Minix2.0/src/kernel/console.c
/* Code and data for the IBM console driver.
*
* The 6845 video controller used by the IBM PC shares its video memory with
* the CPU somewhere in the 0xB0000 memory bank. To the 6845 this memory
* consists of 16-bit words. Each word has a character code in the low byte
* and a so-called attribute byte in the high byte. The CPU directly modifies
* video memory to display characters, and sets two registers on the 6845 that
* specify the video origin and the cursor position. The video origin is the
* place in video memory where the first character (upper left corner) can
* be found. Moving the origin is a fast way to scroll the screen. Some
* video adapters wrap around the top of video memory, so the origin can
* move without bounds. For other adapters screen memory must sometimes be
* moved to reset the origin. All computations on video memory use character
* (word) addresses for simplicity and assume there is no wrapping. The
* assembly support functions translate the word addresses to byte addresses
* and the scrolling function worries about wrapping.
*/
#include "kernel.h"
#include <termios.h>
#include <minix/callnr.h>
#include <minix/com.h>
#include "protect.h"
#include "tty.h"
#include "proc.h"
/* Definitions used by the console driver. */
#define MONO_BASE 0xB0000L /* base of mono video memory */
#define COLOR_BASE 0xB8000L /* base of color video memory */
#define MONO_SIZE 0x1000 /* 4K mono video memory */
#define COLOR_SIZE 0x4000 /* 16K color video memory */
#define EGA_SIZE 0x8000 /* EGA & VGA have at least 32K */
#define BLANK_COLOR 0x0700 /* determines cursor color on blank screen */
#define SCROLL_UP 0 /* scroll forward */
#define SCROLL_DOWN 1 /* scroll backward */
#define BLANK_MEM ((u16_t *) 0) /* tells mem_vid_copy() to blank the screen */
#define CONS_RAM_WORDS 80 /* video ram buffer size */
#define MAX_ESC_PARMS 2 /* number of escape sequence params allowed */
/* Constants relating to the controller chips. */
#define M_6845 0x3B4 /* port for 6845 mono */
#define C_6845 0x3D4 /* port for 6845 color */
#define EGA 0x3C4 /* port for EGA card */
#define INDEX 0 /* 6845's index register */
#define DATA 1 /* 6845's data register */
#define VID_ORG 12 /* 6845's origin register */
#define CURSOR 14 /* 6845's cursor register */
/* Beeper. */
#define BEEP_FREQ 0x0533 /* value to put into timer to set beep freq */
#define B_TIME 3 /* length of CTRL-G beep is ticks */
/* definitions used for font management */
#define GA_SEQUENCER_INDEX 0x3C4
#define GA_SEQUENCER_DATA 0x3C5
#define GA_GRAPHICS_INDEX 0x3CE
#define GA_GRAPHICS_DATA 0x3CF
#define GA_VIDEO_ADDRESS 0xA0000L
#define GA_FONT_SIZE 8192
/* Global variables used by the console driver. */
PUBLIC unsigned vid_seg; /* video ram selector (0xB0000 or 0xB8000) */
PUBLIC unsigned vid_size; /* 0x2000 for color or 0x0800 for mono */
PUBLIC unsigned vid_mask; /* 0x1FFF for color or 0x07FF for mono */
PUBLIC unsigned blank_color = BLANK_COLOR; /* display code for blank */
/* Private variables used by the console driver. */
PRIVATE int vid_port; /* I/O port for accessing 6845 */
PRIVATE int wrap; /* hardware can wrap? */
PRIVATE int softscroll; /* 1 = software scrolling, 0 = hardware */
PRIVATE unsigned vid_base; /* base of video ram (0xB000 or 0xB800) */
PRIVATE int beeping; /* speaker is beeping? */
#define scr_width 80 /* # characters on a line */
#define scr_lines 25 /* # lines on the screen */
