Il 05/03/2013 20:12, Laszlo Ersek ha scritto: > On 03/05/13 17:59, David Woodhouse wrote:> On Tue, 2013-03-05 at 17:03 +0100, > Paolo Bonzini wrote: >>> Resuming from suspend-to-RAM should not reset all devices. Only the >>> CPU should get a reset signal. >> >> Hm... on reflection, I don't actually know if this is true. >> >> Perhaps we *should* reset all devices. After all, in a real machine >> they'll all have been turned off and the RAM will have been in >> self-refresh. Surely they have to be reset? >> >> So maybe we should *let* the i440FX PAM registers get reset to point to >> ROM. And fix the firmware to *cope* with that, check to see if the >> shadow RAM already holds an image of a started-up firmware with the >> correct checksum, and jump back to it. >> >> That is: perhaps it's a *SeaBIOS* bug that suspend/resume doesn't work >> if the PAM configuration is reset? > > I think it is indeed a problem with SeaBIOS. Open romlayout.S: [...] > > It checks the CMOS only after looking at HaveRunPost. The value of > HaveRunPost depends on the PAM settings. It's always 0 in ROM, in which > case we continue at handle_post() [src/post.c].
Actually, Peter explained that it is okay. S3 doesn't clear the PAM configuration, but S4 does. The PAM registers are attached to the same power line as the RAM. Paolo
