147 lines
4.7 KiB
C++
147 lines
4.7 KiB
C++
/*
|
|
* Copyright (c) 2011, 2012, 2015 Jonas 'Sortie' Termansen.
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*
|
|
* vga.cpp
|
|
* A Video Graphics Array driver.
|
|
*/
|
|
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
|
|
#include <sortix/kernel/descriptor.h>
|
|
#include <sortix/kernel/inode.h>
|
|
#include <sortix/kernel/interlock.h>
|
|
#include <sortix/kernel/ioctx.h>
|
|
#include <sortix/kernel/ioport.h>
|
|
#include <sortix/kernel/kernel.h>
|
|
#include <sortix/kernel/kthread.h>
|
|
#include <sortix/kernel/process.h>
|
|
#include <sortix/kernel/refcount.h>
|
|
#include <sortix/kernel/scheduler.h>
|
|
#include <sortix/kernel/syscall.h>
|
|
|
|
#include "fs/util.h"
|
|
#include "vga.h"
|
|
#include "vgafont.h"
|
|
|
|
namespace Sortix {
|
|
namespace VGA {
|
|
|
|
uint8_t* const VGA = (uint8_t*) 0xB8000;
|
|
const unsigned WIDTH = 80;
|
|
const unsigned HEIGHT = 25;
|
|
const size_t VGA_SIZE = sizeof(uint16_t) * WIDTH * HEIGHT;
|
|
|
|
static void WriteIndex(uint16_t port, uint8_t index, uint8_t value)
|
|
{
|
|
outport8(port, index);
|
|
outport8(port+1, value);
|
|
}
|
|
|
|
static uint8_t ReadIndex(uint16_t port, uint8_t index)
|
|
{
|
|
outport8(port, index);
|
|
return inport8(port+1);
|
|
}
|
|
|
|
static uint8_t ReplaceIndex(uint16_t port, uint8_t index, uint8_t value)
|
|
{
|
|
uint8_t ret = ReadIndex(port, index);
|
|
WriteIndex(port, index, value);
|
|
return ret;
|
|
}
|
|
|
|
static void FetchVGAFont(uint8_t* font)
|
|
{
|
|
// TODO: I just got these magic constants off the net.
|
|
// Select plane 2 for reading.
|
|
uint8_t old_03ce_04 = ReplaceIndex(0x03CE, 0x04, 0x02);
|
|
// Clear even/odd mode.
|
|
uint8_t old_03ce_05 = ReplaceIndex(0x03CE, 0x05, 0x04);
|
|
// Map VGA Memory to 0xA0000 (Select 0xA0000-0xAFFFF).
|
|
uint8_t old_03ce_06 = ReplaceIndex(0x03CE, 0x06, 0x04);
|
|
// Set bitplane 2.
|
|
uint8_t old_03c4_02 = ReplaceIndex(0x03C4, 0x02, 0x04);
|
|
// Clear even/odd mode (the other way, don't ask why).
|
|
uint8_t old_03c4_04 = ReplaceIndex(0x03C4, 0x04, 0x07);
|
|
// The font data is now at 0xA0000, so fetch it. Note that there is
|
|
// reserved room for a 8x32 resolution but we are using 8x16.
|
|
const uint8_t* data = (const uint8_t*) 0xA0000UL;
|
|
// Patch the replacement chararacter onto character 0.
|
|
memcpy((uint8_t*) data + ((32*8)/8 * 0), font_replacement_character, VGA_FONT_CHARSIZE);
|
|
for ( size_t i = 0; i < VGA_FONT_NUMCHARS; i++ )
|
|
{
|
|
const uint8_t* src = data + (32*8)/8 * i;
|
|
uint8_t* dest = font + VGA_FONT_CHARSIZE * i;
|
|
memcpy(dest, src, VGA_FONT_CHARSIZE);
|
|
}
|
|
// Restore the VGA state.
|
|
WriteIndex(0x03C4, 0x02, old_03c4_02);
|
|
WriteIndex(0x03C4, 0x04, old_03c4_04);
|
|
WriteIndex(0x03CE, 0x05, old_03ce_05);
|
|
WriteIndex(0x03CE, 0x06, old_03ce_06);
|
|
WriteIndex(0x03CE, 0x04, old_03ce_04);
|
|
}
|
|
|
|
const uint8_t* GetFont()
|
|
{
|
|
return vgafont;
|
|
}
|
|
|
|
void Init(const char* devpath, Ref<Descriptor> slashdev)
|
|
{
|
|
if ( !Log::fallback_framebuffer )
|
|
FetchVGAFont(vgafont);
|
|
|
|
ioctx_t ctx; SetupKernelIOCtx(&ctx);
|
|
|
|
// Setup the vgafont device.
|
|
Ref<Inode> vgafontnode(new UtilMemoryBuffer(slashdev->dev, (ino_t) 0, 0, 0,
|
|
0660, vgafont, sizeof(vgafont),
|
|
false, false));
|
|
if ( !vgafontnode )
|
|
PanicF("Unable to allocate %s/vgafont inode.", devpath);
|
|
if ( LinkInodeInDir(&ctx, slashdev, "vgafont", vgafontnode) != 0 )
|
|
PanicF("Unable to link %s/vgafont to vga font.", devpath);
|
|
|
|
if ( Log::fallback_framebuffer )
|
|
return;
|
|
|
|
// Setup the vga device.
|
|
Ref<Inode> vganode(new UtilMemoryBuffer(slashdev->dev, (ino_t) 0, 0, 0,
|
|
0660, VGA, VGA_SIZE, true, false));
|
|
if ( !vganode )
|
|
PanicF("Unable to allocate %s/vga inode.", devpath);
|
|
if ( LinkInodeInDir(&ctx, slashdev, "vga", vganode) != 0 )
|
|
PanicF("Unable to link %s/vga to vga.", devpath);
|
|
}
|
|
|
|
// Changes the position of the hardware cursor.
|
|
void SetCursor(unsigned x, unsigned y)
|
|
{
|
|
unsigned value = x + y * WIDTH;
|
|
|
|
// This sends a command to indicies 14 and 15 in the
|
|
// CRT Control Register of the VGA controller. These
|
|
// are the high and low bytes of the index that show
|
|
// where the hardware cursor is to be 'blinking'.
|
|
outport8(0x3D4, 14);
|
|
outport8(0x3D5, (value >> 8) & 0xFF);
|
|
outport8(0x3D4, 15);
|
|
outport8(0x3D5, (value >> 0) & 0xFF);
|
|
}
|
|
|
|
} // namespace VGA
|
|
} // namespace Sortix
|