#define scr_size (80*25) /* # characters on the screen */
/* Per console data. */
typedef struct console {
tty_t *c_tty; /* associated TTY struct */
int c_column; /* current column number (0-origin) */
int c_row; /* current row (0 at top of screen) */
int c_rwords; /* number of WORDS (not bytes) in outqueue */
unsigned c_start; /* start of video memory of this console */
unsigned c_limit; /* limit of this console's video memory */
unsigned c_org; /* location in RAM where 6845 base points */
unsigned c_cur; /* current position of cursor in video RAM */
unsigned c_attr; /* character attribute */
unsigned c_blank; /* blank attribute */
char c_esc_state; /* 0=normal, 1=ESC, 2=ESC[ */
char c_esc_intro; /* Distinguishing character following ESC */
int *c_esc_parmp; /* pointer to current escape parameter */
int c_esc_parmv[MAX_ESC_PARMS]; /* list of escape parameters */
u16_t c_ramqueue[CONS_RAM_WORDS]; /* buffer for video RAM */
} console_t;
PRIVATE int nr_cons= 1; /* actual number of consoles */
PRIVATE console_t cons_table[NR_CONS];
PRIVATE console_t *curcons; /* currently visible */
/* Color if using a color controller. */
#define color (vid_port == C_6845)
/* Map from ANSI colors to the attributes used by the PC */
PRIVATE int ansi_colors[8] = {0, 4, 2, 6, 1, 5, 3, 7};
/* Structure used for font management */
struct sequence {
unsigned short index;
unsigned char port;
unsigned char value;
};
FORWARD _PROTOTYPE( void cons_write, (struct tty *tp) );
FORWARD _PROTOTYPE( void cons_echo, (tty_t *tp, int c) );
FORWARD _PROTOTYPE( void out_char, (console_t *cons, int c) );
FORWARD _PROTOTYPE( void beep, (void) );
FORWARD _PROTOTYPE( void do_escape, (console_t *cons, int c) );
FORWARD _PROTOTYPE( void flush, (console_t *cons) );
FORWARD _PROTOTYPE( void parse_escape, (console_t *cons, int c) );
FORWARD _PROTOTYPE( void scroll_screen, (console_t *cons, int dir) );
FORWARD _PROTOTYPE( void set_6845, (int reg, unsigned val) );
FORWARD _PROTOTYPE( void stop_beep, (void) );
FORWARD _PROTOTYPE( void cons_org0, (void) );
FORWARD _PROTOTYPE( void ga_program, (struct sequence *seq) );
/*===========================================================================*
* cons_write *
*===========================================================================*/
PRIVATE void cons_write(tp)
register struct tty *tp; /* tells which terminal is to be used */
{
/* Copy as much data as possible to the output queue, then start I/O. On
* memory-mapped terminals, such as the IBM console, the I/O will also be
* finished, and the counts updated. Keep repeating until all I/O done.
*/
int count;
register char *tbuf;
char buf[64];
phys_bytes user_phys;
console_t *cons = tp->tty_priv;
/* Check quickly for nothing to do, so this can be called often without
* unmodular tests elsewhere.
*/
if ((count = tp->tty_outleft) == 0 || tp->tty_inhibited) return;
/* Copy the user bytes to buf[] for decent addressing. Loop over the
* copies, since the user buffer may be much larger than buf[].
*/
do {
if (count > sizeof(buf)) count = sizeof(buf);
user_phys = proc_vir2phys(proc_addr(tp->tty_outproc), tp->tty_out_vir);
phys_copy(user_phys, vir2phys(buf), (phys_bytes) count);
tbuf = buf;
/* Update terminal data structure. */
tp->tty_out_vir += count;
tp->tty_outcum += count;
tp->tty_outleft -= count;
/* Output each byte of the copy to the screen. Avoid calling
* out_char() for the "easy" characters, put them into the buffer
* directly.
