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linux-next/arch/arm/mach-at91/pm.h

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/*
* AT91 Power Management
*
* Copyright (C) 2005 David Brownell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __ARCH_ARM_MACH_AT91_PM
#define __ARCH_ARM_MACH_AT91_PM
#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_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
#endif