[PATCH v4 01/19] dt-bindings: firmware: qcom,scm: Add minidump SRAM property

[Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>]

On Qualcomm SoCs that support minidump, a word in always-on SRAM
is shared between the Operating System(HLOS) and boot firmware.
OS is expected to select the minidump download destination
either USB upload to a host PC or save to on-device storage.
Boot firmware will reads this word before DDR is initialized
on the warm reset following a crash to decide where to deliver
the minidump.

Add a 'sram' property to the SCM binding to allow the OS to
identify this SRAM region via a phandle.

Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/firmware/qcom,scm.yaml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
index 25f62bacbc91..2d68b4065341 100644
--- a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
+++ b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
@@ -129,6 +129,13 @@ properties:
           - description: offset of the download mode control register
     description: TCSR hardware block
 
+  sram:
+    description:
+      Phandle to a region in always-on SRAM used to store the download
+      mode value for boot firmware to read before DDR is initialised on
+      the next warm reset.
+    maxItems: 1
+
 allOf:
   # Clocks
   - if:
-- 
2.53.0