*/
do {
if ((unsigned) *tbuf < ' ' || cons->c_esc_state > 0
|| cons->c_column >= scr_width
|| cons->c_rwords >= buflen(cons->c_ramqueue))
{
out_char(cons, *tbuf++);
} else {
cons->c_ramqueue[cons->c_rwords++] =
cons->c_attr | (*tbuf++ & BYTE);
cons->c_column++;
}
} while (--count != 0);
} while ((count = tp->tty_outleft) != 0 && !tp->tty_inhibited);
flush(cons); /* transfer anything buffered to the screen */
/* Reply to the writer if all output is finished. */
if (tp->tty_outleft == 0) {
tty_reply(tp->tty_outrepcode, tp->tty_outcaller, tp->tty_outproc,
tp->tty_outcum);
tp->tty_outcum = 0;
}
}
/*===========================================================================*
* cons_echo *
*===========================================================================*/
PRIVATE void cons_echo(tp, c)
register tty_t *tp; /* pointer to tty struct */
int c; /* character to be echoed */
{
/* Echo keyboard input (print & flush). */
console_t *cons = tp->tty_priv;
out_char(cons, c);
flush(cons);
}
/*===========================================================================*
* out_char *
*===========================================================================*/
PRIVATE void out_char(cons, c)
register console_t *cons; /* pointer to console struct */
int c; /* character to be output */
{
/* Output a character on the console. Check for escape sequences first. */
if (cons->c_esc_state > 0) {
parse_escape(cons, c);
return;
}
switch(c) {
case 000: /* null is typically used for padding */
return; /* better not do anything */
case 007: /* ring the bell */
flush(cons); /* print any chars queued for output */
beep();
return;
case '\b': /* backspace */
if (--cons->c_column < 0) {
if (--cons->c_row >= 0) cons->c_column += scr_width;
}
flush(cons);
return;
case '\n': /* line feed */
if ((cons->c_tty->tty_termios.c_oflag & (OPOST|ONLCR))
== (OPOST|ONLCR)) {
cons->c_column = 0;
}
/*FALL THROUGH*/
case 013: /* CTRL-K */
case 014: /* CTRL-L */
if (cons->c_row == scr_lines-1) {
scroll_screen(cons, SCROLL_UP);
} else {
cons->c_row++;
}
flush(cons);
return;
case '\r': /* carriage return */
cons->c_column = 0;
flush(cons);
return;
case '\t': /* tab */
cons->c_column = (cons->c_column + TAB_SIZE) & ~TAB_MASK;
if (cons->c_column > scr_width) {
cons->c_column -= scr_width;
if (cons->c_row == scr_lines-1) {
scroll_screen(cons, SCROLL_UP);
} else {
cons->c_row++;
}
}
flush(cons);
return;
case 033: /* ESC - start of an escape sequence */
flush(cons); /* print any chars queued for output */
cons->c_esc_state = 1; /* mark ESC as seen */
return;
default: /* printable chars are stored in ramqueue */
if (cons->c_column >= scr_width) {
if (!LINEWRAP) return;
if (cons->c_row == scr_lines-1) {
scroll_screen(cons, SCROLL_UP);
} else {
cons->c_row++;
}
cons->c_column = 0;
flush(cons);
}
if (cons->c_rwords == buflen(cons->c_ramqueue)) flush(cons);
cons->c_ramqueue[cons->c_rwords++] = cons->c_attr | (c & BYTE);
cons->c_column++; /* next column */
return;
}
}
/*===========================================================================*
* scroll_screen *
*===========================================================================*/
PRIVATE void scroll_screen(cons, dir)
register console_t *cons; /* pointer to console struct */
int dir; /* SCROLL_UP or SCROLL_DOWN */
{
unsigned new_line, new_org, chars;
flush(cons);
chars = scr_size - scr_width; /* one screen minus one line */
/* Scrolling the screen is a real nuisance due to the various incompatible
* video cards. This driver supports software scrolling (Hercules?),
* hardware scrolling (mono and CGA cards) and hardware scrolling without
* wrapping (EGA cards). In the latter case we must make sure that
* c_start <= c_org && c_org + scr_size <= c_limit
* holds, because EGA doesn't wrap around the end of video memory.
