On 09/26/18 06:44, Gerd Hoffmann wrote: > Hi, > >> Second, the v5 RFC doesn't actually address the alleged bus number >> shortage. IIUC, it supports a low number of ECAM ranges under 4GB, but >> those are (individually) limited in the bus number ranges they can >> accommodate (due to 32-bit address space shortage). So more or less the >> current approach just fragments the bus number space we already have, to >> multiple domains. > > Havn't looked at the qemu side too close yet, but as I understand things > the firmware programs the ECAM location (simliar to the q35 mmconf bar), > and this is just a limitation of the current seabios patch. > > So, no, *that* part wouldn't be messy in ovmf, you can simply place the > ECAMs where you want.
Figuring out "wherever I want" is the problem. It's not simple. The 64-bit MMIO aperture (for BAR allocation) can also be placed mostly "wherever the firmware wants", and that wasn't simple either. All these things end up depending on each other. https://bugzilla.redhat.com/show_bug.cgi?id=1353591#c8 ( The placement of the q35 MMCONF BAR was difficult too; I needed your help with the low RAM split that QEMU would choose. v1 discussion: http://mid.mail-archive.com/[email protected] v2 patch (ended up as commit 7b8fe63561b4): http://mid.mail-archive.com/[email protected] These things add up :( ) Laszlo _______________________________________________ SeaBIOS mailing list [email protected] https://mail.coreboot.org/mailman/listinfo/seabios
