On Thursday 20 August 2020 10:51:28 Pali Rohár wrote:
On Thursday 20 August 2020 10:17:55 Stefan Roese wrote:
On 20.08.20 09:40, Pali Rohár wrote:
On Thursday 20 August 2020 07:02:18 Stefan Roese wrote:
Can't you just use "mtdparts=" kernel cmdline parameter instead to pass the MTD layout to the kernel?
Maybe it is possible too, I have not tried it.
I thought that more common is to update DTS file by uboot when loading kernel as it is already done e.g. for ethernet MAC address on Espressobin.
Updating the MAC address is very common, yes. But passing the MTD partition layout via the mtdparts= cmdline is also very common and used very frequently. From my experience, its the defacto recommended method to pass this info and also easier than generating these DTS lines via some code.
Please take a look at the mtdparts U-Boot command and its usage in other targets.
Also I see that uboot has function fdt_fixup_mtdparts() via CONFIG_FDT_FIXUP_PARTITIONS option which do this, but uses uboot MTD code which IIRC cannot initialize SPI NOR.
Why not?
I had an impression that U-Boot does not support.
SPI NOR is also integrated into the U-Boot MTD world as well. Please see this GARDENA MT7688 target, which uses SPI NOR & SPI NAND:
Ok, I'm going to look at it.
With following config
CONFIG_MTD=y CONFIG_CMD_MTD=y CONFIG_CMD_MTDPARTS=y CONFIG_SPI_FLASH_MTD=y CONFIG_MTDIDS_DEFAULT="nor0=nor0"
I get following result:
=> mtd list List of MTD devices: No MTD device found => mtdparts Device nor0 not found! => sf probe SF: Detected w25q32dw with page size 256 Bytes, erase size 4 KiB, total 4 MiB => mtdparts => mtd list List of MTD devices: * nor0 - type: NOR flash - block size: 0x1000 bytes - min I/O: 0x1 bytes - 0x000000000000-0x000000400000 : "nor0"
So main problem is that MTD does not work until I call 'sf probe' in uboot command line.