From 546a39546c64ad7e73796c5508ef5487af42cae2 Mon Sep 17 00:00:00 2001 From: Aurelien Jacquiot Date: Tue, 4 Oct 2011 11:05:33 -0400 Subject: C6X: time management Original port to early 2.6 kernel using TI COFF toolchain. Brought up to date by Mark Salter Signed-off-by: Aurelien Jacquiot Signed-off-by: Mark Salter Reviewed-by: Thomas Gleixner Acked-by: Arnd Bergmann diff --git a/arch/c6x/include/asm/timer64.h b/arch/c6x/include/asm/timer64.h new file mode 100644 index 0000000..bbe27bb --- /dev/null +++ b/arch/c6x/include/asm/timer64.h @@ -0,0 +1,6 @@ +#ifndef _C6X_TIMER64_H +#define _C6X_TIMER64_H + +extern void __init timer64_init(void); + +#endif /* _C6X_TIMER64_H */ diff --git a/arch/c6x/include/asm/timex.h b/arch/c6x/include/asm/timex.h new file mode 100644 index 0000000..508c3ec --- /dev/null +++ b/arch/c6x/include/asm/timex.h @@ -0,0 +1,33 @@ +/* + * Port on Texas Instruments TMS320C6x architecture + * + * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated + * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com) + * + * Modified for 2.6.34: Mark Salter + * + * 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. + */ +#ifndef _ASM_C6X_TIMEX_H +#define _ASM_C6X_TIMEX_H + +#define CLOCK_TICK_RATE ((1000 * 1000000UL) / 6) + +/* 64-bit timestamp */ +typedef unsigned long long cycles_t; + +static inline cycles_t get_cycles(void) +{ + unsigned l, h; + + asm volatile (" dint\n" + " mvc .s2 TSCL,%0\n" + " mvc .s2 TSCH,%1\n" + " rint\n" + : "=b"(l), "=b"(h)); + return ((cycles_t)h << 32) | l; +} + +#endif /* _ASM_C6X_TIMEX_H */ diff --git a/arch/c6x/kernel/time.c b/arch/c6x/kernel/time.c new file mode 100644 index 0000000..4c9f136 --- /dev/null +++ b/arch/c6x/kernel/time.c @@ -0,0 +1,65 @@ +/* + * Port on Texas Instruments TMS320C6x architecture + * + * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated + * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com) + * + * 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 +#include +#include +#include +#include + +#include + +static u32 sched_clock_multiplier; +#define SCHED_CLOCK_SHIFT 16 + +static cycle_t tsc_read(struct clocksource *cs) +{ + return get_cycles(); +} + +static struct clocksource clocksource_tsc = { + .name = "timestamp", + .rating = 300, + .read = tsc_read, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +/* + * scheduler clock - returns current time in nanoseconds. + */ +u64 sched_clock(void) +{ + u64 tsc = get_cycles(); + + return (tsc * sched_clock_multiplier) >> SCHED_CLOCK_SHIFT; +} + +void time_init(void) +{ + u64 tmp = (u64)NSEC_PER_SEC << SCHED_CLOCK_SHIFT; + + do_div(tmp, c6x_core_freq); + sched_clock_multiplier = tmp; + + clocksource_register_hz(&clocksource_tsc, c6x_core_freq); + + /* write anything into TSCL to enable counting */ + set_creg(TSCL, 0); + + /* probe for timer64 event timer */ + timer64_init(); +} diff --git a/arch/c6x/platforms/timer64.c b/arch/c6x/platforms/timer64.c new file mode 100644 index 0000000..7834158 --- /dev/null +++ b/arch/c6x/platforms/timer64.c @@ -0,0 +1,236 @@ +/* + * Copyright (C) 2010, 2011 Texas Instruments Incorporated + * Contributed by: Mark Salter (msalter@redhat.com) + * + * 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 +#include +#include +#include + +struct timer_regs { + u32 reserved0; + u32 emumgt; + u32 reserved1; + u32 reserved2; + u32 cntlo; + u32 cnthi; + u32 prdlo; + u32 prdhi; + u32 tcr; + u32 tgcr; + u32 wdtcr; +}; + +static struct timer_regs __iomem *timer; + +#define TCR_TSTATLO 0x001 +#define TCR_INVOUTPLO 0x002 +#define TCR_INVINPLO 0x004 +#define TCR_CPLO 0x008 +#define TCR_ENAMODELO_ONCE 0x040 +#define TCR_ENAMODELO_CONT 0x080 +#define TCR_ENAMODELO_MASK 0x0c0 +#define TCR_PWIDLO_MASK 0x030 +#define TCR_CLKSRCLO 0x100 +#define TCR_TIENLO 0x200 +#define TCR_TSTATHI (0x001 << 16) +#define TCR_INVOUTPHI (0x002 << 16) +#define TCR_CPHI (0x008 << 16) +#define TCR_PWIDHI_MASK (0x030 << 16) +#define TCR_ENAMODEHI_ONCE (0x040 << 16) +#define TCR_ENAMODEHI_CONT (0x080 << 16) +#define TCR_ENAMODEHI_MASK (0x0c0 << 16) + +#define TGCR_TIMLORS 0x001 +#define TGCR_TIMHIRS 0x002 +#define TGCR_TIMMODE_UD32 0x004 +#define TGCR_TIMMODE_WDT64 0x008 +#define TGCR_TIMMODE_CD32 0x00c +#define TGCR_TIMMODE_MASK 0x00c +#define TGCR_PSCHI_MASK (0x00f << 8) +#define TGCR_TDDRHI_MASK (0x00f << 12) + +/* + * Timer clocks are divided down from the CPU clock + * The divisor is in the EMUMGTCLKSPD register + */ +#define TIMER_DIVISOR \ + ((soc_readl(&timer->emumgt) & (0xf << 16)) >> 16) + +#define TIMER64_RATE (c6x_core_freq / TIMER_DIVISOR) + +#define TIMER64_MODE_DISABLED 0 +#define TIMER64_MODE_ONE_SHOT TCR_ENAMODELO_ONCE +#define TIMER64_MODE_PERIODIC TCR_ENAMODELO_CONT + +static int timer64_mode; +static int timer64_devstate_id = -1; + +static void timer64_config(unsigned long period) +{ + u32 tcr = soc_readl(&timer->tcr) & ~TCR_ENAMODELO_MASK; + + soc_writel(tcr, &timer->tcr); + soc_writel(period - 1, &timer->prdlo); + soc_writel(0, &timer->cntlo); + tcr |= timer64_mode; + soc_writel(tcr, &timer->tcr); +} + +static void timer64_enable(void) +{ + u32 val; + + if (timer64_devstate_id >= 0) + dscr_set_devstate(timer64_devstate_id, DSCR_DEVSTATE_ENABLED); + + /* disable timer, reset count */ + soc_writel(soc_readl(&timer->tcr) & ~TCR_ENAMODELO_MASK, &timer->tcr); + soc_writel(0, &timer->prdlo); + + /* use internal clock and 1 cycle pulse width */ + val = soc_readl(&timer->tcr); + soc_writel(val & ~(TCR_CLKSRCLO | TCR_PWIDLO_MASK), &timer->tcr); + + /* dual 32-bit unchained mode */ + val = soc_readl(&timer->tgcr) & ~TGCR_TIMMODE_MASK; + soc_writel(val, &timer->tgcr); + soc_writel(val | (TGCR_TIMLORS | TGCR_TIMMODE_UD32), &timer->tgcr); +} + +static void timer64_disable(void) +{ + /* disable timer, reset count */ + soc_writel(soc_readl(&timer->tcr) & ~TCR_ENAMODELO_MASK, &timer->tcr); + soc_writel(0, &timer->prdlo); + + if (timer64_devstate_id >= 0) + dscr_set_devstate(timer64_devstate_id, DSCR_DEVSTATE_DISABLED); +} + +static int next_event(unsigned long delta, + struct clock_event_device *evt) +{ + timer64_config(delta); + return 0; +} + +static void set_clock_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + timer64_enable(); + timer64_mode = TIMER64_MODE_PERIODIC; + timer64_config(TIMER64_RATE / HZ); + break; + case CLOCK_EVT_MODE_ONESHOT: + timer64_enable(); + timer64_mode = TIMER64_MODE_ONE_SHOT; + break; + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + timer64_mode = TIMER64_MODE_DISABLED; + timer64_disable(); + break; + case CLOCK_EVT_MODE_RESUME: + break; + } +} + +static struct clock_event_device t64_clockevent_device = { + .name = "TIMER64_EVT32_TIMER", + .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, + .rating = 200, + .set_mode = set_clock_mode, + .set_next_event = next_event, +}; + +static irqreturn_t timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *cd = &t64_clockevent_device; + + cd->event_handler(cd); + + return IRQ_HANDLED; +} + +static struct irqaction timer_iact = { + .name = "timer", + .flags = IRQF_TIMER, + .handler = timer_interrupt, + .dev_id = &t64_clockevent_device, +}; + +void __init timer64_init(void) +{ + struct clock_event_device *cd = &t64_clockevent_device; + struct device_node *np, *first = NULL; + u32 val; + int err, found = 0; + + for_each_compatible_node(np, NULL, "ti,c64x+timer64") { + err = of_property_read_u32(np, "ti,core-mask", &val); + if (!err) { + if (val & (1 << get_coreid())) { + found = 1; + break; + } + } else if (!first) + first = np; + } + if (!found) { + /* try first one with no core-mask */ + if (first) + np = of_node_get(first); + else { + pr_debug("Cannot find ti,c64x+timer64 timer.\n"); + return; + } + } + + timer = of_iomap(np, 0); + if (!timer) { + pr_debug("%s: Cannot map timer registers.\n", np->full_name); + goto out; + } + pr_debug("%s: Timer registers=%p.\n", np->full_name, timer); + + cd->irq = irq_of_parse_and_map(np, 0); + if (cd->irq == NO_IRQ) { + pr_debug("%s: Cannot find interrupt.\n", np->full_name); + iounmap(timer); + goto out; + } + + /* If there is a device state control, save the ID. */ + err = of_property_read_u32(np, "ti,dscr-dev-enable", &val); + if (!err) + timer64_devstate_id = val; + + pr_debug("%s: Timer irq=%d.\n", np->full_name, cd->irq); + + clockevents_calc_mult_shift(cd, c6x_core_freq / TIMER_DIVISOR, 5); + + cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd); + cd->min_delta_ns = clockevent_delta2ns(250, cd); + + cd->cpumask = cpumask_of(smp_processor_id()); + + clockevents_register_device(cd); + setup_irq(cd->irq, &timer_iact); + +out: + of_node_put(np); + return; +} -- cgit v0.10.2