*/
if (dir == SCROLL_UP) {
/* Scroll one line up in 3 ways: soft, avoid wrap, use origin. */
if (softscroll) {
vid_vid_copy(cons->c_start + scr_width, cons->c_start, chars);
} else
if (!wrap && cons->c_org + scr_size + scr_width >= cons->c_limit) {
vid_vid_copy(cons->c_org + scr_width, cons->c_start, chars);
cons->c_org = cons->c_start;
} else {
cons->c_org = (cons->c_org + scr_width) & vid_mask;
}
new_line = (cons->c_org + chars) & vid_mask;
} else {
/* Scroll one line down in 3 ways: soft, avoid wrap, use origin. */
if (softscroll) {
vid_vid_copy(cons->c_start, cons->c_start + scr_width, chars);
} else
if (!wrap && cons->c_org < cons->c_start + scr_width) {
new_org = cons->c_limit - scr_size;
vid_vid_copy(cons->c_org, new_org + scr_width, chars);
cons->c_org = new_org;
} else {
cons->c_org = (cons->c_org - scr_width) & vid_mask;
}
new_line = cons->c_org;
}
/* Blank the new line at top or bottom. */
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, new_line, scr_width);
/* Set the new video origin. */
if (cons == curcons) set_6845(VID_ORG, cons->c_org);
flush(cons);
}
/*===========================================================================*
* flush *
*===========================================================================*/
PRIVATE void flush(cons)
register console_t *cons; /* pointer to console struct */
{
/* Send characters buffered in 'ramqueue' to screen memory, check the new
* cursor position, compute the new hardware cursor position and set it.
*/
unsigned cur;
tty_t *tp = cons->c_tty;
/* Have the characters in 'ramqueue' transferred to the screen. */
if (cons->c_rwords > 0) {
mem_vid_copy(cons->c_ramqueue, cons->c_cur, cons->c_rwords);
cons->c_rwords = 0;
/* TTY likes to know the current column and if echoing messed up. */
tp->tty_position = cons->c_column;
tp->tty_reprint = TRUE;
}
/* Check and update the cursor position. */
if (cons->c_column < 0) cons->c_column = 0;
if (cons->c_column > scr_width) cons->c_column = scr_width;
if (cons->c_row < 0) cons->c_row = 0;
if (cons->c_row >= scr_lines) cons->c_row = scr_lines - 1;
cur = cons->c_org + cons->c_row * scr_width + cons->c_column;
if (cur != cons->c_cur) {
if (cons == curcons) set_6845(CURSOR, cur);
cons->c_cur = cur;
}
}
/*===========================================================================*
* parse_escape *
*===========================================================================*/
PRIVATE void parse_escape(cons, c)
register console_t *cons; /* pointer to console struct */
char c; /* next character in escape sequence */
{
/* The following ANSI escape sequences are currently supported.
* If n and/or m are omitted, they default to 1.
