参照：http://blog.csdn.net/girlkoo/article/details/45420977
文档参照：
- 《i.MX BSP Porting Guide-2015/12， Rev.0》---------uboot porting steps
- 《E9_TQIMX6Q_V1_20131031.pdf》------------------E9 schematics
- 《E9_User_Manual-V3.1.0》---------------------------Burned methods
BSP版本：L3.14.52.1.1.0
Step1:创建单板board目录，这里选择mx6sabresd作为参考
1 $cp -R board/freescale/mx6sabresd/ board/freescale/mx6q_tqE9/
Step2:创建board配置config文件，这里面设定了dtb文件名称，Stack/Heap大小，DDR大小，zImage装载地址
1 $cp include/configs/mx6sabresd.h include/configs/mx6q_tqE9.h
Step3:<UBOOT_DIR>/configs/目录，创建config选项配置文件, 复制mx6qsabresd_defconfig --> mx6q_tqE9_defconfig, 然后修改为：
1 CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6q_tqE9.cfg,MX6Q" 2 CONFIG_ARM=y 3 CONFIG_TARGET_MX6Q<customer_board>=y 4 CONFIG_SYS_MALLOC_F=y 5 CONFIG_SYS_MALLOC_F_LEN=0x400 6 CONFIG_DM=y 7 CONFIG_DM_THERMAL=y
Step4:文件重命名
1 board/freescale/mx6q_tqE9/mx6sabresd.c --> board/freescale/mx6q_tqE9/mx6q_tqE9.c 2 board/freescale/mx6q_tqE9/mx6qp.cfg --> board/freescale/mx6q_tqE9/mx6q_tqE9.cfg
Step5: 修改board/freescale/mx6q_tqE9目录的Makefile
1 obj-y:= mx6sabresd.o --> obj-y := mx6q_tqE9.o
Step6: 修改Kconfig
- arch/arm/Kconfig
添加：
1 config TARGET_MX6Q_TQE9 2 bool "Support mx6q_tqE9" 3 select CPU_V7 4 source "board/freescale/mx6q_tqE9/Kconfig"
- board/freescale/mx6q_tqE9/Kconfig
修改为：
1 if TARGET_MX6Q_TQE9 2 3 config SYS_BOARD 4 default "mx6q_tqE9" 5 6 config SYS_VENDOR 7 default "freescale" 8 9 config SYS_SOC 10 default "mx6" 11 12 config SYS_CONFIG_NAME 13 default "mx6q_tqE9" 14 15 endif
Step7:创建编译脚本
1 #!/bin/bash 2 export ARCH=arm 3 export CROSS_COMPILE=/opt/Embedsky/gcc-4.6.2-glibc-2.13-linaro-multilib-2011.12/tq-linaro-toolchain/bin/arm-fsl-linux-gnueabi- 4 make distclean; 5 make mx6q_tqE9_defconfig 6 make
Step8:参照@girlkoo：
1. 定制DDR，目录为board/freescale/mx6q_tqE9/mx6q_tqE9.cfg
1 DATA 4, 0x020e0798, 0x000C0000 2 DATA 4, 0x020e0758, 0x00000000 3 DATA 4, 0x020e0588, 0x00000030 4 DATA 4, 0x020e0594, 0x00000030 5 DATA 4, 0x020e056c, 0x00000030 6 DATA 4, 0x020e0578, 0x00000030 7 DATA 4, 0x020e074c, 0x00000030 8 DATA 4, 0x020e057c, 0x00000030 9 DATA 4, 0x020e058c, 0x00000000 10 DATA 4, 0x020e059c, 0x00000030 11 DATA 4, 0x020e05a0, 0x00000030 12 DATA 4, 0x020e078c, 0x00000030 13 DATA 4, 0x020e0750, 0x00020000 14 DATA 4, 0x020e05a8, 0x00000018 15 DATA 4, 0x020e05b0, 0x00000018 16 DATA 4, 0x020e0524, 0x00000018 17 DATA 4, 0x020e051c, 0x00000018 18 DATA 4, 0x020e0518, 0x00000018 19 DATA 4, 0x020e050c, 0x00000018 20 DATA 4, 0x020e05b8, 0x00000018 21 DATA 4, 0x020e05c0, 0x00000018 22 DATA 4, 