From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4F3CE2D4.4070506@freebox.fr> Date: Thu, 16 Feb 2012 12:04:52 +0100 From: Florian Fainelli MIME-Version: 1.0 To: Huang Shijie Subject: Re: [PATCH] mtd: fix the wrong check condition References: <1329302008-10228-1-git-send-email-b32955@freescale.com> <4F3C712A.5060406@gmail.com> <4F3C7433.5030306@freescale.com> In-Reply-To: <4F3C7433.5030306@freescale.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Brian Norris , linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Matthieu Castet List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, On 02/16/12 04:12, Huang Shijie wrote: > Hi, >> (Add Florian and Matthieu) >> >> On 2/15/2012 2:33 AM, Huang Shijie wrote: >>> If we use `||` check condition, many NAND chips which are not >>> ONFI nands have to do the ONFI detection. >> >> Running the ONFI detection on non-ONFI NAND should not, ideally, be a >> problem. They should fail one or both tests included in the routine: >> the 'O N F I' string check or the CRC calculation. > NO. Can you please post the dump of the ONFI page as read by your controller? Is the CRC check passing? The ONFI crc function is made so that a page full of zeroes or 0xff won't generate a respectively 0 or ff checksum, so we should catch this during the CRC check. > > I have Hynix nand in my hand: H27UBG8T2A (page size :8192, oob:448). > It is not an ONFI nand. See the datasheet in the attachment. > But it accidentally can pass the ONFI detection, and get the result : > page size 4192, oob:96. This is a wrong result. I have already seen a Hynix chip answering to the READID command too, and this was highly confusing our bootloader, however, I suppose that we should be able to circumvent this issue anyway. > > > > >> >>> Use `&&` here to detect the ONFI NAND when we can not find any type >>> in the nand_flash_ids. >> >> There are many chips whose ID might be in the NAND table but for which >> it is preferable (or even required) to check by ONFI for one reason or >> another. For instance, some ONFI chips might use odd-sized OOB that >> isn't in the ID decoding algorithm. >> > This nand is 32Gb, but we can not parse it out from the id. > I ever want to add a new database which use the all the 8/6 bytes id as > key. > It seems it's time to change it now. You have said that already, but we have yet to see patches for this, I guess if you can post your database patch that will be easier to comment on. -- Florian