ZYNQ FLASH+EMMC手动移植LINUX启动

前言

虽可使用Petalinux进行移植，简单方便，但为了更清楚明白的了解整个流程，还是尝试了一波手动移植。

参考资料

ZYNQ Linux 移植：包含petalinux移植和手动移植debian9

ZYNQ #5 - 从vivado工程开始，从emmc启动Linux_里先森-CSDN博客

流程

对于手动移植，所需的文件为：

BOOT.bin(FSBL+fpga_bit文件+u_boot.elf)、uImage、devicetree.dtb、uEnv.txt、文件系统

文件放置位置说明：

FLASH：BOOT.bin(FSBL+fpga_bit文件+u_boot.elf)

EMMC：

第一个分区放置：uImage、devicetree.dtb、uEnv.txt

第二个分区放置：文件系统

启动流程为：板子设置为QSPI启动模式，FSBL执行调u-boot执行，u-boot根据uEnv.txt调EMMC分区1中的内核执行，内核最后跳到分区二中的文件系统。

FSBL、bit文件、uImage、文件系统都可复用SD卡移植模式下的内容：参考参考资料第一个链接。

本文章主要讲述的重点在于：u-boot、设备树、uEnv.txt的更改部分

板子主要信息说明：板子芯片：ZYNQ7035，板子的调试打印串口为PS0，板子上有SD卡(SD0)、EMMC(SD1)，板子上有FLASH。其他外设不赘述。

u-boot移植说明：

1.下载u-boot源码：git clone [https://github.com/Xilinx/u-boot-xlnx.git](https://github.com/Xilinx/u-boot-xlnx.git)

NOTE：u-boot xilinx-v2018.3版本的zynq-common.h跟xilinx-v2018.1版本的不一样，这里检出v2018.1版本使用。

主要是CONFIG_EXTRA_ENV_SETTINGS 环境变量不一致。

默认的如下所示：

/* Default environment */

#ifndef CONFIG_EXTRA_ENV_SETTINGS

#define CONFIG_EXTRA_ENV_SETTINGS	\

	"ethaddr=00:0a:35:00:01:22\0"	\

	"kernel_image=uImage\0"	\

	"kernel_load_address=0x2080000\0" \

	"ramdisk_image=uramdisk.image.gz\0"	\

	"ramdisk_load_address=0x4000000\0"	\

	"devicetree_image=devicetree.dtb\0"	\

	"devicetree_load_address=0x2000000\0"	\

	"bitstream_image=system.bit.bin\0"	\

	"boot_image=BOOT.bin\0"	\

	"loadbit_addr=0x100000\0"	\

	"loadbootenv_addr=0x2000000\0" \

	"kernel_size=0x500000\0"	\

	"devicetree_size=0x20000\0"	\

	"ramdisk_size=0x5E0000\0"	\

	"boot_size=0xF00000\0"	\

	"fdt_high=0x20000000\0"	\

	"initrd_high=0x20000000\0"	\

	"bootenv=uEnv.txt\0" \

	"loadbootenv=load mmc 0 ${loadbootenv_addr} ${bootenv}\0" \

	"importbootenv=echo Importing environment from SD ...; " \

		"env import -t ${loadbootenv_addr} $filesize\0" \

	"sd_uEnvtxt_existence_test=test -e mmc 0 /uEnv.txt\0" \

	"preboot=if test $modeboot = sdboot && env run sd_uEnvtxt_existence_test; " \

			"then if env run loadbootenv; " \

				"then env run importbootenv; " \

			"fi; " \

		"fi; \0" \

	"mmc_loadbit=echo Loading bitstream from SD/MMC/eMMC to RAM.. && " \

		"mmcinfo && " \

		"load mmc 0 ${loadbit_addr} ${bitstream_image} && " \

		"fpga load 0 ${loadbit_addr} ${filesize}\0" \

	"norboot=echo Copying Linux from NOR flash to RAM... && " \

		"cp.b 0xE2100000 ${kernel_load_address} ${kernel_size} && " \

		"cp.b 0xE2600000 ${devicetree_load_address} ${devicetree_size} && " \

		"echo Copying ramdisk... && " \

		"cp.b 0xE2620000 ${ramdisk_load_address} ${ramdisk_size} && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"qspiboot=echo Copying Linux from QSPI flash to RAM... && " \

