[U-Boot] [PATCH 1/2] Fix OneNAND ipl to read CONFIG_SYS_MONITOR_LEN

[Scott Wood <scottwood@freescale.com>]

On Fri, Apr 24, 2009 at 02:57:52PM +0900, Kyungmin Park wrote:
> Actually, I don't like the CONFIG_SYS_MONITOR_LEN approaches, now you
> are consider the bad block at 1.
> But we can also consider the bad block 2, if there two consecutive 2
> bad block at block 1, 2, we should define the CONFIG_SYS_MONITOR_LEN
> as 128KiB * 4 and reserved block block 4 always even though we use 2
> blocks.

There are two separate constants -- the length of data excluding bad
blocks, and the size of the region set aside for that data including bad
blocks.  CONFIG_SYS_MONITOR_LEN is the former.

We may need to do something special when writing back the environment to
find its location if there were any bad blocks, though.

> Right, we should consider bad block at IPL, so my recommendation is
> IPL + u-boot should be fit at block 0

We wouldn't be having this discussion if someone didn't have a u-boot
that didn't fit in block 0.

> 128KiB at OneNAND, 256KiB at Flex-OneNAND. In case of apollon. we
> should reduce the size as 128KiB for OneNAND side. If the IPL + u-boot
> size under 128KiB, Flex-OneNAND also can boot it.

For comparison, powerpc u-boots are pretty much never less than 128KiB,
and with the NAND subsystem are typically larger than 256KiB.  We may
need to boot from OneNAND some day.

> For simplicity How about to use block scheme? we always use block 0
> for boot (IPL + u-boot) whatever block size.

NACK.

-Scott