On Mon, 6 Apr 2020 at 07:18, Chuanhong Guo wrote: > > Hi Robert! > > On Sat, Apr 4, 2020 at 9:01 PM Chuanhong Guo wrote: > > "line over 80 characters" warning produced by checkpatch.pl isn't > > fixed because I think a revert commit should bring a file back to > > what it was before. > > I don't have a w25q256jv available and can't compare SFDP table > > to create a fix similar to mx25l25635 one. > > I just tried and unable to dump SFDP on my W25Q256FV, > probably because my chip is too old to have one. > Could you check if your W25Q256JV has this and dump it? > Just add some prints in spi_nor_read_sfdp. > If a 4-byte address instruction table is present, current kernel > should be able to discover 4B_OPCODES support automatically. > Even if that's not the case we may still be able to distinguish > W25Q256FV and W25Q256JV using SFDP table. It appears that W25Q256JV has an SFDP table and in it advertises 3B or 4B modes. > > [ 1.957903] spi_qup 78b5000.spi: IN:block:16, fifo:64, OUT:block:16, fifo:64 > [ 1.962185] SFDP advertises 3B or 4B > [ 1.977393] spi-nor spi0.0: w25q256 (32768 Kbytes) > I have used the attached patch to check what does the SFDP DWORD 1 advertises. If FV version has or does not advertise 4B support than that can be used to differentiate them. Can you apply this patch and check what the FV version advertises as I don't have a device using that revision. FV version also should have SFDP as datasheet for it clearly advertises is. Best regards Robert > > -- > Regards, > Chuanhong Guo