[bios] Use INT 16,11 instead of INT 16,01 to check for keystrokes

INT 16,01 will discard some extended keystrokes on some BIOSes, making
it impossible for iPXE to detect keypresses such as F12.  Fix by using
INT 16,11 instead.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/arch/i386/firmware/pcbios/bios_console.c b/src/arch/i386/firmware/pcbios/bios_console.c
index 0720cd76de09604a9543e9603f5a47126a6ad185..55ab21bbb818d9022fdc523f7f7c49ce750a7713 100644 (file)
--- a/src/arch/i386/firmware/pcbios/bios_console.c
+++ b/src/arch/i386/firmware/pcbios/bios_console.c
@@ -286,7 +286,7 @@ static int bios_iskey ( void ) {
                                           "popw %w0\n\t"
                                           "cli\n\t" )
                               : "=r" ( flags ), "=a" ( discard_a )
-                              : "a" ( 0x0100 ) );
+                              : "a" ( 0x1100 ) );
        return ( ! ( flags & ZF ) );
 }