From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Pringlemeir To: Stefan Agner Subject: Re: [RFC 2/5] mtd:fsl_nfc: Add hardware 45 byte BHC-ECC support for 24 bit corrections. References: <87siupheou.fsf@nbsps.com> <1389222441-4322-1-git-send-email-bpringlemeir@nbsps.com> <1389222441-4322-3-git-send-email-bpringlemeir@nbsps.com> <127db6b73356442d2ba12e8c011038cc@agner.ch> <87r3zaxgtr.fsf@nbsps.com> <87lhphyjkg.fsf@nbsps.com> <0bc8cec13bcf5b9cbea9cd3345815e4a@agner.ch> <8761dit9u9.fsf@nbsps.com> Date: Mon, 02 Mar 2015 10:05:36 -0500 Message-ID: <87k2yzqw1r.fsf@nbsps.com> MIME-Version: 1.0 Content-Type: text/plain Cc: b21989@freescale.com, linux-mtd@lists.infradead.org, Jason.jin@freescale.com, linux-arm-kernel@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 28 Feb 2015, stefan@agner.ch wrote: > The flash chip mentioned above requires 8-bit error correction per 512 > byte block, hence I increased the ECC to the maximum available level > (60-byte ECC, see page below). One thing which is not very nice, in > order to fit the 60-byte ECC into the 64-byte OOB, I had to shorten > the BBT pattern and set it at the very beginning of the page. This > works fine, however this basically sets the page also to factory bad, > I'm not sure if this is ok? Otherwise, we also could use a BBT pattern > of length 1 (used by cafe_nand.c too). I guess that is a DT option? I wouldn't be an expert on this. So submitting it to the linux-mtd is good. I am also not sure if the HW ECC will work with 'sub-pages'. I think a college of your at Toradex submitted a patch to the u-boot. I am pretty sure that it could work with software ECC, but maybe disabling it is easiest. > What do you think? I would like to respin the NFC patch, with my > U-Boot changes and this change included... Please go ahead. Markus M is also using the fsl_nfc driver on a Freescale MPC5125 board, so it is probably good to copy your patches to him. At least, he can test on a BE platform. People also complained about JFFS and this version of the driver. I didn't investigate that. Thanks, Bill Pringlemeir. From mboxrd@z Thu Jan 1 00:00:00 1970 From: bpringlemeir@nbsps.com (Bill Pringlemeir) Date: Mon, 02 Mar 2015 10:05:36 -0500 Subject: [RFC 2/5] mtd:fsl_nfc: Add hardware 45 byte BHC-ECC support for 24 bit corrections. References: <87siupheou.fsf@nbsps.com> <1389222441-4322-1-git-send-email-bpringlemeir@nbsps.com> <1389222441-4322-3-git-send-email-bpringlemeir@nbsps.com> <127db6b73356442d2ba12e8c011038cc@agner.ch> <87r3zaxgtr.fsf@nbsps.com> <87lhphyjkg.fsf@nbsps.com> <0bc8cec13bcf5b9cbea9cd3345815e4a@agner.ch> <8761dit9u9.fsf@nbsps.com> Message-ID: <87k2yzqw1r.fsf@nbsps.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 28 Feb 2015, stefan at agner.ch wrote: > The flash chip mentioned above requires 8-bit error correction per 512 > byte block, hence I increased the ECC to the maximum available level > (60-byte ECC, see page below). One thing which is not very nice, in > order to fit the 60-byte ECC into the 64-byte OOB, I had to shorten > the BBT pattern and set it at the very beginning of the page. This > works fine, however this basically sets the page also to factory bad, > I'm not sure if this is ok? Otherwise, we also could use a BBT pattern > of length 1 (used by cafe_nand.c too). I guess that is a DT option? I wouldn't be an expert on this. So submitting it to the linux-mtd is good. I am also not sure if the HW ECC will work with 'sub-pages'. I think a college of your at Toradex submitted a patch to the u-boot. I am pretty sure that it could work with software ECC, but maybe disabling it is easiest. > What do you think? I would like to respin the NFC patch, with my > U-Boot changes and this change included... Please go ahead. Markus M is also using the fsl_nfc driver on a Freescale MPC5125 board, so it is probably good to copy your patches to him. At least, he can test on a BE platform. People also complained about JFFS and this version of the driver. I didn't investigate that. Thanks, Bill Pringlemeir.