[PATCH 06/10] dt-bindings: arm: sunxi: Expand MBUS binding

Samuel Holland samuel at sholland.org
Tue Sep 28 21:42:50 PDT 2021


The MBUS provides more than address translation and bandwidth control.
It also provides a PMU to measure bandwidth usage by certain masters,
and it provides notification via IRQ when they are active or idle.

The MBUS is also tightly integrated with the DRAM controller to provide
a Memory Dynamic Frequency Scaling (MDFS) feature. In view of this, the
MBUS binding needs to represent the hardware resources needed for MDFS,
which include the clocks and MMIO range of the adjacent DRAM controller.

Add the additional resources for the H3 and A64 compatibles, and a new
example showing how they are used.

Signed-off-by: Samuel Holland <samuel at sholland.org>
---
 .../arm/sunxi/allwinner,sun4i-a10-mbus.yaml   | 75 ++++++++++++++++++-
 1 file changed, 72 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/sunxi/allwinner,sun4i-a10-mbus.yaml b/Documentation/devicetree/bindings/arm/sunxi/allwinner,sun4i-a10-mbus.yaml
index e713a6fe4cf7..c1fb404d2fb3 100644
--- a/Documentation/devicetree/bindings/arm/sunxi/allwinner,sun4i-a10-mbus.yaml
+++ b/Documentation/devicetree/bindings/arm/sunxi/allwinner,sun4i-a10-mbus.yaml
@@ -33,10 +33,33 @@ properties:
       - allwinner,sun50i-a64-mbus
 
   reg:
-    maxItems: 1
+    minItems: 1
+    items:
+      - description: MBUS interconnect/bandwidth/PMU registers
+      - description: DRAM controller/PHY registers
+
+  reg-names:
+    items:
+      - const: "mbus"
+      - const: "dram"
 
   clocks:
+    minItems: 1
+    items:
+      - description: MBUS interconnect module clock
+      - description: DRAM controller/PHY module clock
+      - description: Register bus clock, shared by MBUS and DRAM
+
+  clock-names:
+    items:
+      - const: "mbus"
+      - const: "dram"
+      - const: "bus"
+
+  interrupts:
     maxItems: 1
+    description:
+      MBUS PMU activity interrupt.
 
   dma-ranges:
     description:
@@ -53,13 +76,42 @@ required:
   - clocks
   - dma-ranges
 
+if:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - allwinner,sun8i-h3-mbus
+          - allwinner,sun50i-a64-mbus
+
+then:
+  properties:
+    reg:
+      minItems: 2
+
+    clocks:
+      minItems: 3
+
+  required:
+    - reg-names
+    - clock-names
+
+else:
+  properties:
+    reg:
+      maxItems: 1
+
+    clocks:
+      maxItems: 1
+
 additionalProperties: false
 
 examples:
   - |
-    #include <dt-bindings/clock/sun5i-ccu.h>
+    #include <dt-bindings/clock/sun50i-a64-ccu.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
 
-    mbus: dram-controller at 1c01000 {
+    dram-controller at 1c01000 {
         compatible = "allwinner,sun5i-a13-mbus";
         reg = <0x01c01000 0x1000>;
         clocks = <&ccu CLK_MBUS>;
@@ -69,4 +121,21 @@ examples:
         #interconnect-cells = <1>;
     };
 
+  - |
+    dram-controller at 1c62000 {
+        compatible = "allwinner,sun50i-a64-mbus";
+        reg = <0x01c62000 0x1000>,
+              <0x01c63000 0x1000>;
+        reg-names = "mbus", "dram";
+        clocks = <&ccu CLK_MBUS>,
+                 <&ccu CLK_DRAM>,
+                 <&ccu CLK_BUS_DRAM>;
+        clock-names = "mbus", "dram", "bus";
+        interrupts = <GIC_SPI 69 IRQ_TYPE_LEVEL_HIGH>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+        dma-ranges = <0x00000000 0x40000000 0xc0000000>;
+        #interconnect-cells = <1>;
+    };
+
 ...
-- 
2.31.1




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