1.首先拿到一个原厂uboot，先编译一下；查找根目录下config目录里自己需要的配置文件，通过在根目录新建如下脚本imx_emmc.sh后，执行 ./imx_emmc.sh后完成编译工作
#!/bin/bash make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- distclean make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- mx6ull_14x14_evk_emmc_defconfig make V=1 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j8
2.把编译得到的uboot.bin烧进板子就可以看到那些部分是支持，那些是不支持的，不支持的就需要我们的移植工作了；既然如此，那就新建一套自己板子的uboot，感受一下一整套流程
2.1：添加配置文件
cd configs
cp mx6ull_14x14_evk_emmc_defconfig mx6ull_alientek_emmc_defconfig
CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/freescale/mx6ull_alientek_emmc/imximage.cfg,MX6ULL_EVK_EMMC_REWORK" CONFIG_ARM=y CONFIG_ARCH_MX6=y CONFIG_TARGET_MX6ULL_ALIENTEK_EMMC=y CONFIG_CMD_GPIO=y
2.2：添加头文件
cd include/configs
cp mx6ullevk.h mx6ull_alientek_emmc.h
记得修改预处理，这个头文件的主要内容就是配置或者裁剪 uboot
2.3：添加板级文件夹
cd board/freescale/
cp mx6ullevk/ -r mx6ull_alientek_emmc
cd mx6ull_alientek_emmc
mv mx6ullevk.c mx6ull_alientek_emmc.c
2.3.1：修改Makefile
# (C) Copyright 2015 Freescale Semiconductor, Inc.
#
# SPDX-License-Identifier: GPL-2.0+
#
obj-y := mx6ull_alientek_emmc.o
extra-$(CONFIG_USE_PLUGIN) := plugin.bin
$(obj)/plugin.bin: $(obj)/plugin.o
$(OBJCOPY) -O binary --gap-fill 0xff $< $@
2.3.2：修改imximage.cfg
PLUGIN board/freescale/mx6ull_alientek_emmc/plugin.bin 0x00907000
2.3.3：修改Kconfig
if TARGET_MX6ULL_ALIENTEK_EMMC config SYS_BOARD default "mx6ull_alientek_emmc" config SYS_VENDOR default "freescale" config SYS_CONFIG_NAME default "mx6ull_alientek_emmc" endif
2.3.4：修改 MAINTAINERS
MX6ULL_ALIENTEK_EMMC BOARD M: Peng Fan <[email protected]> S: Maintained F: board/freescale/mx6ull_alientek_emmc/ F: include/configs/mx6ull_alientek_emmc.h
2.4：修改uboot图形界面配置文件：arch/arm/cpu/armv7/mx6/Kconfig
config TARGET_MX6ULL_ALIENTEK_EMMC bool "Support mx6ull_alientek_emmc" select MX6ULL select DM select DM_THERMAL 。。。。 source "board/freescale/mx6ull_alientek_emmc/Kconfig"
2.5：新建脚本编译新建的uboot
#!/bin/bash make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- distclean make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- mx6ull_alientek_emmc_defconfig make V=1 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j8
2.6：修改lcd驱动，（1）检查gpio引脚；（2）检查lcd信息结构体参数（lcd控制器需要设置的参数）
2.6.1：一般驱动的配置都在xxx.h与.c文件中，在mx6ull_alientek_emmc.c中修改如下
struct display_info_t const displays[] = {{
.bus = MX6UL_LCDIF1_BASE_ADDR,
.addr = 0,
.pixfmt = 24,
.detect = NULL,
.enable = do_enable_parallel_lcd,
.mode = {
.name = "TFT7016",
.xres = 480,
.yres = 272,
.pixclock = 19531,
.left_margin = 140,
.right_margin = 160,
.upper_margin = 20,
.lower_margin = 12,
.hsync_len = 20,
.vsync_len = 3,
.sync = 0,
.vmode = FB_VMODE_NONINTERLACED
} } };
2.6.2：在mx6ull_alientek_emmc.h文件中修改如下：
"panel=TFT7016\0"
2.7：网络驱动修改，看原理图可知，网络信号通过以太网接口，传给phy芯片处理后，再交给ENET1/2控制器处理；imx的ENET_MDIO通过不同的器件地址来访问某个phy芯片；开发板 ENET1 上连接的LAN8720A器件地址为 0X0，所示我们要修改 ENET1 网络驱动；（1）ENET1 复位引脚初始化。（2）LAN8720A 的器件 ID。（3）LAN8720 驱动。 ENET2同理
2.7.1：在mx6ull_alientek_emmc.c中修改地址
#define CONFIG_CMD_NET
#ifdef CONFIG_CMD_NET #define CONFIG_CMD_PING #define CONFIG_CMD_DHCP #define CONFIG_CMD_MII #define CONFIG_FEC_MXC #define CONFIG_MII #define CONFIG_FEC_ENET_DEV 1 #if (CONFIG_FEC_ENET_DEV == 0) #define IMX_FEC_BASE ENET_BASE_ADDR #define CONFIG_FEC_MXC_PHYADDR 0x1 #define CONFIG_FEC_XCV_TYPE RMII #elif (CONFIG_FEC_ENET_DEV == 1) #define IMX_FEC_BASE ENET2_BASE_ADDR #define CONFIG_FEC_MXC_PHYADDR 0x0 #define CONFIG_FEC_XCV_TYPE RMII #endif #define CONFIG_ETHPRIME "FEC" #define CONFIG_PHYLIB #define CONFIG_PHY_SMSC //产品公司名称 #endif
2.7.2：在mx6ull_alientek_emmc.c中删除掉74LV595 的驱动代码；复位引脚修增加如下
#define ENET1_RESET IMX_GPIO_NR(5, 7)
#define ENET2_RESET IMX_GPIO_NR(5, 8)
2.7.3：在mx6ull_alientek_emmc.c中添加复位引脚驱动
static iomux_v3_cfg_t const fec1_pads[] = {
MX6_PAD_GPIO1_IO06__ENET1_MDIO | MUX_PAD_CTRL(MDIO_PAD_CTRL),
MX6_PAD_GPIO1_IO07__ENET1_MDC | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_TX_DATA0__ENET1_TDATA00 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_TX_DATA1__ENET1_TDATA01 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_TX_EN__ENET1_TX_EN | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_TX_CLK__ENET1_REF_CLK1 | MUX_PAD_CTRL(ENET_CLK_PAD_CTRL),
MX6_PAD_ENET1_RX_DATA0__ENET1_RDATA00 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_RX_DATA1__ENET1_RDATA01 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_RX_ER__ENET1_RX_ER | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET1_RX_EN__ENET1_RX_EN | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_SNVS_TAMPER7__GPIO5_IO07 | MUX_PAD_CTRL(NO_PAD_CTRL),
};
static iomux_v3_cfg_t const fec2_pads[] = {
MX6_PAD_GPIO1_IO06__ENET2_MDIO | MUX_PAD_CTRL(MDIO_PAD_CTRL),
MX6_PAD_GPIO1_IO07__ENET2_MDC | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_TX_DATA0__ENET2_TDATA00 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_TX_DATA1__ENET2_TDATA01 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_TX_CLK__ENET2_REF_CLK2 | MUX_PAD_CTRL(ENET_CLK_PAD_CTRL),
MX6_PAD_ENET2_TX_EN__ENET2_TX_EN | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_RX_DATA0__ENET2_RDATA00 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_RX_DATA1__ENET2_RDATA01 | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_RX_EN__ENET2_RX_EN | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_ENET2_RX_ER__ENET2_RX_ER | MUX_PAD_CTRL(ENET_PAD_CTRL),
MX6_PAD_SNVS_TAMPER8__GPIO5_IO08 | MUX_PAD_CTRL(NO_PAD_CTRL),
};
static void setup_iomux_fec(int fec_id)
{
if (fec_id == 0)
{
imx_iomux_v3_setup_multiple_pads(fec1_pads,
ARRAY_SIZE(fec1_pads));
gpio_direction_output(ENET1_RESET, 1);
gpio_set_value(ENET1_RESET, 0);
mdelay(20);
gpio_set_value(ENET1_RESET, 1);
}
else
{
imx_iomux_v3_setup_multiple_pads(fec2_pads,
ARRAY_SIZE(fec2_pads));
gpio_direction_output(ENET2_RESET, 1);
gpio_set_value(ENET2_RESET, 0);
mdelay(20);
gpio_set_value(ENET2_RESET, 1);
}
}
2.7.4：修改 drivers/net/phy/phy.c 文件中的函数 genphy_update_link，添加如下代码段
#ifdef CONFIG_PHY_SMSC
static int lan8720_flag = 0;
int bmcr_reg = 0;
if (lan8720_flag == 0) {
bmcr_reg = phy_read(phydev, MDIO_DEVAD_NONE, MII_BMCR);
phy_write(phydev, MDIO_DEVAD_NONE, MII_BMCR, BMCR_RESET);
while(phy_read(phydev, MDIO_DEVAD_NONE, MII_BMCR) & 0X8000) {
udelay(100);
}
phy_write(phydev, MDIO_DEVAD_NONE, MII_BMCR, bmcr_reg);
lan8720_flag = 1;
}
#endif