linux-zen-server/arch/x86/boot/video-vesa.c

280 lines
6.6 KiB
C
Raw Permalink Normal View History

2023-08-30 17:53:23 +02:00
// SPDX-License-Identifier: GPL-2.0-only
/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
* Copyright 2009 Intel Corporation; author H. Peter Anvin
*
* ----------------------------------------------------------------------- */
/*
* VESA text modes
*/
#include "boot.h"
#include "video.h"
#include "vesa.h"
#include "string.h"
/* VESA information */
static struct vesa_general_info vginfo;
static struct vesa_mode_info vminfo;
static __videocard video_vesa;
#ifndef _WAKEUP
static void vesa_store_mode_params_graphics(void);
#else /* _WAKEUP */
static inline void vesa_store_mode_params_graphics(void) {}
#endif /* _WAKEUP */
static int vesa_probe(void)
{
struct biosregs ireg, oreg;
u16 mode;
addr_t mode_ptr;
struct mode_info *mi;
int nmodes = 0;
video_vesa.modes = GET_HEAP(struct mode_info, 0);
initregs(&ireg);
ireg.ax = 0x4f00;
ireg.di = (size_t)&vginfo;
intcall(0x10, &ireg, &oreg);
if (oreg.ax != 0x004f ||
vginfo.signature != VESA_MAGIC ||
vginfo.version < 0x0102)
return 0; /* Not present */
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... */
ireg.ax = 0x4f01;
ireg.cx = mode;
ireg.di = (size_t)&vminfo;
intcall(0x10, &ireg, &oreg);
if (oreg.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->depth = 0; /* text */
mi->x = vminfo.h_res;
mi->y = vminfo.v_res;
nmodes++;
} else if ((vminfo.mode_attr & 0x99) == 0x99 &&
(vminfo.memory_layout == 4 ||
vminfo.memory_layout == 6) &&
vminfo.memory_planes == 1) {
#ifdef CONFIG_BOOT_VESA_SUPPORT
/* Graphics mode, color, linear frame buffer
supported. Only register the mode if
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->depth = vminfo.bpp;
mi->x = vminfo.h_res;
mi->y = vminfo.v_res;
nmodes++;
#endif
}
}
return nmodes;
}
static int vesa_set_mode(struct mode_info *mode)
{
struct biosregs ireg, oreg;
int is_graphic;
u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
memset(&vminfo, 0, sizeof(vminfo)); /* Just in case... */
initregs(&ireg);
ireg.ax = 0x4f01;
ireg.cx = vesa_mode;
ireg.di = (size_t)&vminfo;
intcall(0x10, &ireg, &oreg);
if (oreg.ax != 0x004f)
return -1;
if ((vminfo.mode_attr & 0x15) == 0x05) {
/* It's a supported text mode */
is_graphic = 0;
#ifdef CONFIG_BOOT_VESA_SUPPORT
} 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 */
#endif
} else {
return -1; /* Invalid mode */
}
initregs(&ireg);
ireg.ax = 0x4f02;
ireg.bx = vesa_mode;
intcall(0x10, &ireg, &oreg);
if (oreg.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;
}
#ifndef _WAKEUP
/* Switch DAC to 8-bit mode */
static void vesa_dac_set_8bits(void)
{
struct biosregs ireg, oreg;
u8 dac_size = 6;
/* If possible, switch the DAC to 8-bit mode */
if (vginfo.capabilities & 1) {
initregs(&ireg);
ireg.ax = 0x4f08;
ireg.bh = 0x08;
intcall(0x10, &ireg, &oreg);
if (oreg.ax == 0x004f)
dac_size = oreg.bh;
}
/* 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)
{
struct biosregs ireg, oreg;
initregs(&ireg);
ireg.ax = 0x4f0a;
intcall(0x10, &ireg, &oreg);
if (oreg.ax != 0x004f)
return;
boot_params.screen_info.vesapm_seg = oreg.es;
boot_params.screen_info.vesapm_off = oreg.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 = VIDEO_TYPE_VLFB;
/* 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
struct biosregs ireg, oreg;
/* 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+ */
initregs(&ireg);
ireg.ax = 0x4f15; /* VBE DDC */
/* ireg.bx = 0x0000; */ /* Report DDC capabilities */
/* ireg.cx = 0; */ /* Controller 0 */
ireg.es = 0; /* ES:DI must be 0 by spec */
intcall(0x10, &ireg, &oreg);
if (oreg.ax != 0x004f)
return; /* No EDID */
/* BH = time in seconds to transfer EDD information */
/* BL = DDC level supported */
ireg.ax = 0x4f15; /* VBE DDC */
ireg.bx = 0x0001; /* Read EDID */
/* ireg.cx = 0; */ /* Controller 0 */
/* ireg.dx = 0; */ /* EDID block number */
ireg.es = ds();
ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
intcall(0x10, &ireg, &oreg);
#endif /* CONFIG_FIRMWARE_EDID */
}
#endif /* not _WAKEUP */
static __videocard video_vesa =
{
.card_name = "VESA",
.probe = vesa_probe,
.set_mode = vesa_set_mode,
.xmode_first = VIDEO_FIRST_VESA,
.xmode_n = 0x200,
};