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Author	SHA1	Message	Date
David Howells	da4458bda2	NOMMU: Make it possible for RomFS to use MTD devices directly Change RomFS so that it can use MTD devices directly - without the intercession of the block layer - as well as using block devices. This permits RomFS: (1) to use the MTD direct mapping facility available under NOMMU conditions if the underlying device is directly accessible by the CPU (including XIP); (2) and thus to be used when the block layer is disabled. RomFS can be configured with support just for MTD devices, just for Block devices or for both. If RomFS is configured for both, then it will treat mtdblock device files as MTD backing stores, not block layer backing stores. I tested this using a CONFIG_MMU=n CONFIG_BLOCK=n kernel running on my FRV board with a RomFS image installed on the mtdram test device. I see my test program being run XIP: # cat /proc/maps ... c0c000b0-c0c01f8c r-xs 00000000 1f:00 144 /mnt/doshm ... GDB on the kernel can be used to show that these addresses are within the set-aside RAM space. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Bernd Schmidt <bernd.schmidt@analog.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>	2009-03-24 09:01:32 +00:00
Linus Torvalds	1da177e4c3	Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!	2005-04-16 15:20:36 -07:00

Author

SHA1

Message

Date

David Howells

da4458bda2

NOMMU: Make it possible for RomFS to use MTD devices directly

Change RomFS so that it can use MTD devices directly - without the intercession
of the block layer - as well as using block devices.

This permits RomFS:

 (1) to use the MTD direct mapping facility available under NOMMU conditions if
     the underlying device is directly accessible by the CPU (including XIP);

 (2) and thus to be used when the block layer is disabled.

RomFS can be configured with support just for MTD devices, just for Block
devices or for both.  If RomFS is configured for both, then it will treat
mtdblock device files as MTD backing stores, not block layer backing stores.

I tested this using a CONFIG_MMU=n CONFIG_BLOCK=n kernel running on my FRV
board with a RomFS image installed on the mtdram test device.  I see my test
program being run XIP:

	# cat /proc/maps
	...
	c0c000b0-c0c01f8c r-xs 00000000 1f:00 144        /mnt/doshm
	...

GDB on the kernel can be used to show that these addresses are within the
set-aside RAM space.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

2009-03-24 09:01:32 +00:00

Linus Torvalds

1da177e4c3

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

2005-04-16 15:20:36 -07:00

2 Commits