[U-Boot] [PATCH] ppc4xx: Canyonlands: Change EBC bus config to drive always (no high-z)

[Stefan Roese]

On Thursday 29 October 2009 18:44:31 Stefan Roese wrote:
> This patch fixes a problem only seen very occasionally on Canyonlands.
> The NOR flash interface (CFI driver) doesn't work reliably in all cases.
> Erasing and/or programming sometimes doesn't work. Sometimes with
> an error message, like "flash not erased" when trying to program an
> area that should have just been erased. And sometimes without any error
> messages. As mentioned above, this problem was only seen rarely and with
> some PLL configuration (CPU speed, EBC speed).
> 
> Now I spotted this problem a few times, when running my Canyonlands with
> the following setup (chip_config):
> 
> 1000-nor         - NOR  CPU:1000 PLB: 200 OPB: 100 EBC: 100
> 
> Changing the EBC configuration to not release the bus into high
> impedance state inbetween the transfers (ATC, DTC and CTC bits set to 1
> in EBC0_CFG) seems to fix this problem. I haven't seen any failure
> anymore with this patch applied.

Applied to u-boot-ppc4xx/master. Thanks.
 
Cheers,
Stefan

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