[PATCH v2 2/4] firmware: xilinx: Release all peripheral devices from firmware
From: Jay Buddhabhatti <hidden>
Date: 2026-07-24 09:53:28
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Subsystem:
the rest · Maintainer:
Linus Torvalds
During a kexec restart, only the kernel is reloaded while devices allocated in firmware persist, causing state mismatches between the kernel and firmware. Introduce PM_DEV_ALL_PERIPH node ID (0x18224FFFU) to release all peripheral devices during kexec. On graceful restarts, this happens in zynqmp_firmware_shutdown(). On crash kernel restarts, it happens in zynqmp_firmware_probe() of the reloaded kernel. Releasing all peripherals depends on firmware support for the PM_DEV_ALL_PERIPH node ID. On firmware that does not implement it (the feature check reports a version below PM_API_VERSION_3) the release is skipped and a warning such as "Bulk device release is not supported by firmware" is logged, e.g. on Versal NET firmware that predates this API. Signed-off-by: Jay Buddhabhatti <redacted> Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com> Reviewed-by: Prasanna Kumar T S M <redacted> --- drivers/firmware/xilinx/zynqmp.c | 14 +++++++++++++- include/linux/firmware/xlnx-zynqmp.h | 4 ++++ 2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index b5e372190b44..0deb278b2c2d 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c@@ -2070,7 +2070,7 @@ ATTRIBUTE_GROUPS(zynqmp_firmware); * zynqmp_clear_pm_state() - Clear subsystem state. * @dev: Device pointer used for logging. * - * Clears PM specific data in TF-A. + * Clears PM specific data in TF-A and firmware. * * Return: Returns status, either success or error */
@@ -2095,6 +2095,18 @@ static int zynqmp_clear_pm_state(struct device *dev) "Failed to clear TF-A specific subsystem state: %d\n", ret); } else { dev_warn(dev, "TF_A_CLEAR_PM_STATE is not supported in TF-A: %d\n", ret); + } + + /* Check if the firmware supports the PM_DEV_ALL_PERIPH node ID */ + ret = do_feature_check_call(PM_RELEASE_NODE); + if ((ret & FIRMWARE_VERSION_MASK) >= PM_API_VERSION_3) { + /* Attempt to release all peripheral devices via firmware */ + ret = zynqmp_pm_release_node(PM_DEV_ALL_PERIPH); + if (ret) + dev_err(dev, "Failed to release all peripheral devices: %d\n", ret); + } else { + dev_warn(dev, + "Bulk device release is not supported by firmware: %d\n", ret); ret = 0; } }
diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h
index baaa88b0b197..ac39e5492961 100644
--- a/include/linux/firmware/xlnx-zynqmp.h
+++ b/include/linux/firmware/xlnx-zynqmp.h@@ -50,6 +50,7 @@ /* PM API versions */ #define PM_API_VERSION_1 1 #define PM_API_VERSION_2 2 +#define PM_API_VERSION_3 3 #define PM_PINCTRL_PARAM_SET_VERSION 2
@@ -145,6 +146,9 @@ #define XPM_EVENT_ERROR_MASK_NOC_NCR BIT(13) #define XPM_EVENT_ERROR_MASK_NOC_CR BIT(12) +/* Node ID for all peripheral devices */ +#define PM_DEV_ALL_PERIPH 0x18224FFFU + enum pm_module_id { PM_MODULE_ID = 0x0, XPM_MODULE_ID = 0x2,
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2.34.1