		"sf probe 0 0 0 && " \

		"sf read ${kernel_load_address} 0x100000 ${kernel_size} && " \

		"sf read ${devicetree_load_address} 0x600000 ${devicetree_size} && " \

		"echo Copying ramdisk... && " \

		"sf read ${ramdisk_load_address} 0x620000 ${ramdisk_size} && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"uenvboot=" \

		"if run loadbootenv; then " \

			"echo Loaded environment from ${bootenv}; " \

			"run importbootenv; " \

		"fi; " \

		"if test -n $uenvcmd; then " \

			"echo Running uenvcmd ...; " \

			"run uenvcmd; " \

		"fi\0" \

	"sdboot=if mmcinfo; then " \

			"run uenvboot; " \

			"echo Copying Linux from SD to RAM... && " \

			"load mmc 0 ${kernel_load_address} ${kernel_image} && " \

			"load mmc 0 ${devicetree_load_address} ${devicetree_image} && " \

			"load mmc 0 ${ramdisk_load_address} ${ramdisk_image} && " \

			"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}; " \

		"fi\0" \

	"usbboot=if usb start; then " \

			"run uenvboot; " \

			"echo Copying Linux from USB to RAM... && " \

			"load usb 0 ${kernel_load_address} ${kernel_image} && " \

			"load usb 0 ${devicetree_load_address} ${devicetree_image} && " \

			"load usb 0 ${ramdisk_load_address} ${ramdisk_image} && " \

			"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}; " \

		"fi\0" \

	"nandboot=echo Copying Linux from NAND flash to RAM... && " \

		"nand read ${kernel_load_address} 0x100000 ${kernel_size} && " \

		"nand read ${devicetree_load_address} 0x600000 ${devicetree_size} && " \

		"echo Copying ramdisk... && " \

		"nand read ${ramdisk_load_address} 0x620000 ${ramdisk_size} && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"jtagboot=echo TFTPing Linux to RAM... && " \

		"tftpboot ${kernel_load_address} ${kernel_image} && " \

		"tftpboot ${devicetree_load_address} ${devicetree_image} && " \

		"tftpboot ${ramdisk_load_address} ${ramdisk_image} && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"rsa_norboot=echo Copying Image from NOR flash to RAM... && " \

		"cp.b 0xE2100000 0x100000 ${boot_size} && " \

		"zynqrsa 0x100000 && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"rsa_nandboot=echo Copying Image from NAND flash to RAM... && " \

		"nand read 0x100000 0x0 ${boot_size} && " \

		"zynqrsa 0x100000 && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"rsa_qspiboot=echo Copying Image from QSPI flash to RAM... && " \

		"sf probe 0 0 0 && " \

		"sf read 0x100000 0x0 ${boot_size} && " \

		"zynqrsa 0x100000 && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"rsa_sdboot=echo Copying Image from SD to RAM... && " \

		"load mmc 0 0x100000 ${boot_image} && " \

		"zynqrsa 0x100000 && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

	"rsa_jtagboot=echo TFTPing Image to RAM... && " \

		"tftpboot 0x100000 ${boot_image} && " \

		"zynqrsa 0x100000 && " \

		"bootm ${kernel_load_address} ${ramdisk_load_address} ${devicetree_load_address}\0" \

		DFU_ALT_INFO \

		BOOTENV

#endif

可以看到其上定义了一堆的东西及不同的启动指令。

不同的启动指令由#define CONFIG_BOOTCOMMAND指定。

这里想FLASH+EMMC启动，则可以选择sdboot，同时因为EMMC是SD1，所以上述的文件需要进行更改：更改uEnv.txt的存储位置为mmc 1；去掉sdboot中的ramdisk，及存储kernel、设备树位置为mmc 1；修改bootm参数。

	"loadbootenv=load mmc 1 ${loadbootenv_addr} ${bootenv}\0" \

	"importbootenv=echo Importing environment from SD ...; " \

		"env import -t ${loadbootenv_addr} $filesize\0" \

	"sd_uEnvtxt_existence_test=test -e mmc 1 /uEnv.txt\0" \

"sdboot=if mmcinfo; then " \

			"run uenvboot; " \

			"echo Copying Linux from hahahah SD to RAM... && " \

			"load mmc 1 ${kernel_load_address} ${kernel_image} && " \

			"load mmc 1 ${devicetree_load_address} ${devicetree_image} && " \

			"bootm ${kernel_load_address} - ${devicetree_load_address}; " \

		"fi\0" \

上述命令的执行逻辑为：u-boot启动后，执行sdboot指令：

（1）装载uEnv.txt文件并运行；

（2）装载内核、设备树；

（3）运行；

2.由于是自己做的板子，则可以基于类似的板子defconfig进行修改适配u-boot：这里使用zynq_zed_defconfig文件：

（1）增加传统镜像文件支持：CONFIG_IMAGE_FORMAT_LEGACY=y

（2）因为已经知道是从EMMC启动相关文件，则可直接指定：CONFIG_BOOTCOMMAND="mmc dev 1;run sdboot"

mmc dev 1是为了避免u-boot死锁bug(移植petalinux中u-boot存在，为官方bug，这里加上，不知道有没有用)；sdboot会直接调用执行zynq-common.h中的对应选项。

（3）因为板子上串口使用的是PS0，修改：CONFIG_DEBUG_UART_BASE=0xe0000000（地址可在设备树中查看）

文件参考：

CONFIG_ARM=y

CONFIG_ARCH_ZYNQ=y

CONFIG_SYS_TEXT_BASE=0x4000000

CONFIG_SPL_STACK_R_ADDR=0x200000

CONFIG_DEFAULT_DEVICE_TREE="zynq-zed"

CONFIG_DEBUG_UART=y

CONFIG_DISTRO_DEFAULTS=y

CONFIG_IMAGE_FORMAT_LEGACY=y

CONFIG_FIT=y

CONFIG_FIT_SIGNATURE=y

CONFIG_FIT_VERBOSE=y

CONFIG_BOOTCOMMAND="mmc dev 1;run sdboot"

# CONFIG_DISPLAY_CPUINFO is not set

CONFIG_SPL=y

CONFIG_SPL_STACK_R=y

CONFIG_SPL_OS_BOOT=y

CONFIG_SYS_PROMPT="Zynq> "

