On 26/02/2026 07:03, Himanshu Chauhan wrote:

On Fri, Feb 20, 2026 at 7:15 PM Ahmed Tiba [off-list ref] wrote:

quoted

Describe the DeviceTree node that exposes the Arm firmware-first handler
CPER provider and hook the file into MAINTAINERS so the binding has an
owner.

Signed-off-by: Ahmed Tiba <redacted>
---
  .../devicetree/bindings/firmware/arm,ras-ffh.yaml  | 71 ++++++++++++++++++++++
  MAINTAINERS                                        |  5 ++
  2 files changed, 76 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/arm,ras-ffh.yaml b/Documentation/devicetree/bindings/firmware/arm,ras-ffh.yaml
new file mode 100644
index 000000000000..eccbaaf45885
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/arm,ras-ffh.yaml

@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/arm,ras-ffh.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Arm Firmware-First Handler (FFH) CPER provider

Please don't called it FFH. FFH stands for Fixed Feature Hardware and
ACPI uses it at multiple places. It is causing confusion.

Agreed. I can drop "ffh" and rename it to "arm,ras-cper".

quoted

+
+maintainers:
+  - Ahmed Tiba [off-list ref]
+
+description: |
+  Arm Reliability, Availability and Serviceability (RAS) firmware can expose
+  a firmware-first handler (FFH) that provides UEFI CPER Generic Error Status
+  blocks directly via DeviceTree. The firmware owns the CPER buffer
+  and notifies the OS through an interrupt.
+
+properties:
+  compatible:
+    const: arm,ras-ffh
+
+  reg:
+    minItems: 1
+    items:
+      - description:
+          CPER Generic Error Status block exposed by firmware
+      - description:
+          Optional 32- or 64-bit doorbell register used on platforms
+          where firmware needs an explicit "ack" handshake before overwriting
+          the CPER buffer. Firmware watches bit 0 and expects the OS to set it
+          once the current status block has been consumed.
+
+  interrupts:
+    maxItems: 1
+    description:
+      Interrupt used to signal that a new status record is ready.
+
+  memory-region:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Optional phandle to the reserved-memory entry that backs the status
+      buffer so firmware and the OS use the same carved-out region.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    reserved-memory {
+      #address-cells = <2>;
+      #size-cells = <2>;
+      ras_cper_buffer: cper@fe800000 {
+        reg = <0x0 0xfe800000 0x0 0x1000>;
+        no-map;
+      };
+    };
+
+    error-handler@fe800000 {
+      compatible = "arm,ras-ffh";
+      reg = <0xfe800000 0x1000>,
+            <0xfe810000 0x4>;
+      memory-region = <&ras_cper_buffer>;
+      interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
+    };
+...

diff --git a/MAINTAINERS b/MAINTAINERS
index b8d8a5c41597..47db7877b485 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS

@@ -22027,6 +22027,11 @@ M:     Alexandre Bounine <alex.bou9@gmail.com>
  S:     Maintained
  F:     drivers/rapidio/

+RAS ERROR STATUS
+M:     Ahmed Tiba <ahmed.tiba@arm.com>
+S:     Maintained
+F:     Documentation/devicetree/bindings/firmware/arm,ras-ffh.yaml
+
  RAS INFRASTRUCTURE
  M:     Tony Luck <tony.luck@intel.com>
  M:     Borislav Petkov <bp@alien8.de>

--

2.43.0