diff options
Diffstat (limited to 'arch/mips/kernel/cevt-txx9.c')
| -rw-r--r-- | arch/mips/kernel/cevt-txx9.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/arch/mips/kernel/cevt-txx9.c b/arch/mips/kernel/cevt-txx9.c new file mode 100644 index 000000000..d761ead2e --- /dev/null +++ b/arch/mips/kernel/cevt-txx9.c @@ -0,0 +1,220 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Based on linux/arch/mips/kernel/cevt-r4k.c, + * linux/arch/mips/jmr3927/rbhma3100/setup.c + * + * Copyright 2001 MontaVista Software Inc. + * Copyright (C) 2000-2001 Toshiba Corporation + * Copyright (C) 2007 MIPS Technologies, Inc. + * Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org> + */ +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/sched_clock.h> +#include <asm/time.h> +#include <asm/txx9tmr.h> + +#define TCR_BASE (TXx9_TMTCR_CCDE | TXx9_TMTCR_CRE | TXx9_TMTCR_TMODE_ITVL) +#define TIMER_CCD 0 /* 1/2 */ +#define TIMER_CLK(imclk) ((imclk) / (2 << TIMER_CCD)) + +struct txx9_clocksource { + struct clocksource cs; + struct txx9_tmr_reg __iomem *tmrptr; +}; + +static u64 txx9_cs_read(struct clocksource *cs) +{ + struct txx9_clocksource *txx9_cs = + container_of(cs, struct txx9_clocksource, cs); + return __raw_readl(&txx9_cs->tmrptr->trr); +} + +/* Use 1 bit smaller width to use full bits in that width */ +#define TXX9_CLOCKSOURCE_BITS (TXX9_TIMER_BITS - 1) + +static struct txx9_clocksource txx9_clocksource = { + .cs = { + .name = "TXx9", + .rating = 200, + .read = txx9_cs_read, + .mask = CLOCKSOURCE_MASK(TXX9_CLOCKSOURCE_BITS), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + }, +}; + +static u64 notrace txx9_read_sched_clock(void) +{ + return __raw_readl(&txx9_clocksource.tmrptr->trr); +} + +void __init txx9_clocksource_init(unsigned long baseaddr, + unsigned int imbusclk) +{ + struct txx9_tmr_reg __iomem *tmrptr; + + clocksource_register_hz(&txx9_clocksource.cs, TIMER_CLK(imbusclk)); + + tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg)); + __raw_writel(TCR_BASE, &tmrptr->tcr); + __raw_writel(0, &tmrptr->tisr); + __raw_writel(TIMER_CCD, &tmrptr->ccdr); + __raw_writel(TXx9_TMITMR_TZCE, &tmrptr->itmr); + __raw_writel(1 << TXX9_CLOCKSOURCE_BITS, &tmrptr->cpra); + __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr); + txx9_clocksource.tmrptr = tmrptr; + + sched_clock_register(txx9_read_sched_clock, TXX9_CLOCKSOURCE_BITS, + TIMER_CLK(imbusclk)); +} + +struct txx9_clock_event_device { + struct clock_event_device cd; + struct txx9_tmr_reg __iomem *tmrptr; +}; + +static void txx9tmr_stop_and_clear(struct txx9_tmr_reg __iomem *tmrptr) +{ + /* stop and reset counter */ + __raw_writel(TCR_BASE, &tmrptr->tcr); + /* clear pending interrupt */ + __raw_writel(0, &tmrptr->tisr); +} + +static int txx9tmr_set_state_periodic(struct clock_event_device *evt) +{ + struct txx9_clock_event_device *txx9_cd = + container_of(evt, struct txx9_clock_event_device, cd); + struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr; + + txx9tmr_stop_and_clear(tmrptr); + + __raw_writel(TXx9_TMITMR_TIIE | TXx9_TMITMR_TZCE, &tmrptr->itmr); + /* start timer */ + __raw_writel(((u64)(NSEC_PER_SEC / HZ) * evt->mult) >> evt->shift, + &tmrptr->cpra); + __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr); + return 0; +} + +static int txx9tmr_set_state_oneshot(struct clock_event_device *evt) +{ + struct txx9_clock_event_device *txx9_cd = + container_of(evt, struct txx9_clock_event_device, cd); + struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr; + + txx9tmr_stop_and_clear(tmrptr); + __raw_writel(TXx9_TMITMR_TIIE, &tmrptr->itmr); + return 