CONFIG_CMD_THOR_DOWNLOAD=y

CONFIG_CMD_DFU=y

# CONFIG_CMD_FLASH is not set

CONFIG_CMD_FPGA_LOADBP=y

CONFIG_CMD_FPGA_LOADFS=y

CONFIG_CMD_FPGA_LOADMK=y

CONFIG_CMD_FPGA_LOADP=y

CONFIG_CMD_GPIO=y

CONFIG_CMD_MMC=y

CONFIG_CMD_SF=y

CONFIG_CMD_USB=y

# CONFIG_CMD_SETEXPR is not set

CONFIG_CMD_TFTPPUT=y

CONFIG_CMD_CACHE=y

CONFIG_CMD_EXT4_WRITE=y

CONFIG_OF_EMBED=y

CONFIG_ENV_IS_IN_SPI_FLASH=y

CONFIG_NET_RANDOM_ETHADDR=y

CONFIG_SPL_DM_SEQ_ALIAS=y

CONFIG_DFU_MMC=y

CONFIG_DFU_RAM=y

CONFIG_FPGA_XILINX=y

CONFIG_DM_GPIO=y

CONFIG_MMC_SDHCI=y

CONFIG_MMC_SDHCI_ZYNQ=y

CONFIG_SPI_FLASH=y

CONFIG_SPI_FLASH_BAR=y

CONFIG_SF_DUAL_FLASH=y

CONFIG_SPI_FLASH_SPANSION=y

CONFIG_SPI_FLASH_STMICRO=y

CONFIG_SPI_FLASH_WINBOND=y

CONFIG_PHY_MARVELL=y

CONFIG_PHY_REALTEK=y

CONFIG_PHY_XILINX=y

CONFIG_ZYNQ_GEM=y

CONFIG_DEBUG_UART_ZYNQ=y

CONFIG_DEBUG_UART_BASE=0xe0000000

CONFIG_DEBUG_UART_CLOCK=50000000

CONFIG_ZYNQ_SERIAL=y

CONFIG_ZYNQ_QSPI=y

CONFIG_USB=y

CONFIG_USB_EHCI_HCD=y

CONFIG_USB_ULPI_VIEWPORT=y

CONFIG_USB_ULPI=y

CONFIG_USB_STORAGE=y

CONFIG_USB_GADGET=y

CONFIG_USB_GADGET_MANUFACTURER="Xilinx"

CONFIG_USB_GADGET_VENDOR_NUM=0x03fd

CONFIG_USB_GADGET_PRODUCT_NUM=0x0300

CONFIG_CI_UDC=y

CONFIG_USB_GADGET_DOWNLOAD=y

3.修改u-boot的设备树：实际上u-boot也带了设备树，这里需要进行修改：

（1）修改uart为uart0；

（2）修改SD为mmc1；

（3）去除QSPI中的分区表；

文件参考：

/*

 * Xilinx ZED board DTS

 *

 *  Copyright (C) 2011 - 2015 Xilinx

 *  Copyright (C) 2012 National Instruments Corp.

 *

 * SPDX-License-Identifier:	GPL-2.0+

 */

/dts-v1/;

#include "zynq-7000.dtsi"

/ {

	model = "Zynq Zed Development Board";

	compatible = "xlnx,zynq-zed", "xlnx,zynq-7000";

	aliases {

		ethernet0 = &gem0;

		serial0 = &uart0;

		spi0 = &qspi;

		mmc1 = &sdhci1;

	};

	memory@0 {

		device_type = "memory";

		reg = <0x0 0x20000000>;

	};

	chosen {

		bootargs = "";

		stdout-path = "serial0:115200n8";

	};

	usb_phy0: phy0@e0002000 {

		compatible = "ulpi-phy";

		#phy-cells = <0>;

		reg = <0xe0002000 0x1000>;

		view-port = <0x0170>;

		drv-vbus;

	};

};

&clkc {

	ps-clk-frequency = <33333333>;

};

&gem0 {

	status = "okay";

	phy-mode = "rgmii-id";

	phy-handle = <&ethernet_phy>;

	ethernet_phy: ethernet-phy@0 {

		reg = <0>;

		device_type = "ethernet-phy";

	};

};

&qspi {

	u-boot,dm-pre-reloc;

	status = "okay";

	is-dual = <0>;

	num-cs = <1>;

	flash@0 {

		compatible = "n25q128a11";

		reg = <0x0>;

		spi-tx-bus-width = <1>;

		spi-rx-bus-width = <4>;

		spi-max-frequency = <50000000>;

		#address-cells = <1>;

		#size-cells = <1>;

	};

};

&sdhci1 {

	u-boot,dm-pre-reloc;

	status = "okay";

};

&uart0 {

	u-boot,dm-pre-reloc;

	status = "okay";

};

&usb0 {

	status = "okay";

	dr_mode = "host";

	usb-phy = <&usb_phy0>;

};

