diff options
Diffstat (limited to 'arch/arm/mach-at91/pm.c')
| -rw-r--r-- | arch/arm/mach-at91/pm.c | 91 |
1 files changed, 75 insertions, 16 deletions
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index a67defd5043..77d9669810e 100644 --- a/arch/arm/mach-at91/pm.c +++ b/arch/arm/mach-at91/pm.c @@ -26,12 +26,62 @@ #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 + static int at91_pm_valid_state(suspend_state_t state) { @@ -125,6 +175,11 @@ 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 +213,14 @@ 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 +233,15 @@ 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 +256,7 @@ 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(); @@ -220,18 +281,16 @@ 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); |