DESK-MX6-L/Deployment/Customizing the splash screen

History
Issue Date	Notes
2021/07/16	First DESK release
2022/03/04	DESK-MX6-L 3.0.0 release
2023/04/11	DESK-MX6-L 4.0.0 release

Customizing the splash screen

Resources

For further details on splash screen support in U-Boot, please refer to:

• U-Boot Splash Screen Support
• U-Boot Bitmap Support

Environment variables

The following environment variables are used by U-Boot for loading a BMP image from the selected storage and displayed in the screen (read from framebuffer memory):

• splashimage: RAM address where the BMP image is loaded. Please note that it must be a 32-bit aligned address with a 0x2 offset (eg: 0x20000002)
• splashpos: image position (eg: splashpos=m,m, for centering the image)
• splashsize: image size in bytes (default value 0x400000)

The following environment variables are used for reading the splash image from the network:

• splashfile: the splash image filename (default value is splash_image.bmp) to be read from the network
• loadsplashfile loads the splash file from tftp in order to store the image in the internal storage device

Then, the following command is used for reading the image from the used storage device:

• loadsplash: command for loading the BMP image from the storage device (e.g flash memory) to RAM. This command is automatically run by U-Boot when it executes bootcmd

Splash image in NOR SPI flash

The following command is used to store in NOR SPI flash a BMP image loaded via tftp:

spi_updatesplash=sf probe; sf erase 0xA00000 +${filesize}; sf write ${loadaddr} 0xA00000 ${filesize}

so, it is possibile to read a splash image from tftp and store it in NOR SPI:

run loadsplashfile
run spi_updatesplash

Splash image in NAND flash

The following command is used to store in NAND flash a BMP image loaded via tftp (please note that the NAND mtd partition for the splash image (nand-splash) is defined using the mtdparts parameter, and then referenced by the nand {erase,read,write} commands):

nand_updatesplash=nand erase.part nand-splash; nand write ${loadaddr} nand-splash ${filesize}

so, it is possibile to read a splash image from tftp and store it in NAND:

run loadsplashfile
run nand_updatesplash

Splash image in SD/eMMC

If an SD card or a eMMC device is used as boot device, the splashscreen image is directly loaded from the storage device.

In this example, the first partition - FAT format - is used directly reading the ${splashimage} BMP file.

mmc_loadsplash=fatload mmc ${mmcdev}:1 ${loadaddr} ${splashfile}; cp.b ${loadaddr} ${splashimage} ${filesize}

so, it is possibile to read directly a splash image from the eMMC partition:

loadsplash=run mmc_loadsplash

---