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-rw-r--r--linux/kernel/console.c550
1 files changed, 550 insertions, 0 deletions
diff --git a/linux/kernel/console.c b/linux/kernel/console.c
new file mode 100644
index 0000000..9e00b31
--- /dev/null
+++ b/linux/kernel/console.c
@@ -0,0 +1,550 @@
+/*
+ * console.c
+ *
+ * This module implements the console io functions
+ * 'void con_init(void)'
+ * 'void con_write(struct tty_queue * queue)'
+ * Hopefully this will be a rather complete VT102 implementation.
+ *
+ */
+
+/*
+ * NOTE!!! We sometimes disable and enable interrupts for a short while
+ * (to put a word in video IO), but this will work even for keyboard
+ * interrupts. We know interrupts aren't enabled when getting a keyboard
+ * interrupt, as we use trap-gates. Hopefully all is well.
+ */
+
+#include <linux/sched.h>
+#include <linux/tty.h>
+#include <asm/io.h>
+#include <asm/system.h>
+
+#define SCREEN_START 0xb8000
+#define SCREEN_END 0xc0000
+#define LINES 25
+#define COLUMNS 80
+#define NPAR 16
+
+extern void keyboard_interrupt(void);
+
+static unsigned long origin=SCREEN_START;
+static unsigned long scr_end=SCREEN_START+LINES*COLUMNS*2;
+static unsigned long pos;
+static unsigned long x,y;
+static unsigned long top=0,bottom=LINES;
+static unsigned long lines=LINES,columns=COLUMNS;
+static unsigned long state=0;
+static unsigned long npar,par[NPAR];
+static unsigned long ques=0;
+static unsigned char attr=0x07;
+
+/*
+ * this is what the terminal answers to a ESC-Z or csi0c
+ * query (= vt100 response).
+ */
+#define RESPONSE "\033[?1;2c"
+
+static inline void gotoxy(unsigned int new_x,unsigned int new_y)
+{
+ if (new_x>=columns || new_y>=lines)
+ return;
+ x=new_x;
+ y=new_y;
+ pos=origin+((y*columns+x)<<1);
+}
+
+static inline void set_origin(void)
+{
+ cli();
+ outb_p(12,0x3d4);
+ outb_p(0xff&((origin-SCREEN_START)>>9),0x3d5);
+ outb_p(13,0x3d4);
+ outb_p(0xff&((origin-SCREEN_START)>>1),0x3d5);
+ sti();
+}
+
+static void scrup(void)
+{
+ if (!top && bottom==lines) {
+ origin += columns<<1;
+ pos += columns<<1;
+ scr_end += columns<<1;
+ if (scr_end>SCREEN_END) {
+ __asm__("cld\n\t"
+ "rep\n\t"
+ "movsl\n\t"
+ "movl _columns,%1\n\t"
+ "rep\n\t"
+ "stosw"
+ ::"a" (0x0720),
+ "c" ((lines-1)*columns>>1),
+ "D" (SCREEN_START),
+ "S" (origin)
+ :"cx","di","si");
+ scr_end -= origin-SCREEN_START;
+ pos -= origin-SCREEN_START;
+ origin = SCREEN_START;
+ } else {
+ __asm__("cld\n\t"
+ "rep\n\t"
+ "stosl"
+ ::"a" (0x07200720),
+ "c" (columns>>1),
+ "D" (scr_end-(columns<<1))
+ :"cx","di");
+ }
+ set_origin();
+ } else {
+ __asm__("cld\n\t"
+ "rep\n\t"
+ "movsl\n\t"
+ "movl _columns,%%ecx\n\t"
+ "rep\n\t"
+ "stosw"
+ ::"a" (0x0720),
+ "c" ((bottom-top-1)*columns>>1),
+ "D" (origin+(columns<<1)*top),
+ "S" (origin+(columns<<1)*(top+1))
+ :"cx","di","si");
+ }
+}
+
+static void scrdown(void)
+{
+ __asm__("std\n\t"
+ "rep\n\t"
+ "movsl\n\t"
+ "addl $2,%%edi\n\t" /* %edi has been decremented by 4 */
+ "movl _columns,%%ecx\n\t"
+ "rep\n\t"
+ "stosw"
+ ::"a" (0x0720),
+ "c" ((bottom-top-1)*columns>>1),
+ "D" (origin+(columns<<1)*bottom-4),
+ "S" (origin+(columns<<1)*(bottom-1)-4)
+ :"ax","cx","di","si");
+}
+
+static void lf(void)
+{
