diff options
Diffstat (limited to 'arch/arm/mach-omap2/timer.c')
| -rw-r--r-- | arch/arm/mach-omap2/timer.c | 97 |
1 files changed, 96 insertions, 1 deletions
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c index 810aa1a332e..8847d6eb231 100644 --- a/arch/arm/mach-omap2/timer.c +++ b/arch/arm/mach-omap2/timer.c @@ -42,6 +42,7 @@ #include <asm/smp_twd.h> #include <asm/sched_clock.h> +#include <asm/arch_timer.h> #include <plat/omap_hwmod.h> #include <plat/omap_device.h> #include <plat/dmtimer.h> @@ -72,6 +73,11 @@ #define OMAP3_SECURE_TIMER 1 #endif +#define REALTIME_COUNTER_BASE 0x48243200 +#define INCREMENTER_NUMERATOR_OFFSET 0x10 +#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14 +#define NUMERATOR_DENUMERATOR_MASK 0xfffff000 + /* Clockevent code */ static struct omap_dm_timer clkev; @@ -349,6 +355,84 @@ static void __init omap2_clocksource_init(int gptimer_id, omap2_gptimer_clocksource_init(gptimer_id, fck_source); } +#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER +/* + * The realtime counter also called master counter, is a free-running + * counter, which is related to real time. It produces the count used + * by the CPU local timer peripherals in the MPU cluster. The timer counts + * at a rate of 6.144 MHz. Because the device operates on different clocks + * in different power modes, the master counter shifts operation between + * clocks, adjusting the increment per clock in hardware accordingly to + * maintain a constant count rate. + */ +static void __init realtime_counter_init(void) +{ + void __iomem *base; + static struct clk *sys_clk; + unsigned long rate; + unsigned int reg, num, den; + + base = ioremap(REALTIME_COUNTER_BASE, SZ_32); + if (!base) { + pr_err("%s: ioremap failed\n", __func__); + return; + } + sys_clk = clk_get(NULL, "sys_clkin_ck"); + if (!sys_clk) { + pr_err("%s: failed to get system clock handle\n", __func__); + iounmap(base); + return; + } + + rate = clk_get_rate(sys_clk); + /* Numerator/denumerator values refer TRM Realtime Counter section */ + switch (rate) { + case 1200000: + num = 64; + den = 125; + break; + case 1300000: + num = 768; + den = 1625; + break; + case 19200000: + num = 8; + den = 25; + break; + case 2600000: + num = 384; + den = 1625; + break; + case 2700000: + num = 256; + den = 1125; + break; + case 38400000: + default: + /* Program it for 38.4 MHz */ + num = 4; + den = 25; + break; + } + + /* Program numerator and denumerator registers */ + reg = __raw_readl(base + INCREMENTER_NUMERATOR_OFFSET) & + NUMERATOR_DENUMERATOR_MASK; + reg |= num; + __raw_writel(reg, base + INCREMENTER_NUMERATOR_OFFSET); + + reg = __raw_readl(base + INCREMENTER_NUMERATOR_OFFSET) & + NUMERATOR_DENUMERATOR_MASK; + reg |= den; + __raw_writel(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET); + + iounmap(base); +} +#else +static inline void __init realtime_counter_init(void) +{} +#endif + #define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \ clksrc_nr, clksrc_src) \ static void __init omap##name##_timer_init(void) \ @@ -410,7 +494,18 @@ OMAP_SYS_TIMER(4) #endif #ifdef CONFIG_SOC_OMAP5 -OMAP_SYS_TIMER_INIT(5, 1, OMAP4_CLKEV_SOURCE, 2, OMAP4_MPU_SOURCE) +static void __init omap5_timer_init(void) +{ + int err; + + omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE); + omap2_clocksource_init(2, OMAP4_MPU_SOURCE); + realtime_counter_init(); + + err = arch_timer_of_register(); + if (err) + pr_err("%s: arch_timer_register failed %d\n", __func__, err); +} OMAP_SYS_TIMER(5) #endif |