[U-Boot] [PATCH v2] imximage: Remove overwriting of flash_offset

[Stefano Babic]

On 23/02/2012 09:50, Dirk Behme wrote:
> The flash header supports different flash offsets for different
> boot devices. E.g. parallel NOR or OneNAND use a different offset
> than FLASH_OFFSET_STANDARD (== 0x400).
> 
> The flash offset is correctly read from the configuration in
> parse_cfg_cmd(). But is then overwritten wrongly in set_imx_hdr_v1/2().
> 
> Fix this by removing this overwriting. Use the flash offset
> correctly read from the configuration, instead.
> 
> If there is no flash_offset read from the configuration file, i.e.
> the BOOT_FROM tag is missing, exit with an error message.
> 
> Signed-off-by: Dirk Behme <dirk.behme at de.bosch.com>
> CC: Jason Liu <liu.h.jason at gmail.com>
> CC: Stefano Babic <sbabic at denx.de>
> ---

Tested on ima-mx53 with MX53 (header V2), booting from NOR.

Tested-by: Stefano Babic <sbabic at denx.de>


Dirk,

apart this patch that fixes in any case a wrong offset in header, I have
investigated in more detail this issue. The bug sets a wrong value in
the boot_data.start field that inform the processor which is the start
address of the image to be copied into the RAM. All other fields are
still correct.

However, if we boot from NOR we have a XIP device and we do not need
this first copy into the RAM. We could skip it if we set
CONFIG_SYS_TEXT_BASE to point to a region in the NOR flash, as it is
usually done when booting from NOR (see for example PowerPc boards).
I understand that this is the reason why my board has always booted,
while yours not. Is it right ? Where do you set CONFIG_SYS_TEXT_BASE ?

As optimization, we could also avoid that the processor starts to copy
the image by setting boot_data.size=0 in the header when NOR device is
set, but only if we are sure that no copy into RAM is required.

Best regards,
Stefano Babic

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