Documentation/blackfin/Filesystems

   1 /*
   2  * File:         Documentation/blackfin/Filesystems
   3  * Based on:
   4  * Author:
   5  *
   6  * Created:
   7  * Description:  This file contains the simple DMA Implementation for Blackfin
   8  *
   9  * Rev:          $Id: Filesystems 2384 2006-11-01 04:12:43Z magicyang $
  10  *
  11  * Modified:
  12  *               Copyright 2004-2006 Analog Devices Inc.
  13  *
  14  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
  15  *
  16  */
  17
  18                 How to mount the root file system in uClinux/Blackfin
  19                 -----------------------------------------------------
  20
  21 1       Mounting EXT3 File system.
  22         ------------------------
  23
  24         Creating an EXT3 File system for uClinux/Blackfin:
  25
  26
  27 Please follow the steps to form the EXT3 File system and mount the same as root
  28 file system.
  29
  30 a       Make an ext3 file system as large as you want the final root file
  31         system.
  32
  33                 mkfs.ext3  /dev/ram0 <your-rootfs-size-in-1k-blocks>
  34
  35 b       Mount this Empty file system on a free directory as:
  36
  37                 mount -t ext3 /dev/ram0  ./test
  38                         where ./test is the empty directory.
  39
  40 c       Copy your root fs directory that you have so carefully made over.
  41
  42                 cp -af  /tmp/my_final_rootfs_files/* ./test
  43
  44                 (For ex: cp -af uClinux-dist/romfs/* ./test)
  45
  46 d       If you have done everything right till now you should be able to see
  47         the required "root" dir's (that's etc, root, bin, lib, sbin...)
  48
  49 e       Now unmount the file system
  50
  51                 umount  ./test
  52
  53 f       Create the root file system image.
  54
  55                 dd if=/dev/ram0 bs=1k count=<your-rootfs-size-in-1k-blocks> \
  56                 > ext3fs.img
  57
  58
  59 Now you have to tell the kernel that will be mounting this file system as
  60 rootfs.
  61 So do a make menuconfig under kernel and select the Ext3 journaling file system
  62 support under File system --> submenu.
  63
  64
  65 2.      Mounting EXT2 File system.
  66         -------------------------
  67
  68 By default the ext2 file system image will be created if you invoke make from
  69 the top uClinux-dist directory.
  70
  71
  72 3.      Mounting CRAMFS File System
  73         ----------------------------
  74
  75 To create a CRAMFS file system image execute the command
  76
  77         mkfs.cramfs ./test cramfs.img
  78
  79         where ./test is the target directory.
  80
  81
  82 4.      Mounting ROMFS File System
  83         --------------------------
  84
  85 To create a ROMFS file system image execute the command
  86
  87         genromfs -v -V "ROMdisk" -f romfs.img -d ./test
  88
  89         where ./test is the target directory
  90
  91
  92 5.      Mounting the JFFS2 Filesystem
  93         -----------------------------
  94
  95 To create a compressed JFFS filesystem (JFFS2), please execute the command
  96
  97         mkfs.jffs2 -d ./test -o jffs2.img
  98
  99         where ./test is the target directory.
 100
 101 However, please make sure the following is in your kernel config.
 102
 103 /*
 104  * RAM/ROM/Flash chip drivers
 105  */
 106 #define CONFIG_MTD_CFI 1
 107 #define CONFIG_MTD_ROM 1
 108 /*
 109  * Mapping drivers for chip access
 110  */
 111 #define CONFIG_MTD_COMPLEX_MAPPINGS 1
 112 #define CONFIG_MTD_BF533 1
 113 #undef CONFIG_MTD_UCLINUX
 114
 115 Through the u-boot boot loader, use the jffs2.img in the corresponding
 116 partition made in linux-2.6.x/drivers/mtd/maps/bf533_flash.c.
 117
 118 NOTE -  Currently the Flash driver is available only for EZKIT. Watch out for a
 119         STAMP driver soon.
 120
 121
 122 6.      Mounting the NFS File system
 123         -----------------------------
 124
 125         For mounting the NFS please do the following in the kernel config.
 126
 127         In Networking Support --> Networking options --> TCP/IP networking -->
 128                 IP: kernel level autoconfiguration
 129
 130         Enable BOOTP Support.
 131
 132         In Kernel hacking --> Compiled-in kernel boot parameter add the following
 133
 134                 root=/dev/nfs rw ip=bootp
 135
 136         In File system --> Network File system, Enable
 137
 138                 NFS file system support --> NFSv3 client support
 139                 Root File system on NFS
 140
 141         in uClibc menuconfig, do the following
 142         In Networking Support
 143                 enable Remote Procedure Call (RPC) support
 144                         Full RPC Support
 145
 146         On the Host side, ensure that /etc/dhcpd.conf looks something like this
 147
 148                 ddns-update-style ad-hoc;
 149                 allow bootp;
 150                 subnet 10.100.4.0 netmask 255.255.255.0 {
 151                 default-lease-time 122209600;
 152                 max-lease-time 31557600;
 153                 group {
 154                         host bf533 {
 155                                 hardware ethernet 00:CF:52:49:C3:01;
 156                                 fixed-address 10.100.4.50;
 157                                 option root-path "/home/nfsmount";
 158                         }
 159                 }
 160
 161         ensure that /etc/exports looks something like this
 162                 /home/nfsmount *(rw,no_root_squash,no_all_squash)
 163
 164          run the following commands as root (may differ depending on your
 165          distribution) :
 166                 -  service nfs start
 167                 -  service portmap start
 168                 -  service dhcpd start
 169                 -  /usr/sbin/exportfs