[PATCH] firmware: xilinx: Request pre-allocated peripheral nodes after bulk release
From: Jay Buddhabhatti <hidden>
Date: 2026-09-23 10:04:34
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Subsystem:
the rest · Maintainer:
Linus Torvalds
During a kexec restart, zynqmp_clear_pm_state() releases all peripheral devices via PM_DEV_ALL_PERIPH. Pre-allocated nodes are then left released, so Linux no longer owns them and later peripheral access can fail. Immediately re-request those nodes with zynqmp_pm_request_node( PM_DEV_ALL_PERIPH, ...) so Linux retains ownership. On a graceful kexec this runs from zynqmp_firmware_shutdown(). On a crash kernel restart it runs from zynqmp_firmware_probe() in the reloaded kernel. The bulk request depends on firmware support for PM_DEV_ALL_PERIPH (PM_REQUEST_NODE feature check version >= PM_API_VERSION_3). On firmware that does not implement it, the request is skipped and a warning is logged. Errors are already logged inside zynqmp_clear_pm_state() and zynqmp_firmware_probe() does not abort if the request fails. Also, drop the redundant ret = 0 assignments whose value is overwritten by the next do_feature_check_call() Signed-off-by: Jay Buddhabhatti <redacted> --- drivers/firmware/xilinx/zynqmp.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index fe650747ac91..96dbb23eb673 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c@@ -2193,7 +2193,6 @@ static int zynqmp_clear_pm_state(struct device *dev) "Failed to clear EL3 PM subsystem state: %d\n", ret); } else { dev_warn(dev, "TF_A_CLEAR_PM_STATE is not supported by EL3 firmware: %d\n", ret); - ret = 0; } /* Check if the firmware supports the PM_DEV_ALL_PERIPH node ID */
@@ -2206,7 +2205,19 @@ static int zynqmp_clear_pm_state(struct device *dev) } else { dev_warn(dev, "Bulk device release is not supported by firmware: %d\n", ret); - ret = 0; + } + + /* Check if the firmware supports the PM_DEV_ALL_PERIPH node ID */ + ret = do_feature_check_call(PM_REQUEST_NODE); + if (ret >= 0 && ((ret & FIRMWARE_VERSION_MASK) >= PM_API_VERSION_3)) { + /* Attempt to request all nodes via firmware */ + ret = zynqmp_pm_request_node(PM_DEV_ALL_PERIPH, 0, 0, 0); + if (ret) + dev_err(dev, "Failed to request all peripheral devices: %d\n", ret); + } else { + dev_warn(dev, + "Firmware doesn't support request all peripheral devices at once: %d\n", + ret); } /* Check if the firmware supports the PM_ALL_NOTIFIERS node ID */
--
2.54.0