From d3832e8fe1b214ec62424eac36cfda9fc56d21b3 Mon Sep 17 00:00:00 2001 From: Domen Puncer Date: Mon, 16 Apr 2007 14:00:13 +0200 Subject: [PATCH] [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 Acked-by: Grant Likely --- Makefile | 5 +++++ board/icecube/icecube.c | 49 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 54 insertions(+) diff --git a/Makefile b/Makefile index 84b49fe1b3..8e551eb555 100644 --- a/Makefile +++ b/Makefile @@ -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" ; \ diff --git a/board/icecube/icecube.c b/board/icecube/icecube.c index 700c9d9323..2960998434 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; } -- 2.30.2