diff mbox series

[4/8] db820c: add qualcomm dragonboard 820C support

Message ID 1513252441-29520-4-git-send-email-jorge.ramirez-ortiz@linaro.org
State Superseded
Headers show
Series [1/8] env: enable accessing the environment in an EXT4 partition | expand

Commit Message

Jorge Ramirez-Ortiz Dec. 14, 2017, 11:53 a.m. UTC
This commit adds support for 96Boards Dragonboard820C.

The board is based on APQ8086 Qualcomm Soc, complying with the
96Boards specification.

Features
 - 4x Kyro CPU (64 bit) up to 2.15GHz
 - USB2.0
 - USB3.0
 - ISP
 - Qualcomm Hexagon DSP
 - SD 3.0 (UHS-I)
 - UFS 2.0
 - Qualcomm Adreno 530 GPU
 - GPS
 - BT 4.2
 - Wi-Fi 2.4GHz, 5GHz (802.11ac)
 - PCIe 2.0
 - MIPI-CSI, MIPI-DSI
 - I2S

U-Boot boots chained from LK (LK implements the fastboot protocol) in
64-bit mode.

For detailed build instructions see readme.txt in the board directory.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
---
 arch/arm/dts/Makefile                              |   3 +-
 arch/arm/dts/dragonboard820c.dts                   |  65 +++
 arch/arm/mach-snapdragon/Kconfig                   |  10 +
 arch/arm/mach-snapdragon/Makefile                  |   2 +
 arch/arm/mach-snapdragon/clock-apq8096.c           |  62 +++
 .../mach-snapdragon/include/mach/sysmap-apq8096.h  |  29 ++
 arch/arm/mach-snapdragon/sysmap-apq8096.c          |  32 ++
 board/qualcomm/dragonboard820c/Kconfig             |  15 +
 board/qualcomm/dragonboard820c/MAINTAINERS         |   6 +
 board/qualcomm/dragonboard820c/Makefile            |   8 +
 board/qualcomm/dragonboard820c/dragonboard820c.c   | 128 ++++++
 board/qualcomm/dragonboard820c/head.S              |  34 ++
 board/qualcomm/dragonboard820c/readme.txt          | 463 +++++++++++++++++++++
 board/qualcomm/dragonboard820c/u-boot.lds          | 106 +++++
 configs/dragonboard820c_defconfig                  |  37 ++
 include/configs/dragonboard820c.h                  |  72 ++++
 16 files changed, 1071 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/dts/dragonboard820c.dts
 create mode 100644 arch/arm/mach-snapdragon/clock-apq8096.c
 create mode 100644 arch/arm/mach-snapdragon/include/mach/sysmap-apq8096.h
 create mode 100644 arch/arm/mach-snapdragon/sysmap-apq8096.c
 create mode 100644 board/qualcomm/dragonboard820c/Kconfig
 create mode 100644 board/qualcomm/dragonboard820c/MAINTAINERS
 create mode 100644 board/qualcomm/dragonboard820c/Makefile
 create mode 100644 board/qualcomm/dragonboard820c/dragonboard820c.c
 create mode 100644 board/qualcomm/dragonboard820c/head.S
 create mode 100644 board/qualcomm/dragonboard820c/readme.txt
 create mode 100644 board/qualcomm/dragonboard820c/u-boot.lds
 create mode 100644 configs/dragonboard820c_defconfig
 create mode 100644 include/configs/dragonboard820c.h
diff mbox series

Patch

diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index ed85349..df85e71 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -211,7 +211,8 @@  dtb-$(CONFIG_FSL_LSCH2) += fsl-ls1043a-qds-duart.dtb \
 	fsl-ls1012a-rdb.dtb \
 	fsl-ls1012a-frdm.dtb
 
-dtb-$(CONFIG_ARCH_SNAPDRAGON) += dragonboard410c.dtb
+dtb-$(CONFIG_TARGET_DRAGONBOARD410C) += dragonboard410c.dtb
+dtb-$(CONFIG_TARGET_DRAGONBOARD820C) += dragonboard820c.dtb
 
 dtb-$(CONFIG_STM32F7) += stm32f746-disco.dtb \
 	stm32f769-disco.dtb
diff --git a/arch/arm/dts/dragonboard820c.dts b/arch/arm/dts/dragonboard820c.dts
new file mode 100644
index 0000000..bad5a1e
--- /dev/null
+++ b/arch/arm/dts/dragonboard820c.dts
@@ -0,0 +1,65 @@ 
+/*
+ * Qualcomm APQ8096 based Dragonboard 820C board device tree source
+ *
+ * (C) Copyright 2017 Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/dts-v1/;
+
+#include "skeleton64.dtsi"
+
+/ {
+	model = "Qualcomm Technologies, Inc. DB820c";
+	compatible = "arrow,apq8096-db820c", "qcom,apq8096-sbc";
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	aliases {
+		serial0 = &blsp2_uart1;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory {
+		device_type = "memory";
+		reg = <0 0x80000000 0 0xc0000000>;
+	};
+
+	psci {
+		compatible = "arm,psci-1.0";
+		method = "smc";
+	};
+
+	soc: soc {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0 0 0xffffffff>;
+		compatible = "simple-bus";
+
+		gcc: clock-controller@300000 {
+			compatible = "qcom,gcc-msm8996";
+			#clock-cells = <1>;
+			#reset-cells = <1>;
+			#power-domain-cells = <1>;
+			reg = <0x300000 0x90000>;
+		};
+
+		blsp2_uart1: serial@75b0000 {
+			compatible = "qcom,msm-uartdm-v1.4", "qcom,msm-uartdm";
+			reg = <0x75b0000 0x1000>;
+		};
+
+		sdhc2: sdhci@74a4900 {
+			 compatible = "qcom,sdhci-msm-v4";
+			 reg = <0x74a4900 0x314>, <0x74a4000 0x800>;
+       		 index = <0x0>;
+			 bus-width = <4>;
+			 clock = <&gcc 0>;
+	                 clock-frequency = <200000000>;
+		 };
+	};
+};
diff --git a/arch/arm/mach-snapdragon/Kconfig b/arch/arm/mach-snapdragon/Kconfig
index dc7ba21..d55dc1a 100644
--- a/arch/arm/mach-snapdragon/Kconfig
+++ b/arch/arm/mach-snapdragon/Kconfig
@@ -19,8 +19,18 @@  config TARGET_DRAGONBOARD410C
 	  - HDMI
 	  - 20-pin low speed and 40-pin high speed expanders, 4 LED, 3 buttons
 
+config TARGET_DRAGONBOARD820C
+	bool "96Boards Dragonboard 820C"
+	help
+	  Support for 96Boards Dragonboard 820C. This board complies with
+	  96Board Open Platform Specifications. Features:
+	  - Qualcomm Snapdragon 820C SoC - APQ8096 (4xKyro CPU)
+	  - 3GiB RAM
+	  - 32GiB UFS drive
+
 endchoice
 
 source "board/qualcomm/dragonboard410c/Kconfig"
+source "board/qualcomm/dragonboard820c/Kconfig"
 
 endif
diff --git a/arch/arm/mach-snapdragon/Makefile b/arch/arm/mach-snapdragon/Makefile
index 74f90dc..7f35c79 100644
--- a/arch/arm/mach-snapdragon/Makefile
+++ b/arch/arm/mach-snapdragon/Makefile
@@ -4,6 +4,8 @@ 
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+obj-$(CONFIG_TARGET_DRAGONBOARD820C) += clock-apq8096.o
+obj-$(CONFIG_TARGET_DRAGONBOARD820C) += sysmap-apq8096.o
 obj-$(CONFIG_TARGET_DRAGONBOARD410C) += clock-apq8016.o
 obj-$(CONFIG_TARGET_DRAGONBOARD410C) += sysmap-apq8016.o
 obj-y += clock-snapdragon.o
diff --git a/arch/arm/mach-snapdragon/clock-apq8096.c b/arch/arm/mach-snapdragon/clock-apq8096.c
new file mode 100644
index 0000000..3224812
--- /dev/null
+++ b/arch/arm/mach-snapdragon/clock-apq8096.c
@@ -0,0 +1,62 @@ 
+/*
+ * Clock drivers for Qualcomm APQ8096
+ *
+ * (C) Copyright 2017 Jorge Ramirez Ortiz <jorge.ramirez-ortiz@linaro.org>
+ *
+ * Based on Little Kernel driver, simplified
+ *
+ * SPDX-License-Identifier:	BSD-3-Clause
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <linux/bitops.h>
+#include "clock-snapdragon.h"
+
+/* GPLL0 clock control registers */
+#define GPLL0_STATUS_ACTIVE		BIT(30)
+#define APCS_GPLL_ENA_VOTE_GPLL0 	BIT(0)
+
+static const struct bcr_regs sdc_regs = {
+	.cfg_rcgr = SDCC2_CFG_RCGR,
+	.cmd_rcgr = SDCC2_CMD_RCGR,
+	.M = SDCC2_M,
+	.N = SDCC2_N,
+	.D = SDCC2_D,
+};
+
+static const struct gpll0_ctrl gpll0_ctrl = {
+	.status = GPLL0_STATUS,
+	.status_bit = GPLL0_STATUS_ACTIVE,
+	.ena_vote = APCS_GPLL_ENA_VOTE,
+	.vote_bit = APCS_GPLL_ENA_VOTE_GPLL0,
+};
+
+static int clk_init_sdc(struct msm_clk_priv *priv, uint rate)
+{
+	int div = 3;
+
+	clk_enable_cbc(priv->base + SDCC2_AHB_CBCR);
+	clk_rcg_set_rate_mnd(priv->base, &sdc_regs, div, 0, 0,
+		             CFG_CLK_SRC_GPLL0);
+	clk_enable_gpll0(priv->base, &gpll0_ctrl);
+	clk_enable_cbc(priv->base + SDCC2_APPS_CBCR);
+
+	return rate;
+}
+
+ulong msm_set_rate(struct clk *clk, ulong rate)
+{
+	struct msm_clk_priv *priv = dev_get_priv(clk->dev);
+
+	switch (clk->id) {
+	case 0: /* SDC1 */
+		return clk_init_sdc(priv, rate);
+		break;
+	default:
+		return 0;
+	}
+}
diff --git a/arch/arm/mach-snapdragon/include/mach/sysmap-apq8096.h b/arch/arm/mach-snapdragon/include/mach/sysmap-apq8096.h
new file mode 100644
index 0000000..fb89de2
--- /dev/null
+++ b/arch/arm/mach-snapdragon/include/mach/sysmap-apq8096.h
@@ -0,0 +1,29 @@ 
+/*
+ * Qualcomm APQ8096 sysmap
+ *
+ * (C) Copyright 2017 Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#ifndef _MACH_SYSMAP_APQ8096_H
+#define _MACH_SYSMAP_APQ8096_H
+
+#define TLMM_BASE_ADDR			(0x1010000)
+
+/* Strength (sdc1) */
+#define SDC1_HDRV_PULL_CTL_REG		(TLMM_BASE_ADDR + 0x0012D000)
+
+/* Clocks: (from CLK_CTL_BASE)  */
+#define GPLL0_STATUS			(0x0000)
+#define APCS_GPLL_ENA_VOTE		(0x52000)
+
+#define SDCC2_BCR			(0x14000) /* block reset */
+#define SDCC2_APPS_CBCR			(0x14004) /* branch control */
+#define SDCC2_AHB_CBCR			(0x14008)
+#define SDCC2_CMD_RCGR			(0x14010)
+#define SDCC2_CFG_RCGR			(0x14014)
+#define SDCC2_M				(0x14018)
+#define SDCC2_N				(0x1401C)
+#define SDCC2_D				(0x14020)
+
+#endif
diff --git a/arch/arm/mach-snapdragon/sysmap-apq8096.c b/arch/arm/mach-snapdragon/sysmap-apq8096.c
new file mode 100644
index 0000000..cb6d1e4
--- /dev/null
+++ b/arch/arm/mach-snapdragon/sysmap-apq8096.c
@@ -0,0 +1,32 @@ 
+/*
+ * Qualcomm APQ8096 memory map
+ *
+ * (C) Copyright 2017 Jorge Ramirez Ortiz <jorge.ramirez-ortiz@linaro.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/armv8/mmu.h>
+
+static struct mm_region apq8096_mem_map[] = {
+	{
+		.virt = 0x0UL, /* Peripheral block */
+		.phys = 0x0UL, /* Peripheral block */
+		.size = 0x10000000UL,
+		.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
+			 PTE_BLOCK_NON_SHARE |
+			 PTE_BLOCK_PXN | PTE_BLOCK_UXN
+	}, {
+		.virt = 0x80000000UL, /* DDR */
+		.phys = 0x80000000UL, /* DDR */
+		.size = 0xC0000000UL,
+		.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
+			 PTE_BLOCK_INNER_SHARE
+	}, {
+		/* List terminator */
+		0,
+	}
+};
+
+struct mm_region *mem_map = apq8096_mem_map;
diff --git a/board/qualcomm/dragonboard820c/Kconfig b/board/qualcomm/dragonboard820c/Kconfig
new file mode 100644
index 0000000..aff9af5
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/Kconfig
@@ -0,0 +1,15 @@ 
+if TARGET_DRAGONBOARD820C
+
+config SYS_BOARD
+	default "dragonboard820c"
+
+config SYS_VENDOR
+	default "qualcomm"
+
+config SYS_SOC
+	default "apq8096"
+
+config SYS_CONFIG_NAME
+	default "dragonboard820c"
+
+endif
diff --git a/board/qualcomm/dragonboard820c/MAINTAINERS b/board/qualcomm/dragonboard820c/MAINTAINERS
new file mode 100644
index 0000000..a157033
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/MAINTAINERS
@@ -0,0 +1,6 @@ 
+DRAGONBOARD820C BOARD
+M:	Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
+S:	Maintained
+F:	board/qualcomm/dragonboard820c/
+F:	include/configs/dragonboard820c.h
+F:	configs/dragonboard820c_defconfig
diff --git a/board/qualcomm/dragonboard820c/Makefile b/board/qualcomm/dragonboard820c/Makefile
new file mode 100644
index 0000000..a1ce4b2
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/Makefile
@@ -0,0 +1,8 @@ 
+#
+# (C) Copyright 2017 Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y	:= dragonboard820c.o
+extra-y += head.o
diff --git a/board/qualcomm/dragonboard820c/dragonboard820c.c b/board/qualcomm/dragonboard820c/dragonboard820c.c
new file mode 100644
index 0000000..8f40ba4
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/dragonboard820c.c
@@ -0,0 +1,128 @@ 
+/*
+ * Board init file for Dragonboard 820C
+ *
+ * (C) Copyright 2017 Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@gmail.com>	
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <asm/arch/sysmap-apq8096.h>
+#include <linux/arm-smccc.h>
+#include <linux/psci.h>
+#include <common.h>
+#include <dm.h>
+#include <asm/io.h>
+#include <linux/bitops.h>
+#include <asm/psci.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int dram_init(void)
+{
+	gd->ram_size = PHYS_SDRAM_SIZE;
+
+	return 0;
+}
+
+int dram_init_banksize(void)
+{
+	gd->bd->bi_dram[0].start = PHYS_SDRAM_1;
+	gd->bd->bi_dram[0].size = PHYS_SDRAM_1_SIZE;
+
+	gd->bd->bi_dram[1].start = PHYS_SDRAM_2;
+	gd->bd->bi_dram[1].size  = PHYS_SDRAM_2_SIZE;
+
+	return 0;
+}
+
+static void sdhci_power_init(void)
+{
+	const uint32_t TLMM_PULL_MASK = 0x3;
+	const uint32_t TLMM_HDRV_MASK = 0x7;
+
+	struct tlmm_cfg {
+		uint32_t bit;  /* bit in the register      */
+		uint8_t mask;  /* mask clk/dat/cmd control */
+		uint8_t val;
+	};
+
+	/* bit offsets in the sdc tlmm register */
+	enum {  SDC1_DATA_HDRV = 0,
+		SDC1_CMD_HDRV  = 3,
+		SDC1_CLK_HDRV  = 6,
+		SDC1_DATA_PULL = 9,
+		SDC1_CMD_PULL  = 11,
+		SDC1_CLK_PULL  = 13,
+		SDC1_RCLK_PULL = 15,
+	};
+
+	enum {  TLMM_PULL_DOWN	 = 0x1,
+		TLMM_PULL_UP   = 0x3,
+		TLMM_NO_PULL   = 0x0,
+	};
+
+	enum {  TLMM_CUR_VAL_10MA = 0x04,
+		TLMM_CUR_VAL_16MA = 0x07,
+	};
+	int i;
+
+	/* drive strength configs for sdhc pins */
+	const struct tlmm_cfg hdrv[] =
+	{
+		{ SDC1_CLK_HDRV,  TLMM_CUR_VAL_16MA, TLMM_HDRV_MASK, },
+		{ SDC1_CMD_HDRV,  TLMM_CUR_VAL_10MA, TLMM_HDRV_MASK, },
+		{ SDC1_DATA_HDRV, TLMM_CUR_VAL_10MA, TLMM_HDRV_MASK, },
+	};
+
+	/* pull configs for sdhc pins */
+	const struct tlmm_cfg pull[] =
+	{
+		{ SDC1_CLK_PULL,  TLMM_NO_PULL, TLMM_PULL_MASK, },
+		{ SDC1_CMD_PULL,  TLMM_PULL_UP, TLMM_PULL_MASK, },
+		{ SDC1_DATA_PULL, TLMM_PULL_UP, TLMM_PULL_MASK, },
+	};
+
+	const struct tlmm_cfg rclk[] =
+	{
+		{ SDC1_RCLK_PULL, TLMM_PULL_DOWN, TLMM_PULL_MASK,},
+	};
+
+	for (i = 0; i < ARRAY_SIZE(hdrv); i++)
+		clrsetbits_le32(SDC1_HDRV_PULL_CTL_REG,
+			hdrv[i].mask << hdrv[i].bit,
+			hdrv[i].val  << hdrv[i].bit);
+
+	for (i = 0; i < ARRAY_SIZE(pull); i++)
+		clrsetbits_le32(SDC1_HDRV_PULL_CTL_REG,
+			pull[i].mask << pull[i].bit,
+			pull[i].val  << pull[i].bit);
+
+	for (i = 0; i < ARRAY_SIZE(rclk); i++)
+		clrsetbits_le32(SDC1_HDRV_PULL_CTL_REG,
+			rclk[i].mask << rclk[i].bit,
+			rclk[i].val  << rclk[i].bit);
+}
+
+static void show_psci_version(void)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(ARM_PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0, 0, 0, 0, 0, &res);
+
+	printf("PSCI:  v%ld.%ld\n",
+		PSCI_VERSION_MAJOR(res.a0),
+		PSCI_VERSION_MINOR(res.a0));
+}
+
+int board_init(void)
+{
+	sdhci_power_init();
+	show_psci_version();
+
+	return 0;
+}
+
+void reset_cpu(ulong addr)
+{
+	psci_system_reset();
+}
diff --git a/board/qualcomm/dragonboard820c/head.S b/board/qualcomm/dragonboard820c/head.S
new file mode 100644
index 0000000..06d82d5
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/head.S
@@ -0,0 +1,34 @@ 
+/*
+ * ARM64 header for proper chain-loading with Little Kernel.
+ *
+ * Little Kernel shipped with Dragonboard820C boots standard Linux images for
+ * ARM64. This file adds header that is required to boot U-Boot properly.
+ *
+ * For details see:
+ * https://www.kernel.org/doc/Documentation/arm64/booting.txt
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <config.h>
+
+/*
+ *   per document in linux/Doc/arm64/booting.text
+ */
+.global _arm64_header
+_arm64_header:
+	b _start
+	.word 0
+	.quad   CONFIG_SYS_TEXT_BASE-PHYS_SDRAM_1 /* Image load offset, LE */
+	.quad   0    /* Effective size of kernel image, little-endian */
+	.quad   0    /* kernel flags, little-endian */
+	.quad   0    /* reserved */
+	.quad   0    /* reserved */
+	.quad   0    /* reserved */
+	.byte   0x41 /* Magic number, "ARM\x64" */
+	.byte   0x52
+	.byte   0x4d
+	.byte   0x64
+	.word   0    /* reserved (used for PE COFF offset) */
diff --git a/board/qualcomm/dragonboard820c/readme.txt b/board/qualcomm/dragonboard820c/readme.txt
new file mode 100644
index 0000000..88adb85
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/readme.txt
@@ -0,0 +1,463 @@ 
+#
+# (C) Copyright 2017 Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+================================================================================
+             What is working (enough to boot a distro from SD card)
+================================================================================
+   - UART
+   - SD card
+   - PSCI reset
+   - Environment in EXT4 partition 1 in SD card (check defconfig for details)
+         dont forget to insert the card in the SD slot before booting if you
+         are going to make mods to the environment
+
+================================================================================
+                     Build & Run instructions
+================================================================================
+
+1) Install mkbootimg and dtbTool from Codeaurora:
+
+   git://codeaurora.org/quic/kernel/skales
+   commit 8492547e404e969262d9070dee9bdd15668bb70f worked for me.
+
+2) Setup CROSS_COMPILE to aarch64 compiler or if you use ccache just do
+   CROSS_COMPILE="ccache aarch64-linux-gnu-"
+
+3) cd to the u-boot tree
+
+  $ make dragonboard820c_config
+  $ make -j `nproc`
+
+4) generate fake, empty ramdisk (can have 0 bytes)
+
+   $ touch rd
+
+5) Generate qualcomm device tree table with dtbTool
+
+   $ dtbTool -o dt.img arch/arm/dts
+
+6) Generate Android boot image with mkbootimg:
+
+   $ mkbootimg --kernel=u-boot-dtb.bin             \
+               --output=u-boot.img                 \
+               --dt=dt.img                         \
+               --pagesize 4096                     \
+               --base 0x80000000                   \
+               --ramdisk=rd                        \
+               --cmdline=""
+
+7) Reboot the board into fastboot mode
+   - plug the board micro-usb to your laptop usb host.
+   - reboot the board with vol- button pressed
+
+8) Boot the uboot image using fastboot
+
+   $ fastboot boot u-boot.img
+
+   or flash it to the UFS drive boot partition:
+
+   $ fastboot flash boot u-boot.img
+   $ fastboot reboot
+
+
+================================================================================
+      To boot a linux kernel from SDHCI with the ROOTFS on an NFS share:
+================================================================================
+
+1) create an EXT4 partition on the SD card (must be partition #1)
+
+2) build the kernel image and dtb  (documented extensively somewhere else)
+
+3) copy the drivers to the NFS partition (ie: 192.168.1.2 /exports/db820c-rootfs)
+
+4) add the u-boot headers to the image:
+
+    $ mkimage -A arm64                                     \
+              -O linux                                     \
+              -C none                                      \
+              -T kernel                                    \
+              -a 0x80080000                                \
+              -e 0x80080000                                \
+              -n Dragonboard820c                           \
+              -d $kernel/arch/arm64/boot/Image             \
+              uImage
+
+5) copy the generated uImage and the device tree binary to the SD card EXT4
+   partition
+
+    $ cp uImage /mnt/boot/
+    $ cp apq8096-db820c.dtb /mnt/boot/
+
+6) on the SD card create /extlinux/extlinux.conf  as follows:
+
+   default nfs
+   prompt 1
+   timeout 10
+
+   LABEL nfs
+      MENU NFS entry
+      LINUX /uImage
+      FDT /apq8096-db820c.dtb
+      APPEND root=/dev/nfs rw                                         \
+             nfsroot=192.168.1.2:/exports/db829c-rootfs,v3,tcp        \
+             rootwait                                                 \
+             ip=dhcp consoleblank=0                                   \
+             console=tty0                                             \
+             console=ttyMSM0,115200n8                                 \
+             earlyprintk earlycon=msm_serial_dm,0x75b0000             \
+             androidboot.bootdevice=624000.ufshc                      \
+             androidboot.verifiedbootstate=orange                     \
+             androidboot.ver0
+
+7) remove the SD card from the laptop and insert it back to the db820 board.
+   the SD card EXT4 partition#1 should contain:
+      /uImage
+      /apq8096-db820c.dtb
+      /extlinux/extlinux.conf
+
+8) reboot the db820 board
+
+================================================================================
+                    Successful boot sequence
+================================================================================
+
+Format: Log Type - Time(microsec) - Message - Optional Info
+Log Type: B - Since Boot(Power On Reset),  D - Delta,  S - Statistic
+S - QC_IMAGE_VERSION_STRING=BOOT.XF.1.0-00301
+S - IMAGE_VARIANT_STRING=M8996LAB
+S - OEM_IMAGE_VERSION_STRING=crm-ubuntu68
+S - Boot Interface: UFS
+S - Secure Boot: Off
+S - Boot Config @ 0x00076044 = 0x000001c9
+S - JTAG ID @ 0x000760f4 = 0x4003e0e1
+S - OEM ID @ 0x000760f8 = 0x00000000
+S - Serial Number @ 0x00074138 = 0x2e8844ce
+S - OEM Config Row 0 @ 0x00074188 = 0x0000000000000000
+S - OEM Config Row 1 @ 0x00074190 = 0x0000000000000000
+S - Feature Config Row 0 @ 0x000741a0 = 0x0050000010000100
+S - Feature Config Row 1 @ 0x000741a8 = 0x00fff00001ffffff
+S - Core 0 Frequency, 1228 MHz
+B -         0 - PBL, Start
+B -     10412 - bootable_media_detect_entry, Start
+B -     47480 - bootable_media_detect_success, Start
+B -     47481 - elf_loader_entry, Start
+B -     49027 - auth_hash_seg_entry, Start
+B -     49129 - auth_hash_seg_exit, Start
+B -     82403 - elf_segs_hash_verify_entry, Start
+B -     84905 - PBL, End
+B -     86955 - SBL1, Start
+B -    182969 - usb: hs_phy_nondrive_start
+B -    183305 - usb: PLL lock success - 0x3
+B -    186294 - usb: hs_phy_nondrive_finish
+B -    190442 - boot_flash_init, Start
+D -        30 - boot_flash_init, Delta
+B -    197548 - sbl1_ddr_set_default_params, Start
+D -        30 - sbl1_ddr_set_default_params, Delta
+B -    205509 - boot_config_data_table_init, Start
+D -    200659 - boot_config_data_table_init, Delta - (60 Bytes)
+B -    410713 - CDT Version:3,Platform ID:24,Major ID:1,Minor ID:0,Subtype:0
+B -    415410 - Image Load, Start
+D -     22570 - PMIC Image Loaded, Delta - (37272 Bytes)
+B -    437980 - pm_device_init, Start
+B -    443744 - PON REASON:PM0:0x200000061 PM1:0x200000021
+B -    480161 - PM_SET_VAL:Skip
+D -     40016 - pm_device_init, Delta
+B -    482083 - pm_driver_init, Start
+D -      2928 - pm_driver_init, Delta
+B -    488671 - pm_sbl_chg_init, Start
+D -        91 - pm_sbl_chg_init, Delta
+B -    495442 - vsense_init, Start
+D -         0 - vsense_init, Delta
+B -    505171 - Pre_DDR_clock_init, Start
+D -       396 - Pre_DDR_clock_init, Delta
+B -    509045 - ddr_initialize_device, Start
+B -    512766 - 8996 v3.x detected, Max frequency = 1.8 GHz
+B -    522373 - ddr_initialize_device, Delta
+B -    522404 - DDR ID, Rank 0, Rank 1, 0x6, 0x300, 0x300
+B -    526247 - Basic DDR tests done
+B -    594994 - clock_init, Start
+D -       274 - clock_init, Delta
+B -    598349 - Image Load, Start
+D -      4331 - QSEE Dev Config Image Loaded, Delta - (46008 Bytes)
+B -    603808 - Image Load, Start
+D -      5338 - APDP Image Loaded, Delta - (0 Bytes)
+B -    612409 - usb: UFS Serial - 2f490ecf
+B -    616801 - usb: fedl, vbus_low
+B -    620431 - Image Load, Start
+D -     55418 - QSEE Image Loaded, Delta - (1640572 Bytes)
+B -    675849 - Image Load, Start
+D -      2013 - SEC Image Loaded, Delta - (4096 Bytes)
+B -    683413 - sbl1_efs_handle_cookies, Start
+D -       457 - sbl1_efs_handle_cookies, Delta
+B -    691892 - Image Load, Start
+D -     14396 - QHEE Image Loaded, Delta - (254184 Bytes)
+B -    706319 - Image Load, Start
+D -     14061 - RPM Image Loaded, Delta - (223900 Bytes)
+B -    721111 - Image Load, Start
+D -      3233 - STI Image Loaded, Delta - (0 Bytes)
+B -    727913 - Image Load, Start
+D -     34709 - APPSBL Image Loaded, Delta - (748716 Bytes)
+B -    762713 - SBL1, End
+D -    680028 - SBL1, Delta
+S - Flash Throughput, 94000 KB/s  (2959024 Bytes,  31250 us)
+S - DDR Frequency, 1017 MHz
+Android Bootloader - UART_DM Initialized!!!
+
+[0] BUILD_VERSION=
+[0] BUILD_DATE=16:07:51 - Nov 17 2017
+[0] welcome to lk
+[10] platform_init()
+[10] target_init()
+[10] RPM GLink Init
+[10] Opening RPM Glink Port success
+[10] Opening SSR Glink Port success
+[20] Glink Connection between APPS and RPM established
+[20] Glink Connection between APPS and RPM established
+[40] UFS init success
+[80] Qseecom Init Done in Appsbl
+[80] secure app region addr=0x86600000 size=0x2200000[90] TZ App region notif returned with status:0 addr:86600000 size:35651584
+[100] TZ App log region register returned with status:0 addr:916d4000 size:4096
+[100] Qseecom TZ Init Done in Appsbl
+[120] Loading cmnlib done
+[120] qseecom_start_app: Loading app keymaster for the first time
+[150] <8>keymaster: "\"KEYMASTER Init \""
+[160] Selected panel: none
+Skip panel configuration
+[160] pm8x41_get_is_cold_boot: cold boot
+[170] boot_verifier: Device is in ORANGE boot state.
+[180] Device is unlocked! Skipping verification...
+[180] Loading (boot) image (348160): start
+[190] Loading (boot) image (348160): done
+[190] use_signed_kernel=1, is_unlocked=1, is_tampered=0.
+[200] Your device has been unlocked and cant be trusted.
+Wait for 5 seconds before proceeding
+
+[5200] mdtp: mdtp_img loaded
+[5210] mdtp: is_test_mode: test mode is set to 1
+[5210] mdtp: read_metadata: SUCCESS
+[5230] LK SEC APP Handle: 0x1
+[5230] Return value from recv_data: 14
+[5240] Return value from recv_data: 14
+[5250] Return value from recv_data: 14
+[5260] DTB Total entry: 1, DTB version: 3
+[5260] Using DTB entry 0x00000123/00000000/0x00000018/0 for device 0x00000123/00030001/0x00010018/0
+[5270] cmdline:  androidboot.bootdevice=624000.ufshc androidboot.verifiedbootstate=orange androidboot.veritymode=enforcing androidboot.serialno=2f490ecf androidboot.baseband=apq mdss_mdp.panel=0
+[5290] Updating device tree: start
+[5290] Updating device tree: done
+[5290] Return value from recv_data: 14
+[5300] RPM GLINK UnInit
+[5300] Qseecom De-Init Done in Appsbl
+[5300] booting linux @ 0x80080000, ramdisk @ 0x82200000 (0), tags/device tree @ 0x82000000
+[5310] Jumping to kernel via monitor
+
+U-Boot 2017.11-00145-ge895117 (Nov 29 2017 - 10:04:06 +0100)
+Qualcomm-DragonBoard 820C
+
+DRAM:  3 GiB
+PSCI:  v1.0
+MMC:   sdhci@74a4900: 0
+In:    serial@75b0000
+Out:   serial@75b0000
+Err:   serial@75b0000
+Net:   Net Initialization Skipped
+No ethernet found.
+Hit any key to stop autoboot:  0
+switch to partitions #0, OK
+mmc0 is current device
+Scanning mmc 0:1...
+Found /extlinux/extlinux.conf
+Retrieving file: /extlinux/extlinux.conf
+433 bytes read in 71 ms (5.9 KiB/s)
+1:      nfs root
+
+Retrieving file: /uImage
+19397184 bytes read in 2024 ms (9.1 MiB/s)
+append: root=/dev/nfs rw nfsroot=192.168.1.2:/db820c/rootfs,v3,tcp rootwait ip=dhcp consoleblank=0 console=tty0 console=ttyMSM0,115200n8 earlyprintk earlycon=msm_serial_dm,0x75b0000 androidboot.bootdevice=624000.ufshc androidboot.verifiedbootstate=orange androidboot.ver0
+
+Retrieving file: /apq8096-db820c.dtb
+38134 bytes read in 37 ms (1005.9 KiB/s)
+
+## Booting kernel from Legacy Image at 95000000 ...
+   Image Name:   Dragonboard820c
+   Image Type:   AArch64 Linux Kernel Image (uncompressed)
+   Data Size:    19397120 Bytes = 18.5 MiB
+   Load Address: 80080000
+   Entry Point:  80080000
+   Verifying Checksum ... OK
+## Flattened Device Tree blob at 93000000
+   Booting using the fdt blob at 0x93000000
+   Loading Kernel Image ... OK
+   Using Device Tree in place at 0000000093000000, end 000000009300c4f5
+
+Starting kernel ...
+
+[    0.000000] Booting Linux on physical CPU 0x0
+[    0.000000] Linux version 4.11.3-30039-g5a922a1 (jramirez@igloo) (gcc version 6.3.1 20170404 (Linaro GCC 6.3-2017.05) ) #1 SMP PREEMPT Wed Oct 18 10:21:11 CEST 2017
+[    0.000000] Boot CPU: AArch64 Processor [511f2112]
+[    0.000000] earlycon: msm_serial_dm0 at MMIO 0x00000000075b0000 (options '')
+[    0.000000] bootconsole [msm_serial_dm0] enabled
+[    0.000000] efi: Getting EFI parameters from FDT:
+[    0.000000] efi: UEFI not found.
+[    0.000000] OF: reserved mem: OVERLAP DETECTED!
+[    0.000000] adsp@8ea00000 (0x000000008ea00000--0x0000000090400000) overlaps with gpu@8f200000 (0x000000008f200000--0x000000008f300000)
+[    0.000000] Reserved memory: created DMA memory pool at 0x000000008f200000, size 1 MiB
+[    0.000000] OF: reserved mem: initialized node gpu@8f200000, compatible id shared-dma-pool
+[    0.000000] Reserved memory: created DMA memory pool at 0x0000000090400000, size 8 MiB
+[    0.000000] OF: reserved mem: initialized node venus@90400000, compatible id shared-dma-pool
+[    0.000000] cma: Reserved 128 MiB at 0x00000000b8000000
+[    0.000000] NUMA: No NUMA configuration found
+[    0.000000] NUMA: Faking a node at [mem 0x0000000000000000-0x00000000bfffffff]
+[    0.000000] NUMA: Adding memblock [0x80000000 - 0x857fffff] on node 0
+[    0.000000] NUMA: Adding memblock [0x91800000 - 0xbfffffff] on node 0
+[    0.000000] NUMA: Initmem setup node 0 [mem 0x80000000-0xbfffffff]
+[    0.000000] NUMA: NODE_DATA [mem 0xb7fb6680-0xb7fb817f]
+[    0.000000] Zone ranges:
+[    0.000000]   DMA      [mem 0x0000000080000000-0x00000000bfffffff]
+[    0.000000]   Normal   empty
+[    0.000000] Movable zone start for each node
+[    0.000000] Early memory node ranges
+[    0.000000]   node   0: [mem 0x0000000080000000-0x00000000857fffff]
+[    0.000000]   node   0: [mem 0x0000000091800000-0x00000000bfffffff]
+[    0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x00000000bfffffff]
+[    0.000000] psci: probing for conduit method from DT.
+[    0.000000] psci: PSCIv1.0 detected in firmware.
+[    0.000000] psci: Using standard PSCI v0.2 function IDs
+[    0.000000] psci: MIGRATE_INFO_TYPE not supported.
+[    0.000000] percpu: Embedded 23 pages/cpu @ffff8000de9a3000 s57240 r8192 d28776 u94208
+[    0.000000] pcpu-alloc: s57240 r8192 d28776 u94208 alloc=23*4096
+[    0.000000] pcpu-alloc: [0] 0 [0] 1 [0] 2 [0] 3
+[    0.000000] Detected PIPT I-cache on CPU0
+[    0.000000] Built 1 zonelists in Node order, mobility grouping on.  Total pages: 720293
+[    0.000000] Policy zone: Normal
+[    0.000000] Kernel command line: root=/dev/nfs rw nfsroot=192.168.1.2:/db820c/rootfs,v3,tcp rootwait ip=dhcp consoleblank=0
+console=tty0 console=ttyMSM0,115200n8 earlyprintk earlycon=msm_serial_dm,0x75b0000 androidboot.bootdevice=624000.ufshc androidboot.verifiedbootstate=orange a
+ndroidboot.ver0
+[    0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes)
+[    0.000000] software IO TLB [mem 0xd3fff000-0xd7fff000] (64MB) mapped at [ffff800053fff000-ffff800057ffefff]
+[    0.000000] Memory: 2644172K/2926908K available (11196K kernel code, 1470K rwdata, 5132K rodata, 1088K init, 449K bss, 151664K reserved, 131072K cma-reser
+ved)
+[    0.000000] Virtual kernel memory layout:
+[    0.000000]     modules : 0xffff000000000000 - 0xffff000008000000   (   128 MB)
+[    0.000000]     vmalloc : 0xffff000008000000 - 0xffff7dffbfff0000   (129022 GB)
+[    0.000000]       .text : 0xffff000008080000 - 0xffff000008b70000   ( 11200 KB)
+[    0.000000]     .rodata : 0xffff000008b70000 - 0xffff000009080000   (  5184 KB)
+[    0.000000]       .init : 0xffff000009080000 - 0xffff000009190000   (  1088 KB)
+[    0.000000]       .data : 0xffff000009190000 - 0xffff0000092ffa00   (  1471 KB)
+[    0.000000]        .bss : 0xffff0000092ffa00 - 0xffff00000937014c   (   450 KB)
+[    0.000000]     fixed   : 0xffff7dfffe7fd000 - 0xffff7dfffec00000   (  4108 KB)
+[    0.000000]     PCI I/O : 0xffff7dfffee00000 - 0xffff7dffffe00000   (    16 MB)
+[    0.000000]     vmemmap : 0xffff7e0000000000 - 0xffff800000000000   (  2048 GB maximum)
+[    0.000000]               0xffff7e0000000000 - 0xffff7e00037a93c0   (    55 MB actual)
+[    0.000000]     memory  : 0xffff800000000000 - 0xffff8000dea4f000   (  3562 MB)
+[    0.000000] SLUB: HWalign=128, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
+[    0.000000] Preemptible hierarchical RCU implementation.
+[    0.000000]  Build-time adjustment of leaf fanout to 64.
+[    0.000000]  RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=4.
+[    0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=64, nr_cpu_ids=4
+[    0.000000] NR_IRQS:64 nr_irqs:64 0
+[    0.000000] GICv3: CPU0: found redistributor 0 region 0:0x0000000009c00000
+[    0.000000] GICv2m: range[mem 0x09bd0000-0x09bd0fff], SPI[544:639]
+[    0.000000] arm_arch_timer: Architected cp15 and mmio timer(s) running at 19.20MHz (virt/virt).
+[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x46d987e47, max_idle_ns: 440795202767 ns
+[    0.000002] sched_clock: 56 bits at 19MHz, resolution 52ns, wraps every 4398046511078ns
+
+[....]
+
+
+Some kernel information:
+
+root@linaro-developer:~# cat /proc/cpuinfo
+processor       : 0
+BogoMIPS        : 38.40
+Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
+CPU implementer : 0x51
+CPU architecture: 8
+CPU variant     : 0x1
+CPU part        : 0x211
+CPU revision    : 2
+
+processor       : 1
+BogoMIPS        : 38.40
+Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
+CPU implementer : 0x51
+CPU architecture: 8
+CPU variant     : 0x1
+CPU part        : 0x211
+CPU revision    : 2
+
+processor       : 2
+BogoMIPS        : 38.40
+Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
+CPU implementer : 0x51
+CPU architecture: 8
+CPU variant     : 0x1
+CPU part        : 0x205
+CPU revision    : 2
+
+processor       : 3
+BogoMIPS        : 38.40
+Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
+CPU implementer : 0x51
+CPU architecture: 8
+CPU variant     : 0x1
+CPU part        : 0x205
+CPU revision    : 2
+
+root@linaro-developer:~# uname -a
+Linux linaro-developer 4.11.3-30039-g5a922a1 #1 SMP PREEMPT Wed Oct 18 10:21:11 CEST 2017 aarch64 GNU/Linux
+
+root@linaro-developer:~# cat /proc/cmdline
+root=/dev/nfs rw nfsroot=192.168.1.2:/db820c/rootfs,v3,tcp rootwait ip=dhcp consoleblank=0 console=tty0 console=ttyMSM0,115200n8 earlyprintk earlycon=msm_serial_dm,0x75b0000 androidboot.bootdevice=624000.ufshc androidboot.verifiedbootstate=orange androidboot.ver0
+
+root@linaro-developer:~# cat /proc/meminfo
+MemTotal:        2776332 kB
+MemFree:         2593696 kB
+MemAvailable:    2561432 kB
+Buffers:               0 kB
+Cached:            94744 kB
+SwapCached:            0 kB
+Active:            43888 kB
+Inactive:          72972 kB
+Active(anon):      22968 kB
+Inactive(anon):    24616 kB
+Active(file):      20920 kB
+Inactive(file):    48356 kB
+Unevictable:           0 kB
+Mlocked:               0 kB
+SwapTotal:             0 kB
+SwapFree:              0 kB
+Dirty:                 0 kB
+Writeback:             0 kB
+AnonPages:         22120 kB
+Mapped:            29284 kB
+Shmem:             25468 kB
+Slab:              32876 kB
+SReclaimable:      12924 kB
+SUnreclaim:        19952 kB
+KernelStack:        2144 kB
+PageTables:          928 kB
+NFS_Unstable:          0 kB
+Bounce:                0 kB
+WritebackTmp:          0 kB
+CommitLimit:     1388164 kB
+Committed_AS:     204192 kB
+VmallocTotal:   135290290112 kB
+VmallocUsed:           0 kB
+VmallocChunk:          0 kB
+AnonHugePages:      2048 kB
+ShmemHugePages:        0 kB
+ShmemPmdMapped:        0 kB
+CmaTotal:         131072 kB
+CmaFree:          130356 kB
+HugePages_Total:       0
+HugePages_Free:        0
+HugePages_Rsvd:        0
+HugePages_Surp:        0
+Hugepagesize:       2048 kB
+
+
+  
+
diff --git a/board/qualcomm/dragonboard820c/u-boot.lds b/board/qualcomm/dragonboard820c/u-boot.lds
new file mode 100644
index 0000000..b84b4ac