+ if (y+1<bottom) {
+ y++;
+ pos += columns<<1;
+ return;
+ }
+ scrup();
+}
+
+static void ri(void)
+{
+ if (y>top) {
+ y--;
+ pos -= columns<<1;
+ return;
+ }
+ scrdown();
+}
+
+static void cr(void)
+{
+ pos -= x<<1;
+ x=0;
+}
+
+static void del(void)
+{
+ if (x) {
+ pos -= 2;
+ x--;
+ *(unsigned short *)pos = 0x0720;
+ }
+}
+
+static void csi_J(int par)
+{
+ long count __asm__("cx");
+ long start __asm__("di");
+
+ switch (par) {
+ case 0: /* erase from cursor to end of display */
+ count = (scr_end-pos)>>1;
+ start = pos;
+ break;
+ case 1: /* erase from start to cursor */
+ count = (pos-origin)>>1;
+ start = origin;
+ break;
+ case 2: /* erase whole display */
+ count = columns*lines;
+ start = origin;
+ break;
+ default:
+ return;
+ }
+ __asm__("cld\n\t"
+ "rep\n\t"
+ "stosw\n\t"
+ ::"c" (count),
+ "D" (start),"a" (0x0720)
+ :"cx","di");
+}
+
+static void csi_K(int par)
+{
+ long count __asm__("cx");
+ long start __asm__("di");
+
+ switch (par) {
+ case 0: /* erase from cursor to end of line */
+ if (x>=columns)
+ return;
+ count = columns-x;
+ start = pos;
+ break;
+ case 1: /* erase from start of line to cursor */
+ start = pos - (x<<1);
+ count = (x<columns)?x:columns;
+ break;
+ case 2: /* erase whole line */
+ start = pos - (x<<1);
+ count = columns;
+ break;
+ default:
+ return;
+ }
+ __asm__("cld\n\t"
+ "rep\n\t"
+ "stosw\n\t"
+ ::"c" (count),
+ "D" (start),"a" (0x0720)
+ :"cx","di");
+}
+
+void csi_m(void)
+{
+ int i;
+
+ for (i=0;i<=npar;i++)
+ switch (par[i]) {
+ case 0:attr=0x07;break;
+ case 1:attr=0x0f;break;
+ case 4:attr=0x0f;break;
+ case 7:attr=0x70;break;
+ case 27:attr=0x07;break;
+ }
+}
+
+static inline void set_cursor(void)
+{
+ cli();
+ outb_p(14,0x3d4);
+ outb_p(0xff&((pos-SCREEN_START)>>9),0x3d5);
+ outb_p(15,0x3d4);
+ outb_p(0xff&((pos-SCREEN_START)>>1),0x3d5);
+ sti();
+}
+
+static void respond(struct tty_struct * tty)
+{
+ char * p = RESPONSE;
+
+ cli();
+ while (*p) {
+ PUTCH(*p,tty->read_q);
+ p++;
+ }
+ sti();
+ copy_to_cooked(tty);
+}
+
+static void insert_char(void)
+{
+ int i=x;
+ unsigned short tmp,old=0x0720;
+ unsigned short * p = (unsigned short *) pos;
+
+ while (i++<columns) {
+ tmp=*p;
+ *p=old;
+ old=tmp;
+ p++;
+ }
+}
+
+static void insert_line(void)
+{
+ int oldtop,oldbottom;
+
+ oldtop=top;
+ oldbottom=bottom;
+ top=y;
+ bottom=lines;
+ scrdown();
+ top=oldtop;
+ bottom=oldbottom;
+}
+
+static void delete_char(void)
+{
+ int i;
+ unsigned short * p = (unsigned short *) pos;
+
+ if (x>=columns)
+ return;
+ i = x;
+ while (++i < columns) {
+ *p = *(p+1);
+ p++;
+ }
+ *p=0x0720;
+}
+
+static void delete_line(void)
+{
+ int oldtop,oldbottom;
+
+ oldtop=top;
+ oldbottom=bottom;
+ top=y;
+ bottom=lines;
+ scrup();
+ top=oldtop;
+ bottom=oldbottom;
+}
+
+static void csi_at(int nr)
+{
+ if (nr>columns)
+ nr=columns;
+ else if (!nr)
+ nr=1;
+ while (nr--)
+ insert_char();
+}
+
+static void csi_L(int nr)
+{
+ if (nr>lines)
+ nr=lines;
+ else if (!nr)
+ nr=1;
+ while (nr--)
+ insert_line();
+}
+
+static void csi_P(int nr)
+{
+ if (nr>columns)
+ nr=columns;
+ else if (!nr)
+ nr=1;
+ while (nr--)
+ delete_char();
+}
+
+static void csi_M(int nr)
+{
+ if (nr>lines)
+ nr=lines;
+ else if (!nr)
+ nr=1;
+ while (nr--)
