[RFC PATCH v6 3/9] dt-bindings: iommu: rockchip: allow the RK3576 NPU MMU clock set

[Jiaxing Hu <gahing@gahingwoo.com>]

The RK3576 NPU MMUs need more than aclk and iface. With only those two
enabled the MMU accepts reads but silently drops register writes: a
DTE_ADDR value written from the power domain, while the domain clocks
are still on, reads back correctly, and the write rk_iommu_resume() does
microseconds later does not land at all. The vendor DT names the CBUF
clocks as that MMU's interface clocks and its driver keeps every NPU
clock on for as long as the device is powered.

The driver side of this is already upstream, commit 841363ebb508
("iommu/rockchip: Take all DT clocks"), which switched rk_iommu to
devm_clk_bulk_get_all(). Widen the schema to match so those nodes can
be described. minItems stays at 2, so every existing devicetree, which
all carry exactly aclk and iface, is unaffected.

Signed-off-by: Jiaxing Hu <gahing@gahingwoo.com>
---
 .../devicetree/bindings/iommu/rockchip,iommu.yaml         | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/iommu/rockchip,iommu.yaml b/Documentation/devicetree/bindings/iommu/rockchip,iommu.yaml
index 6ce41d11f..a3cedcaaa 100644
--- a/Documentation/devicetree/bindings/iommu/rockchip,iommu.yaml
+++ b/Documentation/devicetree/bindings/iommu/rockchip,iommu.yaml
@@ -42,14 +42,22 @@ properties:
     minItems: 1
 
   clocks:
+    minItems: 2
     items:
       - description: Core clock
       - description: Interface clock
+      - description: Compute clock, RK3576 NPU MMUs only
+      - description: Convolution buffer core clock, RK3576 NPU MMUs only
+      - description: Convolution buffer interface clock, RK3576 NPU MMUs only
 
   clock-names:
+    minItems: 2
     items:
       - const: aclk
       - const: iface
+      - const: npu
+      - const: aclk_cbuf
+      - const: hclk_cbuf
 
   "#iommu-cells":
     const: 0
-- 
2.43.0