i386: move boot

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 125 insertions, 0 deletions

diff --git a/arch/x86/boot/video-bios.c b/arch/x86/boot/video-bios.c
new file mode 100644
index 000000000000..68e65d95cdfd
--- /dev/null
+++ b/arch/x86/boot/video-bios.c
@@ -0,0 +1,125 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *   Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ *   This file is part of the Linux kernel, and is made available under
+ *   the terms of the GNU General Public License version 2.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * arch/i386/boot/video-bios.c
+ *
+ * Standard video BIOS modes
+ *
+ * We have two options for this; silent and scanned.
+ */
+
+#include "boot.h"
+#include "video.h"
+
+__videocard video_bios;
+
+/* Set a conventional BIOS mode */
+static int set_bios_mode(u8 mode);
+
+static int bios_set_mode(struct mode_info *mi)
+{
+        return set_bios_mode(mi->mode - VIDEO_FIRST_BIOS);
+}
+
+static int set_bios_mode(u8 mode)
+{
+        u16 ax;
+        u8 new_mode;
+
+        ax = mode;              /* AH=0x00 Set Video Mode */
+        asm volatile(INT10
+                     : "+a" (ax)
+                     : : "ebx", "ecx", "edx", "esi", "edi");
+
+        ax = 0x0f00;            /* Get Current Video Mode */
+        asm volatile(INT10
+                     : "+a" (ax)
+                     : : "ebx", "ecx", "edx", "esi", "edi");
+
+        do_restore = 1;         /* Assume video contents were lost */
+        new_mode = ax & 0x7f;   /* Not all BIOSes are clean with the top bit */
+
+        if (new_mode == mode)
+                return 0;       /* Mode change OK */
+
+        if (new_mode != boot_params.screen_info.orig_video_mode) {
+                /* Mode setting failed, but we didn't end up where we
+                   started.  That's bad.  Try to revert to the original
+                   video mode. */
+                ax = boot_params.screen_info.orig_video_mode;
+                asm volatile(INT10
+                             : "+a" (ax)
+                             : : "ebx", "ecx", "edx", "esi", "edi");
+        }
+        return -1;
+}
+
+static int bios_probe(void)
+{
+        u8 mode;
+        u8 saved_mode = boot_params.screen_info.orig_video_mode;
+        u16 crtc;
+        struct mode_info *mi;
+        int nmodes = 0;
+
+        if (adapter != ADAPTER_EGA && adapter != ADAPTER_VGA)
+                return 0;
+
+        set_fs(0);
+        crtc = vga_crtc();
+
+        video_bios.modes = GET_HEAP(struct mode_info, 0);
+
+        for (mode = 0x14; mode <= 0x7f; mode++) {
+                if (heap_free() < sizeof(struct mode_info))
+                        break;
+
+                if (mode_defined(VIDEO_FIRST_BIOS+mode))
+                        continue;
+
+                if (set_bios_mode(mode))
+                        continue;
+
+                /* Try to verify that it's a text mode. */
+
+                /* Attribute Controller: make graphics controller disabled */
+                if (in_idx(0x3c0, 0x10) & 0x01)
+                        continue;
+
+                /* Graphics Controller: verify Alpha addressing enabled */
+                if (in_idx(0x3ce, 0x06) & 0x01)
+                        continue;
+
+                /* CRTC cursor location low should be zero(?) */
+                if (in_idx(crtc, 0x0f))
+                        continue;
+
+                mi = GET_HEAP(struct mode_info, 1);
+                mi->mode = VIDEO_FIRST_BIOS+mode;
+                mi->x = rdfs16(0x44a);
+                mi->y = rdfs8(0x484)+1;
+                nmodes++;
+        }
+
+        set_bios_mode(saved_mode);
+
+        return nmodes;
+}
+
+__videocard video_bios =
+{
+        .card_name      = "BIOS (scanned)",
+        .probe          = bios_probe,
+        .set_mode       = bios_set_mode,
+        .unsafe         = 1,
+        .xmode_first    = VIDEO_FIRST_BIOS,
+        .xmode_n        = 0x80,
+};