+ delete_line();
+}
+
+static int saved_x=0;
+static int saved_y=0;
+
+static void save_cur(void)
+{
+ saved_x=x;
+ saved_y=y;
+}
+
+static void restore_cur(void)
+{
+ x=saved_x;
+ y=saved_y;
+ pos=origin+((y*columns+x)<<1);
+}
+
+void con_write(struct tty_struct * tty)
+{
+ int nr;
+ char c;
+
+ nr = CHARS(tty->write_q);
+ while (nr--) {
+ GETCH(tty->write_q,c);
+ switch(state) {
+ case 0:
+ if (c>31 && c<127) {
+ if (x>=columns) {
+ x -= columns;
+ pos -= columns<<1;
+ lf();
+ }
+ __asm__("movb _attr,%%ah\n\t"
+ "movw %%ax,%1\n\t"
+ ::"a" (c),"m" (*(short *)pos)
+ :"ax");
+ pos += 2;
+ x++;
+ } else if (c==27)
+ state=1;
+ else if (c==10 || c==11 || c==12)
+ lf();
+ else if (c==13)
+ cr();
+ else if (c==ERASE_CHAR(tty))
+ del();
+ else if (c==8) {
+ if (x) {
+ x--;
+ pos -= 2;
+ }
+ } else if (c==9) {
+ c=8-(x&7);
+ x += c;
+ pos += c<<1;
+ if (x>columns) {
+ x -= columns;
+ pos -= columns<<1;
+ lf();
+ }
+ c=9;
+ }
+ break;
+ case 1:
+ state=0;
+ if (c=='[')
+ state=2;
+ else if (c=='E')
+ gotoxy(0,y+1);
+ else if (c=='M')
+ ri();
+ else if (c=='D')
+ lf();
+ else if (c=='Z')
+ respond(tty);
+ else if (x=='7')
+ save_cur();
+ else if (x=='8')
+ restore_cur();
+ break;
+ case 2:
+ for(npar=0;npar<NPAR;npar++)
+ par[npar]=0;
+ npar=0;
+ state=3;
+ if (ques=(c=='?'))
+ break;
+ case 3:
+ if (c==';' && npar<NPAR-1) {
+ npar++;
+ break;
+ } else if (c>='0' && c<='9') {
+ par[npar]=10*par[npar]+c-'0';
+ break;
+ } else state=4;
+ case 4:
+ state=0;
+ switch(c) {
+ case 'G': case '`':
+ if (par[0]) par[0]--;
+ gotoxy(par[0],y);
+ break;
+ case 'A':
+ if (!par[0]) par[0]++;
+ gotoxy(x,y-par[0]);
+ break;
+ case 'B': case 'e':
+ if (!par[0]) par[0]++;
+ gotoxy(x,y+par[0]);
+ break;
+ case 'C': case 'a':
+ if (!par[0]) par[0]++;
+ gotoxy(x+par[0],y);
+ break;
+ case 'D':
+ if (!par[0]) par[0]++;
+ gotoxy(x-par[0],y);
+ break;
+ case 'E':
+ if (!par[0]) par[0]++;
+ gotoxy(0,y+par[0]);
+ break;
+ case 'F':
+ if (!par[0]) par[0]++;
+ gotoxy(0,y-par[0]);
+ break;
+ case 'd':
+ if (par[0]) par[0]--;
+ gotoxy(x,par[0]);
+ break;
+ case 'H': case 'f':
+ if (par[0]) par[0]--;
+ if (par[1]) par[1]--;
+ gotoxy(par[1],par[0]);
+ break;
+ case 'J':
+ csi_J(par[0]);
+ break;
+ case 'K':
+ csi_K(par[0]);
+ break;
+ case 'L':
+ csi_L(par[0]);
+ break;
+ case 'M':
+ csi_M(par[0]);
+ break;
+ case 'P':
+ csi_P(par[0]);
+ break;
+ case '@':
+ csi_at(par[0]);
+ break;
+ case 'm':
+ csi_m();
+ break;
+ case 'r':
+ if (par[0]) par[0]--;
+ if (!par[1]) par[1]=lines;
+ if (par[0] < par[1] &&
+ par[1] <= lines) {
+ top=par[0];
+ bottom=par[1];
+ }
+ break;
+ case 's':
+ save_cur();
+ break;
+ case 'u':
+ restore_cur();
+ break;
+ }
+ }
+ }
+ set_cursor();
+}
+
+/*
+ * void con_init(void);
+ *
+ * This routine initalizes console interrupts, and does nothing
+ * else. If you want the screen to clear, call tty_write with
+ * the appropriate escape-sequece.
+ */
+void con_init(void)
+{
+ register unsigned char a;
+
+ gotoxy(*(unsigned char *)(0x90000+510),*(unsigned char *)(0x90000+511));
+ set_trap_gate(0x21,&keyboard_interrupt);
+ outb_p(inb_p(0x21)&0xfd,0x21);
+ a=inb_p(0x61);
+ outb_p(a|0x80,0x61);
+ outb(a,0x61);
+}
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