0x020e0774, 0x00020000 23 DATA 4, 0x020e0784, 0x00000018 24 DATA 4, 0x020e0788, 0x00000018 25 DATA 4, 0x020e0794, 0x00000018 26 DATA 4, 0x020e079c, 0x00000018 27 DATA 4, 0x020e07a0, 0x00000018 28 DATA 4, 0x020e07a4, 0x00000018 29 DATA 4, 0x020e07a8, 0x00000018 30 DATA 4, 0x020e0748, 0x00000018 31 DATA 4, 0x020e05ac, 0x00000018 32 DATA 4, 0x020e05b4, 0x00000018 33 DATA 4, 0x020e0528, 0x00000018 34 DATA 4, 0x020e0520, 0x00000018 35 DATA 4, 0x020e0514, 0x00000018 36 DATA 4, 0x020e0510, 0x00000018 37 DATA 4, 0x020e05bc, 0x00000018 38 DATA 4, 0x020e05c4, 0x00000018 39 DATA 4, 0x021b0800, 0xa1390003 40 DATA 4, 0x021b080c, 0x001F001F 41 DATA 4, 0x021b0810, 0x001F001F 42 DATA 4, 0x021b480c, 0x001F001F 43 DATA 4, 0x021b4810, 0x001F001F 44 DATA 4, 0x021b083c, 0x43270338 45 DATA 4, 0x021b0840, 0x03200314 46 DATA 4, 0x021b483c, 0x431A032F 47 DATA 4, 0x021b4840, 0x03200263 48 DATA 4, 0x021b0848, 0x4B434748 49 DATA 4, 0x021b4848, 0x4445404C 50 DATA 4, 0x021b0850, 0x38444542 51 DATA 4, 0x021b4850, 0x4935493A 52 DATA 4, 0x021b081c, 0x33333333 53 DATA 4, 0x021b0820, 0x33333333 54 DATA 4, 0x021b0824, 0x33333333 55 DATA 4, 0x021b0828, 0x33333333 56 DATA 4, 0x021b481c, 0x33333333 57 DATA 4, 0x021b4820, 0x33333333 58 DATA 4, 0x021b4824, 0x33333333 59 DATA 4, 0x021b4828, 0x33333333 60 DATA 4, 0x021b08b8, 0x00000800 61 DATA 4, 0x021b48b8, 0x00000800 62 DATA 4, 0x021b0004, 0x00020036 63 DATA 4, 0x021b0008, 0x09444040 64 DATA 4, 0x021b000c, 0x8A8F7955 65 DATA 4, 0x021b0010, 0xFF328F64 66 DATA 4, 0x021b0014, 0x01FF00DB 67 DATA 4, 0x021b0018, 0x00001740 68 DATA 4, 0x021b001c, 0x00008000 69 DATA 4, 0x021b002c, 0x000026d2 70 DATA 4, 0x021b0030, 0x008F1023 71 DATA 4, 0x021b0040, 0x00000047 72 DATA 4, 0x021b0000, 0x841A0000 73 DATA 4, 0x021b001c, 0x04088032 74 DATA 4, 0x021b001c, 0x00008033 75 DATA 4, 0x021b001c, 0x00048031 76 DATA 4, 0x021b001c, 0x09408030 77 DATA 4, 0x021b001c, 0x04008040 78 DATA 4, 0x021b0020, 0x00005800 79 DATA 4, 0x021b0818, 0x00011117 80 DATA 4, 0x021b4818, 0x00011117 81 DATA 4, 0x021b0004, 0x00025576 82 DATA 4, 0x021b0404, 0x00011006 83 DATA 4, 0x021b001c, 0x00000000 84 85 /* set the default clock gate to save power */ 86 DATA 4, 0x020c4068, 0x00C03F3F 87 DATA 4, 0x020c406c, 0x0030FC03 88 DATA 4, 0x020c4070, 0x0FFFC000 89 DATA 4, 0x020c4074, 0x3FF00000 90 DATA 4, 0x020c4078, 0x00FFF300 91 DATA 4, 0x020c407c, 0x0F0000F3 92 DATA 4, 0x020c4080, 0x000003FF 93 94 /* enable AXI cache for VDOA/VPU/IPU */ 95 DATA 4, 0x020e0010, 0xF00000CF 96 /* set IPU AXI-id0 Qos=0xf(bypass) AXI-id1 Qos=0x7 */ 97 DATA 4, 0x020e0018, 0x007F007F 98 DATA 4, 0x020e001c, 0x007F007F