* ESC [nA moves up n lines
* ESC [nB moves down n lines
* ESC [nC moves right n spaces
* ESC [nD moves left n spaces
* ESC [m;nH" moves cursor to (m,n)
* ESC [J clears screen from cursor
* ESC [K clears line from cursor
* ESC [nL inserts n lines ar cursor
* ESC [nM deletes n lines at cursor
* ESC [nP deletes n chars at cursor
* ESC [n@ inserts n chars at cursor
* ESC [nm enables rendition n (0=normal, 4=bold, 5=blinking, 7=reverse)
* ESC M scrolls the screen backwards if the cursor is on the top line
*/
switch (cons->c_esc_state) {
case 1: /* ESC seen */
cons->c_esc_intro = '\0';
cons->c_esc_parmp = cons->c_esc_parmv;
cons->c_esc_parmv[0] = cons->c_esc_parmv[1] = 0;
switch (c) {
case '[': /* Control Sequence Introducer */
cons->c_esc_intro = c;
cons->c_esc_state = 2;
break;
case 'M': /* Reverse Index */
do_escape(cons, c);
break;
default:
cons->c_esc_state = 0;
}
break;
case 2: /* ESC [ seen */
if (c >= '0' && c <= '9') {
if (cons->c_esc_parmp < bufend(cons->c_esc_parmv))
*cons->c_esc_parmp = *cons->c_esc_parmp * 10 + (c-'0');
} else
if (c == ';') {
if (++cons->c_esc_parmp < bufend(cons->c_esc_parmv))
*cons->c_esc_parmp = 0;
} else {
do_escape(cons, c);
}
break;
}
}
/*===========================================================================*
* do_escape *
*===========================================================================*/
PRIVATE void do_escape(cons, c)
register console_t *cons; /* pointer to console struct */
char c; /* next character in escape sequence */
{
int value, n;
unsigned src, dst, count;
/* Some of these things hack on screen RAM, so it had better be up to date */
flush(cons);
if (cons->c_esc_intro == '\0') {
/* Handle a sequence beginning with just ESC */
switch (c) {
case 'M': /* Reverse Index */
if (cons->c_row == 0) {
scroll_screen(cons, SCROLL_DOWN);
} else {
cons->c_row--;
}
flush(cons);
break;
default: break;
}
} else
if (cons->c_esc_intro == '[') {
/* Handle a sequence beginning with ESC [ and parameters */
value = cons->c_esc_parmv[0];
switch (c) {
case 'A': /* ESC [nA moves up n lines */
n = (value == 0 ? 1 : value);
cons->c_row -= n;
flush(cons);
break;
case 'B': /* ESC [nB moves down n lines */
n = (value == 0 ? 1 : value);
cons->c_row += n;
flush(cons);
break;
case 'C': /* ESC [nC moves right n spaces */
n = (value == 0 ? 1 : value);
cons->c_column += n;
flush(cons);
break;
case 'D': /* ESC [nD moves left n spaces */
n = (value == 0 ? 1 : value);
cons->c_column -= n;
flush(cons);
break;
case 'H': /* ESC [m;nH" moves cursor to (m,n) */
cons->c_row = cons->c_esc_parmv[0] - 1;
cons->c_column = cons->c_esc_parmv[1] - 1;
flush(cons);
break;
case 'J': /* ESC [sJ clears in display */
switch (value) {
case 0: /* Clear from cursor to end of screen */
count = scr_size - (cons->c_cur - cons->c_org);
dst = cons->c_cur;
break;
case 1: /* Clear from start of screen to cursor */
count = cons->c_cur - cons->c_org;
dst = cons->c_org;
break;
case 2: /* Clear entire screen */
count = scr_size;
dst = cons->c_org;
break;
default: /* Do nothing */
count = 0;
dst = cons->c_org;
}
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, dst, count);
break;
case 'K': /* ESC [sK clears line from cursor */
switch (value) {
case 0: /* Clear from cursor to end of line */
count = scr_width - cons->c_column;
dst = cons->c_cur;
break;
case 1: /* Clear from beginning of line to cursor */
count = cons->c_column;
dst = cons->c_cur - cons->c_column;
break;
case 2: /* Clear entire line */
count = scr_width;
dst = cons->c_cur - cons->c_column;
break;
default: /* Do nothing */
count = 0;
dst = cons->c_cur;
}
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, dst, count);
break;
case 'L': /* ESC [nL inserts n lines at cursor */
n = value;
if (n < 1) n = 1;
