Re: [PATCH v7 2/3] DT/arm,gic-v3-its: add reset-on-suspend property
From: Mark Rutland <mark.rutland@arm.com>
Date: 2018-03-01 11:35:04
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On Wed, Feb 28, 2018 at 09:48:19PM -0800, Derek Basehore wrote:
quoted hunk ↗ jump to hunk
This adds documentation for the new reset-on-suspend property. This property enables saving and restoring the ITS for when it loses state in system suspend. Signed-off-by: Derek Basehore <redacted> --- .../devicetree/bindings/interrupt-controller/arm,gic-v3.txt | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt index 0a57f2f4167d..dfd1b9b838cd 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt@@ -78,6 +78,11 @@ These nodes must have the following properties: Optional: - socionext,synquacer-pre-its: (u32, u32) tuple describing the untranslated address and size of the pre-ITS window. +- reset-on-suspend: Boolean property. Indicates that the ITS loses power + on suspend to memory (via PSCI_SYSTEM_SUSPEND). Registers and data within + the ITS will be the same as before probe (PSCI FW does not restore state).
What does 'before probe' mean? Perhaps 'at reset'? Is the state well-defined, or might there be some bits that differ from boot-to-boot? Otherwise, this generally looks ok.
+ Any state stored in external memory is maintained (such as collection + tables stored in external memory).
This a property of PSCI_SYSTEM_SUSPEND not corrupting memory state, so this need not be stated here. This can go. Thanks, Mark.