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David Woodhouse ea1b7a0733 xen: require Xen info structure at 0x1000 to detect Xen When running under Xen, hvmloader places a table at 0x1000 with the e820 information and BIOS tables. If this isn't present, SeaBIOS will currently panic. We now have support for running Xen guests natively in QEMU/KVM, which boots SeaBIOS directly instead of via hvmloader, and does not provide the same structure. As it happens, this doesn't matter on first boot. because although we set PlatformRunningOn to PF_QEMU\|PF_XEN, reading it back again still gives zero. Presumably because in true Xen, this is all already RAM. But in QEMU with a faithfully-emulated PAM config in the host bridge, it's still in ROM mode at this point so we don't see what we've just written. On reboot, however, the region is set to RAM mode and we do see the updated value of PlatformRunningOn, do manage to remember that we've detected Xen in CPUID, and hit the panic. It's not trivial to detect QEMU vs. real Xen at the time xen_preinit() runs, because it's so early. We can't even make a XENVER_extraversion hypercall to look for hints, because we haven't set up the hypercall page (and don't have an allocator to give us a page in which to do so). So just make Xen detection contingent on the info structure being present. If it wasn't, we were going to panic anyway. That leaves us taking the standard QEMU init path for Xen guests in native QEMU, which is just fine. Untested on actual Xen but ObviouslyCorrect™. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>		3 days ago
docs	docs: Note v1.16.0 release	11 months ago
scripts	scripts: Remove python23compat.py	1 year ago
src	xen: require Xen info structure at 0x1000 to detect Xen	3 days ago
vgasrc	vgasrc: Don't use VAR16 in header files to fix gcc warning	1 year ago
.gitignore	Start using Kconfig to configure SeaBIOS settings.	12 years ago
COPYING	Initial checkin.	15 years ago
COPYING.LESSER	Change license from GPLv3 to LGPLv3.	14 years ago
Makefile	Add implementations for sha256, sha384, and sha512	2 years ago
README	Simplify README files - point to online documentation instead	8 years ago

README

Welcome to the SeaBIOS project!  This project implements an X86 legacy

bios that is built with standard GNU tools.



Please see build and developer information at:



  http://seabios.org/Developer_Documentation



For the impatient, SeaBIOS is built for QEMU and tested on QEMU with:



  make

  qemu -bios out/bios.bin



SeaBIOS can be configured with kconfig.  To change the default

configuration one can run "make menuconfig" prior to running "make".



For other types of builds, and for more detailed developer

documentation, please see the online documentation listed above.