Hello Andreas,
On 04/03/2013 04:50 PM, Andreas Bießmann wrote: > The kernel states: > > ---8<--- > The OMAP3 GPMC hardware BCH engine computes remainder polynomials, it does not > provide automatic error location and correction: this step is implemented > using > the BCH library. > --->8--- > > And we do so in u-boot. > > This implementation uses the same layout for BCH8 but it is fix. The current > provided layout does only work with 64 Byte OOB. > > Signed-off-by: Andreas Bießmann <andreas.de...@googlemail.com> > Cc: Tom Rini <tr...@ti.com> > Cc: Ilya Yanok <ilya.ya...@cogentembedded.com> > Cc: Scott Wood <scottw...@freescale.com> > Cc: Mansoor Ahamed <mansoor.aha...@ti.com> > --- > since v1: > * cleanups (remove debug stuff) > * make checkpach clean (still 2 warnings which I will not fix) > * merge some code with the AM33XX implementation > > since v2: > * fix all checkpatch warnings > * add more comments > * add NAND section in README.omap3 > > doc/README.omap3 | 19 +++ > drivers/mtd/nand/omap_gpmc.c | 367 > +++++++++++++++++++++++++++++++----------- > lib/Makefile | 2 +- > 3 files changed, 296 insertions(+), 92 deletions(-) > > diff --git a/doc/README.omap3 b/doc/README.omap3 > index 0a37de0..56aca8e 100644 > --- a/doc/README.omap3 > +++ b/doc/README.omap3 > @@ -145,6 +145,25 @@ int omap3_dma_wait_for_transfer(uint32_t chan) > int omap3_dma_get_revision(uint32_t *minor, uint32_t *major) > Read silicon Revision of the DMA module > > +NAND > +==== > + > +Ther eare some OMAP3 devices out ther with NAND attached. Due to the fact > that ther -> there > +OMAP3 ROM code can only handle 1-bit hamming ECC for accessing first page > +(place where SPL lives) we require this setup for u-boot at least when > reading > +the second progam within SPL. A lot of newer NAND chips however require more > +than 1-bit ECC for the pages, some can live with 1-bit for the first page. To > +handle this we can switch to another ECC algorithm after reading the payload > +within SPL. > + > +BCH8 > +---- > + > +To enable hardware assisted BCH8 (8-bit BCH [Bose, Chaudhuri, Hocquenghem]) > on > +OMAP3 devices we can use the BCH library in lib/bch.c. To do so add > CONFIG_BCH > +to enable the library and CONFIG_NAND_OMAP_BCH8 to your board config. > +The NAND OOB layout is the same as in linux kernel, if the linux kernel BCH8 > +implementation for OMAP3 works for you so the u-boot version should also. > > Acknowledgements > ================ > Thomas _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot