Add support for Microchip CoreSPI Controller

Merge series from Prajna Rajendra Kumar <prajna.rajendrakumar@microchip.com>:

This patch series adds support for the Microchip FPGA CoreSPI "soft" IP
and documents its device tree bindings.

As preparation, the existing Microchip SPI driver is renamed to clearly
indicate that it supports only the Microchip PolarFire SoC "hard" controller.
Although it was originally named with the expectation that it might also
cover the FPGA CoreSPI "soft" IP, the register layouts differ significantly,
so separate drivers are required.

1 files changed, 68 insertions, 2 deletions

diff --git a/Documentation/devicetree/bindings/spi/microchip,mpfs-spi.yaml b/Documentation/devicetree/bindings/spi/microchip,mpfs-spi.yaml
index 62a568bdbfa0..636338d24bdf 100644
--- a/Documentation/devicetree/bindings/spi/microchip,mpfs-spi.yaml
+++ b/Documentation/devicetree/bindings/spi/microchip,mpfs-spi.yaml
@@ -21,11 +21,13 @@ properties:
               - microchip,mpfs-qspi
               - microchip,pic64gx-qspi
           - const: microchip,coreqspi-rtl-v2
-      - const: microchip,coreqspi-rtl-v2 # FPGA QSPI
+      - enum:
+          - microchip,coreqspi-rtl-v2 # FPGA QSPI
+          - microchip,corespi-rtl-v5 # FPGA CoreSPI
+          - microchip,mpfs-spi
       - items:
           - const: microchip,pic64gx-spi
           - const: microchip,mpfs-spi
-      - const: microchip,mpfs-spi
 
   reg:
     maxItems: 1
@@ -39,6 +41,45 @@ properties:
   clocks:
     maxItems: 1
 
+  microchip,apb-datawidth:
+    description: APB bus data width in bits.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [8, 16, 32]
+    default: 8
+
+  microchip,frame-size:
+    description: |
+      Number of bits per SPI frame, as configured in Libero.
+      In Motorola and TI modes, this corresponds directly
+      to the requested frame size. For NSC mode this is set
+      to 9 + the required data frame size.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 4
+    maximum: 32
+    default: 8
+
+  microchip,protocol-configuration:
+    description: CoreSPI protocol selection. Determines operating mode
+    $ref: /schemas/types.yaml#/definitions/string
+    enum:
+      - motorola
+      - ti
+      - nsc
+    default: motorola
+
+  microchip,motorola-mode:
+    description: Motorola SPI mode selection
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [0, 1, 2, 3]
+    default: 3
+
+  microchip,ssel-active:
+    description: |
+      Keep SSEL asserted between frames when using the Motorola protocol.
+      When present, the controller keeps SSEL active across contiguous
+      transfers and deasserts only when the overall transfer completes.
+    type: boolean
+
 required:
   - compatible
   - reg
@@ -71,6 +112,31 @@ allOf:
         num-cs:
           maximum: 1
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: microchip,corespi-rtl-v5
+    then:
+      properties:
+        num-cs:
+          minimum: 1
+          maximum: 8
+          default: 8
+
+        fifo-depth:
+          minimum: 1
+          maximum: 32
+          default: 4
+
+    else:
+      properties:
+        microchip,apb-datawidth: false
+        microchip,frame-size: false
+        microchip,protocol-configuration: false
+        microchip,motorola-mode: false
+        microchip,ssel-active: false
+
 unevaluatedProperties: false
 
 examples: