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linux-2.6/arch/arm/mach-at91/pm.h
Nicolas Ferre 7dca3343fc ARM: 6185/1: AT91: PM: dual ram controller support
This rework allows to address tow memory controllers. AT91SAM9263 and
AT91SAM9G45 family have tow SDRAM or DDR/SDRAM controllers. Power management
should take care of this.
This patch modify the way RAM IP header files are implemented to allow
access to registers of both controllers ; it also adds some macros.

We also modify the power management files to use those modified header files.
Slow clock (assembly) and regular power management functions are synchronized
for setting of RAM self-refresh procedure:
(lpr & ~AT91_DDRSDRC_LPCB) | AT91_DDRSDRC_LPCB_SELF_REFRESH

Note that AT91RM9200 is not impacted by this modification.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-07-09 12:31:50 +01:00

103 lines
2.8 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_ramc_read(0, AT91_DDRSDRC_LPR);
lpr = saved_lpr & ~AT91_DDRSDRC_LPCB;
at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr | AT91_DDRSDRC_LPCB_SELF_REFRESH);
return saved_lpr;
}
#define sdram_selfrefresh_disable(saved_lpr) at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr)
#elif defined(CONFIG_ARCH_AT91SAM9G45)
#include <mach/at91sam9_ddrsdr.h>
/* We manage both DDRAM/SDRAM controllers, we need more than one value to
* remember.
*/
static u32 saved_lpr1;
static inline u32 sdram_selfrefresh_enable(void)
{
/* Those tow values allow us to delay self-refresh activation
* to the maximum. */
u32 lpr0, lpr1;
u32 saved_lpr0;
saved_lpr1 = at91_ramc_read(1, AT91_DDRSDRC_LPR);
lpr1 = saved_lpr1 & ~AT91_DDRSDRC_LPCB;
lpr1 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
lpr0 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
/* self-refresh mode now */
at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
at91_ramc_write(1, AT91_DDRSDRC_LPR, lpr1);
return saved_lpr0;
}
#define sdram_selfrefresh_disable(saved_lpr0) \
do { \
at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0); \
at91_ramc_write(1, AT91_DDRSDRC_LPR, saved_lpr1); \
} while (0)
#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.
*/
#warning Assuming EB1 SDRAM controller is *NOT* used
#endif
static inline u32 sdram_selfrefresh_enable(void)
{
u32 saved_lpr, lpr;
saved_lpr = at91_ramc_read(0, AT91_SDRAMC_LPR);
lpr = saved_lpr & ~AT91_SDRAMC_LPCB;
at91_ramc_write(0, AT91_SDRAMC_LPR, lpr | AT91_SDRAMC_LPCB_SELF_REFRESH);
return saved_lpr;
}
#define sdram_selfrefresh_disable(saved_lpr) at91_ramc_write(0, AT91_SDRAMC_LPR, saved_lpr)
#endif