On 3/15/07, Domen Puncer domen.puncer@telargo.com wrote:

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

This looks pretty straight forward.

My only comment is that psc2_4 is probably used as GPIO instead of power control by some users (The lite5200 is an eval board after all). Maybe wrap the code with #ifdef CONFIG_LITE5200B_PM (instead of CONFIG_LITE5200B) so that it can be easily compiled out.

Also, '//' style comments should be changed to '/* */'

Otherwise; Acked-by: Grant Likely grant.likely@secretlab.ca

g.

---

board/icecube/icecube.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+)

Index: u-boot.git/board/icecube/icecube.c

--- u-boot.git.orig/board/icecube/icecube.c +++ u-boot.git/board/icecube/icecube.c @@ -42,6 +42,54 @@ #include "mt48lc16m16a2-75.h" # endif #endif

+#ifdef CONFIG_LITE5200B +/* 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 +256,8 @@ long int initdram (int board_type) __asm__ volatile ("sync"); }

•   lite5200b_wakeup();
  

•   return dramsize + dramsize2;
  

}