Re: [PATCH V4 2/6] iommu/arm-smmu: Add pm_runtime/sleep ops

From: Vivek Gautam
Date: Wed Jul 12 2017 - 23:58:03 EST

On 07/13/2017 04:31 AM, Stephen Boyd wrote:
On 07/12, Stephen Boyd wrote:
On 07/06, Vivek Gautam wrote:
From: Sricharan R <sricharan@xxxxxxxxxxxxxx>

The smmu needs to be functional only when the respective
master's using it are active. The device_link feature
helps to track such functional dependencies, so that the
iommu gets powered when the master device enables itself
using pm_runtime. So by adapting the smmu driver for
runtime pm, above said dependency can be addressed.

This patch adds the pm runtime/sleep callbacks to the
driver and also the functions to parse the smmu clocks
from DT and enable them in resume/suspend.

Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
Signed-off-by: Archit Taneja <architt@xxxxxxxxxxxxxx>
[vivek: Clock rework to loop over clock names data]
Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx>
General comment, we have a bulk clk API now, but I guess we
failed to add the clk_bulk_prepare_enable() API that could be
used here. Perhaps you can add that API and then use it here to
reduce lines of code.

Sure, will use the bulk clock APIs to handle the clocks.

Best regards

Bjorn just sent a patch for that API an hour ago.

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