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-rw-r--r--arch/i386/boot/video-vesa.c284
1 files changed, 284 insertions, 0 deletions
diff --git a/arch/i386/boot/video-vesa.c b/arch/i386/boot/video-vesa.c
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index 00000000000..e6aa9eb8d93
--- /dev/null
+++ b/arch/i386/boot/video-vesa.c
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+/* -*- 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-vesa.c
+ *
+ * VESA text modes
+ */
+
+#include "boot.h"
+#include "video.h"
+#include "vesa.h"
+
+/* VESA information */
+static struct vesa_general_info vginfo;
+static struct vesa_mode_info vminfo;
+
+__videocard video_vesa;
+
+static void vesa_store_mode_params_graphics(void);
+
+static int vesa_probe(void)
+{
+#if defined(CONFIG_VIDEO_VESA) || defined(CONFIG_FIRMWARE_EDID)
+ u16 ax;
+ u16 mode;
+ addr_t mode_ptr;
+ struct mode_info *mi;
+ int nmodes = 0;
+
+ video_vesa.modes = GET_HEAP(struct mode_info, 0);
+
+ vginfo.signature = VBE2_MAGIC;
+
+ /* Optimistically assume a VESA BIOS is register-clean... */
+ ax = 0x4f00;
+ asm("int $0x10" : "+a" (ax), "=m" (vginfo) : "D" (&vginfo));
+
+ if (ax != 0x004f ||
+ vginfo.signature != VESA_MAGIC ||
+ vginfo.version < 0x0102)
+ return 0; /* Not present */
+#endif /* CONFIG_VIDEO_VESA || CONFIG_FIRMWARE_EDID */
+#ifdef CONFIG_VIDEO_VESA
+ set_fs(vginfo.video_mode_ptr.seg);
+ mode_ptr = vginfo.video_mode_ptr.off;
+
+ while ((mode = rdfs16(mode_ptr)) != 0xffff) {
+ mode_ptr += 2;
+
+ if (heap_free() < sizeof(struct mode_info))
+ break; /* Heap full, can't save mode info */
+
+ if (mode & ~0x1ff)
+ continue;
+
+ memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
+
+ ax = 0x4f01;
+ asm("int $0x10"
+ : "+a" (ax), "=m" (vminfo)
+ : "c" (mode), "D" (&vminfo));
+
+ if (ax != 0x004f)
+ continue;
+
+ if ((vminfo.mode_attr & 0x15) == 0x05) {
+ /* Text Mode, TTY BIOS supported,
+ supported by hardware */
+ mi = GET_HEAP(struct mode_info, 1);
+ mi->mode = mode + VIDEO_FIRST_VESA;
+ mi->x = vminfo.h_res;
+ mi->y = vminfo.v_res;
+ nmodes++;
+ } else if ((vminfo.mode_attr & 0x99) == 0x99) {
+#ifdef CONFIG_FB
+ /* Graphics mode, color, linear frame buffer
+ supported -- register the mode but hide from
+ the menu. Only do this if framebuffer is
+ configured, however, otherwise the user will
+ be left without a screen. */
+ mi = GET_HEAP(struct mode_info, 1);
+ mi->mode = mode + VIDEO_FIRST_VESA;
+ mi->x = mi->y = 0;
+ nmodes++;
+#endif
+ }
+ }
+
+ return nmodes;
+#else
+ return 0;
+#endif /* CONFIG_VIDEO_VESA */
+}
+
+static int vesa_set_mode(struct mode_info *mode)
+{
+ u16 ax;
+ int is_graphic;
+ u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
+
+ memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
+
+ ax = 0x4f01;
+ asm("int $0x10"
+ : "+a" (ax), "=m" (vminfo)
+ : "c" (vesa_mode), "D" (&vminfo));
+
+ if (ax != 0x004f)
+ return -1;
+
+ if ((vminfo.mode_attr & 0x15) == 0x05) {
+ /* It's a supported text mode */
+ is_graphic = 0;
+ } else if ((vminfo.mode_attr & 0x99) == 0x99) {
+ /* It's a graphics mode with linear frame buffer */
+ is_graphic = 1;
+ vesa_mode |= 0x4000; /* Request linear frame buffer */
+ } else {
+ return -1; /* Invalid mode */
+ }
+
+
+ ax = 0x4f02;
+ asm volatile("int $0x10"
+ : "+a" (ax)
+ : "b" (vesa_mode), "D" (0));
+
+ if (ax != 0x004f)
+ return -1;
+
+ graphic_mode = is_graphic;
+ if (!is_graphic) {
+ /* Text mode */
+ force_x = mode->x;
+ force_y = mode->y;
+ do_restore = 1;
+ } else {
