On 03/05/13 17:59, David Woodhouse wrote:> On Tue, 2013-03-05 at 17:03 +0100, Paolo
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. (git.seabios.org
(126.96.36.199) seems to be down ATM, so I can only check at f465e1ec.)
623 ljmpw $SEG_BIOS, $entry_post
538 cmpl $0, %cs:HaveRunPost // Check for resume/reboot
539 jnz entry_resume
540 ENTRY_INTO32 _cfunc32flat_handle_post // Normal entry point
248 // Call handler.
249 jmp handle_resume
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].