From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from aa011-1msr.fastwebnet.it ([62.101.93.131]) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1RBnNK-0004Ay-Um for linux-mtd@lists.infradead.org; Thu, 06 Oct 2011 12:48:35 +0000 Subject: Re: cfi_cmdset_0002.c SST39VF3201B issue From: Fabio Giovagnini To: angelo In-Reply-To: <4E8D9F14.4090108@gmail.com> References: <4E8D9F14.4090108@gmail.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 06 Oct 2011 14:48:33 +0200 Message-ID: <1317905313.4526.9.camel@AURIO02> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Cc: "linux-mtd@lists.infradead.org" , uClinux development list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , I would try to keep the 4kBi blocks. regards Il giorno gio, 06/10/2011 alle 14.29 +0200, angelo ha scritto: > Dear all, > > like me some other users had issues with this chip and jffs2. > > From time to time users asks why they get errors trying to use jffs2 > with this chip. > > This chip, from the datasheet, allows to erase 4KB "sectors" or 64KB > "blocks", replying to cfi queries with a "setcor" erase size and a > "block" erase size. > > I can be wrong of course, but this is what i figured out: > > > 1) fixup decision > > Someone of you decided to fix up this SST39VF3201 in this way: > > static void fixup_old_sst_eraseregion(struct mtd_info *mtd) > { > struct map_info *map = mtd->priv; > struct cfi_private *cfi = map->fldrv_priv; > > /* > * These flashes report two seperate eraseblock regions based on the > * sector_erase-size and block_erase-size, although they both > operate on the > * same memory. This is not allowed according to CFI, so we just > pick the > * sector_erase-size. > */ > cfi->cfiq->NumEraseRegions = 1; > } > > Of course, in this way, deciding 0x1000 (sector-size) is the one to use, > jffs2 cannot be used safely, since > minimal data block is 4Kb + some hdr bytes. Wasn't better fixup to > "block" size (64K) ? > > > 2) after fixup decision, when jffs2 asks to erase a block to > cfi_cmdset_0002.c, cfi driver seems to erase wrongly a 64K block. > This is what happen in detail: > jffs erase.c, to erase a block does: mtd->erase(), with a len > mtd->erasesize (4KB). > mtd->erase() is calls cfi_amdstd_erase_varsize ... > finally, do_erase_oneblock is called, where: > > cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, > cfi->device_type, NULL); > cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, > cfi->device_type, NULL); > cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, > cfi->device_type, NULL); > cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, > cfi->device_type, NULL); > cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, > cfi->device_type, NULL); > map_write(map, CMD(0x30), adr); > > but this chip uses 0x30 cmd to erase a 64 KB block, and 0x50 to erase a > sector. > > Please let me know if i am in the right direction, so i can think about > a patch that allows > jffs2 to be used with native hw 64KB block erasesize. > > Regards > Angelo Dureghello > > > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ -- Fabio Giovagnini Aurion s.r.l. P.iva 00885711200 cell. +39.335.8350919 Tel. +39.051.594.78.24 Fax. +39 051.082.14.49 skype: aurion.giovagnini