On Wed, May 30, 2007 at 01:34:19PM +0200, Ulf Samuelsson wrote:
=> We also need to understand if we are talking about the same thing. I have this feeling that mtdparts exist to divide the rootfs into several areas while the dataflash partioning is there purely for U-boot purposes.
Hmm, does it mean that you do not want to share dataflash partitioning between U-Boot nad Linux?
The partion use is:
- AT91 bootstrap.
- U-boot environment
- U-boot image.
- Kernel image
- Root FS.
The sum of 1+2+3 is always 256kB due to df sector size. The only programmable value is the kernel size.
There are constrains I'd like to see implemented some generic way as well...
Nothing is ever written to the dataflash to indicate partion info and nothing is passed to Linux except rootfs start adress in bootargs.
Partitioning is stored inside U-Boot environment. In case this is written into dataflash, the above will not be true. Also Linux will share this partition map, but can be told to not do so and also some partitions can be read-only for Linux.
The df partion is just for setttins protection and (in my 1 year+ old patch) sets a few environment variables to contain the start adress of kernel & rootfs.
Can someone confirm that mtdparts is the right way to go?
It will definitely work for me the way I'm used to use it. I do not know what is "the right way" in your mind, but I will try to answer your questions as well as I can do.
(all my boards are using redundand environment which can be read and written also from Linux - for firmware upgrading purposes)
Best regards, ladis