[PATCH v2 2/6] dt-bindings: riscv: Add Zawrs ISA extension description

Andrew Jones
2024-04-19T13:53:27Z

Add description for the Zawrs (Wait-on-Reservation-Set) ISA extension
which was ratified in commit 98918c844281 of riscv-isa-manual.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
---
.../devicetree/bindings/riscv/extensions.yaml | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
index 468c646247aa..584da2f539e5 100644
--- a/Documentation/devicetree/bindings/riscv/extensions.yaml
+++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
@@ -177,6 +177,18 @@ properties:
is supported as ratified at commit 5059e0ca641c ("update to
ratified") of the riscv-zacas.

+ - const: zawrs
+ description: |
+ The Zawrs extension for entering a low-power state or for trapping
+ to a hypervisor while waiting on a store to a memory location, as
+ ratified in commit 98918c844281 ("Merge pull request #1217 from
+ riscv/zawrs") of riscv-isa-manual. Linux assumes that WRS.NTO will
+ either always eventually terminate the stall due to the reservation
+ set becoming invalid, implementation-specific other reasons, or
+ because a higher privilege level has configured it to cause an
+ illegal instruction exception after an implementation-specific
+ bounded time limit.
+
- const: zba
description: |
The standard Zba bit-manipulation extension for address generation
--
2.44.0