0; +} + +static int txx9tmr_set_state_shutdown(struct clock_event_device *evt) +{ + struct txx9_clock_event_device *txx9_cd = + container_of(evt, struct txx9_clock_event_device, cd); + struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr; + + txx9tmr_stop_and_clear(tmrptr); + __raw_writel(0, &tmrptr->itmr); + return 0; +} + +static int txx9tmr_tick_resume(struct clock_event_device *evt) +{ + struct txx9_clock_event_device *txx9_cd = + container_of(evt, struct txx9_clock_event_device, cd); + struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr; + + txx9tmr_stop_and_clear(tmrptr); + __raw_writel(TIMER_CCD, &tmrptr->ccdr); + __raw_writel(0, &tmrptr->itmr); + return 0; +} + +static int txx9tmr_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + struct txx9_clock_event_device *txx9_cd = + container_of(evt, struct txx9_clock_event_device, cd); + struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr; + + txx9tmr_stop_and_clear(tmrptr); + /* start timer */ + __raw_writel(delta, &tmrptr->cpra); + __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr); + return 0; +} + +static struct txx9_clock_event_device txx9_clock_event_device = { + .cd = { + .name = "TXx9", + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + .rating = 200, + .set_state_shutdown = txx9tmr_set_state_shutdown, + .set_state_periodic = txx9tmr_set_state_periodic, + .set_state_oneshot = txx9tmr_set_state_oneshot, + .tick_resume = txx9tmr_tick_resume, + .set_next_event = txx9tmr_set_next_event, + }, +}; + +static irqreturn_t txx9tmr_interrupt(int irq, void *dev_id) +{ + struct txx9_clock_event_device *txx9_cd = dev_id; + struct clock_event_device *cd = &txx9_cd->cd; + struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr; + + __raw_writel(0, &tmrptr->tisr); /* ack interrupt */ + cd->event_handler(cd); + return IRQ_HANDLED; +} + +void __init txx9_clockevent_init(unsigned long baseaddr, int irq, + unsigned int imbusclk) +{ + struct clock_event_device *cd = &txx9_clock_event_device.cd; + struct txx9_tmr_reg __iomem *tmrptr; + + tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg)); + txx9tmr_stop_and_clear(tmrptr); + __raw_writel(TIMER_CCD, &tmrptr->ccdr); + __raw_writel(0, &tmrptr->itmr); + txx9_clock_event_device.tmrptr = tmrptr; + + clockevent_set_clock(cd, TIMER_CLK(imbusclk)); + cd->max_delta_ns = + clockevent_delta2ns(0xffffffff >> (32 - TXX9_TIMER_BITS), cd); + cd->max_delta_ticks = 0xffffffff >> (32 - TXX9_TIMER_BITS); + cd->min_delta_ns = clockevent_delta2ns(0xf, cd); + cd->min_delta_ticks = 0xf; + cd->irq = irq; + cd->cpumask = cpumask_of(0); + clockevents_register_device(cd); + if (request_irq(irq, txx9tmr_interrupt, IRQF_PERCPU | IRQF_TIMER, + "txx9tmr", &txx9_clock_event_device)) + pr_err("Failed to request irq %d (txx9tmr)\n", irq); + printk(KERN_INFO "TXx9: clockevent device at 0x%lx, irq %d\n", + baseaddr, irq); +} + +void __init txx9_tmr_init(unsigned long baseaddr) +{ + struct txx9_tmr_reg __iomem *tmrptr; + + tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg)); + /* Start once to make CounterResetEnable effective */ + __raw_writel(TXx9_TMTCR_CRE | TXx9_TMTCR_TCE, &tmrptr->tcr); + /* Stop and reset the counter */ + __raw_writel(TXx9_TMTCR_CRE, &tmrptr->tcr); + __raw_writel(0, &tmrptr->tisr); + __raw_writel(0xffffffff, &tmrptr->cpra); + __raw_writel(0, &tmrptr->itmr); + __raw_writel(0, &tmrptr->ccdr); + __raw_writel(0, &tmrptr->pgmr); + iounmap(tmrptr); +} |