[int13con] Create log partition only when CONSOLE_INT13 is enabled

Reduce the size of the USB disk image in the common case that
CONSOLE_INT13 is not enabled.

Originally-implemented-by: Romain Guyard <romain.guyard@mujin.co.jp>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/arch/x86/prefix/usbdisk.S b/src/arch/x86/prefix/usbdisk.S
index 830f3774c256390b479379bf784331d36974621b..977de6dd63bea641dc776838b5baef6f439a7fc0 100644 (file)
--- a/src/arch/x86/prefix/usbdisk.S
+++ b/src/arch/x86/prefix/usbdisk.S
@@ -1,5 +1,7 @@
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
 
+#include <config/console.h>
+
        .text
        .arch i386
        .section ".prefix", "awx", @progbits
@@ -13,10 +15,17 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
 #define SECTORS 32
 #define CYLADDR(cyl) ((((cyl) * HEADS + (((cyl) == 0) & 1)) * SECTORS) * 512)
 
+#ifdef CONSOLE_INT13
+#define LOGPART 1
 #define LOGSTART 0
 #define LOGCOUNT 1
 #define BOOTSTART 1
 #define BOOTCOUNT 2
+#else /* CONSOLE_INT13 */
+#define LOGPART 0
+#define BOOTSTART 0
+#define BOOTCOUNT 2
+#endif /* CONSOLE_INT13 */
 
        /* Construct a C/H/S address */
        .macro  chs cylinder, head, sector
@@ -44,8 +53,14 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
        .org 446
        .space 16
        .space 16
+
        /* Partition 3: log partition (for CONSOLE_INT13) */
+       .if LOGPART
        partition 0x00, 0xe0, LOGSTART, LOGCOUNT
+       .else
+       .space 16
+       .endif
+
        /* Partition 4: boot partition */
        partition 0x80, 0xeb, BOOTSTART, BOOTCOUNT
 
@@ -54,8 +69,10 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
        .byte 0x55, 0xaa
 
 /* Skip to start of log partition */
+       .if LOGPART
        .org CYLADDR(LOGSTART)
        .ascii "iPXE LOG\n\n"
+       .endif
 
 /* Skip to start of boot partition */
        .org CYLADDR(BOOTSTART)