1 files changed, 86 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/com32/mboot/apm.c b/contrib/syslinux-4.02/com32/mboot/apm.c
new file mode 100644
index 0000000..3f48af7
--- /dev/null
+++ b/contrib/syslinux-4.02/com32/mboot/apm.c
@@ -0,0 +1,86 @@
+/* ----------------------------------------------------------------------- *
+ *
+ *   Copyright 2009 Intel Corporation; author: H. Peter Anvin
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ *   Boston MA 02110-1301, USA; either version 2 of the License, or
+ *   (at your option) any later version; incorporated herein by reference.
+ *
+ *   Based on code from the Linux kernel:
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *   Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ *   Original APM BIOS checking by Stephen Rothwell, May 1994
+ *   (sfr@canb.auug.org.au)
+ *
+ *   This file is part of the Linux kernel, and is made available under
+ *   the terms of the GNU General Public License version 2.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * apm.c
+ *
+ * APM information for Multiboot
+ */
+
+#include "mboot.h"
+#include <com32.h>
+
+void mboot_apm(void)
+{
+    static struct apm_info apm;
+    com32sys_t ireg, oreg;
+
+    memset(&ireg, 0, sizeof ireg);
+
+    ireg.eax.w[0] = 0x5300;
+    __intcall(0x15, &ireg, &oreg);
+
+    if (oreg.eflags.l & EFLAGS_CF)
+	return;			/* No APM BIOS */
+
+    if (oreg.ebx.w[0] != 0x504d)
+	return;			/* No "PM" signature */
+
+    if (!(oreg.ecx.w[0] & 0x02))
+	return;			/* 32 bits not supported */
+
+    /* Disconnect first, just in case */
+    ireg.eax.b[0] = 0x04;
+    __intcall(0x15, &ireg, &oreg);
+
+    /* 32-bit connect */
+    ireg.eax.b[0] = 0x03;
+    __intcall(0x15, &ireg, &oreg);
+
+    apm.cseg = oreg.eax.w[0];
+    apm.offset = oreg.ebx.l;
+    apm.cseg_16 = oreg.ecx.w[0];
+    apm.dseg_16 = oreg.edx.w[0];
+    apm.cseg_len = oreg.esi.w[0];
+    apm.cseg_16_len = oreg.esi.w[1];
+    apm.dseg_16_len = oreg.edi.w[0];
+
+    /* Redo the installation check as the 32-bit connect;
+       some BIOSes return different flags this way... */
+
+    ireg.eax.b[0] = 0x00;
+    __intcall(0x15, &ireg, &oreg);
+
+    if ((oreg.eflags.l & EFLAGS_CF) || (oreg.ebx.w[0] != 0x504d)) {
+	/* Failure with 32-bit connect, try to disconect and ignore */
+	ireg.eax.b[0] = 0x04;
+	__intcall(0x15, &ireg, NULL);
+	return;
+    }
+
+    apm.version = oreg.eax.w[0];
+
+    mbinfo.apm_table = map_data(&apm, sizeof apm, 4, false);
+    if (mbinfo.apm_table)
+	mbinfo.flags |= MB_INFO_APM_TABLE;
+}