Hi Chris,
On 12.05.21 23:20, Chris Packham wrote:
On Wed, May 12, 2021 at 8:06 PM Stefan Roese <s...@denx.de> wrote:
On 12.05.21 09:59, Chris Packham wrote:
On Wed, May 12, 2021 at 7:18 PM Stefan Roese <s...@denx.de> wrote:
Currently, building U-Boot for x530 fails since the SPL image is too
big.
Currently? It's working for me on master. Are there upcoming mvebu
changes that push us over the limit?
Yes, I'm working on a pull request right now. Some enhancements to the
SPI driver are most likely responsible for the code increase.
This patch reduces the SPL size by changing the following Kconfig
options:
Enable CONFIG_SPL_TINY_MEMSET
Disable CONFIG_SPI_FLASH_BAR
By disabling CONFIG_SPI_FLASH_BAR, the tiny SPI NOR framework can be
used.
I've got a nagging feeling I needed CONFIG_SPI_FLASH_BAR for some
reason. Possibly for some alternate part we were looking at, on the
other hand it could also be from the db88f6820-amc board which I based
the initial defconfig on.
Looking at what CONFIG_SPI_FLASH_BAR does I think we should be safe.
We only fit 16MiB parts and aren't likely to start fitting bigger
parts unless all the spi-nor vendors decide to stop making ones
<16MiB.
Please note that there are better ways to handle the > 16MiB SPI
NOR issue. E.g. by using 3 vs 4 byte commands and Serial Flash
Discoverable Parameters (SFDP) parsing, which is supported in
U-Boot since quite some time. I did not use CONFIG_SPI_FLASH_BAR
for a longer time now IIRC.
I think (but am not sure) that the 4 byte command mode upsets the
bootrom when booting from spi flash. On and off I've hit a problem on
the db-88f6820-amc which does have a 32MiB flash fitted where the
bootrom can't fetch the first boot stage on reboot after booting linux
(for some kernel versions). Power cycling resolves the problem. I
think this might be because the bootrom only speaks the 3 byte
protocol and once the chip is put into 4 byte mode the bootrom lacks
the ability to change back. None of this affects the x530 so there is
no problem with this change. I'm just putting this out there for
future mailing list readers.
Yes, this is known issue. Or it was a known issue. Newer version support
the stateless 4-byte opcodes, which don't configure the SPI NOR into
4-byte mode. This resolves this problem with the bootrom AFAIR.
Thanks,
Stefan
