Hi, Ezequiel Garcia <ezequiel.garcia@xxxxxxxxxxxxxxxxxx> writes: > (Fixing Cc list: dropping devicetree guys, and adding Brian and MTD instead) > > On 05 Sep 04:23 PM, klightspeed@xxxxxxxxxxxxxxxx wrote: >> The bootloader on the Netgear ReadyNAS RN102 uses Hardware BCH ECC >> (strength = 4), while the pxa3xx NAND driver by default uses >> Hamming ECC (strength = 1). >> > > Hm, I guess the device (Hynix H27U1G8F2BTR) does not support ONFI, > and the kernel is just taking the legacy ECC. The flash specs makes no > mention to ONFI, so probably no ONFI here. > >> This patch changes the ECC mode on these machines to match that >> of the bootloader and of the stock firmware, so that for example >> updating the kernel is possible without requiring a serial >> connection. >> >> This patch depends on commit 5b3e507 (mtd: nand: pxa3xx: Use ECC >> strength and step size devicetree binding) >> >> Signed-off-by: Ben Peddell <klightspeed@xxxxxxxxxxxxxxxx> > > Looks good to me, since Arnaud reports this is the correct ECC scheme: > http://natisbad.org/NAS2/index.html#hw-nand > > Acked-by: Ezequiel Garcia <ezequiel.garcia@xxxxxxxxxxxxxxxxxx> > > Thanks for the fix, w/o the patch, you can write data to the flash using userland tools from mtd-utils package (flash_erase and nandwrite); data can then be read again using userland tools (say using dd). But - as reported by Ben - if you nandwrite an uImage from userland, here is what you indeed get from u-boot when you try and boot that image: root@humble:~# flash_erase /dev/mtd2 0 0 Erasing 128 Kibyte @ 5e0000 -- 100 % complete root@humble:~# nandwrite -p /dev/mtd2 /tmp/uImage-3.16.1.rn102 Writing data to block 0 at offset 0x0 Writing data to block 1 at offset 0x20000 Writing data to block 2 at offset 0x40000 Writing data to block 3 at offset 0x60000 Writing data to block 4 at offset 0x80000 ... reboot ... Marvell>> nand read 0x1200000 0x200000 0x600000 NAND read: device 0 offset 0x200000, size 0x600000 6291456 bytes read: OK Marvell>> bootm 0x1200000 ## Booting kernel from Legacy Image at 01200000 ... Image Name: Linux-3.16.1.rn102 Created: 2014-08-14 13:33:46 UTC Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 4423998 Bytes = 4.2 MB Load Address: 00008000 Entry Point: 00008000 Verifying Checksum ... Bad Data CRC ERROR: can't get kernel image! Now, w/ the patch submitted by Ben, here is what you get: With the patch applied, this indeed works has ## Booting kernel from Legacy Image at 01200000 ... Image Name: Linux-3.16.1.rn102 Created: 2014-09-05 20:25:34 UTC Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 4424067 Bytes = 4.2 MB Load Address: 00008000 Entry Point: 00008000 Verifying Checksum ... OK Loading Kernel Image ... OK OK Starting kernel ... i.e. it works. So, thanks for reporting this, Ben. I must confess I got used to update my kernels from u-boot and did not take enough attention to that aspect when I updated the .dts to add access to NAND after Ezequiel wrote the NAND driver. I will take a look at RN104 and RN2120 to check if something similar is needed for those two. FWIW, you can add my: Tested-by: Arnaud Ebalard <arno@xxxxxxxxxxxx> Additionally, Ezequiel, would anything prevent pushing the patch to stable team (nand entry in .dts was added in 3.14): Fixes: 92beaccd8b49 ("ARM: mvebu: Enable NAND controller in ReadyNAS 102 .dts file") Cheers, a+ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
