On Tue, 2022-03-29 at 11:01 +0200, Marek Vasut wrote:
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On 3/29/22 04:49, Ye Li wrote:
Hi,
If you change the ROM API driver, that will break our design. You can try to overwrite spl_romapi_get_uboot_base for your board only.
Since there are no users which boot from flexspi upstream, this design can still be fixed such that it does not require different flash.bin for different boot media, but rather one flash.bin works on all boot media. I think that is much better.
Your flash.bin can work on flexspi because you manually program the flexspi configurations header.
Sure, the header content is described in the MX8MP RM Rev. 1 06/2021 "6.1.5.3.1 FlexSPI Configuration Block", this has nothing to do with this patch.
But once you want to upgrade the flash.bin, flexspi configurations will also be erased due to the block size. Then you have to reprogram the configurations with flash.bin. So most of our customers add the flexspi configurations to flash.bin head. They don't use so called one image for both SD and flexspi.
There are no upstream users of flexspi right now, see above.
As the spl_romapi_get_uboot_base is defined to weak. It is better to overwrite this function for your particular usage.
I would much rather prefer to have one flash.bin which works on both SD card and FlexSPI, on all iMX8M, that is far less confusing. And since there are no upstream users of flexspi boot so far, this is how it can still be implemented, consistently.
I can think out 3 drawbacks using this one flash.bin for flexspi:
1. The flexspi configuration header will be erased when you update the flash.bin to flexspi device. In a common usage, this header will combine with flash.bin to a final boot image which is not same with SD. 2. How can users update u-boot.itb only if using this one flash.bin? With the same offset of SD, it causes the u-boot.itb locates at a offset not block aligned.
3. Not all iMX8M can support this one flash.bin. 8MM and 8MQ have different IVT. Their flexspi IVT can't work for SD/eMMC.
Best regards, Ye Li
If downstream wants to have multiple flash.bin, one for each boot media, that's up to downstream.
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