if (n > (scr_lines - cons->c_row))
n = scr_lines - cons->c_row;
src = cons->c_org + cons->c_row * scr_width;
dst = src + n * scr_width;
count = (scr_lines - cons->c_row - n) * scr_width;
vid_vid_copy(src, dst, count);
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, src, n * scr_width);
break;
case 'M': /* ESC [nM deletes n lines at cursor */
n = value;
if (n < 1) n = 1;
if (n > (scr_lines - cons->c_row))
n = scr_lines - cons->c_row;
dst = cons->c_org + cons->c_row * scr_width;
src = dst + n * scr_width;
count = (scr_lines - cons->c_row - n) * scr_width;
vid_vid_copy(src, dst, count);
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, dst + count, n * scr_width);
break;
case '@': /* ESC [n@ inserts n chars at cursor */
n = value;
if (n < 1) n = 1;
if (n > (scr_width - cons->c_column))
n = scr_width - cons->c_column;
src = cons->c_cur;
dst = src + n;
count = scr_width - cons->c_column - n;
vid_vid_copy(src, dst, count);
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, src, n);
break;
case 'P': /* ESC [nP deletes n chars at cursor */
n = value;
if (n < 1) n = 1;
if (n > (scr_width - cons->c_column))
n = scr_width - cons->c_column;
dst = cons->c_cur;
src = dst + n;
count = scr_width - cons->c_column - n;
vid_vid_copy(src, dst, count);
blank_color = cons->c_blank;
mem_vid_copy(BLANK_MEM, dst + count, n);
break;
case 'm': /* ESC [nm enables rendition n */
switch (value) {
case 1: /* BOLD */
if (color) {
/* Can't do bold, so use yellow */
cons->c_attr = (cons->c_attr & 0xf0ff) | 0x0E00;
} else {
/* Set intensity bit */
cons->c_attr |= 0x0800;
}
break;
case 4: /* UNDERLINE */
if (color) {
/* Use light green */
cons->c_attr = (cons->c_attr & 0xf0ff) | 0x0A00;
} else {
cons->c_attr = (cons->c_attr & 0x8900);
}
break;
case 5: /* BLINKING */
if (color) {
/* Use magenta */
cons->c_attr = (cons->c_attr & 0xf0ff) | 0x0500;
} else {
/* Set the blink bit */
cons->c_attr |= 0x8000;
}
break;
case 7: /* REVERSE */
if (color) {
/* Swap fg and bg colors */
cons->c_attr =
((cons->c_attr & 0xf000) >> 4) |
((cons->c_attr & 0x0f00) << 4);
} else
if ((cons->c_attr & 0x7000) == 0) {
cons->c_attr = (cons->c_attr & 0x8800) | 0x7000;
} else {
cons->c_attr = (cons->c_attr & 0x8800) | 0x0700;
}
break;
default: /* COLOR */
if (30 <= value && value <= 37) {
cons->c_attr =
(cons->c_attr & 0xf0ff) |
(ansi_colors[(value - 30)] << 8);
cons->c_blank =
(cons->c_blank & 0xf0ff) |
(ansi_colors[(value - 30)] << 8);
} else
if (40 <= value && value <= 47) {
cons->c_attr =
(cons->c_attr & 0x0fff) |
(ansi_colors[(value - 40)] << 12);
cons->c_blank =
(cons->c_blank & 0x0fff) |
(ansi_colors[(value - 40)] << 12);
} else {
cons->c_attr = cons->c_blank;
}
break;
}
break;
}
}
cons->c_esc_state = 0;
}
/*===========================================================================*
* set_6845 *
*===========================================================================*/
PRIVATE void set_6845(reg, val)
int reg; /* which register pair to set */
unsigned val; /* 16-bit value to set it to */
{
/* Set a register pair inside the 6845.
* Registers 12-13 tell the 6845 where in video ram to start
* Registers 14-15 tell the 6845 where to put the cursor
*/
lock(); /* try to stop h/w loading in-between value */
out_byte(vid_port + INDEX, reg); /* set the index register */
out_byte(vid_port + DATA, (val>>8) & BYTE); /* output high byte */
out_byte(vid_port + INDEX, reg + 1); /* again */
out_byte(vid_port + DATA, val&BYTE); /* output low byte */
unlock();
}
/*===========================================================================*
* beep *
*===========================================================================*/
PRIVATE void beep()
{
/* Making a beeping sound on the speaker (output for CRTL-G).
