR); - if (timer->mode & MCHP_PIT64B_MR_SGCLK) - clk_disable_unprepare(timer->gclk); - clk_disable_unprepare(timer->pclk); -} - -static void mchp_pit64b_clkevt_resume(struct clock_event_device *cedev) -{ - struct mchp_pit64b_timer *timer = to_mchp_pit64b_timer(cedev); + mchp_pit64b_reset(timer, evt, MCHP_PIT64B_MR_ONE_SHOT, + MCHP_PIT64B_IER_PERIOD); - clk_prepare_enable(timer->pclk); - if (timer->mode & MCHP_PIT64B_MR_SGCLK) - clk_prepare_enable(timer->gclk); + return 0; } static irqreturn_t mchp_pit64b_interrupt(int irq, void *dev_id) @@ -198,14 +247,16 @@ static void __init mchp_pit64b_pres_compute(u32 *pres, u32 clk_rate, break; } - /* Use the bigest prescaler if we didn't match one. */ + /* Use the biggest prescaler if we didn't match one. */ if (*pres == MCHP_PIT64B_PRES_MAX) *pres = MCHP_PIT64B_PRES_MAX - 1; } /** - * mchp_pit64b_init_mode - prepare PIT64B mode register value to be used at - * runtime; this includes prescaler and SGCLK bit + * mchp_pit64b_init_mode() - prepare PIT64B mode register value to be used at + * runtime; this includes prescaler and SGCLK bit + * @timer: pointer to pit64b timer to init + * @max_rate: maximum rate that timer's clock could use * * PIT64B timer may be fed by gclk or pclk. When gclk is used its rate has to * be at least 3 times lower that pclk's rate. pclk rate is fixed, gclk rate @@ -296,26 +347,47 @@ done: static int __init mchp_pit64b_init_clksrc(struct mchp_pit64b_timer *timer, u32 clk_rate) { + struct mchp_pit64b_clksrc *cs; int ret; + cs = kzalloc(sizeof(*cs), GFP_KERNEL); + if (!cs) + return -ENOMEM; + + mchp_pit64b_resume(timer); mchp_pit64b_reset(timer, ULLONG_MAX, MCHP_PIT64B_MR_CONT, 0); mchp_pit64b_cs_base = timer->base; - ret = clocksource_mmio_init(timer->base, MCHP_PIT64B_NAME, clk_rate, - 210, 64, mchp_pit64b_clksrc_read); + cs->timer.base = timer->base; + cs->timer.pclk = timer->pclk; + cs->timer.gclk = timer->gclk; + cs->timer.mode = timer->mode; + cs->clksrc.name = MCHP_PIT64B_NAME; + cs->clksrc.mask = CLOCKSOURCE_MASK(64); + cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; + cs->clksrc.rating = 210; + cs->clksrc.read = mchp_pit64b_clksrc_read; + cs->clksrc.suspend = mchp_pit64b_clksrc_suspend; + cs->clksrc.resume = mchp_pit64b_clksrc_resume; + + ret = clocksource_register_hz(&cs->clksrc, clk_rate); if (ret) { pr_debug("clksrc: Failed to register PIT64B clocksource!\n"); /* Stop timer. */ - writel_relaxed(MCHP_PIT64B_CR_SWRST, - timer->base + MCHP_PIT64B_CR); + mchp_pit64b_suspend(timer); + kfree(cs); return ret; } sched_clock_register(mchp_pit64b_sched_read_clk, 64, clk_rate); + mchp_pit64b_dt.read_current_timer = mchp_pit64b_dt_read; + mchp_pit64b_dt.freq = clk_rate; + register_current_timer_delay(&mchp_pit64b_dt); + return 0; } @@ -340,9 +412,8 @@ static int __init mchp_pit64b_init_clkevt(struct mchp_pit64b_timer *timer, ce->clkevt.rating = 150; ce->clkevt.set_state_shutdown = mchp_pit64b_clkevt_shutdown; ce->clkevt.set_state_periodic = mchp_pit64b_clkevt_set_periodic; + ce->clkevt.set_state_oneshot = mchp_pit64b_clkevt_set_oneshot; ce->clkevt.set_next_event = mchp_pit64b_clkevt_set_next_event; - ce->clkevt.suspend = mchp_pit64b_clkevt_suspend; - ce->clkevt.resume = mchp_pit64b_clkevt_resume; ce->clkevt.cpumask = cpumask_of(0); ce->clkevt.irq = irq; @@ -362,7 +433,6 @@ static int __init mchp_pit64b_init_clkevt(struct mchp_pit64b_timer *timer, static int __init mchp_pit64b_dt_init_timer(struct device_node *node, bool clkevt) { - u32 freq = clkevt ? MCHP_PIT64B_DEF_CE_FREQ : MCHP_PIT64B_DEF_CS_FREQ; struct mchp_pit64b_timer timer; unsigned long clk_rate; u32 irq = 0; @@ -390,23 +460,14 @@ static int __init mchp_pit64b_dt_init_timer(struct device_node *node, } /* Initialize mode (prescaler + SGCK bit). To be used at runtime. */ - ret = mchp_pit64b_init_mode(&timer, freq); + ret = mchp_pit64b_init_mode(&timer, MCHP_PIT64B_DEF_FREQ); if (ret) goto irq_unmap; - ret = clk_prepare_enable(timer.pclk); - if (ret) - goto irq_unmap; - - if (timer.mode & MCHP_PIT64B_MR_SGCLK) { - ret = clk_prepare_enable(timer.gclk); - if (ret) - goto pclk_unprepare; - + if (timer.mode & MCHP_PIT64B_MR_SGCLK) clk_rate = clk_get_rate(timer.gclk); - } else { + else clk_rate = clk_get_rate(timer.pclk); - } clk_rate = clk_rate / (MCHP_PIT64B_MODE_TO_PRES(timer.mode) + 1); if (clkevt) @@ -415,15 +476,10 @@ static int __init mchp_pit64b_dt_init_timer(struct device_node *node, ret = mchp_pit64b_init_clksrc(&timer, clk_rate); if (ret) - goto gclk_unprepare; + goto irq_unmap; return 0; -gclk_unprepare: - if (timer.mode & MCHP_PIT64B_MR_SGCLK) - clk_disable_unprepare(timer.gclk); -pclk_unprepare: - clk_disable_unprepare(timer.pclk); irq_unmap: irq_dispose_mapping(irq); io_unmap: |