Akio Takebe
2008-Dec-26 04:46 UTC
[Xen-devel] [Patch] Expand shadow memory area for using option ROM
Hi, This patch expands shadow memory of guest BIOS. Currently the shadow memory is 0xc0000 - 0xdffff. It is used by VGA, gPXE, option ROM, but the size of these ROMs is around 40k->64k, so the area is not enough. This patch is: - replace e820 table from 0xe0000 to 0xeb000. - expand shadowr from 0xc0000-0xdffff to 0xc0000-0xe8fff. - fix scan size of VGA BIOS. after this patch, BIOS map is below. BIOS map: c0000-c8fff: VGA BIOS c9000-d57ff: Etherboot ROM d5800-e0fff: PCI Option ROMs e9000-e919c: SMBIOS tables f0000-fffff: Main BIOS Signed-off-by: Akio Takebe <takebe_akio@jp.fujitsu.com> Ref: http://lists.xensource.com/archives/html/xen-devel/2008-12/msg00835.html Best Regards, Akio Takebe _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2008-Dec-29 14:27 UTC
Re: [Xen-devel] [Patch] Expand shadow memory area for using option ROM
On 26/12/2008 04:46, "Akio Takebe" <takebe_akio@jp.fujitsu.com> wrote:> This patch is: > - replace e820 table from 0xe0000 to 0xeb000. > - expand shadowr from 0xc0000-0xdffff to 0xc0000-0xe8fff. > - fix scan size of VGA BIOS. > > after this patch, BIOS map is below. > BIOS map: > c0000-c8fff: VGA BIOS > c9000-d57ff: Etherboot ROM > d5800-e0fff: PCI Option ROMs > e9000-e919c: SMBIOS tables > f0000-fffff: Main BIOSComments: 1. Why does the VGA BIOS ''scan size'' need to be fixed? What''s wrong with scanning only up to 0xc8000 for it, and letting option ROMs continue to reside from 0xc8000? Indeed, won''t the VGABIOS always be at 0xc0000, so we could actually only probe that address for it, and let option ROMs load as low as 0xc0800? 2. It''d be nice to give E820_PHYSICAL_ADDRESS a definition in config.h and then use that instead of hardcoding the address throughout rombios.c. -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Akio Takebe
2009-Jan-05 09:33 UTC
Re: [Xen-devel] [Patch] Expand shadow memory area for using option ROM
Keir Fraser wrote> On 26/12/2008 04:46, "Akio Takebe" <takebe_akio@jp.fujitsu.com> wrote: > >> This patch is: >> - replace e820 table from 0xe0000 to 0xeb000. >> - expand shadowr from 0xc0000-0xdffff to 0xc0000-0xe8fff. >> - fix scan size of VGA BIOS. >> >> after this patch, BIOS map is below. >> BIOS map: >> c0000-c8fff: VGA BIOS >> c9000-d57ff: Etherboot ROM >> d5800-e0fff: PCI Option ROMs >> e9000-e919c: SMBIOS tables >> f0000-fffff: Main BIOS > > Comments: > > 1. Why does the VGA BIOS ''scan size'' need to be fixed? What''s wrong with > scanning only up to 0xc8000 for it, and letting option ROMs continue to > reside from 0xc8000? Indeed, won''t the VGABIOS always be at 0xc0000, so we > could actually only probe that address for it, and let option ROMs load as > low as 0xc0800?Because the current VGA BIOS uses 0xc0000-0xc8fff from the following log. I want just to avoid the unnecessary scanning. (XEN) HVM1: BIOS map: (XEN) HVM1: c0000-c8fff: VGA BIOS (XEN) HVM1: c9000-d57ff: Etherboot ROM (XEN) HVM1: e9000-e919c: SMBIOS tables (XEN) HVM1: f0000-fffff: Main BIOS I think rombios works fine if we drop the part of the patch.> > 2. It''d be nice to give E820_PHYSICAL_ADDRESS a definition in config.h and > then use that instead of hardcoding the address throughout rombios.c. >I''ll try it. Best Regards, Akio Takebe _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel