3. U-boot Porting¶

3.1. U-boot Hardware Environment¶

The peripheral components on the cv184x development board include DDR, eMMC, SPI NAND

Flash, and SPI NOR Flash, for all models

See CV184x_Hardware Design User Guide_V1.0

3.2. Pin Configuration (Pinmux)¶

For different EVBs and peripheral devices, initialization can be configured in cvi_board_init.c.

$ cat build/boards/cv184x/cv1842hp_wevb_0014a_spinor/u-boot/cvi_board_init.c
int cvi_board_init(void)
{
     PINMUX_CONFIG(PAD_MIPIRX1P, IIC1_SDA);
     PINMUX_CONFIG(PAD_MIPIRX0N, IIC1_SCL);
     PINMUX_CONFIG(PAD_MIPIRX1N, XGPIOC_8);
     PINMUX_CONFIG(PAD_MIPIRX0P, CAM_MCLK0);
     return 0;
}

3.3. Build U-Boot¶

Build U-Boot as follows:

$ source build/envsetup_soc.sh

$ defconfig cv1842hp_wevb_0014a_spinor

$ clean_uboot && build_uboot
[TARGET] u-boot-dts
......
[TARGET] u-boot-build
......

Obtain fip_spl.bin and fip.bin (containing bootloader + U-Boot)

$ ls install/soc_cv1842hp_wevb_0014a_spinor/fip.bin
install/soc_cv1842hp_wevb_0014a_spinor/fip.bin
$ ls install/soc_cv1842hp_wevb_0014a_spinor/fip_spl.bin
install/soc_cv1842hp_wevb_0014a_spinor/fip_spl.bin

U-boot Settings

Default U-Boot configuration for the EVB

$ cat build/boards/cv184x/cv1842hp_wevb_0014a_spinor/u-boot/cvitek_cv1842hp_wevb_0014a_spinor_defconfig
 CONFIG_ARM=y
 CONFIG_SYS_MALLOC_F_LEN=0x100000
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_DEFAULT_DEVICE_TREE="cv184x_asic"
 CONFIG_IDENT_STRING=" cvitek_cv184x"
...

There are two ways to modify a defconfig file. The first is to modify the defconfig file directly (not recommended); the second is to use the graphical menu interface (recommended).

Run the menuconfig_uboot command to modify the U-Boot configuration through the graphical interface.

After exiting, the settings are saved to:

u-boot-2021.10/build/cv1842hp_wevb_0014a_spinor/.config

The u-boot.bin produced by a native U-Boot build cannot be burned directly to FLASH. We use the Firmware Image Package (FIP) method from the ARM Trusted Firmware Design, which packages uboot.bin into fip.bin; fip_spl.bin is the image file loaded during fast boot.