[U-Boot] [PATCH] ppc4xx: Don't fixup NOR flash node size on Ebony

[Wolfgang Denk <wd@denx.de>]

Dear Stefan Roese,

In message <1284555484-27269-1-git-send-email-sr@denx.de> you wrote:
> Don't update size in "reg" property of NOR FLASH device tree nodes.
> This leads to a problem with this NOR flash setup, where
> chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash.
> And with this fixup-code, the size of the NOR flash node is changed
> from 512KiB to 1MiB which leads to a crash in the Linux MTD driver.
> 
> Signed-off-by: Stefan Roese <sr@denx.de>
> Cc: Detlev Zundel <dzu@denx.de>
> ---
>  include/configs/ebony.h |    8 ++++++++
>  1 files changed, 8 insertions(+), 0 deletions(-)
> 
> diff --git a/include/configs/ebony.h b/include/configs/ebony.h
> index 10f425d..eb58240 100644
> --- a/include/configs/ebony.h
> +++ b/include/configs/ebony.h
> @@ -117,6 +117,14 @@
>  #define CONFIG_SYS_FLASH_ADDR0         0x5555
>  #define CONFIG_SYS_FLASH_ADDR1         0x2aaa
>  #define CONFIG_SYS_FLASH_WORD_SIZE     unsigned char
> +/*
> + * Don't update size in "reg" property of NOR FLASH device tree nodes.
> + * This leads to a problem with this NOR flash setup, where
> + * chip-select 0 is connected to 512KiB SRAM *and* 512KiB NOR flash.
> + * And with this fixup-code, the size of the NOR flash node is changed
> + * from 512KiB to 1MiB which leads to a crash in the Linux MTD driver.
> + */
> +#undef CONFIG_FDT_FIXUP_NOR_FLASH_SIZE

Sorry, but NAK.


Even if connected to the same chip select, NOR flash and SRAM are
different devices, which are described by different properties in the
device tree and which have separate addresses and sizes.

The "reg" property of NOR FLASH device tree nodes *should* be updated
with the correct size of the NOR flash as determined by the CFI
driver; on this board, this should be 512 KiB.

Both the bd_info command and the device tree should report a NOR flash
size of 512 KiB.

The SRAM size is completely independent of that. As we don't provide
auto-sizing for the sram, the board config file should contain (read:
needs to get fixed to contain) the correct CONFIG_SYS_SRAM_BASE and
CONFIG_SYS_SRAM_SIZE settings (with CONFIG_SYS_SRAM_SIZE = 512 KiB).

Both the bd_info command and the device tree should report a SRAM size
of 512 KiB.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Any sufficiently advanced technology is indistinguishable from magic.
                                                   - Arthur C. Clarke