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U-Boot SD(Secured Digital card) Support

This section gives an overview of the SD(Secured Digital Card) support in U-Boot

l          Overview

SD (Secured Digital Card) support isavailable through HSMMC controller.

SD support is available by default in allU-Boot configs.  SD card can be access in all other boot modes (NAND/SPI/NOR).

l          Read and execute application from SD card

List files on a FAT32 formated SD card

TI8168_EVM# mmc rescan 0

TI8168_EVM# fatls mmc 0

l          Booting kernel image from the SD card

TI8168_EVM# mmc rescan 0

TI8168_EVM# fatload mmc 0 0x81000000 uImage

TI8168_EVM# bootm 0x81000000

l          Booting application (ex.u-boot.bin)image from the SD card

TI8168_EVM# mmc rescan 0

TI8168_EVM# fatload mmc 0 0x81000000 u-boot.bin

TI8168_EVM# go 0x81000000

Note: For the PSP_04.00.00.12and older release use the following mmc commands

$mmc rescan 0 must be replaced with$mmc init

$fatload mmc 0 <addr><file> must be replaced with $fatload mmc 1 <addr> <file>

l          Setting Up Boot Environment onSD Card

This section describes steps to be followedto create a standalone power-on bootable system on SD card.

l          Prerequisites Ensure thatfollowing is available:

• A Linux hostwith fdisk, sfdisk, mkfs.ext3 and mkfs.vfat utilities is available

• Copy images MLO, u-boot.bin, uImage, nfs.tar.gz and mksd-ti816x.sh from release package to a directory onthis Linux machine. For subsequent description, we will assume these files arecopied to /home/ti816x. Please refer Package Contents section in DM816x User Guide for location of these files.

• Empty SDcard (at least 256MB, preferably 4GB SDHC)

• A SD memorycard reader/programmer to copy files from Linux Host

  Note: The SD Boot has some specificrestriction about the format of the 1st partition and copying the MLO image.Soit is recommended that the supplied script mksd-ti816x.sh is used for creatingpartitions and copying files.

l          Steps

• Connect the SD memory card using Memory Card reader to the LinuxHost

• Note the name allotted for this device. We assume the device isnamed as "/dev/sdb"

• Navigate to the /home/ti816x directory where all the mentionedfiles are copied

• Ensure that the script mksd-ti816x.sh has executable permissions

• This scripts expects arguments in the following format

./mksd-ti816x.sh<sd-device-name> <sd-1st-stage-bootloader> <kernel-uImage><tar-gzipped-filesystem-directory>

• Note that the user will require root/sudo permissions

• In our example, we run the following command

sudo ./mksd-ti816x.sh/dev/sdb MLO u-boot.bin uImage nfs.tar.gz

• You will be asked about data getting overwritten, confirm it andthe files along with filesystem will be copied to SD card

• Note that this script will create two primary partitions:

• 1st partition is formatted as FAT32 containingMLO, u-boot.bin, uImage files

• 2nd partition is formatted as ext3where the filesystem is extracted in root

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