[Cbe-oss-dev] [FYI 24/27] ps3: storage driver

[Arnd Bergmann]

On Wednesday 29 November 2006 19:58, Geoff Levand wrote:
> 
> > Ah, ok. There may be some value in representing the flash part as MTD
> > instead of a raw block device then. That should at least handle writes
> > more efficiently than your current read-modify-write cycle.
> 
> Do you mean just in terms of speed, or also static memory usage?  If it is
> considerable re-work to set this up as MTD, I don't know if there will be
> much advantage just for improving write speed since it will be a rare occasion
> for the user to reprogram the bootloader.  What do you think?

It won't get around the 256kb vmalloc space for storing data on a
read-modify-write cycle, but the algorithm used by drivers/mtd/mtdblock.c
should be faster. If that is not relevant, then you can just as well
leave the current code there.

Is there actually a file system present in the 4MB flash area, or just
a kernel+ramdisk? If there is no fs at all, it may be a good idea to
not do a block driver at all, but simply a misc character device
that you can write the bootloader to and have it do the actual write
when closing the device. This would be similar to what the IBM
blades do for firmware update, but better ;-).

	Arnd <><