On 03/05/13 20:25, Paolo Bonzini wrote: > 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.
Ah, you expect me to understand that "memory controller configuration" is a superset of the PAM registers :) Laszlo
