On Sun, 20 Oct 2024 15:06:46 +0530 Parthiban <parthiban@xxxxxxxxxxx> wrote: Hi, > Am currently adding support for Allwinner A133 SoC based on A100. Many thanks for picking this up, but what do you mean exactly by "adding support"? As you probably have seen, there is already some basic support for the A100 in the tree, and since we assume that both SoCs are basically identical, there wouldn't be too much left to do, would there? For reference, there is some leftover patch series from the original A100 upstreaming attempt, which you could rebase and rework: https://lore.kernel.org/linux-arm-kernel/cover.1604988979.git.frank@xxxxxxxxxxxxxxxxx/ I haven't checked in a while, but some patches in there have either been merged or are superseded by other patches, and I guess the others need at least a rebase, but it's certainly something worthwhile to work on. > Based on the [1], > A100 and A133 uses same IP across. But there is no public available datasheet or > user manual for A100. Indeed there has never been, and back then we relied on information provided by those Allwinner employees sending the patches. For now we assume that the A133 manual describes the A100 as well. > Should A100 kept as base and A133 dtsi needs to added on top or A133 can be duplicated > into a new devicetree? As far as we know, the A133 is the better bin of the A100, so they should be identical from the software perspective. This seems to be similar to the H616/H313 situation. At some point the A100 totally disappeared from Allwinner's documentation (in an almost "Orwellian 1984 fashion"), and they only mention the A133 ever since. So, since the A100 is already in, and was the first one, I'd say: - Keep using an allwinner,sun50i-a100 prefix for any compatible string. Rationale: it's the base model, and was the first one, and we have compatible strings with that in, so we should keep using that for consistency. - There is no need for any kind of a133.dtsi, since they are probably identical. - If you add a board with an A133, use that name in the root compatible string, but include the a100.dtsi. See the H616/H313/H618 situation, for instance as in sun50i-h618-transpeed-8k618-t.dts. Hope that helps, and thanks for your efforts on improving support for that chip! Please come back to the #linux-sunxi IRC channel on OFTC, there is someone (MasterR3C0RD) actively working on some A133 board as well, and he even has a working DRAM driver for U-Boot. So you should coordinate any upstreaming efforts. Cheers Andre > > [1]: https://linux-sunxi.org/Linux_mainlining_effort#Status_Matrix >
