On Mon, Jul 12, 2021 at 11:15 PM Tom Rini trini@konsulko.com wrote:
On Mon, Jul 12, 2021 at 01:36:14PM +0800, Bin Meng wrote:
On Mon, Jul 12, 2021 at 1:21 PM Reuben Dowle reuben.dowle@4rf.com wrote:
I submitted an almost identical patch. See https://github.com/u-boot/u-boot/commit/eb39d8ba5f0d1468b01b89a2a464d18612d3...
This patch eventually had to be reverted (https://github.com/u-boot/u-boot/commit/5675ed7cb645f5ec13958726992daeeed16f...), because it was causing issues on some platforms that had FIT on 32 bit boundary. However I continue to use it in production code, as without it the boot on my platform aborts.
I don't have time to investigate why this was happening, but you need to check this code won't just cause exactly the same faults.
Thanks for your information.
+Marek who did the revert
The revert commit message says:
"The commit breaks booting of fitImage by SPL, the system simplyhangs. This is because on arm32, the fitImage and all of its content can be aligned to 4 bytes and U-Boot expects just that."
I don't understand this. If an address is aligned to 8, it is already aligned to 4, so how did this commit make the system hang on arm32?
I think this had something to do with embedding contents somewhere in the image? There is a thread on the ML from then but I don't know how informative it will end up being.
Note, as I indicated in this patch, now with libfdt 1.6.1, the alignment to 8 byte is a must-have. So we have to do such alignment anyway.
@Tom may fill in why libfdt commit commit 5e735860c478 ("libfdt: Check for 8-byte address alignment in fdt_ro_probe_()") was made to have the 8-byte alignment requirement.
Note that it's not so much since libfdt 1.6.1 but that since always the device tree has required 8 byte alignment. It's just that on 32bit platforms 4-but-not-8 byte alignment tends to not be fatal but on 64bit platforms it is.
But with libfdt v1.6.1 commit 5e735860c478 ("libfdt: Check for 8-byte address alignment in fdt_ro_probe_()"), now this is fatal error if DT address is not 8-bytes aligned, as that commit adds a check in fdt_ro_probe_().
Regards, Bin