+ /* Graphics mode */
+ vesa_store_mode_params_graphics();
+ }
+
+ return 0;
+}
+
+
+/* Switch DAC to 8-bit mode */
+static void vesa_dac_set_8bits(void)
+{
+ u8 dac_size = 6;
+
+ /* If possible, switch the DAC to 8-bit mode */
+ if (vginfo.capabilities & 1) {
+ u16 ax, bx;
+
+ ax = 0x4f08;
+ bx = 0x0800;
+ asm volatile(INT10
+ : "+a" (ax), "+b" (bx)
+ : : "ecx", "edx", "esi", "edi");
+
+ if (ax == 0x004f)
+ dac_size = bx >> 8;
+ }
+
+ /* Set the color sizes to the DAC size, and offsets to 0 */
+ boot_params.screen_info.red_size = dac_size;
+ boot_params.screen_info.green_size = dac_size;
+ boot_params.screen_info.blue_size = dac_size;
+ boot_params.screen_info.rsvd_size = dac_size;
+
+ boot_params.screen_info.red_pos = 0;
+ boot_params.screen_info.green_pos = 0;
+ boot_params.screen_info.blue_pos = 0;
+ boot_params.screen_info.rsvd_pos = 0;
+}
+
+/* Save the VESA protected mode info */
+static void vesa_store_pm_info(void)
+{
+ u16 ax, bx, di, es;
+
+ ax = 0x4f0a;
+ bx = di = 0;
+ asm("pushw %%es; "INT10"; movw %%es,%0; popw %%es"
+ : "=d" (es), "+a" (ax), "+b" (bx), "+D" (di)
+ : : "ecx", "esi");
+
+ if (ax != 0x004f)
+ return;
+
+ boot_params.screen_info.vesapm_seg = es;
+ boot_params.screen_info.vesapm_off = di;
+}
+
+/*
+ * Save video mode parameters for graphics mode
+ */
+static void vesa_store_mode_params_graphics(void)
+{
+ /* Tell the kernel we're in VESA graphics mode */
+ boot_params.screen_info.orig_video_isVGA = 0x23;
+
+ /* Mode parameters */
+ boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
+ boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
+ boot_params.screen_info.lfb_width = vminfo.h_res;
+ boot_params.screen_info.lfb_height = vminfo.v_res;
+ boot_params.screen_info.lfb_depth = vminfo.bpp;
+ boot_params.screen_info.pages = vminfo.image_planes;
+ boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
+ memcpy(&boot_params.screen_info.red_size,
+ &vminfo.rmask, 8);
+
+ /* General parameters */
+ boot_params.screen_info.lfb_size = vginfo.total_memory;
+
+ if (vminfo.bpp <= 8)
+ vesa_dac_set_8bits();
+
+ vesa_store_pm_info();
+}
+
+/*
+ * Save EDID information for the kernel; this is invoked, separately,
+ * after mode-setting.
+ */
+void vesa_store_edid(void)
+{
+#ifdef CONFIG_FIRMWARE_EDID
+ u16 ax, bx, cx, dx, di;
+
+ /* Apparently used as a nonsense token... */
+ memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
+
+ if (vginfo.version < 0x0200)
+ return; /* EDID requires VBE 2.0+ */
+
+ ax = 0x4f15; /* VBE DDC */
+ bx = 0x0000; /* Report DDC capabilities */
+ cx = 0; /* Controller 0 */
+ di = 0; /* ES:DI must be 0 by spec */
+
+ /* Note: The VBE DDC spec is different from the main VESA spec;
+ we genuinely have to assume all registers are destroyed here. */
+
+ asm("pushw %%es; movw %2,%%es; "INT10"; popw %%es"
+ : "+a" (ax), "+b" (bx)
+ : "c" (cx), "D" (di)
+ : "esi");
+
+ if (ax != 0x004f)
+ return; /* No EDID */
+
+ /* BH = time in seconds to transfer EDD information */
+ /* BL = DDC level supported */
+
+ ax = 0x4f15; /* VBE DDC */
+ bx = 0x0001; /* Read EDID */
+ cx = 0; /* Controller 0 */
+ dx = 0; /* EDID block number */
+ di =(size_t) &boot_params.edid_info; /* (ES:)Pointer to block */
+ asm(INT10
+ : "+a" (ax), "+b" (bx), "+d" (dx)
+ : "c" (cx), "D" (di)
+ : "esi");
+#endif /* CONFIG_FIRMWARE_EDID */
+}
+
+__videocard video_vesa =
+{
+ .card_name = "VESA",
+ .probe = vesa_probe,
+ .set_mode = vesa_set_mode,
+ .xmode_first = VIDEO_FIRST_VESA,
+ .xmode_n = 0x200,
+};