[PATCH] icecube/lite5200b: wakeup from low-power support

U-Boot part of Lite5200b low power mode support.
Puts SDRAM out of self-refresh and transfers control to
address saved at physical 0x0.

Signed-off-by: Domen Puncer <domen.puncer@telargo.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Domen Puncer 2007-04-16 14:00:13 +02:00 committed by Stefan Roese
parent 7882751c78
commit d3832e8fe1
2 changed files with 54 additions and 0 deletions

View File

@ -430,6 +430,7 @@ inka4x0_config: unconfig
@$(MKCONFIG) inka4x0 ppc mpc5xxx inka4x0
lite5200b_config \
lite5200b_PM_config \
lite5200b_LOWBOOT_config: unconfig
@mkdir -p $(obj)include
@mkdir -p $(obj)board/icecube
@ -438,6 +439,10 @@ lite5200b_LOWBOOT_config: unconfig
@ echo "... DDR memory revision"
@ echo "#define CONFIG_MPC5200" >>$(obj)include/config.h
@ echo "#define CONFIG_LITE5200B" >>$(obj)include/config.h
@[ -z "$(findstring _PM_,$@)" ] || \
{ echo "#define CONFIG_LITE5200B_PM" >>$(obj)include/config.h ; \
echo "... with power management (low-power mode) support" ; \
}
@[ -z "$(findstring LOWBOOT_,$@)" ] || \
{ echo "TEXT_BASE = 0xFF000000" >$(obj)board/icecube/config.tmp ; \
echo "... with LOWBOOT configuration" ; \

View File

@ -42,6 +42,53 @@
#include "mt48lc16m16a2-75.h"
# endif
#endif
#ifdef CONFIG_LITE5200B_PM
/* u-boot part of low-power mode implementation */
#define SAVED_ADDR (*(void **)0x00000000)
#define PSC2_4 0x02
void lite5200b_wakeup(void)
{
unsigned char wakeup_pin;
void (*linux_wakeup)(void);
/* check PSC2_4, if it's down "QT" is signaling we have a wakeup
* from low power mode */
*(vu_char *)MPC5XXX_WU_GPIO_ENABLE = PSC2_4;
__asm__ volatile ("sync");
wakeup_pin = *(vu_char *)MPC5XXX_WU_GPIO_DATA_I;
if (wakeup_pin & PSC2_4)
return;
/* acknowledge to "QT"
* by holding pin at 1 for 10 uS */
*(vu_char *)MPC5XXX_WU_GPIO_DIR = PSC2_4;
__asm__ volatile ("sync");
*(vu_char *)MPC5XXX_WU_GPIO_DATA_O = PSC2_4;
__asm__ volatile ("sync");
udelay(10);
/* put ram out of self-refresh */
*(vu_long *)MPC5XXX_SDRAM_CTRL |= 0x80000000; /* mode_en */
__asm__ volatile ("sync");
*(vu_long *)MPC5XXX_SDRAM_CTRL |= 0x50000000; /* cke ref_en */
__asm__ volatile ("sync");
*(vu_long *)MPC5XXX_SDRAM_CTRL &= ~0x80000000; /* !mode_en */
__asm__ volatile ("sync");
udelay(10); /* wait a bit */
/* jump back to linux kernel code */
linux_wakeup = SAVED_ADDR;
printf("\n\nLooks like we just woke, transferring control to 0x%08lx\n",
linux_wakeup);
linux_wakeup();
}
#else
#define lite5200b_wakeup()
#endif
#ifndef CFG_RAMBOOT
static void sdram_start (int hi_addr)
{
@ -208,6 +255,8 @@ long int initdram (int board_type)
__asm__ volatile ("sync");
}
lite5200b_wakeup();
return dramsize + dramsize2;
}