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

[Grant Likely]

On 4/3/07, Domen Puncer <domen.puncer at 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.

Looks good; almost there.  Only one thing missing... you need to add
your "Signed-off-by" line.  :-)  See Documentation/SubmittingPatches
in the Linux source tree.  (You can just reply to this message, and
whoever merges the patch will add the line to the commit message)

Acked-by: Grant Likely <grant.likely at secretlab.ca>

Stefan; since there is no 5200 custodian, can you please pick up this
patch once Domen sends a Signed-of-by replay?

Cheers,
g.

>
>
> ---
> On 26/03/07 10:08 -0600, Grant Likely wrote:
> > On 3/15/07, Domen Puncer <domen.puncer at 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 at secretlab.ca>
> >
>
> OK. This one should be better:
>
>  Makefile                |    5 ++++
>  board/icecube/icecube.c |   49 ++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 54 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 +42,53 @@
>  #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;
>  }
>
> Index: u-boot.git/Makefile
> ===================================================================
> --- u-boot.git.orig/Makefile
> +++ u-boot.git/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" ; \
>


-- 
Grant Likely, B.Sc. P.Eng.
Secret Lab Technologies Ltd.
grant.likely at secretlab.ca
(403) 399-0195