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* with a DevFull you can use the MMC/SD onboard connector and an adaptor for miniSD and microSD | * with a DevFull you can use the MMC/SD onboard connector and an adaptor for miniSD and microSD | ||
| − | + | All needed drivers are included in standard Armadeus Linux image. | |
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==Usage== | ==Usage== | ||
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(default bootcmd is ''run jffsboot'') | (default bootcmd is ''run jffsboot'') | ||
| − | == | + | ==Performances== |
| + | * [[MMC/SD#Supported_Cards]] | ||
| + | ==Installation (obsolete now because driver is included in default Armadeus kernel)== | ||
| + | |||
| + | When you build your kernel image, then modify its configuration: | ||
| + | [armadeus]$ make linux-menuconfig | ||
| + | in Device Drivers->MMC/SD Card support->iMX Support | ||
| + | In FileSystems, don't forget to add support for the filesystem you want to use on the MMC and if you activate FAT/VFAT, don't forget to activate Native Language Support (NLS) | ||
| + | otherwise you'll get errors like: | ||
| + | Unable to load NLS charset cp437 | ||
| + | FAT: codepage cp437 not found | ||
| + | |||
| + | Save your configuration and then rebuild your kernel image: | ||
| + | [armadeus]$ make linux | ||
| + | now you should have following drivers in your kernel source tree: | ||
| + | drivers/mmc/ | ||
| + | Copy '''mmc_core.ko''', '''imxmmc.ko''' & '''mmc_block.ko''' to your target root filessytem in '''/lib/modules/''' or reflash the generated rootfs. | ||
| + | |||
| + | If not already existing then create the MMC block devices: | ||
| + | # mknod /dev/mmcblk0 b 254 0 | ||
| + | # mknod /dev/mmcblk0p1 b 254 1 | ||
| + | If not already existing then create the mount point (/mnt/mmc): | ||
| + | # mkdir -p /mnt/mmc | ||
==Links== | ==Links== | ||
| − | * http:// | + | * http://en.wikipedia.org/wiki/MultiMedia_Card |
[[Image:FrenchFlag.png]][[Fr:MultiMediaCard| Cette page en français]] | [[Image:FrenchFlag.png]][[Fr:MultiMediaCard| Cette page en français]] | ||
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| + | [[Category:MassStorage]] | ||
Revision as of 18:57, 1 May 2008
Instructions to use the MultiMediaCard (MMC/SD) on your Armadeus board
Contents
Introduction
You can use standard MMC/SD/miniSD/microSD cards with your Armadeus board:
- with a DevLight V1 you must have the corresponding connector attached to your development board. and use an adaptor for miniSD and microSD
- with a DevLight V2 you can use the onboard microSD connector
- with a DevFull you can use the MMC/SD onboard connector and an adaptor for miniSD and microSD
All needed drivers are included in standard Armadeus Linux image.
Usage
Just mount the MMC like you will do on your PC, for example (FAT32 formatted card):
# mount -t vfat /dev/mmcblk0p1 /mnt/mmc
You can then access the MMC's files from /mnt/mmc directory
The MMC driver is now included inside the Linux kernel (no more a module) but if you want to use it as a module you will have to:
# modprobe imxmmc # modprobe mmc_block
Booting from MMC/SD
When your rootfs is too big to be put on the APF9328 FLASH, you can always use a MMC/SD like a Hard Drive and boot from it. To do that you must have MMC drivers compiled as builtin in your Linux kernel (done by default in standard Armadeus kernel)
- Mount your MMC/SD on your Host filesystem, for example in /media/mmc
[armadeus] $ sudo mkdir -p /media/mmc [armadeus] $ sudo mount /dev/sdxx /media/mmc
- Then put your rootfs on this MMC/SD: in Buildroot configure rootfs to be tar-ed:
[armadeus] $ make menuconfig Target filesystem options ---> tar the root filesystem [armadeus] $ make
and then:
[armadeus] $ sudo tar xvf ./buildroot/binaries/armadeus/rootfs.arm.tar -C /media/mmc [armadeus] $ sudo umount /media/mmc
- in U-Boot then use (with MMC/SD/microSD inserted):
BIOS> run mmcboot
- if you want to automatically boot from SD at each startup then replace default bootcmd U-Boot macro:
BIOS> setenv bootcmd run mmcboot BIOS> saveenv
(default bootcmd is run jffsboot)
Performances
Installation (obsolete now because driver is included in default Armadeus kernel)
When you build your kernel image, then modify its configuration:
[armadeus]$ make linux-menuconfig
in Device Drivers->MMC/SD Card support->iMX Support In FileSystems, don't forget to add support for the filesystem you want to use on the MMC and if you activate FAT/VFAT, don't forget to activate Native Language Support (NLS) otherwise you'll get errors like:
Unable to load NLS charset cp437 FAT: codepage cp437 not found
Save your configuration and then rebuild your kernel image:
[armadeus]$ make linux
now you should have following drivers in your kernel source tree:
drivers/mmc/
Copy mmc_core.ko, imxmmc.ko & mmc_block.ko to your target root filessytem in /lib/modules/ or reflash the generated rootfs.
If not already existing then create the MMC block devices:
# mknod /dev/mmcblk0 b 254 0 # mknod /dev/mmcblk0p1 b 254 1
If not already existing then create the mount point (/mnt/mmc):
# mkdir -p /mnt/mmc
