diff options
Diffstat (limited to 'arch/arm/mach-at91/pm.c')
| -rw-r--r-- | arch/arm/mach-at91/pm.c | 165 |
1 files changed, 149 insertions, 16 deletions
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index a67defd50438..39733b6992aa 100644 --- a/arch/arm/mach-at91/pm.c +++ b/arch/arm/mach-at91/pm.c @@ -26,12 +26,135 @@ #include <asm/mach-types.h> #include <asm/arch/at91_pmc.h> -#include <asm/arch/at91rm9200_mc.h> #include <asm/arch/gpio.h> #include <asm/arch/cpu.h> #include "generic.h" +#ifdef CONFIG_ARCH_AT91RM9200 +#include <asm/arch/at91rm9200_mc.h> + +/* + * The AT91RM9200 goes into self-refresh mode with this command, and will + * terminate self-refresh automatically on the next SDRAM access. + */ +#define sdram_selfrefresh_enable() at91_sys_write(AT91_SDRAMC_SRR, 1) +#define sdram_selfrefresh_disable() do {} while (0) + +#elif defined(CONFIG_ARCH_AT91CAP9) +#include <asm/arch/at91cap9_ddrsdr.h> + +static u32 saved_lpr; + +static inline void sdram_selfrefresh_enable(void) +{ + u32 lpr; + + saved_lpr = at91_sys_read(AT91_DDRSDRC_LPR); + + lpr = saved_lpr & ~AT91_DDRSDRC_LPCB; + at91_sys_write(AT91_DDRSDRC_LPR, lpr | AT91_DDRSDRC_LPCB_SELF_REFRESH); +} + +#define sdram_selfrefresh_disable() at91_sys_write(AT91_DDRSDRC_LPR, saved_lpr) + +#else +#include <asm/arch/at91sam9_sdramc.h> + +static u32 saved_lpr; + +static inline void sdram_selfrefresh_enable(void) +{ + u32 lpr; + + saved_lpr = at91_sys_read(AT91_SDRAMC_LPR); + + lpr = saved_lpr & ~AT91_SDRAMC_LPCB; + at91_sys_write(AT91_SDRAMC_LPR, lpr | AT91_SDRAMC_LPCB_SELF_REFRESH); +} + +#define sdram_selfrefresh_disable() at91_sys_write(AT91_SDRAMC_LPR, saved_lpr) + +/* + * FIXME: The AT91SAM9263 has a second EBI controller which may have + * additional SDRAM. pm_slowclock.S will require a similar fix. + */ + +#endif + + +/* + * Show the reason for the previous system reset. + */ +#if defined(AT91_SHDWC) + +#include <asm/arch/at91_rstc.h> +#include <asm/arch/at91_shdwc.h> + +static void __init show_reset_status(void) +{ + static char reset[] __initdata = "reset"; + + static char general[] __initdata = "general"; + static char wakeup[] __initdata = "wakeup"; + static char watchdog[] __initdata = "watchdog"; + static char software[] __initdata = "software"; + static char user[] __initdata = "user"; + static char unknown[] __initdata = "unknown"; + + static char signal[] __initdata = "signal"; + static char rtc[] __initdata = "rtc"; + static char rtt[] __initdata = "rtt"; + static char restore[] __initdata = "power-restored"; + + char *reason, *r2 = reset; + u32 reset_type, wake_type; + + reset_type = at91_sys_read(AT91_RSTC_SR) & AT91_RSTC_RSTTYP; + wake_type = at91_sys_read(AT91_SHDW_SR); + + switch (reset_type) { + case AT91_RSTC_RSTTYP_GENERAL: + reason = general; + break; + case AT91_RSTC_RSTTYP_WAKEUP: + /* board-specific code enabled the wakeup sources */ + reason = wakeup; + + /* "wakeup signal" */ + if (wake_type & AT91_SHDW_WAKEUP0) + r2 = signal; + else { + r2 = reason; + if (wake_type & AT91_SHDW_RTTWK) /* rtt wakeup */ + reason = rtt; + else if (wake_type & AT91_SHDW_RTCWK) /* rtc wakeup */ + reason = rtc; + else if (wake_type == 0) /* power-restored wakeup */ + reason = restore; + else /* unknown wakeup */ + reason = unknown; + } + break; + case AT91_RSTC_RSTTYP_WATCHDOG: + reason = watchdog; + break; + case AT91_RSTC_RSTTYP_SOFTWARE: + reason = software; + break; + case AT91_RSTC_RSTTYP_USER: + reason = user; + break; + default: + reason = unknown; + break; + } + pr_info("AT91: Starting after %s %s\n", reason, r2); +} +#else +static void __init show_reset_status(void) {} +#endif + static int at91_pm_valid_state(suspend_state_t state) { @@ -125,6 +248,11 @@ EXPORT_SYMBOL(at91_suspend_entering_slow_clock); static void (*slow_clock)(void); +#ifdef CONFIG_AT91_SLOW_CLOCK +extern void at91_slow_clock(void); +extern u32 at91_slow_clock_sz; +#endif + static int at91_pm_enter(suspend_state_t state) { @@ -158,11 +286,14 @@ static int at91_pm_enter(suspend_state_t state) * turning off the main oscillator; reverse on wakeup. */ if (slow_clock) { +#ifdef CONFIG_AT91_SLOW_CLOCK + /* copy slow_clock handler to SRAM, and call it */ + memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz); +#endif slow_clock(); break; } else { - /* DEVELOPMENT ONLY */ - pr_info("AT91: PM - no slow clock mode yet ...\n"); + pr_info("AT91: PM - no slow clock mode enabled ...\n"); /* FALLTHROUGH leaving master clock alone */ } @@ -175,13 +306,15 @@ static int at91_pm_enter(suspend_state_t state) case PM_SUSPEND_STANDBY: /* * NOTE: the Wait-for-Interrupt instruction needs to be - * in icache so the SDRAM stays in self-refresh mode until - * the wakeup IRQ occurs. + * in icache so no SDRAM accesses are needed until the + * wakeup IRQ occurs and self-refresh is terminated. */ asm("b 1f; .align 5; 1:"); asm("mcr p15, 0, r0, c7, c10, 4"); /* drain write buffer */ - at91_sys_write(AT91_SDRAMC_SRR, 1); /* self-refresh mode */ - /* fall though to next state */ + sdram_selfrefresh_enable(); + asm("mcr p15, 0, r0, c7, c0, 4"); /* wait for interrupt */ + sdram_selfrefresh_disable(); + break; case PM_SUSPEND_ON: asm("mcr p15, 0, r0, c7, c0, 4"); /* wait for interrupt */ @@ -196,6 +329,7 @@ static int at91_pm_enter(suspend_state_t state) at91_sys_read(AT91_AIC_IPR) & at91_sys_read(AT91_AIC_IMR)); error: + sdram_selfrefresh_disable(); target_state = PM_SUSPEND_ON; at91_irq_resume(); at91_gpio_resume(); @@ -220,21 +354,20 @@ static struct platform_suspend_ops at91_pm_ops ={ static int __init at91_pm_init(void) { - printk("AT91: Power Management\n"); - -#ifdef CONFIG_AT91_PM_SLOW_CLOCK - /* REVISIT allocations of SRAM should be dynamically managed. - * FIQ handlers and other components will want SRAM/TCM too... - */ - slow_clock = (void *) (AT91_VA_BASE_SRAM + (3 * SZ_4K)); - memcpy(slow_clock, at91rm9200_slow_clock, at91rm9200_slow_clock_sz); +#ifdef CONFIG_AT91_SLOW_CLOCK + slow_clock = (void *) (AT91_IO_VIRT_BASE - at91_slow_clock_sz); #endif - /* Disable SDRAM low-power mode. Cannot be used with self-refresh. */ + pr_info("AT91: Power Management%s\n", (slow_clock ? " (with slow clock mode)" : "")); + +#ifdef CONFIG_ARCH_AT91RM9200 + /* AT91RM9200 SDRAM low-power mode cannot be used with self-refresh. */ at91_sys_write(AT91_SDRAMC_LPR, 0); +#endif suspend_set_ops(&at91_pm_ops); + show_reset_status(); return 0; } arch_initcall(at91_pm_init); |