From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.free-electrons.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1eQgzN-0007jG-Fr for linux-mtd@lists.infradead.org; Sun, 17 Dec 2017 22:00:55 +0000 Date: Sun, 17 Dec 2017 23:00:32 +0100 From: Boris Brezillon To: Sean Nyekjaer Cc: Miquel RAYNAL , ezequiel.garcia@free-electrons.com, linux-mtd@lists.infradead.org, "Kasper Revsbech (KREV)" Subject: Re: [BUG] pxa3xx: wait time out when scanning for bb Message-ID: <20171217230032.30853780@bbrezillon> In-Reply-To: <461b45a8-de1f-0b54-567f-001ea30ee927@prevas.dk> References: <7df7abb5-e666-c999-e449-75762b551ea5@prevas.dk> <20171212095119.475de032@xps13> <727489cf-d1f6-8777-c6f4-981127657c9d@prevas.dk> <20171212111227.4946cc15@xps13> <20171212120806.7c31463f@xps13> <20171212123523.48185f21@xps13> <75bd6b87-12ed-4003-262a-b1bd03a62cbd@prevas.dk> <20171212134706.49f3c57e@xps13> <2f16ce90-6e00-c95f-7a81-5603d9acf574@prevas.dk> <20171212143512.3b62d3f5@xps13> <48EEEC1C-954B-42E5-92BE-A00AD97A5789@prevas.dk> <20171212192327.57b1fa80@xps13> <9f578b28-ef3b-8e84-0a8c-b70c494efff0@prevas.dk> <20171213094105.73646658@xps13> <20171215182512.2449af9e@xps13> <45D7D798-BA86-41CD-AB56-156C1BD7FCC4@prevas.dk> <20171215201955.2431195c@xps13> <7892957c-273b-ea58-1d50-b35e70c69e02@prevas.dk> <20171217141916.04e377ab@bbrezillon> <461b45a8-de1f-0b54-567f-001ea30ee927@prevas.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, 17 Dec 2017 22:47:26 +0100 Sean Nyekjaer wrote: > Hi Boris and Miquel > >>> > >>>> I also tried booting with ECC enabled and with that enabled the > >>>> driver is unable to read the bbt and marked all blocks bad. > >>> And if I understand correctly, if you remove nand-ecc-mode = "none" (or > >>> set it to "hw"), the kernel fails to find the BBT, that is right? > >> Yes. > >>> As I was not expecting such a quick answer, I did push another patch > >>> after sending my email that fixes an issue in mtdcore.c, please check > >>> you have it (there are a few "fixup!" patches, and on top of them you > >>> must find one which is a well-formatted patch about > >>> mtd_check_oob_ops()). > >> I have rebased on top of 9aee88a618f8 mtd: Fix mtd_check_oob_ops() > >>> I learned that today: to get a prompt while all blocks are bad, you can > >>> add: > >>> > >>> chip->options |= NAND_SKIP_BBTSCAN; > >>> > >>> Before nand_scan_tail(). > >>> > >>> If you can reach a prompt with the failing configuration and when you > >>> will have the time, I will welcome a dump of the same area as before > >>> so we will try to understand what is wrong now ! :) > >> Nice one, a lot easier to read whats happens > >> > >> nanddump of BBT without ECC enabled: > >> https://gist.github.com/anonymous/627e5be058ed93c106d61641f6aa5da0 > >> > >> nanddump of BBT with ECC enabled: > >> https://gist.github.com/anonymous/76b3240f156c6547cf76d59f2aae49fe > >> bootsnippet with ECC and NAND_SKIP_BBTSCAN enabled. > >> https://gist.github.com/anonymous/0d9be95cd9c36ff006f7aa03e7c2cc85 > >> > >> Please let me know what traces you need to fix the ECC :-) > > The dumps look good (at least, the BBT pattern is correct, we have the > > number of ECC bytes we expect and they are where we expect them). > > > > My gut feeling is that something is wrong with ECC (or something related > > to ECC) in u-boot. > > > > Can you try to let Linux create the BBT on its own and dump the last > > block as you did previously? > > > > So, to sum-up > > > > 1/ put the following in your DT > > > > nand-ecc-mode = "hw"; > > nand-on-flash-bbt; > > > > 2/ scrub the NAND from u-boot and make sure you don't reboot after that, > > so that u-boot can't recreate its own BBT. > > > > 3/ Let Linux boot and dump the pages (in raw mode) where BBTs created by > > Linux are supposed to be (should be the same addresses as before) > Trace with nand scrub in uboot and ecc enabled: > https://gist.github.com/anonymous/3ce389b9276fddbd46f59c89b99ee4ff > > Same as above with "chip->options |= NAND_SKIP_BBTSCAN;" in the marvell > nand driver > https://gist.github.com/anonymous/3aed159b5a5ee22f27403fe79ba97400 > > If I dump 0xFEC0000/0xFFC0000 or 0xFEE0000/0xFFE0000 (the bbt pages) > they contain > only 0xFF's as the kernel does not write to the blocks. > > To me it seem a little bit difficult to say why the new marvell nand driver > (with ecc enabled) thinks all the freshly scrubbed blocks are bad. Ok, now I really need the dump without the -n option. It seems that dumping in non-raw mode does not return the expected value. Thanks, Boris