Add Quad SPI driver for StarFive JH7110 SoC

Merge series from William Qiu <william.qiu@starfivetech.com>:

This patchset adds initial rudimentary support for the StarFive
Quad SPI controller driver. And this driver will be used in
StarFive's VisionFive 2 board.The first patch constrain
minItems/maxItems of resets for JH7110 QSPI and Patch 2 adds
support for StarFive JH7110 QSPI.

Documentation/devicetree/bindings/spi/cdns,qspi-nor.yaml

@@ -19,6 +19,33 @@ allOf:
     then:
       required:
         - power-domains
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: starfive,jh7110-qspi
+    then:
+      properties:
+        resets:
+          minItems: 2
+          maxItems: 3
+
+        reset-names:
+          minItems: 2
+          maxItems: 3
+          items:
+            enum: [ qspi, qspi-ocp, rstc_ref ]
+
+    else:
+      properties:
+        resets:
+          maxItems: 2
+
+        reset-names:
+          minItems: 1
+          maxItems: 2
+          items:
+            enum: [ qspi, qspi-ocp ]
 
 properties:
   compatible:
@@ -30,6 +57,7 @@ properties:
               - intel,lgm-qspi
               - xlnx,versal-ospi-1.0
               - intel,socfpga-qspi
+              - starfive,jh7110-qspi
           - const: cdns,qspi-nor
       - const: cdns,qspi-nor
 
@@ -79,13 +107,14 @@ properties:
     maxItems: 1
 
   resets:
-    maxItems: 2
+    minItems: 2
+    maxItems: 3
 
   reset-names:
-    minItems: 1
-    maxItems: 2
+    minItems: 2
+    maxItems: 3
     items:
-      enum: [ qspi, qspi-ocp ]
+      enum: [ qspi, qspi-ocp, rstc_ref ]
 
 required:
   - compatible

drivers/spi/Kconfig

@@ -239,7 +239,7 @@ config SPI_CADENCE
 
 config SPI_CADENCE_QUADSPI
 	tristate "Cadence Quad SPI controller"
-	depends on OF && (ARM || ARM64 || X86 || COMPILE_TEST)
+	depends on OF && (ARM || ARM64 || X86 || RISCV || COMPILE_TEST)
 	help
 	  Enable support for the Cadence Quad SPI Flash controller.
 

drivers/spi/spi-cadence-quadspi.c

@@ -1615,7 +1615,7 @@ static int cqspi_setup_flash(struct cqspi_st *cqspi)
 static int cqspi_probe(struct platform_device *pdev)
 {
 	const struct cqspi_driver_platdata *ddata;
-	struct reset_control *rstc, *rstc_ocp;
+	struct reset_control *rstc, *rstc_ocp, *rstc_ref;
 	struct device *dev = &pdev->dev;
 	struct spi_master *master;
 	struct resource *res_ahb;
@@ -1705,6 +1705,17 @@ static int cqspi_probe(struct platform_device *pdev)
 		goto probe_reset_failed;
 	}
 
+	if (of_device_is_compatible(pdev->dev.of_node, "starfive,jh7110-qspi")) {
+		rstc_ref = devm_reset_control_get_optional_exclusive(dev, "rstc_ref");
+		if (IS_ERR(rstc_ref)) {
+			ret = PTR_ERR(rstc_ref);
+			dev_err(dev, "Cannot get QSPI REF reset.\n");
+			goto probe_reset_failed;
+		}
+		reset_control_assert(rstc_ref);
+		reset_control_deassert(rstc_ref);
+	}
+
 	reset_control_assert(rstc);
 	reset_control_deassert(rstc);
 
@@ -1859,6 +1870,10 @@ static const struct cqspi_driver_platdata versal_ospi = {
 	.get_dma_status = cqspi_get_versal_dma_status,
 };
 
+static const struct cqspi_driver_platdata jh7110_qspi = {
+	.quirks = CQSPI_DISABLE_DAC_MODE,
+};
+
 static const struct of_device_id cqspi_dt_ids[] = {
 	{
 		.compatible = "cdns,qspi-nor",
@@ -1884,6 +1899,10 @@ static const struct of_device_id cqspi_dt_ids[] = {
 		.compatible = "intel,socfpga-qspi",
 		.data = &socfpga_qspi,
 	},
+	{
+		.compatible = "starfive,jh7110-qspi",
+		.data = &jh7110_qspi,
+	},
 	{ /* end of table */ }
 };