2. 定制board端子，board/freescale/mx6q_tqE9/mx6q_tqE9.c
<1>.修改串口如下：
1 iomux_v3_cfg_t const uart1_pads[] = { 2 // MX6_PAD_CSI0_DAT10__UART1_TXD | MUX_PAD_CTRL(UART_PAD_CTRL), 3 // MX6_PAD_CSI0_DAT11__UART1_RXD | MUX_PAD_CTRL(UART_PAD_CTRL), 4 MX6_PAD_SD3_DAT7__UART1_TX_DATA | MUX_PAD_CTRL(UART_PAD_CTRL), 5 MX6_PAD_SD3_DAT6__UART1_RX_DATA | MUX_PAD_CTRL(UART_PAD_CTRL), 6 };
<2>.修改SD卡端子：
1 iomux_v3_cfg_t const usdhc2_pads[] = { 2 MX6_PAD_SD2_CLK__USDHC2_CLK | MUX_PAD_CTRL(USDHC_PAD_CTRL), 3 MX6_PAD_SD2_CMD__USDHC2_CMD | MUX_PAD_CTRL(USDHC_PAD_CTRL), 4 MX6_PAD_SD2_DAT0__USDHC2_DAT0 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 5 MX6_PAD_SD2_DAT1__USDHC2_DAT1 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 6 MX6_PAD_SD2_DAT2__USDHC2_DAT2 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 7 MX6_PAD_SD2_DAT3__USDHC2_DAT3 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 8 // MX6_PAD_NANDF_D4__USDHC2_DAT4 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 9 // MX6_PAD_NANDF_D5__USDHC2_DAT5 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 10 // MX6_PAD_NANDF_D6__USDHC2_DAT6 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 11 // MX6_PAD_NANDF_D7__USDHC2_DAT7 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 12 // MX6_PAD_NANDF_D2__GPIO_2_2 | MUX_PAD_CTRL(NO_PAD_CTRL), /* CD */ 13 }; 14 15 iomux_v3_cfg_t const usdhc3_pads[] = { 16 MX6_PAD_SD3_CLK__USDHC3_CLK | MUX_PAD_CTRL(USDHC_PAD_CTRL), 17 MX6_PAD_SD3_CMD__USDHC3_CMD | MUX_PAD_CTRL(USDHC_PAD_CTRL), 18 MX6_PAD_SD3_DAT0__USDHC3_DAT0 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 19 MX6_PAD_SD3_DAT1__USDHC3_DAT1 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 20 MX6_PAD_SD3_DAT2__USDHC3_DAT2 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 21 MX6_PAD_SD3_DAT3__USDHC3_DAT3 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 22 MX6_PAD_SD3_DAT4__USDHC3_DAT4 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 23 MX6_PAD_SD3_DAT5__USDHC3_DAT5 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 24 // MX6_PAD_SD3_DAT6__USDHC3_DAT6 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 25 // MX6_PAD_SD3_DAT7__USDHC3_DAT7 | MUX_PAD_CTRL(USDHC_PAD_CTRL), 26 MX6_PAD_NANDF_D0__GPIO_2_0 | MUX_PAD_CTRL(NO_PAD_CTRL), /* CD */ 27 };
<3>.定制Card Detect端子，否则SD卡插入会检测不到
1 #define USDHC2_CD_GPIO IMX_GPIO_NR(1, 4)
Step9: 编译
1 ./build_uboot.sh
Step10: 烧写，下载：
烧写SD卡：
sudo dd if=u-boot.imx of=/dev/sdc bs=512 seek=2
sync
更改E9为SD卡启动：
Jumper为1~7: 1 0 0 0 0 0 1.
