Trash Fr:MultiMediaCard
Instructions pour utiliser la MultiMediaCard (MMC/SD) sur votre carte Armadeus
Introduction
You can use standard MMC/SD cards with your Armadeus board, if you have the corresponding connector attached to your devt board. See MMC/SD page to know how to connect the hardware part.
Installation
when you build your kernel image, then modify your configuration:
[user@toto]$ make xconfig
in Device Drivers->MMC/SD Card support->iMX Support In FileSystems, don't forgt to add support for the filesystem 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:
[user@toto]$ make
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 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
Préparation de la SD/MMC
La plupart des SD/MMC commercialisées ne sont pas formatées correctement ou ne dispose pas de table de partition standard. Nous allons donc voir comment préparer notre SD/MMC toute neuve afin que celle-ci soit reconnue par notre console. Introduisez votre SD/MMC dans le lecteur de carte sur votre PC Linux. Il faut ensuite récupérer le nom du device assigné à la MMC (généralement /dev/sda1). Si votre distribution monte automatiquement les périphériques de stockage USB, annulez ce montage. Pour récupérer le device de la MMC je regarde généralement dans /var/log/messages et je recherche le dernier message du type:
usb 5-7: new high speed USB device using ehci_hcd and address 5 Initializing USB Mass Storage driver... scsi7 : SCSI emulation for USB Mass Storage devices usbcore: registered new driver usb-storage USB Mass Storage support registered. sd 7:0:0:1: Attached scsi generic sg2 type 0 Vendor: Hama Model: CardReaderMMC/SD Rev: 1.9C Type: Direct-Access ANSI SCSI revision: 00 SCSI device sdd: 501760 512-byte hdwr sectors (257 MB) sdd: Write Protect is off SCSI device sdd: 501760 512-byte hdwr sectors (257 MB) sdd: Write Protect is off sdd: sdd1 sd 7:0:0:2: Attached scsi removable disk sdd sd 7:0:0:2: Attached scsi generic sg3 type 0
Ici ma MMC de 256 Mo s'est vue assignée /dev/sdd1.
Maintenant avec fdisk, étudions un peu le contenu de notre carte:
# /sbin/fdisk /dev/sdd1
Command (m for help): p
Disk /dev/sdd1: 256 MB, 256884736 bytes
16 heads, 32 sectors/track, 979 cylinders
Units = cylinders of 512 * 512 = 262144 bytes
This doesn't look like a partition table
Probably you selected the wrong device.
Device Boot Start End Blocks Id System
/dev/sdd1p1 ? 1519797 3749308 570754815+ 72 Unknown
Partition 1 has different physical/logical beginnings (non-Linux?):
phys=(357, 116, 40) logical=(1519796, 11, 5)
Partition 1 has different physical/logical endings:
phys=(357, 32, 45) logical=(3749307, 11, 3)
Partition 1 does not end on cylinder boundary.
/dev/sdd1p2 ? 329472 4110777 968014120 65 Novell Netware 386
Partition 2 has different physical/logical beginnings (non-Linux?):
phys=(288, 115, 43) logical=(329471, 11, 19)
Partition 2 has different physical/logical endings:
phys=(367, 114, 50) logical=(4110776, 14, 2)
Partition 2 does not end on cylinder boundary.
/dev/sdd1p3 ? 3652113 7433418 968014096 79 Unknown
Partition 3 has different physical/logical beginnings (non-Linux?):
phys=(366, 32, 33) logical=(3652112, 3, 26)
Partition 3 has different physical/logical endings:
phys=(357, 32, 43) logical=(7433417, 4, 25)
Partition 3 does not end on cylinder boundary.
/dev/sdd1p4 ? 1 7103958 1818613248 d Unknown
Partition 4 has different physical/logical beginnings (non-Linux?):
phys=(372, 97, 50) logical=(0, 0, 1)
Partition 4 has different physical/logical endings:
phys=(0, 10, 0) logical=(7103957, 15, 32)
Partition 4 does not end on cylinder boundary.
Partition table entries are not in disk order
Comme vous pouvez le constater, c'est un peu le fouillis sur cette carte. Effaçons toute les partitions:
Command (m for help): d
Partition number (1-4): 1
Command (m for help): d
Partition number (1-4): 2
Command (m for help): d
Partition number (1-4): 3
Command (m for help): d
Selected partition 4
Command (m for help): p
Disk /dev/sdd1: 256 MB, 256884736 bytes
16 heads, 32 sectors/track, 979 cylinders
Units = cylinders of 512 * 512 = 262144 bytes
Device Boot Start End Blocks Id System
Puis créons une partition Linux. Afin de ne pas payer de royalties inutilement pour notre console nous choisissons bien sûr de ne pas utiliser de type de fichier FAT.
Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 1 First cylinder (1-979, default 1): Using default value 1 Last cylinder or +size or +sizeM or +sizeK (1-979, default 979): Using default value 979
Finalement, sauvons nos modifications et quittons fdisk:
Command (m for help): p
Disk /dev/sdd1: 256 MB, 256884736 bytes
16 heads, 32 sectors/track, 979 cylinders
Units = cylinders of 512 * 512 = 262144 bytes
Device Boot Start End Blocks Id System
/dev/sdd1p1 1 979 250608 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 22: Invalid argument.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
Il ne nous reste plus désormais qu'à formatter la MMC:
# /sbin/mkfs.ext2 /dev/sdd1
mke2fs 1.38 (30-Jun-2005)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
62744 inodes, 250864 blocks
12543 blocks (5.00%) reserved for the super user
First data block=1
31 block groups
8192 blocks per group, 8192 fragments per group
2024 inodes per group
Superblock backups stored on blocks:
8193, 24577, 40961, 57345, 73729, 204801, 221185
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 20 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
Voilà la carte est prête à être utilisée (à supposer qu'il existe un point de montage /mnt/mmc):
# mount /dev/sdd1 /mnt/mmc/ # ls -al /mnt/mmc/ total 17 drwxr-xr-x 3 root root 1024 2007-01-15 12:56 . drwxr-xr-x 4 root root 4096 2007-01-15 12:58 .. drwx------ 2 root root 12288 2007-01-15 12:56 lost+found
Copiez maintenant vos données sur la MMC:
$ cp /mnt/mmc/
Voilà il ne reste plus qu'à démonter la MMC (en tant que root) et la mettre sur l'APF9328
# umount /mnt/mmc
Utilisation
Le driver MMC étant désormais statique au noyau, pas besoin de charger de module. Insérez votre MMC et vérifiez qu'elle est bien détectée:
imx-mmc imx-mmc.0: card inserted mmcblk0: mmc0:0001 MMC 250880KiB mmcblk0: p1
Montons la MMC dans /media/mmc:
# mkdir -p /media/mmc # mount /dev/mmcblk0p1 /media/mmc/
