vgabios: Add debug message if x86emu leal check triggers.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

diff --git a/vgasrc/vgaentry.S b/vgasrc/vgaentry.S
index 6e31c4edc2ce2f7f7d63cbb11fca5fb304a95b06..11197f1a0fc3b2855e478da6a2476bf29501f7d3 100644 (file)
--- a/vgasrc/vgaentry.S
+++ b/vgasrc/vgaentry.S
@@ -47,7 +47,17 @@ _rom_header_signature:
 
         // Force a fault if found to be running on broken x86emu versions.
         DECLFUNC x86emu_fault
+msg:    .ascii "SeaVGABIOS: x86emu leal trap!\n"
 x86emu_fault:
+#if CONFIG_DEBUG_IO
+        movw %cs:DebugOutputPort, %dx
+        movw $msg, %si
+1:      movb %cs:(%si), %al
+        outb %al, (%dx)
+        incw %si
+        cmpw $x86emu_fault, %si
+        jl 1b
+#endif
 1:      hlt
         jmp 1b