* This routine works by turning on the bits 0 and 1 in port B of the 8255
* chip that drive the speaker.
*/
message mess;
if (beeping) return;
out_byte(TIMER_MODE, 0xB6); /* set up timer channel 2 (square wave) */
out_byte(TIMER2, BEEP_FREQ & BYTE); /* load low-order bits of frequency */
out_byte(TIMER2, (BEEP_FREQ >> 8) & BYTE); /* now high-order bits */
lock(); /* guard PORT_B from keyboard intr handler */
out_byte(PORT_B, in_byte(PORT_B) | 3); /* turn on beep bits */
unlock();
beeping = TRUE;
mess.m_type = SET_ALARM;
mess.CLOCK_PROC_NR = TTY;
mess.DELTA_TICKS = B_TIME;
mess.FUNC_TO_CALL = (sighandler_t) stop_beep;
sendrec(CLOCK, &mess);
}
/*===========================================================================*
* stop_beep *
*===========================================================================*/
PRIVATE void stop_beep()
{
/* Turn off the beeper by turning off bits 0 and 1 in PORT_B. */
lock(); /* guard PORT_B from keyboard intr handler */
out_byte(PORT_B, in_byte(PORT_B) & ~3);
beeping = FALSE;
unlock();
}
/*===========================================================================*
* scr_init *
*===========================================================================*/
PUBLIC void scr_init(tp)
tty_t *tp;
{
/* Initialize the screen driver. */
console_t *cons;
phys_bytes vid_base;
u16_t bios_crtbase;
int line;
unsigned page_size;
/* Associate console and TTY. */
line = tp - &tty_table[0];
if (line >= nr_cons) return;
cons = &cons_table[line];
cons->c_tty = tp;
tp->tty_priv = cons;
/* Initialize the keyboard driver. */
kb_init(tp);
/* Output functions. */
tp->tty_devwrite = cons_write;
tp->tty_echo = cons_echo;
/* Get the BIOS parameters that tells the VDU I/O base register. */
phys_copy(0x463L, vir2phys(&bios_crtbase), 2L);
vid_port = bios_crtbase;
if (color) {
vid_base = COLOR_BASE;
vid_size = COLOR_SIZE;
} else {
vid_base = MONO_BASE;
vid_size = MONO_SIZE;
}
if (ega) vid_size = EGA_SIZE;
wrap = !ega;
vid_seg = protected_mode ? VIDEO_SELECTOR : physb_to_hclick(vid_base);
init_dataseg(&gdt[VIDEO_INDEX], vid_base, (phys_bytes) vid_size,
TASK_PRIVILEGE);
vid_size >>= 1; /* word count */
vid_mask = vid_size - 1;
/* There can be as many consoles as video memory allows. */
nr_cons = vid_size / scr_size;
if (nr_cons > NR_CONS) nr_cons = NR_CONS;
if (nr_cons > 1) wrap = 0;
page_size = vid_size / nr_cons;
cons->c_start = line * page_size;
cons->c_limit = cons->c_start + page_size;
cons->c_org = cons->c_start;
cons->c_attr = cons->c_blank = BLANK_COLOR;
/* Clear the screen. */
blank_color = BLANK_COLOR;
mem_vid_copy(BLANK_MEM, cons->c_start, scr_size);
select_console(0);
}
/*===========================================================================*
* putk *
*===========================================================================*/
PUBLIC void putk(c)
int c; /* character to print */
{
/* This procedure is used by the version of printf() that is linked with
* the kernel itself. The one in the library sends a message to FS, which is
* not what is needed for printing within the kernel. This version just queues
* the character and starts the output.
