On 20 July 2015 at 15:08, Brian Norris <[email protected]> wrote: > Hi Ezequiel, > > On Sun, May 24, 2015 at 03:42:11PM -0300, Ezequiel Garcia wrote: >> On 05/20/2015 11:43 AM, Antoine Tenart wrote: >> [..] >> >> >> >> I just had a look on the datasheet, and I you're right, the nand should >> >> support JDEC. However I get a "No NAND device found" error when >> >> reverting this patch. >> >> >> >> It seems nand_flash_detect_jedec() is not reading "JDEC" and is returning >> >> directly. I'm having a look at this. >> > >> > So, I can read 'J', 'E', 'D' and 'E' but then I got 0xff's. So I tried >> > to only check of JEDE in nand_flash_detect_jedec() but the JEDEC >> > parameter page was then not valid. >> > >> >> This uncovers two different bugs in the driver. >> >> 1. read_id_bytes is either '2' or '4', but JEDEC detections needs at >> least 5 bytes. >> >> 2. The initial buffer (to read the ID and the parameter page) has >> 256 bytes, but the JEDEC parameter page is 512-bytes. >> >> And while at it, the driver doesn't seem to support reading the >> redundant parameter pages (recently reported on barebox ML [1]). So this >> is a third bug. >> >> Would you try setting read_id_bytes to '5' and also increasing the READ_PARAM >> transfer length? Something like this: > > I'm trying to parse through the latest pxa3xx_nand patches, and I'm a > bit lost. Did this piece get dropped on the floor? >
As far as I can see, yes. Regarding this particular patch, the flash device supports JEDEC detection but the driver needs a fix. Hopefully, Antoine will submit a fix in the future. > At any rate, it looks like there are a few more things to fix in > Antoine's latest work, so I can't quite take them. Correct me if I'm > misunderstanding. > The current patchset under discussion is "v2 mtd: pxa3xx_nand: rework the timing setup": http://lists.infradead.org/pipermail/linux-mtd/2015-July/060033.html We are trying to get that sorted out, so we can move to the Berlin SoC support. Cheers, -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
