Hi Adam,
On Sunday 27 August 2017 08:31 PM, Adam Ford wrote:
I was trying to enable MTD Partitions to make loading the Kernel and FS easier from within U-Boot
The da850evm spi-flash partitions in Linux show
"U-Boot-SPL" @ offset 0, size 64K "U-Boot"; @ offset 0x00010000, size 512K "U-Boot-Env"; @ offset 0x00090000
According to board/davinci/da8xxevm/README.da850, we support AIS image format for SPI boot. This is a single image containing SPL and U-Boot.
Given this, I think having separate partitions for SPL and U-Boot does not make sense since thats not how its going to be used.
However U-Boot shows the following:
CONFIG_SYS_SPI_U_BOOT_OFFS 0x8000 which would make the SPL partition 32K. CONFIG_SYS_SPI_U_BOOT_SIZE 0x40000 and the size of U-boot 256K instead of 512k.
CONFIG_ENV_SIZE (64 << 10) CONFIG_ENV_OFFSET (512 << 10) which is 0x80000 instead of Linux's 0x90000
It seems to me like the U-Boot and Linux should try and synchronize their partitions tables.
Right.
For people who want to burn Linux into the SPI flash it seems there there should be some consistency. I tried making the U-boot settings match the Linux ones, but it seems to hang between SPL and U-Boot, so I think the U-Boot offset in Linux might need to match U-Boot. Can you guys make some recomendations as to which is correct?
I have not tried it, but looks like the partitions we need are
"SPL/U-Boot AIS" @ offset 0, size 512K "U-Boot Environment" @ offset 512K, size 64K "Kernel/Spare" @ offset 576K, size 7552K "Mac Address" @ offset 8128K, size 64K (read only)
With an 8M flash, I think its futile to try to fit a modern filesystem on the flash.
If you are using DT boot, we cannot really change the partitions in device-tree because of DT backward-compatibility requirements. But we can fix da850evm_spiflash_part[] table in arch/arm/mach-davinci/board-da850-evm.c.
To help DT boot, we can pass fixed up mtdparts through environment variables. Something like what is done in 3f18ff07c81b ("ARM: keystone: Pass SPI MTD partition table via kernel command line").
Thanks, Sekhar