[PATCH v3 0/3] power: reset: Add NVMEM recorder provider for PSCRR
From: Faruque Ansari <hidden>
Date: 2026-09-14 04:39:20
Also in:
linux-arm-msm, linux-devicetree, linux-watchdog, lkml
The PSCRR framework[1] currently does not provide a recorder provider capable of persisting power state change reasons across power cycles. This series extends the PSCRR framework[1] with support for an NVMEM-cell recorder provider, integrating PSCRR-recorded power state change reasons with the NVMEM subsystem. The recorder writes the power state change reason into a small NVMEM cell (e.g. a PMIC SDAM byte or RTC scratch register) before shutdown or reset, so the cause survives a power cycle and is available via /sys/kernel/pscrr/ on the next boot. Only the NVMEM-cell provider is included here. The PMIC hardware-register provider will be submitted as a separate series. [1] https://lore.kernel.org/lkml/20260731095959.296056-1-o.rempel@pengutronix.de/ (local) --- Changes in v3: - Drop unnecessary nvmem_cell_get_size() and core compatibility detection changes because the layout now owns the compatible. - Patch 1/3 (dt-bindings): Move compatible from the cell to the nvmem-layout node, relocate binding to nvmem/layouts/, and simplify the cell to a plain reg/bits child. - Drop the trailing "binding" from the subject, as suggested by Krzysztof. - Patch 2/3 (driver): Convert pscrr-nvmem from a consumer-based platform driver to an nvmem_layout_driver that directly manages its cell. - Patch 3/3 (dts): Update DTS to place compatible on the layout node, add bits to reboot_reason_persist, and remove the separate reboot-reason consumer node. - Link to v2: https://patch.msgid.link/20260819-pscrr-provider-v2-0-9072383e0f4d@oss.qualcomm.com Changes in v2: - Add reviewers to To/Cc list. - Update patch 1/4: * Rename DT node from pscr-reason to reboot-reason. * Update DT binding example to use fixed-layout NVMEM layout. * Add reboot_reason_persist NVMEM cell under fixed-layout. * Update Qualcomm DTS example accordingly. - Update patch 2/4 based on Uwe Kleine-König feedback: * Remove unnecessary #include <linux/mod_devicetable.h> - Link to v1: https://lore.kernel.org/all/20260817-pscrr-provider-v1-0-88a318c13d41@oss.qualcomm.com/ (local) --- Faruque Ansari (3): dt-bindings: nvmem: layouts: Add PSCRR NVMEM layout power: reset: Add PSCRR NVMEM recorder arm64: dts: qcom: lemans: Add PSCRR NVMEM recorder node .../bindings/nvmem/layouts/nvmem-layout.yaml | 1 + .../bindings/nvmem/layouts/pscrr-nvmem.yaml | 87 +++++++ MAINTAINERS | 1 + arch/arm64/boot/dts/qcom/lemans-pmics.dtsi | 11 + drivers/power/reset/pscrr/Kconfig | 14 ++ drivers/power/reset/pscrr/Makefile | 1 + drivers/power/reset/pscrr/pscrr-nvmem.c | 269 +++++++++++++++++++++ 7 files changed, 384 insertions(+) --- base-commit: be461b2185ea3ff6d9c92deedcee0a62a57e1332 change-id: 20260806-pscrr-provider-b9f8f451701e Best regards, -- Faruque Ansari [off-list ref]