--- /dev/null
+++ b/board/qualcomm/dragonboard820c/u-boot.lds
@@ -0,0 +1,106 @@ 
+/*
+ * Override linker script for fastboot-readable images
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * Based on arch/arm/cpu/armv8/u-boot.lds (Just add header)
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+OUTPUT_FORMAT("elf64-littleaarch64", "elf64-littleaarch64", "elf64-littleaarch64")
+OUTPUT_ARCH(aarch64)
+ENTRY(_arm64_header)
+SECTIONS
+{
+	. = 0x00000000;
+
+	. = ALIGN(8);
+	.text :
+	{
+		*(.__image_copy_start)
+		board/qualcomm/dragonboard820c/head.o (.text*)
+		CPUDIR/start.o (.text*)
+		*(.text*)
+	}
+
+	. = ALIGN(8);
+	.rodata : { *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*))) }
+
+	. = ALIGN(8);
+	.data : {
+		*(.data*)
+	}
+
+	. = ALIGN(8);
+
+	. = .;
+
+	. = ALIGN(8);
+	.u_boot_list : {
+		KEEP(*(SORT(.u_boot_list*)));
+	}
+
+	. = ALIGN(8);
+
+	.efi_runtime : {
+                __efi_runtime_start = .;
+		*(efi_runtime_text)
+		*(efi_runtime_data)
+                __efi_runtime_stop = .;
+	}
+
+	.efi_runtime_rel : {
+                __efi_runtime_rel_start = .;
+		*(.relaefi_runtime_text)
+		*(.relaefi_runtime_data)
+                __efi_runtime_rel_stop = .;
+	}
+
+	. = ALIGN(8);
+
+	.image_copy_end :
+	{
+		*(.__image_copy_end)
+	}
+
+	. = ALIGN(8);
+
+	.rel_dyn_start :
+	{
+		*(.__rel_dyn_start)
+	}
+
+	.rela.dyn : {
+		*(.rela*)
+	}
+
+	.rel_dyn_end :
+	{
+		*(.__rel_dyn_end)
+	}
+
+	_end = .;
+
+	. = ALIGN(8);
+
+	.bss_start : {
+		KEEP(*(.__bss_start));
+	}
+
+	.bss : {
+		*(.bss*)
+		 . = ALIGN(8);
+	}
+
+	.bss_end : {
+		KEEP(*(.__bss_end));
+	}
+
+	/DISCARD/ : { *(.dynsym) }
+	/DISCARD/ : { *(.dynstr*) }
+	/DISCARD/ : { *(.dynamic*) }
+	/DISCARD/ : { *(.plt*) }
+	/DISCARD/ : { *(.interp*) }
+	/DISCARD/ : { *(.gnu*) }
+}
diff --git a/configs/dragonboard820c_defconfig b/configs/dragonboard820c_defconfig
new file mode 100644
index 0000000..788ff28
--- /dev/null
+++ b/configs/dragonboard820c_defconfig
@@ -0,0 +1,37 @@ 
+CONFIG_ARM=y
+CONFIG_ARM_SMCCC=y
+CONFIG_ARCH_SNAPDRAGON=y
+CONFIG_TARGET_DRAGONBOARD820C=y
+CONFIG_IDENT_STRING="\nQualcomm-DragonBoard 820C"
+CONFIG_DEFAULT_DEVICE_TREE="dragonboard820c"
+CONFIG_USE_BOOTARGS=y
+# CONFIG_DISPLAY_CPUINFO is not set
+# CONFIG_DISPLAY_BOARDINFO is not set
+CONFIG_BOOTARGS="console=ttyMSM0,115200n8"
+CONFIG_SYS_PROMPT="dragonboard820c => "
+CONFIG_HUSH_PARSER=y
+CONFIG_CMD_BOOTEFI=y
+CONFIG_EFI_LOADER=y
+CONFIG_CMD_BOOTEFI_HELLO=y
+CONFIG_CMD_PXE=y
+CONFIG_CMD_FS_GENERIC=y
+CONFIG_CMD_MEMINFO=y
+CONFIG_CMD_MD5SUM=y
+CONFIG_CMD_CACHE=y
+CONFIG_CMD_PART=y
+CONFIG_CMD_TIMER=y
+CONFIG_CMD_EXT4=y
+CONFIG_CMD_GPT=y
+CONFIG_CMD_MMC=y
+CONFIG_OF_CONTROL=y
+CONFIG_MSM_SERIAL=y
+CONFIG_MMC_SDHCI_MSM=y
+CONFIG_MMC_SDHCI=y
+CONFIG_DM_MMC=y
+CONFIG_CLK=y
+CONFIG_PSCI_RESET=y
+CONFIG_ENV_IS_IN_EXT4=y
+CONFIG_ENV_EXT4_INTERFACE="mmc"
+CONFIG_ENV_EXT4_DEVICE_AND_PART="0:1"
+CONFIG_ENV_EXT4_FILE="/uboot.env"
+
diff --git a/include/configs/dragonboard820c.h b/include/configs/dragonboard820c.h
new file mode 100644
index 0000000..31a6853
--- /dev/null
+++ b/include/configs/dragonboard820c.h
@@ -0,0 +1,72 @@ 
+/*
+ * Board configuration file for Dragonboard 410C
+ *
+ * (C) Copyright 2017 Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __CONFIGS_DRAGONBOARD820C_H
+#define __CONFIGS_DRAGONBOARD820C_H
+
+#include <linux/sizes.h>
+#include <asm/arch/sysmap-apq8096.h>
+
+/* Physical Memory Map */
+#define CONFIG_NR_DRAM_BANKS		2
+
+#define PHYS_SDRAM_SIZE			0xC0000000
+#define PHYS_SDRAM_1			0x80000000
+#define PHYS_SDRAM_1_SIZE		0x60000000
+#define PHYS_SDRAM_2			0x100000000
+#define PHYS_SDRAM_2_SIZE		0x5ea4ffff
+
+#define CONFIG_SYS_SDRAM_BASE		PHYS_SDRAM_1
+#define CONFIG_SYS_TEXT_BASE		0x80080000
+#define CONFIG_SYS_INIT_SP_ADDR		(CONFIG_SYS_SDRAM_BASE + 0x7fff0)
+#define CONFIG_SYS_LOAD_ADDR		(CONFIG_SYS_SDRAM_BASE + 0x80000)
+#define CONFIG_SYS_BOOTM_LEN		0x2000000 
+#define CONFIG_SYS_LDSCRIPT 	"board/qualcomm/dragonboard820c/u-boot.lds"
+
+/* Generic Timer Definitions */
+#define COUNTER_FREQUENCY		19000000
+
+/* Partition table support */
+#define HAVE_BLOCK_DEVICE
+
+/* BOOTP options */
+#define CONFIG_BOOTP_BOOTFILESIZE
+
+#ifndef CONFIG_SPL_BUILD
+#include <config_distro_defaults.h>
+#include <config_distro_bootcmd.h>
+#endif
+
+#define BOOT_TARGET_DEVICES(func) \
+	func(MMC, mmc, 0)
+
+#define CONFIG_EXTRA_ENV_SETTINGS \
+	"loadaddr=0x95000000\0" \
+	"fdt_high=0xffffffffffffffff\0" \
+	"initrd_high=0xffffffffffffffff\0" \
+	"linux_image=uImage\0" \
+	"kernel_addr_r=0x95000000\0"\
+	"fdtfile=apq8096-db820c.dtb\0" \
+	"fdt_addr_r=0x93000000\0"\
+	"ramdisk_addr_r=0x91000000\0"\
+	"scriptaddr=0x90000000\0"\
+	"pxefile_addr_r=0x90100000\0"\
+	BOOTENV
+
+#define CONFIG_EXT4_WRITE
+#define CONFIG_ENV_SIZE			0x4000
+#define CONFIG_ENV_VARS_UBOOT_CONFIG
+
+/* Size of malloc() pool */
+#define CONFIG_SYS_MALLOC_LEN		(CONFIG_ENV_SIZE + SZ_8M)
+
+/* Monitor Command Prompt */
+#define CONFIG_SYS_CBSIZE		512
+#define CONFIG_SYS_MAXARGS		64
+
+#endif