Stefan Roese <s...@denx.de> schrieb am Mo., 6. Aug. 2018, 17:23: > Hi Simon, > > On 06.08.2018 17:15, Simon Goldschmidt wrote: > > > > > > Stefan Roese <s...@denx.de <mailto:s...@denx.de>> schrieb am Mo., 6. Aug. > > 2018, 16:34: > > > > Some SPI NOR chips only support 4-byte mode addressing. Here the > default > > 3-byte mode does not work and leads to incorrect accesses. Setting > this > > option enables the use of such SPI NOR chips, that only support this > > 4-byte mode. > > > > > > I think it would make more sense to enable 4-byte mode or 4-byte opcodes > > on all chips with more than 16 mbyte rather than having to select at > > compile time. > > We need to be careful here. As setting the chip into 4-byte mode > unconditionally (for bigger devices) will very likely cause boot > problems with internal bootROMs expecting 3-byte mode. >
I have a similar problem on socfpga where Linux 4.9 sets the chip into 4-byte mode and SPL cannot use it on warm reboot. However, the bootROM does not run on warm reboot on this platform. I just think it would be good to solve these related problems in a more generic way. Simon > As noted in the commit message, this is a very special case, where > the SPI NOR only supports 4-byte opcodes / mode. > > Another idea would be to check the 3-byte / 4-byte mode of the SPI > NOR device upon SPI NOR driver loading and use the selected mode > accordingly. This could be done without compile time options but > it would not help in general for users with bigger SPI NOR devices > that support both modes. > > Thanks, > Stefan > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
