From b91cf01cf3e63a627b3b65f4284dcf9a4deb80f9 Mon Sep 17 00:00:00 2001 From: Inochi Amaoto Date: Mon, 4 Dec 2023 17:51:08 +0800 Subject: dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs 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 introduced a new type of T-HEAD aclint timer which has clint timer layout. Although it has the clint timer 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 regs-names to represent the mtimecmp register, which can avoid hack for unsupport mtime register of T-HEAD aclint timer. Also, as T-HEAD aclint only supports mtimecmp, it is unnecessary to implement the whole aclint spec. To make this binding T-HEAD specific, only add reg-name for existed register. For details, see the discussion in the last link. Signed-off-by: Inochi Amaoto 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 Link: https://lore.kernel.org/all/IA1PR20MB4953F9D77FFC76A9D236922DBBB6A@IA1PR20MB4953.namprd20.prod.outlook.com/ Acked-by: Guo Ren Acked-by: Conor Dooley Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/IA1PR20MB49531ED1BCC00D6B265C2D10BB86A@IA1PR20MB4953.namprd20.prod.outlook.com --- .../devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml b/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml index fbd235650e52..2e92bcdeb423 100644 --- a/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml +++ b/Documentation/devicetree/bindings/timer/thead,c900-aclint-mtimer.yaml @@ -17,7 +17,12 @@ properties: - const: thead,c900-aclint-mtimer reg: - maxItems: 1 + items: + - description: MTIMECMP Registers + + reg-names: + items: + - const: mtimecmp interrupts-extended: minItems: 1 @@ -28,6 +33,7 @@ additionalProperties: false required: - compatible - reg + - reg-names - interrupts-extended examples: @@ -39,5 +45,6 @@ examples: <&cpu3intc 7>, <&cpu4intc 7>; reg = <0xac000000 0x00010000>; + reg-names = "mtimecmp"; }; ... -- cgit v1.2.3