Dear Guennadi Liakhovetski, In message <[EMAIL PROTECTED]> you wrote: > > Erase area - this is all we erase, as opposed to one erase sector. On NOR > this is limited by the environment size, on NAND by the number of blocks - > the fifth parameter in the configuration file. This area may contain other > useful data, which is first read in, then the whole area is erased, the > environment is replaced in the read-in data, and it is written back - this > is what I call the back-up process in the code.
We should not do that. We should erase only those sectors / blocks that we are actually attemmpting to write to. > > And where's the difference between NAND and NOR flash? For NOR, the > > minimum "erase region" is a "block", either, which also can be 256KiB > > large. > > This patch enables this for NOR - NAND support comes first with patch 6. > So, it just enables placing the actual environment at any offset in the > "erase area". I don't understand. Why would such an offset be needed? The envrionment always starts right at the beginning of a sector or erase unit or block or however the storage device might call the smallest unit it can handle. > > > + /* > > > + * Support environment anywhere within erase sectors: read out the > > > + * complete area to be erased, replace the environment image, write > > > + * the whole block back again. > > > + */ > > This comment should actually serve as an explanation... But I don't understand it. What are "erase sectors"? How is the "area to be erased" defined? And what is the "block" (a flash block?) you are writing? > > You are talking about "several pages" above. Where is this refelected > > in the code? > > You mean in the commit comment? There I am talking about the future code - > NAND case, which is not yet in this patch. How shall anybody understand this, then? Description and code are not in sync - this is bad. > > Frankly, I don't understand what you are trying to do. Please explain > > your implementation. > > Hope, it is a bit clearer now. If not, please ask, will try to explain > again. You must provide a description of what you are actually doing. I do not understand your code. > Indeed, this patch series changes the programme in a non-trivial way, > that's why I had to split this "NAND-support" into several patches, still > some of them seem to be not clear enough. Well, splitting complex things that obviously belong together into smaller pieces and confronting the reviewer with a puzzle of unrelated bits does not exactly make things "clear". See previous message - I guess the whole splitting is just contra- productive. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: [EMAIL PROTECTED] If something is different, it's either better or worse, and usually both. - Larry Wall _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