*/
if (c != 0) {
if (c == '\n') putk('\r');
out_char(&cons_table[0], (int) c);
} else {
flush(&cons_table[0]);
}
}
/*===========================================================================*
* toggle_scroll *
*===========================================================================*/
PUBLIC void toggle_scroll()
{
/* Toggle between hardware and software scroll. */
cons_org0();
softscroll = !softscroll;
printf("%sware scrolling enabled.\n", softscroll ? "Soft" : "Hard");
}
/*===========================================================================*
* cons_stop *
*===========================================================================*/
PUBLIC void cons_stop()
{
/* Prepare for halt or reboot. */
cons_org0();
softscroll = 1;
select_console(0);
cons_table[0].c_attr = cons_table[0].c_blank = BLANK_COLOR;
}
/*===========================================================================*
* cons_org0 *
*===========================================================================*/
PRIVATE void cons_org0()
{
/* Scroll video memory back to put the origin at 0. */
int cons_line;
console_t *cons;
unsigned n;
for (cons_line = 0; cons_line < nr_cons; cons_line++) {
cons = &cons_table[cons_line];
while (cons->c_org > cons->c_start) {
n = vid_size - scr_size; /* amount of unused memory */
if (n > cons->c_org - cons->c_start)
n = cons->c_org - cons->c_start;
vid_vid_copy(cons->c_org, cons->c_org - n, scr_size);
cons->c_org -= n;
}
flush(cons);
}
select_console(current);
}
/*===========================================================================*
* select_console *
*===========================================================================*/
PUBLIC void select_console(int cons_line)
{
/* Set the current console to console number 'cons_line'. */
if (cons_line < 0 || cons_line >= nr_cons) return;
current = cons_line;
curcons = &cons_table[cons_line];
set_6845(VID_ORG, curcons->c_org);
set_6845(CURSOR, curcons->c_cur);
}
/*===========================================================================*
* con_loadfont *
*===========================================================================*/
PUBLIC int con_loadfont(user_phys)
phys_bytes user_phys;
{
/* Load a font into the EGA or VGA adapter. */
static struct sequence seq1[7] = {
{ GA_SEQUENCER_INDEX, 0x00, 0x01 },
{ GA_SEQUENCER_INDEX, 0x02, 0x04 },
{ GA_SEQUENCER_INDEX, 0x04, 0x07 },
{ GA_SEQUENCER_INDEX, 0x00, 0x03 },
{ GA_GRAPHICS_INDEX, 0x04, 0x02 },
{ GA_GRAPHICS_INDEX, 0x05, 0x00 },
{ GA_GRAPHICS_INDEX, 0x06, 0x00 },
};
static struct sequence seq2[7] = {
{ GA_SEQUENCER_INDEX, 0x00, 0x01 },
{ GA_SEQUENCER_INDEX, 0x02, 0x03 },
{ GA_SEQUENCER_INDEX, 0x04, 0x03 },
{ GA_SEQUENCER_INDEX, 0x00, 0x03 },
{ GA_GRAPHICS_INDEX, 0x04, 0x00 },
{ GA_GRAPHICS_INDEX, 0x05, 0x10 },
{ GA_GRAPHICS_INDEX, 0x06, 0 },
};
seq2[6].value= color ? 0x0E : 0x0A;
if (!ega) return(ENOTTY);
lock();
ga_program(seq1); /* bring font memory into view */
phys_copy(user_phys, (phys_bytes)GA_VIDEO_ADDRESS, (phys_bytes)GA_FONT_SIZE);
ga_program(seq2); /* restore */
unlock();
return(OK);
}
/*===========================================================================*
* ga_program *
*===========================================================================*/
PRIVATE void ga_program(seq)
struct sequence *seq;
{
int len= 7;
do {
out_byte(seq->index, seq->port);
out_byte(seq->index+1, seq->value);
seq++;
} while (--len > 0);
}