diff options
Diffstat (limited to 'arch/arm/mach-omap2/timer.c')
| -rw-r--r-- | arch/arm/mach-omap2/timer.c | 118 |
1 files changed, 93 insertions, 25 deletions
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c index 1b7835865c83..840929bd9dae 100644 --- a/arch/arm/mach-omap2/timer.c +++ b/arch/arm/mach-omap2/timer.c @@ -90,7 +90,7 @@ static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id) } static struct irqaction omap2_gp_timer_irq = { - .name = "gp timer", + .name = "gp_timer", .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, .handler = omap2_gp_timer_interrupt, }; @@ -132,7 +132,7 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode, } static struct clock_event_device clockevent_gpt = { - .name = "gp timer", + .name = "gp_timer", .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, .shift = 32, .set_next_event = omap2_gp_timer_set_next_event, @@ -236,22 +236,8 @@ static void __init omap2_gp_clockevent_init(int gptimer_id, } /* Clocksource code */ - -#ifdef CONFIG_OMAP_32K_TIMER -/* - * When 32k-timer is enabled, don't use GPTimer for clocksource - * instead, just leave default clocksource which uses the 32k - * sync counter. See clocksource setup in plat-omap/counter_32k.c - */ - -static void __init omap2_gp_clocksource_init(int unused, const char *dummy) -{ - omap_init_clocksource_32k(); -} - -#else - static struct omap_dm_timer clksrc; +static bool use_gptimer_clksrc; /* * clocksource @@ -262,7 +248,7 @@ static cycle_t clocksource_read_cycles(struct clocksource *cs) } static struct clocksource clocksource_gpt = { - .name = "gp timer", + .name = "gp_timer", .rating = 300, .read = clocksource_read_cycles, .mask = CLOCKSOURCE_MASK(32), @@ -278,7 +264,46 @@ static u32 notrace dmtimer_read_sched_clock(void) } /* Setup free-running counter for clocksource */ -static void __init omap2_gp_clocksource_init(int gptimer_id, +static int __init omap2_sync32k_clocksource_init(void) +{ + int ret; + struct omap_hwmod *oh; + void __iomem *vbase; + const char *oh_name = "counter_32k"; + + /* + * First check hwmod data is available for sync32k counter + */ + oh = omap_hwmod_lookup(oh_name); + if (!oh || oh->slaves_cnt == 0) + return -ENODEV; + + omap_hwmod_setup_one(oh_name); + + vbase = omap_hwmod_get_mpu_rt_va(oh); + if (!vbase) { + pr_warn("%s: failed to get counter_32k resource\n", __func__); + return -ENXIO; + } + + ret = omap_hwmod_enable(oh); + if (ret) { + pr_warn("%s: failed to enable counter_32k module (%d)\n", + __func__, ret); + return ret; + } + + ret = omap_init_clocksource_32k(vbase); + if (ret) { + pr_warn("%s: failed to initialize counter_32k as a clocksource (%d)\n", + __func__, ret); + omap_hwmod_idle(oh); + } + + return ret; +} + +static void __init omap2_gptimer_clocksource_init(int gptimer_id, const char *fck_source) { int res; @@ -286,9 +311,6 @@ static void __init omap2_gp_clocksource_init(int gptimer_id, res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source); BUG_ON(res); - pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n", - gptimer_id, clksrc.rate); - __omap_dm_timer_load_start(&clksrc, OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1); setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate); @@ -296,15 +318,36 @@ static void __init omap2_gp_clocksource_init(int gptimer_id, if (clocksource_register_hz(&clocksource_gpt, clksrc.rate)) pr_err("Could not register clocksource %s\n", clocksource_gpt.name); + else + pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n", + gptimer_id, clksrc.rate); +} + +static void __init omap2_clocksource_init(int gptimer_id, + const char *fck_source) +{ + /* + * First give preference to kernel parameter configuration + * by user (clocksource="gp_timer"). + * + * In case of missing kernel parameter for clocksource, + * first check for availability for 32k-sync timer, in case + * of failure in finding 32k_counter module or registering + * it as clocksource, execution will fallback to gp-timer. + */ + if (use_gptimer_clksrc == true) + omap2_gptimer_clocksource_init(gptimer_id, fck_source); + else if (omap2_sync32k_clocksource_init()) + /* Fall back to gp-timer code */ + omap2_gptimer_clocksource_init(gptimer_id, fck_source); } -#endif #define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \ clksrc_nr, clksrc_src) \ static void __init omap##name##_timer_init(void) \ { \ omap2_gp_clockevent_init((clkev_nr), clkev_src); \ - omap2_gp_clocksource_init((clksrc_nr), clksrc_src); \ + omap2_clocksource_init((clksrc_nr), clksrc_src); \ } #define OMAP_SYS_TIMER(name) \ @@ -335,7 +378,7 @@ static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, static void __init omap4_timer_init(void) { omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE); - omap2_gp_clocksource_init(2, OMAP4_MPU_SOURCE); + omap2_clocksource_init(2, OMAP4_MPU_SOURCE); #ifdef CONFIG_LOCAL_TIMERS /* Local timers are not supprted on OMAP4430 ES1.0 */ if (omap_rev() != OMAP4430_REV_ES1_0) { @@ -503,3 +546,28 @@ static int __init omap2_dm_timer_init(void) return 0; } arch_initcall(omap2_dm_timer_init); + +/** + * omap2_override_clocksource - clocksource override with user configuration + * + * Allows user to override default clocksource, using kernel parameter + * clocksource="gp_timer" (For all OMAP2PLUS architectures) + * + * Note that, here we are using same standard kernel parameter "clocksource=", + * and not introducing any OMAP specific interface. + */ +static int __init omap2_override_clocksource(char *str) +{ + if (!str) + return 0; + /* + * For OMAP architecture, we only have two options + * - sync_32k (default) + * - gp_timer (sys_clk based) + */ + if (!strcmp(str, "gp_timer")) + use_gptimer_clksrc = true; + + return 0; +} +early_param("clocksource", omap2_override_clocksource); |