Re: [PATCH V2 1/3] iommu/arm-smmu: Add pm_runtime/sleep ops
From: Mark Rutland <hidden>
Date: 2017-02-08 13:52:53
Also in:
linux-arm-kernel, linux-arm-msm, linux-iommu
From: Mark Rutland <hidden>
Date: 2017-02-08 13:52:53
Also in:
linux-arm-kernel, linux-arm-msm, linux-iommu
On Wed, Feb 08, 2017 at 07:15:37PM +0530, Sricharan wrote:
quoted
Clocks are not architectural, so it only makes sense to associate them with an implementation-specific compatible string. There's also nook, it for this the QCOM specific implementation binding is tried(going to).quoted
guarantee that different microarchitectures have equivalent internal clock domains - I'm not sure if "the SMMU's underlying bus access" is meant to refer to accesses *by* the SMMU, i.e. page table walks, accesses *through* the SMMU by upstream masters, or bothIn the above QCOM case, it is actually both. Its the same path for both the page table walker and upstream masters.quoted
differences are rather significant. I'd also note that an MMU-500 configuration may have up to *33* clocks. Either way, the QCOM implementation deserves its own compatible if only for the sake of the imp-def gaps in the architecture (e.g. FSR.SS behaviour WRT to IRQs as touched upon in the other thread).Ok, slightly unclear, so you mean then *clocks* are not good enough reason to have a new compatible ?
I beleive Robin's point was even if the clocks didn't matter, there are other reasons we should have the QCOM-specific compatible string. So we should have one regardless. Thanks, Mark.