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Diffstat (limited to 'arch/i386/boot/video-vesa.c')
| -rw-r--r-- | arch/i386/boot/video-vesa.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/arch/i386/boot/video-vesa.c b/arch/i386/boot/video-vesa.c new file mode 100644 index 000000000000..e6aa9eb8d93a --- /dev/null +++ b/arch/i386/boot/video-vesa.c @@ -0,0 +1,284 @@ +/* -*- 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, +}; |