ARM: dts: ux500: Add device tree for Samsung Galaxy S III mini (GT-I8190)

The Samsung Galaxy S III mini (GT-I8190) is a smartphone with Ux500 SoC
released in 2012. Thanks to the great mainline support for Ux500,
it can actually run mainline Linux quite well.

Add a new device tree for it with support for:
  - Internal Storage (eMMC)
  - External Storage (Micro SD card)
  - UART
  - GPIO Buttons
  - Vibrator

Note that the device tree cannot be booted directly with
the original (Samsung) bootloader. It keeps the L2 cache turned on,
which causes the kernel to hang shortly after decompression.

As a workaround I have created a port of (mainline) U-Boot,
which locks the L2 cache before booting Linux. At the moment it does not
replace the Samsung bootloader, instead we let the original bootloader
load U-Boot as an another (intermediate) bootloader.

Another advantage of this is that U-Boot has proper device tree support,
so we do not need to hardcode the kernel command line in the device tree.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20191219202052.19039-5-stephan@gerhold.netSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/Makefile

@@ -1183,7 +1183,8 @@ dtb-$(CONFIG_ARCH_U8500) += \
 	ste-hrefprev60-tvk.dtb \
 	ste-hrefv60plus-stuib.dtb \
 	ste-hrefv60plus-tvk.dtb \
-	ste-href520-tvk.dtb
+	ste-href520-tvk.dtb \
+	ste-ux500-samsung-golden.dtb
 dtb-$(CONFIG_ARCH_UNIPHIER) += \
 	uniphier-ld4-ref.dtb \
 	uniphier-ld6b-ref.dtb \

