linux/arch/arm/mach-at91/pm.h
Albin Tonnerre 1ea60cf706 ARM: 5778/1: AT91: Add cpuidle support
This patch adds the support for cpuidle on AT91 SoCs, taken from the
cpuidle support in mach-kirkwood.
cpuidle needs sdram_selfrefresh_enable and _disable, so move their
definition to a separate header file instead of duplicating the code
already used in pm.c.

Tested-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Acked-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-10 23:46:35 +00:00

68 lines
1.8 KiB
C

#ifdef CONFIG_ARCH_AT91RM9200
#include <mach/at91rm9200_mc.h>
/*
* The AT91RM9200 goes into self-refresh mode with this command, and will
* terminate self-refresh automatically on the next SDRAM access.
*
* Self-refresh mode is exited as soon as a memory access is made, but we don't
* know for sure when that happens. However, we need to restore the low-power
* mode if it was enabled before going idle. Restoring low-power mode while
* still in self-refresh is "not recommended", but seems to work.
*/
static inline u32 sdram_selfrefresh_enable(void)
{
u32 saved_lpr = at91_sys_read(AT91_SDRAMC_LPR);
at91_sys_write(AT91_SDRAMC_LPR, 0);
at91_sys_write(AT91_SDRAMC_SRR, 1);
return saved_lpr;
}
#define sdram_selfrefresh_disable(saved_lpr) at91_sys_write(AT91_SDRAMC_LPR, saved_lpr)
#elif defined(CONFIG_ARCH_AT91CAP9)
#include <mach/at91cap9_ddrsdr.h>
static inline u32 sdram_selfrefresh_enable(void)
{
u32 saved_lpr, 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);
return saved_lpr;
}
#define sdram_selfrefresh_disable(saved_lpr) at91_sys_write(AT91_DDRSDRC_LPR, saved_lpr)
#else
#include <mach/at91sam9_sdramc.h>
#ifdef CONFIG_ARCH_AT91SAM9263
/*
* FIXME either or both the SDRAM controllers (EB0, EB1) might be in use;
* handle those cases both here and in the Suspend-To-RAM support.
*/
#define AT91_SDRAMC AT91_SDRAMC0
#warning Assuming EB1 SDRAM controller is *NOT* used
#endif
static inline u32 sdram_selfrefresh_enable(void)
{
u32 saved_lpr, 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);
return saved_lpr;
}
#define sdram_selfrefresh_disable(saved_lpr) at91_sys_write(AT91_SDRAMC_LPR, saved_lpr)
#endif