Re: [PATCH 0/7] MIPS DMA coherence fixes

[Jiaxun Yang]

> 2023年2月21日 19:46，Robin Murphy <robin.murphy@xxxxxxx> 写道：
> 
> On 2023-02-21 18:15, Jiaxun Yang wrote:
>>> 2023年2月21日 17:54，Christoph Hellwig <hch@xxxxxx> 写道：
>>> 
>>> Can you explain the motivation here?  Also why riscv patches are at
>>> the end of a mips fіxes series?
>> Ah sorry for any confusion.
>> So the main purpose of this patch is to fix MIPS’s broken per-device coherency.
>> To be more precise, we want to be able to control the default coherency for all devices probed from
>> devicetree in early boot code.
> 
> Including the patch which actually does that would be helpful. As it is, patches 4-7 here just appear to be moving an option around for no practical effect.

Well the affect is default coherency of devicetree probed devices are now following dma_default_coherent
instead of a static Kconfig option. For MIPS platform, dma_default_coherent will be determined by boot code.

Thanks
- Jiaxun