[PATCH v4 1/2] ARM: socfpga: support suspend to ram
pavel at denx.de
Tue May 26 14:56:17 PDT 2015
> Thanks for the feedback.
> Yes I agree.
> One possibility is that I could add a suspend function to EDAC that
> always fails with a helpful message like "Suspend with EDAC not
> supported." If someone wants to suspend, they'll have to take the
> EDAC out of the device tree so its probe will bomb out. I'm not
> sure how normal it is to have suspend functions in the kernel
> that always fail, though.
"Interesting" solution, but better than config exclusion, I'd say.
> > > + /*
> > > + * This code assumes that the bootloader has already
> > > + * properly configured the sdram controller:
> > Which bootloaders can do that?
> Whatever bootloader is configuring the sdram controller for the
Ok, so direct question: will mainline u-boot 2015.04 configure the
> > > + * sdr.ctrlcfg.lowpwreq.selfrfshmask = 3
> > > + * sdr.ctrlcfg.lowpwrtiming.clkdisablecycles = 8
> > > + * sdr.ctrlcfg.dramtiming4.selfrfshexit = 512
> > Would it make sense to configure it in Linux?
> The bootloader is responsible for configuring the sdram
> controller with parameters appropriate for whatever vendor's DDR
> is on the board, so that's where this must go.
> Now I realize I should make this message more general, since it is
> true for the socfpga cyclone5 devkit, but may need to be adjusted
> for other boards.
Aha, ok, the comment really needs to be fixed.
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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