arch/arm/boot/dts/ste-ux500-samsung-golden.dts

+// SPDX-License-Identifier: GPL-2.0-only
+/dts-v1/;
+
+#include "ste-db8500.dtsi"
+#include "ste-ab8505.dtsi"
+#include "ste-dbx5x0-pinctrl.dtsi"
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/*
+ * Note: This device tree cannot be booted directly with the Samsung bootloader.
+ * You need an intermediate, device-tree compatible bootloader
+ * that locks the L2 cache. Otherwise the kernel will crash after decompression.
+ *
+ * There is a port of (mainline) U-Boot, see
+ * https://wiki.postmarketos.org/wiki/ST-Ericsson_NovaThor_U8500#U-Boot
+ */
+/ {
+	model = "Samsung Galaxy S III mini (GT-I8190)";
+	compatible = "samsung,golden", "st-ericsson,u8500";
+
+	chosen {
+		stdout-path = &serial2;
+	};
+
+	soc {
+		/* External Micro SD card slot */
+		sdi0_per1@80126000 {
+			status = "okay";
+
+			arm,primecell-periphid = <0x10480180>;
+			max-frequency = <100000000>;
+			bus-width = <4>;
+
+			non-removable;
+			/*
+			 * Unfortunately, there is no way to enable the UHS
+			 * modes due to a limitation of the SD level translator:
+			 * It will either translate to 2.9V or disconnect the
+			 * DATA lines, so switching to 1.8V signal voltage fails.
+			 */
+			cap-sd-highspeed;
+			cap-mmc-highspeed;
+			st,sig-pin-fbclk;
+			full-pwr-cycle;
+
+			vmmc-supply = <&ab8500_ldo_aux3_reg>;
+			vqmmc-supply = <&sd_level_translator>;
+
+			pinctrl-names = "default", "sleep";
+			pinctrl-0 = <&mc0_a_2_default>;
+			pinctrl-1 = <&mc0_a_2_sleep>;
+		};
+
+		/* WLAN SDIO */
+		sdi1_per2@80118000 {
+			status = "okay";
+
+			arm,primecell-periphid = <0x10480180>;
+			max-frequency = <50000000>;
+			bus-width = <4>;
+
+			non-removable;
+			cap-sd-highspeed;
+
+			pinctrl-names = "default", "sleep";
+			pinctrl-0 = <&mc1_a_2_default>;
+			pinctrl-1 = <&mc1_a_2_sleep>;
+		};
+
+		/* eMMC */
+		sdi2_per3@80005000 {
+			status = "okay";
+
+			arm,primecell-periphid = <0x10480180>;
+			max-frequency = <100000000>;
+			bus-width = <8>;
+
+			non-removable;
+			cap-mmc-highspeed;
+			mmc-ddr-1_8v;
+
+			vmmc-supply = <&vmem_3v3>;
+
+			pinctrl-names = "default", "sleep";
+			pinctrl-0 = <&mc2_a_1_default>;
+			pinctrl-1 = <&mc2_a_1_sleep>;
+		};
+
+		/* BT UART */
+		uart@80120000 {
+			status = "okay";
+
+			pinctrl-names = "default", "sleep";
+			pinctrl-0 = <&u0_a_1_default>;
+			pinctrl-1 = <&u0_a_1_sleep>;
+		};
+
+		/* GPF UART */
+		uart@80121000 {
+			status = "okay";
+
+			pinctrl-names = "default", "sleep";
+			pinctrl-0 = <&u1rxtx_a_1_default &u1ctsrts_a_1_default>;
+			pinctrl-1 = <&u1rxtx_a_1_sleep &u1ctsrts_a_1_sleep>;
+		};
+
+		/* Debugging console UART */
+		uart@80007000 {
+			status = "okay";
+
+			pinctrl-names = "default", "sleep";
+			pinctrl-0 = <&u2rxtx_c_1_default>;
+			pinctrl-1 = <&u2rxtx_c_1_sleep>;
+		};
+
+		prcmu@80157000 {
+			ab8505 {
+				ab8500_usb {
+					pinctrl-names = "default", "sleep";
+					pinctrl-0 = <&usb_a_1_default>;
+					pinctrl-1 = <&usb_a_1_sleep>;
+				};
+
+				ab8505-regulators {
+					ab8500_ldo_aux1 {
+						regulator-name = "sensor_3v";
+						regulator-min-microvolt = <3000000>;
+						regulator-max-microvolt = <3000000>;
+					};
+
+					ab8500_ldo_aux2 {
+						regulator-name = "vreg_tsp_a3v3";
+						regulator-min-microvolt = <3300000>;
+						regulator-max-microvolt = <3300000>;
+					};
+
+					ab8500_ldo_aux3 {
+						regulator-name = "vdd_tf_2v91";
+					};
+
+					ab8500_ldo_aux4 {
+						regulator-name = "key_led_3.3v";
+						regulator-min-microvolt = <3300000>;
+						regulator-max-microvolt = <3300000>;
+					};
+
+					ab8500_ldo_aux5 {
+						regulator-name = "vreg_tsp_1v8";
+						regulator-min-microvolt = <1800000>;
+						regulator-max-microvolt = <1800000>;
+					};
+
+					ab8500_ldo_aux6 {
+						regulator-name = "touch_key_2.2v";
+						regulator-min-microvolt = <2200000>;
+						regulator-max-microvolt = <2200000>;
+					};
+
+					ab8500_ldo_aux8 {
+						regulator-name = "sensor_1v8";
+					};
+				};
+			};
+		};
+	};
+
+	gpio-keys {
+		compatible = "gpio-keys";
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&gpio_keys_default>;
+
+		label = "GPIO Buttons";
+
+		volume-up {
+			label = "Volume Up";
+			/* GPIO67 (VOL_UP) */
+			gpios = <&gpio2 3 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_VOLUMEUP>;
+		};
+
+		volume-down {
+			label = "Volume Down";
+			/* GPIO92 (VOL_DOWN) */
+			gpios = <&gpio2 28 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_VOLUMEDOWN>;
+		};
+
+		home {
+			label = "Home";
+			/* GPIO91 (HOME_KEY) */
+			gpios = <&gpio2 27 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_HOMEPAGE>;
+		};
+	};
+
+	vibrator {
+		compatible = "gpio-vibrator";
+		/* GPIO195 (MOT_EN) */
+		enable-gpios = <&gpio6 3 GPIO_ACTIVE_HIGH>;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&vibrator_default>;
+	};
+
+	/* External LDO for eMMC */
+	vmem_3v3: regulator-vmem {
+		compatible = "regulator-fixed";
+
+		regulator-name = "vmem_3v3";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		regulator-boot-on;
+
+		startup-delay-us = <200>;
+
+		/* GPIO223 (MEM_LDO_EN) */
+		gpio = <&gpio6 31 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&mem_ldo_default>;
+	};
+
+	/* TI TXS0206-29 level translator for 2.9 V */
+	sd_level_translator: regulator-sd-level-translator {
+		compatible = "regulator-fixed";
+
+		regulator-name = "sd-level-translator";
+		regulator-min-microvolt = <2900000>;
+		regulator-max-microvolt = <2900000>;
+
+		startup-delay-us = <200>;
+
+		/* GPIO87 (TXS0206-29_EN) */
+		gpios = <&gpio2 23 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&sd_level_translator_default>;
+	};
+};
+
+&pinctrl {
+	gpio-keys {
+		gpio_keys_default: gpio_keys_default {
+			golden_cfg1 {
+				pins = "GPIO67",	/* VOL_UP */
+				       "GPIO91",	/* HOME_KEY */
+				       "GPIO92";	/* VOL_DOWN */
+				ste,config = <&gpio_in_pu>;
+			};
+		};
+	};
+
+	sdi0 {
+		sd_level_translator_default: sd_level_translator_default {
+			golden_cfg1 {
+				pins = "GPIO87_B3";	/* TXS0206-29_EN */
+				ste,config = <&gpio_out_lo>;
+			};
+		};
+	};
+
+	sdi2 {
+		mem_ldo_default: mem_ldo_default {
+			golden_cfg1 {
+				pins = "GPIO223_AH9";	/* MEM_LDO_EN */
+				ste,config = <&gpio_out_hi>;
+			};
+		};
+	};
+
+	vibrator {
+		vibrator_default: vibrator_default {
+			golden_cfg1 {
+				pins = "GPIO195_AG28";	/* MOT_EN */
+				ste,config = <&gpio_out_lo>;
+			};
+		};
+	};
+};
+
+&ab8505_gpio {
+	/* Hog a few default settings */
+	pinctrl-names = "default";
+	pinctrl-0 = <&gpio_default>;
+
+	gpio {
+		gpio_default: gpio_default {
+			golden_mux {
+				/* Change unused pins to GPIO mode */
+				function = "gpio";
+				groups = "gpio3_a_1",	/* default: SysClkReq4 */
+					 "gpio14_a_1";	/* default: PWMOut1 */
+			};
+			golden_cfg1 {
+				pins = "GPIO11_B17", "GPIO13_D17", "GPIO50_L4";
+				bias-disable;
+			};
+		};
+	};
+};