On 22/09/2021 11:10, Wolfram Sang wrote: > This patch fixes 2 problems: > [1] The output warning logs and data loss when performing > mount/umount then remount the device with jffs2 format. > [2] The access width of SMWDR[0:1]/SMRDR[0:1] register is wrong. > > This is the sample warning logs when performing mount/umount then > remount the device with jffs2 format: > jffs2: jffs2_scan_inode_node(): CRC failed on node at 0x031c51d4: > Read 0x00034e00, calculated 0xadb272a7 > > The reason for issue [1] is that the writing data seems to > get messed up. > Data is only completed when the number of bytes is divisible by 4. > If you only have 3 bytes of data left to write, 1 garbage byte > is inserted after the end of the write stream. > If you only have 2 bytes of data left to write, 2 bytes of '00' > are added into the write stream. > If you only have 1 byte of data left to write, 2 bytes of '00' > are added into the write stream. 1 garbage byte is inserted after > the end of the write stream. > > To solve problem [1], data must be written continuously in serial > and the write stream ends when data is out. > > Following HW manual 62.2.15, access to SMWDR0 register should be > in the same size as the transfer size specified in the SPIDE[3:0] > bits in the manual mode enable setting register (SMENR). > Be sure to access from address 0. > > So, in 16-bit transfer (SPIDE[3:0]=b'1100), SMWDR0 should be > accessed by 16-bit width. > Similar to SMWDR1, SMDDR0/1 registers. > In current code, SMWDR0 register is accessed by regmap_write() > that only set up to do 32-bit width. Is this part something worth splitting to its own patch? > > To solve problem [2], data must be written 16-bit or 8-bit when > transferring 1-byte or 2-byte. > > Signed-off-by: Duc Nguyen <duc.nguyen.ub@xxxxxxxxxxx> > [wsa: refactored to use regmap only via reg_read/reg_write] > Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> > --- > > Hi, > > I could reproduce the issue by a simple: > > $ echo "Hello" > /dev/mtd10 > > The original BSP patch fixed the issue but mixed regmap-acces with > ioread/iowrite accesses. So, I refactored it to use custom regmap > accessors. This keeps the code more readable IMO. With this patch, my > custom test cases work as well as the JFFS2 remount mentioned in the > commit message. Tested on a Renesas Condor board (R-Car V3M) and a > Falcon board (R-Car V3U). I send this as RFC because this is my first > patch for the RPC code and hope for feedback. The BSP team has been > contacted as well for comments and testing. Nonetheless, this addresses > a serious issue which has caused broken boards because of writing to > unintended locations. So, I'd like to see this discussed and applied > soon if possible. > > Thanks everyone, > > Wolfram > > > drivers/memory/renesas-rpc-if.c | 113 ++++++++++++++++++++++---------- > include/memory/renesas-rpc-if.h | 1 + > 2 files changed, 79 insertions(+), 35 deletions(-) You sent the patch just slightly after this one: https://lore.kernel.org/lkml/20210922184830.29147-1-andrew_gabbasov@xxxxxxxxxx/ Are you solving similar problem? Best regards, Krzysztof