编译u-boot：

清除中间编译：

make distclean

使用配置文件：

make CROSS_COMPILE=arm-linux-gnueabihf- zynq_zed_defconfig

通过下述指令可在界面中uboot进行进一步修改配置：改defconfig文件也可以，暂时默认即可

make CROSS_COMPILE=arm-linux-gnueabihf- menuconfig

工具编译：

make CROSS_COMPILE=arm-linux-gnueabihf- tools

编译u-boot：

make CROSS_COMPILE=arm-linux-gnueabihf-

修改总设备树的boottags：console=ttyPS0,115200n8 root=/dev/mmcblk1p2 rw noinitrd rootfstype=ext4 rootwait
修改uEnv.txt为：mmc 0修改为mmc 1；root=/dev/mmcblk1p2

bootargs=console=ttyPS0,115200 root=/dev/mmcblk1p2 rw earlyprintk rootfstype=ext4 rootwait

load_image=fatload mmc 1 ${kernel_load_address} ${kernel_image} && fatload mmc 1 ${devicetree_load_address} ${devicetree_image}

uenvcmd=echo Copying Linux from SD to RAM... && mmcinfo &&  run load_image && bootm ${kernel_load_address} - ${devicetree_load_address}

组装BOOT.bin，不赘述。
烧录BOOT.bin到FLASH，对EMMC进行分区，EMMC分区一中放置uImage、devicetree.dtb、uEnv.txt,EMMC分区二中放置文件系统即可。
启动。

U-Boot 2018.01-dirty (Jul 26 2021 - 20:05:00 +0800)

Model: Zynq Zed Development Board

Board: Xilinx Zynq

Silicon: v3.1

DRAM:  ECC disabled 512 MiB

MMC:   sdhci_transfer_data: Error detected in status(0x208000)!

sdhci@e0101000: 1 (eMMC)

SF: Detected s25fl128s_64k with page size 256 Bytes, erase size 64 KiB, total 16 MiB

*** Warning - bad CRC, using default environment

In:    serial@e0000000

Out:   serial@e0000000

Err:   serial@e0000000

Net:   ZYNQ GEM: e000b000, phyaddr 0, interface rgmii-id

eth0: ethernet@e000b000

Hit any key to stop autoboot:  0

sdhci_transfer_data: Error detected in status(0x208000)!

switch to partitions #0, OK

mmc1(part 0) is current device

Device: sdhci@e0101000

Manufacturer ID: 13

OEM: 14e

Name: Q2J55

Tran Speed: 25000000

Rd Block Len: 512

MMC version 5.0

High Capacity: Yes

Capacity: 7.1 GiB

Bus Width: 4-bit

Erase Group Size: 512 KiB

HC WP Group Size: 8 MiB

User Capacity: 7.1 GiB WRREL

Boot Capacity: 16 MiB ENH

RPMB Capacity: 4 MiB ENH

reading uEnv.txt

356 bytes read in 11 ms (31.3 KiB/s)

Loaded environment from uEnv.txt

Importing environment from SD ...

Running uenvcmd ...

Copying Linux from SD to RAM...

Device: sdhci@e0101000

Manufacturer ID: 13

OEM: 14e

Name: Q2J55

Tran Speed: 25000000

Rd Block Len: 512

MMC version 5.0

High Capacity: Yes

Capacity: 7.1 GiB

Bus Width: 4-bit

Erase Group Size: 512 KiB

HC WP Group Size: 8 MiB

User Capacity: 7.1 GiB WRREL

Boot Capacity: 16 MiB ENH

RPMB Capacity: 4 MiB ENH

reading uImage

4001616 bytes read in 377 ms (10.1 MiB/s)

reading devicetree.dtb

17052 bytes read in 18 ms (924.8 KiB/s)

## Booting kernel from Legacy Image at 02080000 ...

   Image Name:   Linux-4.14.0-xilinx

   Image Type:   ARM Linux Kernel Image (uncompressed)

   Data Size:    4001552 Bytes = 3.8 MiB

   Load Address: 00008000

   Entry Point:  00008000

   Verifying Checksum ... OK

## Flattened Device Tree blob at 02000000

   Booting using the fdt blob at 0x2000000

   Loading Kernel Image ... OK

   Loading Device Tree to 1eb12000, end 1eb1929b ... OK

以上。

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