This document provides a comprehensive overview of the partitions of all boot devices on SP7350 platform. The SP7350 platform supports 5 boot devices, including SPI-NOR flash, SPI-NAND flash, 8-bit NAND flash, eMMC device, and SD card.
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Partition | Size (kB) | Descriptions |
|---|---|---|
iboot | 96 | image of i-boot for external boot |
xboot | 192 | image of x-boot, including training firmware of DDR |
dtb | 128 | image of device-tree blob (not used) |
uboot | 768 | image of U-Boot |
fip | 864 | image of fip, including TF-A and OP-TEE |
uImage | Actual size of image | image of Linux kernel with built-in initramfs file-system |
Jffs2 file-system
In contrast, the jffs2 file-system resides in a dedicated partition within the SPI-NOR flash. Any alterations made to the root file-system are committed to the SPI-NOR flash. It's important to note that the performance of the jffs2 file-system may be sub-optimal due to the necessity to read and modify the flash.
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Partition | Size (kB) | Descriptions |
|---|---|---|
iboot | 96 | image of i-boot for external boot |
xboot | 192 | image of x-boot, including training firmware of DDR |
dtb | 128 | image of device-tree blob (not used) |
uboot | 768 | image of U-Boot |
fip | 864 | image of fip, including TF-A and OP-TEE |
kernel | Actual size of image | image of Linux kernel with U-Boot header |
rootfs | Depend on size of flash | image of jfffs2 root file-system |
Note
For those seeking to adjust partitions, it is crucial to update the definition of the environment variable 'mtdparts' in U-Boot. This adjustment can be made in the header file located at:
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Partition | Size | Descriptions |
|---|---|---|
nand_header | 1 block | header of the NAND flash |
xboot1 | Actual size of image | image of x-boot, including training firmware of DDR |
uboot1 | Actual size of image | image of U-Boot (factory default) |
uboot2 | Actual size of image | image of U-Boot (the latest update) |
fip | 2 MB | image of fip, including TF-A and OP-TEE |
env | 512 kB | image of environment variable of U-Boot |
env_redund | 512 kB | image of environment variable of U-Boot (redundant) |
dtb | 256 kB | image of device-tree blob (not used) |
kernel | 25 MB | image of Linux kernel with U-Boot header |
rootfs (ubifs) | Depend on size of flash | image of ubifs root file-system |
It is essential to ensure that the combined size of the nand_header, xboot1, uboot1, and uboot2 partitions does not exceed 4 MB. This constraint is crucial as the fip partition initiates at a 4 MB offset.
Note
To adjust partitions, please modify the define MTDPARTS_DEFAULT in the file:
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Partition | Size | Descriptions |
|---|---|---|
GPT | 17 kB | GUID partition table, including MBR, header and 128 partition table |
uboot1 | 1 MB | image of U-Boot (factory default) |
uboot2 | 1 MB | image of U-Boot (the latest update) |
fip | 1 MB | image of fip, including TF-A and OP-TEE |
env | 512 kB | image of environment variable of U-Boot |
env_redund | 512 kB | image of environment variable of U-Boot (redundant) |
dtb | 256 kB | image of device-tree blob (not used) |
kernel | 32 MB | image of Linux kernel with U-Boot header |
rootfs (ext4) | Depend on size of device | image of ubifs Linux ext4 root file-system |
SD card
The SP7350 platform offers support for booting from an SD card, providing a convenient solution for updating system images, particularly during the developmental stage or debugging. Although the SD card may exhibit lower performance compared to the eMMC device, its utility in certain scenarios remains valuable.
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