diff options
| author | Jay Buddhabhatti <jay.buddhabhatti@amd.com> | 2026-07-29 05:25:22 -0700 |
|---|---|---|
| committer | Michal Simek <michal.simek@amd.com> | 2026-08-10 09:30:44 +0200 |
| commit | 0e8860367da261116cd290bcd6a54d2e597a0c5c (patch) | |
| tree | f3ecf5e54a9877d433b7b0e7eaa6dbe8ed10ff4a | |
| parent | 84dbfa5519cf6583d09ee0123ac580542b144553 (diff) | |
firmware: xilinx: Clear firmware notifiers across kexec transitions
During a kexec restart, only the kernel is reloaded but notifier callbacks
in firmware persist, causing state mismatches between kernel and firmware.
To address this, introduce PM_ALL_NOTIFIERS node ID to unregister all
notifier callbacks during kexec. On a graceful kexec restart, this occurs
in zynqmp_firmware_shutdown(). On a crash kernel restart, it happens in
zynqmp_firmware_probe() in the reloaded kernel.
Unregistering all notifiers depends on firmware support for the
PM_ALL_NOTIFIERS node ID. On firmware that does not implement it (the
feature check reports a version below PM_API_VERSION_3) the step is
skipped and a warning such as "Firmware doesn't support unregister all
notifiers at once" is logged, e.g. on Versal NET firmware that predates
this API.
Signed-off-by: Jay Buddhabhatti <jay.buddhabhatti@amd.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Reviewed-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
Link: https://patch.msgid.link/20260729122522.3732875-4-jay.buddhabhatti@amd.com
Signed-off-by: Michal Simek <michal.simek@amd.com>
| -rw-r--r-- | drivers/firmware/xilinx/zynqmp.c | 14 | ||||
| -rw-r--r-- | include/linux/firmware/xlnx-zynqmp.h | 3 |
2 files changed, 17 insertions, 0 deletions
diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c index 4bf6c9eabebc..f44785aee808 100644 --- a/drivers/firmware/xilinx/zynqmp.c +++ b/drivers/firmware/xilinx/zynqmp.c @@ -2115,6 +2115,20 @@ static int zynqmp_clear_pm_state(struct device *dev) "Bulk device release is not supported by firmware: %d\n", ret); ret = 0; } + + /* Check if the firmware supports the PM_ALL_NOTIFIERS node ID */ + ret = do_feature_check_call(PM_REGISTER_NOTIFIER); + if (ret >= 0 && ((ret & FIRMWARE_VERSION_MASK) >= PM_API_VERSION_3)) { + /* Attempt to unregister all notifier callbacks via firmware */ + ret = zynqmp_pm_register_notifier(PM_ALL_NOTIFIERS, 0, 0, 0); + if (ret) + dev_err(dev, "Failed to unregister all notifiers: %d\n", ret); + } else { + dev_warn(dev, + "Firmware doesn't support unregister all notifiers at once: %d\n", + ret); + ret = 0; + } } return ret; diff --git a/include/linux/firmware/xlnx-zynqmp.h b/include/linux/firmware/xlnx-zynqmp.h index ac39e5492961..69a2f74269f3 100644 --- a/include/linux/firmware/xlnx-zynqmp.h +++ b/include/linux/firmware/xlnx-zynqmp.h @@ -149,6 +149,9 @@ /* Node ID for all peripheral devices */ #define PM_DEV_ALL_PERIPH 0x18224FFFU +/* Node ID for all notifier callbacks */ +#define PM_ALL_NOTIFIERS 0xFFFFFFFFU + enum pm_module_id { PM_MODULE_ID = 0x0, XPM_MODULE_ID = 0x2, |