Frequently Asked Questions
i.MX51 EVK Linux Reference Manual
34-2
Freescale Semiconductor
2. Mount the JFFS2 file system on the target system:
The JFFS2 file system can be mounted on one of the MTD partitions. The partition table is set up
in two ways: static and dynamic. If no RedBoot partition is created when Linux boots on the target,
a static partition table is used from the MTD map driver source code (
mxc_nor.c
for example).
Otherwise, the RedBoot partition is used instead of the static one.
In most cases, it is more flexible to set up a partition in RedBoot for JFFS2 that can be used by
Linux. To do this, use RedBoot to program (use
fis create
) the newly created JFFS2 image into
the Flash on some unused space and then create a partition using
fis create
.
The following example illustrates how to do this in more detail.
RedBoot> fis list
Name FLASH addr Mem addr Length Entry point
RedBoot 0xA0000000 0xA0000000 0x00040000 0x00000000
kernel 0xA0100000 0x00100000 0x00200000 0x00100000
root 0xA0300000 0x00300000 0x00D00000 0x00300000
jffs2 0xA1200000 0xA1200000 0x00200000 0xFFFFFFFF
FIS directory 0xA1FE0000 0xA1FE0000 0x0001F000 0x00000000
RedBoot config 0xA1FFF000 0xA1FFF000 0x00001000 0x00000000
The above shows that a RedBoot partition called
jffs2
is created which contains the JFFS2 image
inside the Flash. When booting Linux, the kernel is able to recognize the RedBoot partitions and
create MTD partitions correspondingly when
CONFIG_MTD_REDBOOT_PARTS=y
is in the kernel
configuration (it is the default configuration on all i.MX platforms). With the above example, the
Linux kernel boot message shows:
Searching for RedBoot partition table in phys_mapped_flash at offset0x1fe0000
6 RedBoot partitions found on MTD device phys_mapped_flash
Creating 6 MTD partitions on "phys_mapped_flash":
0x00000000-0x00040000 : "RedBoot"
0x00100000-0x00300000 : "kernel"
0x00300000-0x01000000 : "root"
0x01200000-0x01400000 : "jffs2"
0x01fe0000-0x01fff000 : "FIS directory"
The JFFS2 is the fourth MTD partition under Linux in this case. To mount this MTD partition after
booting Linux, type:
cd /tmp
mkdir jffs2
mount -t jffs2 /dev/mtdblock/3 /tmp/jffs2
This mounts
/dev/mtdblock/3
to the
/tmp/jffs2
directory as the JFFS2 file system (directory name can be
something other than
jffs2
). The static partition method uses the partition table defined in the NOR MTD
map driver source code. The way to mount it is very similar to what is described above.
34.3
NFS Mounting Root File System
1. Assuming the root file system is under
/tmp/fs
, modify the
/etc/exports
file on the Linux host by
adding the following line:
/tmp/fs *(rw,no_root_squash)
2. Make sure the NFS service is started on the Linux host machine. To start it on the host machine,
issue:
service nfs start
InstallNFS RPM if not already installed.
Summary of Contents for i.MX51 EVK
Page 1: ...Part Number 924 76374 Rev 10 11 01 11 2010 i MX51 EVK Linux Reference Manual...
Page 14: ...i MX51 EVK Linux Reference Manual xiv Freescale Semiconductor...
Page 18: ...i MX51 EVK Linux Reference Manual xviii Freescale Semiconductor...
Page 24: ...i MX51 EVK Linux Reference Manual xxiv Freescale Semiconductor...
Page 38: ...Machine Specific Layer MSL i MX51 EVK Linux Reference Manual 2 8 Freescale Semiconductor...
Page 52: ...MC13892 Digitizer Driver i MX51 EVK Linux Reference Manual 5 4 Freescale Semiconductor...
Page 64: ...TV Encoder TVE Driver i MX51 EVK Linux Reference Manual 10 4 Freescale Semiconductor...
Page 82: ...Video for Linux Two V4L2 Driver i MX51 EVK Linux Reference Manual 12 8 Freescale Semiconductor...
Page 86: ...i MX5 Dual Display i MX51 EVK Linux Reference Manual 13 4 Freescale Semiconductor...
Page 100: ...X Windows Acceleration i MX51 EVK Linux Reference Manual 16 6 Freescale Semiconductor...
Page 118: ...Low Level Keypad Driver i MX51 EVK Linux Reference Manual 20 6 Freescale Semiconductor...
Page 134: ...Security Drivers i MX51 EVK Linux Reference Manual 22 10 Freescale Semiconductor...
Page 148: ...Inter IC I2C Driver i MX51 EVK Linux Reference Manual 24 4 Freescale Semiconductor...
Page 178: ...ARC USB Driver i MX51 EVK Linux Reference Manual 29 10 Freescale Semiconductor...
Page 194: ...OProfile i MX51 EVK Linux Reference Manual 33 6 Freescale Semiconductor...
