On 01/22/2018 12:09 PM, JeffyChen wrote: > Hi Randy, > > On 01/22/2018 10:15 AM, JeffyChen wrote: >> Hi Randy, >> >> On 01/22/2018 09:18 AM, Randy Li wrote: >>>> >>> Also the power domain driver could manage the clocks as well, I would >>> suggest to use pm_runtime_*. >> >> actually the clocks required by pm domain may not be the same as what we >> want to control here, there might be some clocks only be needed when >> accessing mmu registers. >> >> but i'm not very sure about that, will confirm it with Simon Xue. > > confirmed with Simon, there might be some iommus don't have a pd, and We use the pd to control the NIU node(not on upstream), without a pd or fake pd, none of the platform would work. > the CONFIG_PM could be disabled.I am hard to believe a modern platform can work without that. > > so it might be better to control clocks in iommu driver itself.I won't insist how the version of the iommu patch on the upstream, I just post an idea here. The version for kernel 4.4 is under internal review, the implementation has been modified many times. I would suggest the managing clocks in pd is a more easy way and don't need to spare those thing in two places. > > > _______________________________________________ > Linux-rockchip mailing list > Linux-rockchip at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-rockchip > -- Randy Li
