On 3/14/24 01:56, Yangyu Chen wrote:

quoted

Hi,

Thanks for the review comments. After thinking about it for a while,
I think we don't need to change it as we have changed the help
message which deleted the "K210". And the dts on k210.dtsi shows
mmu-type is riscv.none, I think if someone noticed this would know
why it fails to boot on the S-Mode MMU Kernel on K210. The only
special thing for ARCH_CANAAN is that a loader.bin will be built
when M-Mode is on arch/riscv/Makefile. However, Canaan has no other
M-Mode chips except for K210. So I think we don't need to change
it.

You completely lost me here. I do not understand what you are trying to say.

quoted

Another reason is that SOC_CANAAN for K210 is somehow hard to change.
If we continue using SOC_CANAAN for K210 but not for other Canaan
SoCs such as K230, it will cause some confusion to users. If we
rename SOC_CANAAN to SOC_CANAAN_K210, it will change many drivers
in many subsystems like my patch v5 [1]. So I don't think we need
to fix it.


If we don't change it, A concern for this is that some drivers for
K210 will be built when SOC_CANAAN=y and if we add this to defconfig,
all riscv builds will also build some K210 drivers even on MMU. But
I think this will not be a problem just need some memory/storage
for a slightly bigger kernel. Also, we will enable some new configs
in defconfig when a new soc gets supported, it's normal for K210
SoC drivers.

Thus, I think we don't need to change it. If you have some other
opinions, please let me know.

1) Rename SOC_CANAAN to SOC_CANAAN_K210 and use that for any conditional code or
driver selection that is specific to the K210, which is what's done now.
2) Create a "new" SOC_CANAAN config and make SOC_CANAAN_K210 depend on it and on
!MMU

You could also add SOC_CANAAN_K230 if needed and make it depend on SOC_CANAAN &&
MMU.

With that, dirvers common to both the K210 and K230 can easilly be selected and
selecting SOC_CANAAN will end up either building for the K230 or the K210,
depending on MMU being set or not.

That's my 2 cents. Feel free to ignore. I am not involved that much with riscv
these days and I am far too busy with other kernel areas to be of any help. But
I really think that allowing building the K210 when MMU is enabled and "hoping
that the user understand his mistake" is not a great approach.

-- 
Damien Le Moal
Western Digital Research