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Altera_Forum
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16 years ago

Linux with MMU on NEEK

Hi, all. I'm testing Linux MMU version, on my NEEK. http://www.nioswiki.com/linux It works fine and I can use "bash" shell. This is the evident proof that we are using the true 'fo...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Hi.

I ported a SD-SPI IP to my NEEK according to the instruction 

http://www.alteraforum.com/forum/showthread.php?t=18875
.

The boot messages are 


mmc_spi spi2.0: ASSUMING SPI bus stays unshared! 
mmc_spi spi2.0: ASSUMING 3.2-3.4 V slot power 
mmc_spi spi2.0: SD/MMC host mmc0, no DMA, no WP, no poweroff 
TCP cubic registered 
NET: Registered protocol family 17 
RPC: Registered udp transport module. 
RPC: Registered tcp transport module. 
mmc0: host does not support reading read-only switch. assuming write-enable. 
mmc0: new SD card on SPI 
mmcblk0: mmc0:0000 SD01G 968 MiB  
mmcblk0:
.

So I hit the command 'mount -t vfat /dev/mmcblk0 /mnt', but it claims 'No such device or address'. I wondered and searched the cause in the kernel carefully, but could'nt find the bug. It clearly initializes the SD driver and reads informations... Finally I saw the Manpage of 'mount(2)' and knew the exact meaning of 'ENXIO'. It saies that 'The major number of the block device source is out of range'.

In the file '/home/***/nios2-linux/uClinux-dist/vendors/Altera/nios2/device_table.txt' 

#  mmc block devices
/dev/mmc0    b    640    0    0    197    0    0    1    -
/dev/mmcblk0    b    640    0    0    197    0    0    1    -
/dev/mmcblk0p1    b    640    0    0    197    1    0    1    -
/dev/mmcblk0p2    b    640    0    0    197    2    0    1    -
/dev/mmcblk0p3    b    640    0    0    197    3    0    1    -
Of cource, the true major number of 'mmc' is 179... Hey, Give me a break!

Kazu