输出log:
1 U-Boot 2015.04-imx_v2015.04_3.14.52_1.1.0_ga+g6cf684a (Oct 05 2016 - 23:57:59) 2 3 CPU: Freescale i.MX6Q rev1.2 at 792 MHz 4 CPU: Temperature -140462619 C 5 Reset cause: POR 6 Board: MX6-TQE9 7 I2C: ready 8 DRAM: 2 GiB 9 Can't find PMIC:PFUZE100 10 initcall sequence 8ff93570 failed at call 178036e8 (err=-19) 11 ### ERROR ### Please RESET the board ###
Issue1:
这里遇到一个问题就是串口管脚的修改，E9的管脚UART1_TXD(SD3_DAT7)和UART1_RXD(SD3_DAT6)，所以需要修改，而原有在sabresd板子中配置为MX6_PAD_CSI0_DAT10__UART1_TX_DATA和MX6_PAD_CSI0_DAT11__UART1_RX_DATA，使用grep并找不到定义，所以也就找不到此版本下SD3_DAT7和SD3_DAT6应该怎么表示，刚开始修改不对，uboot打印一直不出现。
后来通过mx6q_tqE9.c包含头文件找到arch/arm/include/asm/arch-mx6/mx6q_pins.h:851:
1 MX6_PAD_DECL(SD3_DAT7__UART1_TX_DATA, 0x0690, 0x02A8, 1, 0x0000, 0, 0)
而在arch/arm/include/asm/arch-mx6/mx6-pins.h中有这样定义：
1 #elif defined(CONFIG_MX6Q) 2 enum { 3 #define MX6_PAD_DECL(name, pco, mc, mm, sio, si, pc) 4 MX6_PAD_DECLARE(MX6_PAD_,name, pco, mc, mm, sio, si, pc), 5 #include "mx6q_pins.h" 6 };
进而有同样在arch/arm/include/asm/arch-mx6/mx6-pins.h：
1 #define MX6_PAD_DECLARE(prefix, name, pco, mc, mm, sio, si, pc) 2 prefix##name = IOMUX_PAD(pco, mc, mm, sio, si, pc)
这样也就有了串口MX6_PAD_SD3_DAT7__UART1_TX_DATA的定义。
Issue2:
从上述的log中可以看出，虽然有打印，但是uboot并未被正常执行，提示Can't find PMIC:PFUZE100错误，于是参照fsl社区的答疑，https://community.nxp.com/message/651335， 按照FAE说的加#undef CONFIG_LDO_BYPASS_CHECK并没有解决问题，看上去pmic_probe函数仍然被执行了；于是按照用户的答案，disable pmic代码，/drivers/power/power_i2c.c 屏蔽pmic_probe函数内容，于是通过了，最终输出log如下：
1 U-Boot 2015.04-imx_v2015.04_3.14.52_1.1.0_ga+g6cf684a (Oct 06 2016 - 11:55:51) 2 3 CPU: Freescale i.MX6Q rev1.2 at 792 MHz 4 CPU: Temperature -140462630 C 5 Reset cause: POR 6 Board: MX6-TQE9 7 I2C: ready 8 DRAM: 2 GiB 9 PMIC: PFUZE100 ID=0x8ffa132f 10 Not supported, id=12 11 MMC: FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 2 12 *** Warning - bad CRC, using default environment 13 14 No panel detected: default to Hannstar-XGA 15 Display: Hannstar-XGA (1024x768) 16 In: serial 17 Out: serial 18 Err: serial 19 switch to partitions #0, OK 20 mmc0 is current device 21 Net: Phy 1 not found 22 PHY reset timed out 23 FEC [PRIME] 24 Error: FEC address not set. 25 26 Normal Boot 27 Hit any key to stop autoboot: 0 28 switch to partitions #0, OK 29 mmc0 is current device 30 ** No partition table - mmc 0 ** 31 ** No partition table - mmc 0 ** 32 Booting from net ... 33 *** ERROR: `ethaddr' not set 34 *** ERROR: `ethaddr' not set 35 Bad Linux ARM zImage magic! 36 =>
这样看上去uboot已经移植成功了！以前没有做过类似的事情，还是费了不少周折，后面抽时间看看源码。
推荐博文：
1.uboot启动过程完全分析(uboot启动启动2个阶段分析)
http://blog.csdn.net/hanchaoman/article/details/9282947
2.uboot的两个启动过程和第二阶段的board_init_f/board_init_r
http://tscsh.blog.163.com/blog/static/200320103201312645149965/
问题：
1. SD卡格式化
mkfs.ext4 /dev/sdc
2. 格式化完后分区
3. 以上的编译使用的工具链还是较老的工具链，E9光盘安装，并没有更新
4. 为什么uboot启动要分为两个阶段？
个人理解，可以试想一下，如果只有1个阶段，片内固化ROM代码将uboot代码直接拷贝到片内RAM然后执行，uboot大小可能超过片内RAM，直接拷贝到DDR，又会有DDR还没有初始化，也就是不可以这么做。所以只可以在uboot分为两段启动，第一段运行在片内RAM，初始化DDR，第二段运行在DDR中，搬运内核，跳转。