1 files changed, 173 insertions, 0 deletions

diff --git a/arch/x86/boot/video-mode.c b/arch/x86/boot/video-mode.c
new file mode 100644
index 000000000000..748e8d06290a
--- /dev/null
+++ b/arch/x86/boot/video-mode.c
@@ -0,0 +1,173 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *   Copyright 2007-2008 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-mode.c
+ *
+ * Set the video mode.  This is separated out into a different
+ * file in order to be shared with the ACPI wakeup code.
+ */
+
+#include "boot.h"
+#include "video.h"
+#include "vesa.h"
+
+/*
+ * Common variables
+ */
+int adapter;                    /* 0=CGA/MDA/HGC, 1=EGA, 2=VGA+ */
+u16 video_segment;
+int force_x, force_y;   /* Don't query the BIOS for cols/rows */
+
+int do_restore;         /* Screen contents changed during mode flip */
+int graphic_mode;       /* Graphic mode with linear frame buffer */
+
+/* Probe the video drivers and have them generate their mode lists. */
+void probe_cards(int unsafe)
+{
+        struct card_info *card;
+        static u8 probed[2];
+
+        if (probed[unsafe])
+                return;
+
+        probed[unsafe] = 1;
+
+        for (card = video_cards; card < video_cards_end; card++) {
+                if (card->unsafe == unsafe) {
+                        if (card->probe)
+                                card->nmodes = card->probe();
+                        else
+                                card->nmodes = 0;
+                }
+        }
+}
+
+/* Test if a mode is defined */
+int mode_defined(u16 mode)
+{
+        struct card_info *card;
+        struct mode_info *mi;
+        int i;
+
+        for (card = video_cards; card < video_cards_end; card++) {
+                mi = card->modes;
+                for (i = 0; i < card->nmodes; i++, mi++) {
+                        if (mi->mode == mode)
+                                return 1;
+                }
+        }
+
+        return 0;
+}
+
+/* Set mode (without recalc) */
+static int raw_set_mode(u16 mode, u16 *real_mode)
+{
+        int nmode, i;
+        struct card_info *card;
+        struct mode_info *mi;
+
+        /* Drop the recalc bit if set */
+        mode &= ~VIDEO_RECALC;
+
+        /* Scan for mode based on fixed ID, position, or resolution */
+        nmode = 0;
+        for (card = video_cards; card < video_cards_end; card++) {
+                mi = card->modes;
+                for (i = 0; i < card->nmodes; i++, mi++) {
+                        int visible = mi->x || mi->y;
+
+                        if ((mode == nmode && visible) ||
+                            mode == mi->mode ||
+                            mode == (mi->y << 8)+mi->x) {
+                                *real_mode = mi->mode;
+                                return card->set_mode(mi);
+                        }
+
+                        if (visible)
+                                nmode++;
+                }
+        }
+
+        /* Nothing found?  Is it an "exceptional" (unprobed) mode? */
+        for (card = video_cards; card < video_cards_end; card++) {
+                if (mode >= card->xmode_first &&
+                    mode < card->xmode_first+card->xmode_n) {
+                        struct mode_info mix;
+                        *real_mode = mix.mode = mode;
+                        mix.x = mix.y = 0;
+                        return card->set_mode(&mix);
+                }
+        }
+
+        /* Otherwise, failure... */
+        return -1;
+}
+
+/*
+ * Recalculate the vertical video cutoff (hack!)
+ */
+static void vga_recalc_vertical(void)
+{
+        unsigned int font_size, rows;
+        u16 crtc;
+        u8 pt, ov;
+
+        set_fs(0);
+        font_size = rdfs8(0x485); /* BIOS: font size (pixels) */
+        rows = force_y ? force_y : rdfs8(0x484)+1; /* Text rows */
+
+        rows *= font_size;      /* Visible scan lines */
+        rows--;                 /* ... minus one */
+
+        crtc = vga_crtc();
+
+        pt = in_idx(crtc, 0x11);
+        pt &= ~0x80;            /* Unlock CR0-7 */
+        out_idx(pt, crtc, 0x11);
+
+        out_idx((u8)rows, crtc, 0x12); /* Lower height register */
+
+        ov = in_idx(crtc, 0x07); /* Overflow register */
+        ov &= 0xbd;
+        ov |= (rows >> (8-1)) & 0x02;
+        ov |= (rows >> (9-6)) & 0x40;
+        out_idx(ov, crtc, 0x07);
+}
+
+/* Set mode (with recalc if specified) */
+int set_mode(u16 mode)
+{
+        int rv;
+        u16 real_mode;
+
+        /* Very special mode numbers... */
+        if (mode == VIDEO_CURRENT_MODE)
+                return 0;       /* Nothing to do... */
+        else if (mode == NORMAL_VGA)
+                mode = VIDEO_80x25;
+        else if (mode == EXTENDED_VGA)
+                mode = VIDEO_8POINT;
+
+        rv = raw_set_mode(mode, &real_mode);
+        if (rv)
+                return rv;
+
+        if (mode & VIDEO_RECALC)
+                vga_recalc_vertical();
+
+        /* Save the canonical mode number for the kernel, not
+           an alias, size specification or menu position */
+#ifndef _WAKEUP
+        boot_params.hdr.vid_mode = real_mode;
+#endif
+        return 0;
+}