Stefan Roese <s...@denx.de> schrieb am Mo., 6. Aug. 2018, 17:36: > On 06.08.2018 17:33, Simon Goldschmidt wrote: > > > > > > Stefan Roese <s...@denx.de <mailto:s...@denx.de>> schrieb am Mo., 6. Aug. > > 2018, 17:29: > > > > > > > > On 06.08.2018 17:27, Simon Goldschmidt wrote: > > > > > > > > > Stefan Roese <s...@denx.de <mailto:s...@denx.de> <mailto:s...@denx.de > > <mailto: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> > > <mailto:s...@denx.de <mailto:s...@denx.de>> <mailto:s...@denx.de > > <mailto:s...@denx.de> > > > <mailto: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. > > > > So in your "warm reboot" case, my option b) below would help, right? > > > > > > Yes, I guess it would. > > > > An even better idea would be to use stateless 4-byte opcodes. That's > > what Linux does in more recent versions. But that would be a larger > > patch, I guess. And with Jagan's bigger rework in his queue, I can't > > tell if this is a good time to do so. > > Yes, this is definitely out of scope for me, reworking this 4-byte > support to this stateless version.
Right. For me too. Sorry. But if we agree that the > option b) is helpful and harmless (which I think it is), then I > can rework this patch and re-send a version which should also work > for you - as described below. > That would be cool. I'd test this on my socrates board. Thanks, Simon > > > > b) > > 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 > > > > > Thanks, > Stefan > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
