Date: Mon, 03 Sep 2012 13:10:40 +0200 From: =?ISO-8859-1?Q?Gustau_P=E9rez_i_Querol?= <gperez@entel.upc.edu> To: emulation@freebsd.org Subject: Fix ich9 bios to correctly configure pci bridge1 and pci bridge2 Message-ID: <50449030.1010206@entel.upc.edu>
next in thread | raw e-mail | index | archive | help
This is a multi-part message in MIME format. --------------000607020103010207010304 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit The upcoming 4.2.0 release of virtualbox allows to plug more than 8 network adapter to a guest. When testing that kind of setup I noticed FreeBSD (stable or head, it doesn't matter) is unable to map more than 8 cards. It appears that the ninth (and so on) get connected to the pci bus 1. The output of a guest FreeBSD machine shows this: ************* pcib1: <PCI-PCI bridge> at device 24.0 on pci0 pcib1: domain 0 pcib1: secondary bus 1 pcib1: subordinate bus 2 pcib1: no prefetched decode pcib1: Subtractively decoded bridge. pci1: <PCI bus> on pcib1 pci1: domain=0, physical bus=1 pcib2: <PCI-PCI bridge> at device 25.0 on pci0 pcib0: allocated type 4 (0xe000-0xefff) for rid 1c of pcib2 pcib0: allocated type 3 (0xf0a00000-0xf0afffff) for rid 20 of pcib2 pcib2: domain 0 pcib2: secondary bus 2 pcib2: subordinate bus 3 pcib2: I/O decode 0xe000-0xefff pcib2: memory decode 0xf0a00000-0xf0afffff pcib2: no prefetched decode pcib2: Subtractively decoded bridge. pci2: <PCI bus> on pcib2 pci2: domain=0, physical bus=2 ********************* The topology the developers of vbox try to build is this: ----------------------------------------------------------- pci bus 0 | | ___ |______ _____|____ | | | | | Bridge1 | | Bridge2 | |_________| |_________| | | ----------- pci bus 1 ------------ pci bus 2 The problem is that the pci bridge1 connects the bus0 to the bus1 and thus the primary bus would 0; the secondary would the 1 because the bus 1 doesn't connect any other bus through any other bridge then its subordinate must be also 1. The pci bridge1 connects the pci bus 0 with the pci bus 2; the primary must be 0 and the secondary and subordinate must be 2: The vbox programmers set the subordinate bus of bridge1 to 2 and the subordinate of bridge2 to 3 (which is incorrect). At pci_pci.c we can add quirks to circumvent this (we can't change real hardware) but in this case we can change the hardware. I'm attaching the patch that changes the behavior of vbox. The output of FreeBSD virtual machine with the modified 'hardware' is this: ************* pcib1: <PCI-PCI bridge> at device 24.0 on pci0 pcib1: domain 0 pcib1: secondary bus 1 pcib1: subordinate bus 1 pcib1: no prefetched decode pcib1: Subtractively decoded bridge. pci1: <PCI bus> on pcib1 pci1: domain=0, physical bus=1 pcib2: <PCI-PCI bridge> at device 25.0 on pci0 pcib0: allocated type 4 (0xe000-0xefff) for rid 1c of pcib2 pcib0: allocated type 3 (0xf0a00000-0xf0afffff) for rid 20 of pcib2 pcib2: domain 0 pcib2: secondary bus 2 pcib2: subordinate bus 2 pcib2: I/O decode 0xe000-0xefff pcib2: memory decode 0xf0a00000-0xf0afffff pcib2: no prefetched decode pcib2: Subtractively decoded bridge. pci2: <PCI bus> on pcib2 pci2: domain=0, physical bus=2 ********************* Which is what should be according to the simple topology of the buses and bridges. It works as it should. I hope I did not say anything wrong. Best, Gustau -- --------------------------------------------------------------------------- Prou top-posting : http://ca.wikipedia.org/wiki/Top-posting Stop top-posting : http://en.wikipedia.org/wiki/Posting_style O O O Gustau Pérez i Querol O O O Departament d'Enginyeria Telemàtica O O O Universitat Politècnica de Catalunya Edifici C3 - Despatx S101-B UPC Campus Nord UPC C/ Jordi Girona, 1-3 08034 - Barcelona --------------000607020103010207010304--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?50449030.1010206>