Messages in this thread | | | Subject | Re: [PATCH] UBI: add minimal amount of reserved erase blocks in Kconfig | From | Artem Bityutskiy <> | Date | Fri, 29 Jun 2012 17:10:30 +0300 |
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On Fri, 2012-06-29 at 09:17 +0200, Richard Genoud wrote: > 2012/6/28 Artem Bityutskiy <dedekind1@gmail.com>: > > On Thu, 2012-06-28 at 18:07 +0200, Richard Genoud wrote: > >> Agreed, it seems that 2% of the whole flash (at least for SLC device) > >> is more realistic. > > > > Agree, feel free to send a separate patch for this. > Done ! > > > >> > Frankly, I do not understand this logic :-) And your patch looks wrong - > >> > it touches the "auto-format" code which you may consider more like a > >> > "debugging" feature and should not rely on this in production. > >> Sorry, but I don't understand what you mean by the "auto-format" code. > > > > Yeah, right, this comment was incorrect, sorry. > > > > I was thinking that instead of giving to ubiattach the MBB, we could > give it the MBB percentage (maximum bad blocks percentage of the whole > flash device). > From this % and the whole flash size, we get the MBB number, and set > beb_rsvd_level for each MTD part.
Well, I thought that it may be not flexible enough for some people, because you cannot give 1.5%, since flaoting-point arithmetic in the kernel is not used.
> It will be easier for userspace, as we won't have to set a different > value for different flash size. The default 2% value will (almost) > always be correct. > We can even get rid of the CONFIG_MTD_UBI_BEB_RESERVE option.
Yes, this option would be killed.
> BTW, the real killer feature would be that the flash gives its NVB or > MBB value in response to the READ_ID command, but unfortunately that's > not the case...
Sure, you can also implement this. Add the corresponding field to 'struct mtd_info', 0 will mean "not known". UBI could pick it.
-- Best Regards, Artem Bityutskiy [unhandled content-type:application/pgp-signature] | |