dts: add device tree for STM32MP157C-ED1 board

Add minimal devicetree for STM32MP157C-ED1 board,
with only the devices to allow boot from SDCARD:
- RCC for clock and reset
- UART4 for console
- I2C and PMIC
- DDR
- SDMMC0 for SDCard

Waiting Kernel upstream for alignment.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/arch/arm/dts/stm32mp157c-ed1-u-boot.dtsi b/arch/arm/dts/stm32mp157c-ed1-u-boot.dtsi
new file mode 100644
index 0000000..94d27fb
--- /dev/null
+++ b/arch/arm/dts/stm32mp157c-ed1-u-boot.dtsi
@@ -0,0 +1,133 @@
+/*
+ * Copyright : STMicroelectronics 2018
+ *
+ * SPDX-License-Identifier:	GPL-2.0+	BSD-3-Clause
+ */
+
+#include <dt-bindings/clock/stm32mp1-clksrc.h>
+#include "stm32mp157-u-boot.dtsi"
+#include "stm32mp15-ddr3-2x4Gb-1066-binG.dtsi"
+
+/ {
+	aliases {
+		mmc0 = &sdmmc1;
+		i2c3 = &i2c4;
+	};
+};
+
+&uart4_pins_a {
+	u-boot,dm-pre-reloc;
+	pins1 {
+		u-boot,dm-pre-reloc;
+	};
+	pins2 {
+		u-boot,dm-pre-reloc;
+	};
+};
+
+&i2c4_pins_a {
+	u-boot,dm-pre-reloc;
+	pins {
+		u-boot,dm-pre-reloc;
+	};
+};
+
+&uart4 {
+	u-boot,dm-pre-reloc;
+};
+
+&i2c4 {
+	u-boot,dm-pre-reloc;
+};
+
+&pmic {
+	u-boot,dm-pre-reloc;
+};
+
+/* CLOCK init */
+&rcc_clk {
+	st,clksrc = <
+		CLK_MPU_PLL1P
+		CLK_AXI_PLL2P
+		CLK_MCU_PLL3P
+		CLK_PLL12_HSE
+		CLK_PLL3_HSE
+		CLK_PLL4_HSE
+		CLK_RTC_LSE
+		CLK_MCO1_DISABLED
+		CLK_MCO2_DISABLED
+	>;
+
+	st,clkdiv = <
+		1 /*MPU*/
+		0 /*AXI*/
+		0 /*MCU*/
+		1 /*APB1*/
+		1 /*APB2*/
+		1 /*APB3*/
+		1 /*APB4*/
+		2 /*APB5*/
+		23 /*RTC*/
+		0 /*MCO1*/
+		0 /*MCO2*/
+	>;
+
+	st,pkcs = <
+		CLK_CKPER_DISABLED
+		CLK_SDMMC12_PLL3R
+		CLK_I2C46_PCLK5
+		CLK_I2C12_PCLK1
+		CLK_I2C35_PCLK1
+		CLK_UART1_PCLK5
+		CLK_UART24_PCLK1
+		CLK_UART35_PCLK1
+		CLK_UART6_PCLK2
+		CLK_UART78_PCLK1
+	>;
+
+	/* VCO = 1300.0 MHz => P = 650 (CPU) */
+	pll1: st,pll@0 {
+		cfg = < 2 80 0 0 0 PQR(1,0,0) >;
+		frac = < 0x800 >;
+		u-boot,dm-pre-reloc;
+	};
+
+	/* VCO = 1066.0 MHz => P = 266 (AXI), Q = 533 (GPU), R = 533 (DDR) */
+	pll2: st,pll@1 {
+		cfg = < 2 65 1 0 0 PQR(1,1,1) >;
+		frac = < 0x1400 >;
+		u-boot,dm-pre-reloc;
+	};
+
+	/* VCO = 774.0 MHz => P = 194, Q = 37, R = 97 */
+	pll3: st,pll@2 {
+		cfg = < 3 128 3 20 7 PQR(1,1,1) >;
+		u-boot,dm-pre-reloc;
+	};
+
+	/* VCO = 508.0 MHz => P = 56, Q = 56, R = 56 */
+	pll4: st,pll@3 {
+		cfg = < 5 126 8 8 8 PQR(1,1,1) >;
+		u-boot,dm-pre-reloc;
+	};
+};
+
+/* SPL part **************************************/
+/* MMC1 boot */
+&sdmmc1_b4_pins_a {
+	u-boot,dm-spl;
+	pins {
+		u-boot,dm-spl;
+	};
+};
+
+&sdmmc1_dir_pins_a {
+	u-boot,dm-spl;
+	pins {
+		u-boot,dm-spl;
+	};
+};
+
+&sdmmc1 {
+	u-boot,dm-spl;
+};