On Friday 09 May 2014 19:09:15 Ezequiel Garcia wrote:

# time nanddump /dev/mtd5 -f /dev/null -q
real    0m 5.82s
user    0m 0.20s
sys     0m 5.60s

Jason: Care to submit a proper patch?

On 08 May 04:56 PM, Arnd Bergmann wrote:

quoted

Ok, that is a noticeable difference. For scale, what is the size of that partition?

The board is Openblocks A6, running mainline.

# cat /proc/mtd 
dev:    size   erasesize  name
mtd0: 00090000 00004000 "uboot"
mtd1: 00044000 00004000 "env"
mtd2: 00024000 00004000 "test"
mtd3: 00400000 00004000 "conf"
mtd4: 01d20000 00004000 "linux"
mtd5: 01dec000 00004000 "user"

Ok, so it takes 5.6 seconds in kernel mode to access 31MB, which comes down
to 5.60MB/s. That isn't very fast compared to the time the CPU should take
for those instructions, so I'm surprised it actually makes any difference
at all.

There isn't a usable slave DMA engine in Armada XP by chance?

	Arnd