[PATCH v1 3/9] arm64: dts: agilex5: add Cadence SD6HC controller and SOCDK enablement

[Tanmay Kathpalia <tanmay.kathpalia@altera.com>]

The Agilex5 SoC device tree gains an SD/MMC controller node backed by
the Cadence SD6HC, with IOMMU integration via the system SMMU. Card
power is supplied by a fixed 3.3V regulator and I/O voltage switching
between 1.8V and 3.3V is handled by a GPIO-controlled regulator.

The SOCDK board enables the controller for SD-only operation in 4-bit
bus width with high-speed and SDR104 UHS-I modes at 200 MHz maximum
clock. SDHCI capability overrides clear the SDR50 tuning flag and
override the clock base mask to report 200 MHz.

Signed-off-by: Tanmay Kathpalia <tanmay.kathpalia@altera.com>
---
 .../arm64/boot/dts/intel/socfpga_agilex5.dtsi | 38 +++++++++++++++++++
 .../boot/dts/intel/socfpga_agilex5_socdk.dts  | 26 +++++++++++++
 2 files changed, 64 insertions(+)

diff --git a/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi b/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi
index 352c96d144a8..7e080f13166f 100644
--- a/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi
+++ b/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi
@@ -300,6 +300,44 @@ portb: gpio-controller@0 {
 			};
 		};
 
+		sd_emmc_power: regulator-fixed-3p3v {
+			compatible = "regulator-fixed";
+			regulator-name = "card-power";
+			regulator-min-microvolt = <3300000>;
+			regulator-max-microvolt = <3300000>;
+			regulator-always-on;
+		};
+
+		sd_io_1v8_reg: regulator-1p8v {
+			compatible = "regulator-gpio";
+			regulator-name = "sd-bus-io-power";
+			regulator-min-microvolt = <1800000>;
+			regulator-max-microvolt = <3300000>;
+			states =	<1800000 0x1>,
+					<3300000 0x0>;
+		};
+
+		emmc: mmc@10808000 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			compatible = "altr,agilex5-sd6hc", "cdns,sd6hc";
+			reg = <0x10808000 0x1000>;
+			interrupts = <GIC_SPI 96 IRQ_TYPE_LEVEL_HIGH>;
+			fifo-depth = <0x800>;
+			resets = <&rst SDMMC_RESET>, <&rst COMBOPHY_RESET>, <&rst SDMMC_OCP_RESET>;
+			reset-names = "sdhc-reset", "combophy", "sdmmc-ocp";
+			/*
+			 * "ciu" (SDMCLK) is listed first so it is selected as the
+			 * primary clock by the SDHCI platform layer; the SD6HC PHY
+			 * timing calculations are derived from this clock rate.
+			 */
+			clocks = <&clkmgr AGILEX5_SDMCLK>, <&clkmgr AGILEX5_L4_MP_CLK>;
+			clock-names = "ciu", "biu";
+			iommus = <&smmu 5>;
+			dma-coherent;
+			status = "disabled";
+		};
+
 		nand: nand-controller@10b80000 {
 			compatible = "cdns,hp-nfc";
 			reg = <0x10b80000 0x10000>,
diff --git a/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk.dts b/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk.dts
index 262bb3e8e5c7..a9de824e292a 100644
--- a/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk.dts
+++ b/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk.dts
@@ -98,6 +98,32 @@ root: partition@4200000 {
 	};
 };
 
+&sd_io_1v8_reg {
+	gpios = <&portb 3 GPIO_ACTIVE_HIGH>;
+};
+
+&emmc {
+	status = "okay";
+
+	no-mmc;
+	disable-wp;
+	bus-width = <4>;
+	cap-sd-highspeed;
+	sd-uhs-sdr104;
+	vmmc-supply = <&sd_emmc_power>;
+	vqmmc-supply = <&sd_io_1v8_reg>;
+	max-frequency = <200000000>;
+	/*
+	 * SDHCI capability overrides:
+	 *  - caps_mask[0] 0x0000ff00 / caps[0] 0x0000c800:
+	 *      Override SDHCI_CLOCK_BASE_MASK to 0xc8 (200 MHz).
+	 *  - caps_mask[1] 0x00002000 / caps[1] 0:
+	 *      Clear SDHCI_USE_SDR50_TUNING; SDR50 tuning is unsupported.
+	 */
+	sdhci-caps = <0x00000000 0x0000c800>;
+	sdhci-caps-mask = <0x00002000 0x0000ff00>;
+};
+
 &uart0 {
 	status = "okay";
 };
-- 
2.43.7