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| author | Domen Puncer <domen.puncer@telargo.com> | 2007-04-16 14:00:13 +0200 |
|---|---|---|
| committer | Stefan Roese <sr@denx.de> | 2007-04-16 14:00:13 +0200 |
| commit | d3832e8fe1b214ec62424eac36cfda9fc56d21b3 (patch) | |
| tree | 09f5fe519eb1f26502dd3be4882d41010041f903 /board/icecube/icecube.c | |
| parent | 7882751c78b7ecabfd49b0eff8de27661c71f16c (diff) | |
| download | u-boot-imx-d3832e8fe1b214ec62424eac36cfda9fc56d21b3.zip u-boot-imx-d3832e8fe1b214ec62424eac36cfda9fc56d21b3.tar.gz u-boot-imx-d3832e8fe1b214ec62424eac36cfda9fc56d21b3.tar.bz2 | |
[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>
Diffstat (limited to 'board/icecube/icecube.c')
| -rw-r--r-- | board/icecube/icecube.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/board/icecube/icecube.c b/board/icecube/icecube.c index 700c9d9..2960998 100644 --- a/board/icecube/icecube.c +++ b/board/icecube/icecube.c @@ -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; } |