[PATCH v2 1/2] dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs

[Inochi Amaoto]

The timer registers of aclint don't follow the clint layout and can
be mapped on any different offset. As sg2042 uses separated timer
and mswi for its clint, it should follow the aclint spec and have
separated registers.

The previous patch introduces a new type of T-HEAD aclint timer which
has clint timer layout. Although the timer has the clint layout, it
should follow the aclint spec and uses the separated mtime and mtimecmp
regs. So a ABI change is needed to make the timer fit the aclint spec.

To make T-HEAD aclint timer more closer to the aclint spec, use two regs
to represent the mtime and mtimecmp.

Signed-off-by: Inochi Amaoto <inochiama@xxxxxxxxxxx>
Fixes: 4734449f7311 ("dt-bindings: timer: Add Sophgo sg2042 CLINT timer")
Link: https://lists.infradead.org/pipermail/opensbi/2023-October/005693.html
Link: https://github.com/riscv/riscv-aclint/blob/main/riscv-aclint.adoc
---
 .../devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml  | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml b/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml
index fbd235650e52..c3080962d902 100644
--- a/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml
+++ b/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml
@@ -17,7 +17,7 @@ properties:
       - const: thead,c900-aclint-mtimer

   reg:
-    maxItems: 1
+    maxItems: 2

   interrupts-extended:
     minItems: 1
@@ -38,6 +38,7 @@ examples:
                             <&cpu2intc 7>,
                             <&cpu3intc 7>,
                             <&cpu4intc 7>;
-      reg = <0xac000000 0x00010000>;
+      reg = <0xac000000 0x00000000>,
+            <0xac000000 0x0000c000>;
     };
 ...
--
2.42.1