On 02/05/13 11:57, Wolfgang Denk wrote: > Dear Igor Grinberg, > > In message <5110bdb2.8040...@compulab.co.il> you wrote: >> >>> Yes, struct bmp_header is a packed array with non-natural order of >>> entries; see also section "Bitmap file header" at [1]; we may consider >>> this a really stupid thing to do, but we have to live with this fact. >> >> It was not that stupid in times of DOS and Win 3.1 >> when int was 16 bits long (and DRAM was 64K or even less)... > > It was as stupid then, too. At that time, a large number of systems > with similar alignment requirements existed, and experience with these > existed, too. > > Do you remember the "The Ten Commandments for C Programmers"? If not, > look them up and check how old these are. Note especially the ``All > the world's a VAX'' part - this is exactly what we see here in > operation.
Yep. Agreed on this. Although, I don't know, if anyone of us would tell the same 20+ years ago... It is now we can... > > The design of the BMP header is just BRAINDEAD. That is for sure. > >>> Indeed, this should be documented. And eventually the bmp command >>> should print a warning message if it sees other alignment. >> >> Agreed on this also, but again what about the board brick case? > > There is a ton of ways to brick a board. Why should we add protection > for one special case while we agree to leave the 50 other ways > onfixed? Because, I think this one is a bit different because of the bmp header and also is of very high demand. > >> Should we add the check for alignment and if it does not properly aligned >> deny further bmp header processing along with printing a warning? > > Why should we? Who tells that this is not perfectly legal on the > running system? It might be perfectly legal, but we also consider a tons of work explaining why and how this should be done (needless to mention the amount of bricked boards). Instead of simplifying the case, and I think this is a special case, at least because of the high demand and user (who is not a programmer) selectable address, you want us to teach the whole world about the bmp header alignment issues? > > > Let me repeat it: U-Boot is a boot loader. It is not intended for > meddling by avarage Johnny Loser, but for system programmers who know > what they are doing. And anyone doing such things is well adviced to > _test_ his settings on the command line before storing these for > automatic use. As I mentioned before, omitting such tests is a sin > that carries with it its own punishment. What are you trying to say? Is it that the environment variables change and in particular the splash screen installation _must_ be done by a programmer? Hmm.. that does not sound good... -- Regards, Igor. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot