-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Carl-Daniel Hailfinger wrote: > On 12.01.2008 01:18, Rudolf Marek wrote: >> Imho you must copy the data from CAR, because when it is OFF, no >> writeback is >> done to memory: (from BKDG) >> >> Temporary data stored in the cache during boot cannot be written back >> to DRAM >> after enabling the >> DRAM controller using a CLFLUSH or WBINVB instruction. The cache should be >> invalidated after the DRAM controller is initialized with an INVD >> instruction. > > OK, then we simply copy the whole CAR area to some backup memory > location, disable CAR, then INVD and copy everything back to the > original location. That way, moving the stack with all of its nasty side > effects will not happen. > >> The later is imho not done in LB I think. Maybe needs fix? > > I have to reread the v2 code. Almost all BIOS code I write nowadays is > either for code shared between v2 and v3 or for v3 only.
Ok, I tried to research this yesterday but failed to find it. > >> Btw please design it to be suspend-to-ram friendly ;) > > Will do. Is there any specific part of the source that lists your > requirements for suspend-to-RAM? IIRC resume-from-RAM enables CAR, gets > RAM out of self-refresh, then jumps back to the OS. Writing to arbitrary > RAM locations has to be avoided with suspend-to-RAM. Yes or at least now please write to 1MB - TOPK region as it is done now in v2. So the CAR is written directly bellow to TOPK. I think for S3 I will need to define LOWK too. -maybe just _RAMBASE But lets assume now that 1MB-TOPK memory can be used. Please try to avoid writings anywhere in bellow 1MB as possible (to RAM, CAR location is "dont care" for me). I think to run S3 from unpatched kernel I still need to fix Secondary.S boot plus my reset realmode routine. I think I will put it directly to first 4KB of memory, which will be later overwritten by tables anyway. So far, I would prefer if LB uses mem like this: 0-4KB (lowmem data area) _RAMBASE - TOPK 0xf000 BIOS segment for DSDT etc This memory should be reserved in e820 _RAMBASE-TOPK plus we can use ACPI memory hotplug to reclaim this memory back once linux is restored ;) (yeah my know idea ) So haveing _RAMBASE sitting at 1MB as default would be cool too, eliminates the stack computations for 1MB for APs too. Thanks, Rudolf > > Regards, > Carl-Daniel -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHiJpb3J9wPJqZRNURAuQtAKCavij93Vg0f8TekFRdyLMshVV0yACeLLGl JBXCF65n+hlisp2eFool7tQ= =BfuB -----END PGP SIGNATURE----- -- linuxbios mailing list linuxbios@linuxbios.org http://www.linuxbios.org/mailman/listinfo/linuxbios
