lib.c

系统启动时检测内存状况的软件C代码

/* lib.c - MemTest-86  Version 3.0
 *
 * Released under version 2 of the Gnu Public License.
 * By Chris Brady, [e-mail]
 */
#include "io.h"
#include "serial.h"
#include "test.h"
#include "config.h"
#include "screen_buffer.h"

extern int fast_mode;

int slock = 0, lsr = 0;
short serial_cons = SERIAL_CONSOLE_DEFAULT;
char buf[18];

struct ascii_map_str {
	int ascii;
	int keycode;
};

char *codes[] = {
	"  Divide",
	"   Debug",
	"     NMI",
	"  Brkpnt",
	"Overflow",
	"   Bound",
	"  Inv_Op",
	" No_Math",
	"Double_Fault",
	"Seg_Over",
	" Inv_TSS",
	"  Seg_NP",
	"Stack_Fault",
	"Gen_Prot",
	"Page_Fault",
	"   Resvd",
	"     FPE",
	"Alignment",
	" Mch_Chk",
	"SIMD FPE"
};

struct eregs {
	ulong esp;
	ulong ebp;
	ulong esi;
	ulong edi;
	ulong edx;
	ulong ecx;
	ulong ebx;
	ulong eax;
	ulong vect;
	ulong code;
	ulong eip;
	ulong cs;
	ulong eflag;
};

int memcmp(const void *s1, const void *s2, ulong count)
{
	const unsigned char *src1 = s1, *src2 = s2;
	int i;
	for(i = 0; i < count; i++) {
		if (src1[i] != src2[i]) {
			return (int)src1[i] - (int)src2[i];
		}
	}
	return 0;
}

void *memmove(void *dest, const void *src, ulong n)
{
	long i;
	char *d = (char *)dest, *s = (char *)src;

	/* If src == dest do nothing */
	if (dest < src) {
		for(i = 0; i < n; i++) {
			d[i] = s[i];
		}
	}
	else if (dest > src) {
		for(i = n -1; i >= 0; i--) {
			d[i] = s[i];
		}
	}
	return dest;
}
/*
 * Scroll the error message area of the screen as needed
 * Starts at line LINE_SCROLL and ends at line 23
 */
void scroll(void)
{
	int i, j;
	char *s, tmp;

	/* Only scroll if at the bottom of the screen */
	if (v->msg_line < 23) {
		v->msg_line++;
	} else {
		/* If scroll lock is on, loop till it is cleared */
		while (slock) {
			check_input();
		}
		for (i=LINE_SCROLL; i<23; i++) {
			s = (char *)(SCREEN_ADR + ((i+1) * 160));
			for (j=0; j<160; j+=2, s+=2) {
				*(s-160) = *s;
				tmp = get_scrn_buf(i+1, j/2);
				set_scrn_buf(i, j/2, tmp);
			}
		}
		/* Clear the newly opened line */
		s = (char *)(SCREEN_ADR + (23 * 160));
		for (j=0; j<80; j++) {
			*s = ' ';
			set_scrn_buf(23, j, ' ');
			s += 2;
		}
		tty_print_region(LINE_SCROLL, 0, 23, 79);
	}
}

/*
 * Print characters on screen
 */
void cprint(int y, int x, const char *text)
{
	register int i;
	char *dptr;

	dptr = (char *)(SCREEN_ADR + (160*y) + (2*x));
	for (i=0; text[i]; i++) {
		*dptr = text[i];
		dptr += 2;
	}
	tty_print_line(y, x, text);
}

void itoa(char s[], int n)
{
	int i, sign;

	if((sign = n) < 0)
		n = -n;
	i=0;
	do {
		s[i++] = n % 10 + '0';
	} while ((n /= 10) > 0);
	if(sign < 0)
		s[i++] = '-';
	s[i] = '\0';
	reverse(s);
}

void reverse(char s[])
{
	int c, i, j;
	for(j = 0; s[j] != 0; j++)
		;

	for(i=0, j = j - 1; i < j; i++, j--) {
		c = s[i];
		s[i] = s[j];
		s[j] = c;
	}
}

/*
 * Print a people friendly address
 */
void aprint(int y, int x, ulong page)
{
	/* page is in multiples of 4K */
	if ((page << 2) < 9999) {
		dprint(y, x, page << 2, 4, 0);
		cprint(y, x+4, "K");
	}
	else if ((page >>8) < 9999) {
		dprint(y, x, (page  + (1 << 7)) >> 8, 4, 0);
		cprint(y, x+4, "M");
	}
	else if ((page >>18) < 9999) {
		dprint(y, x, (page + (1 << 17)) >> 18, 4, 0);
		cprint(y, x+4, "G");
	}
	else {
		dprint(y, x, (page + (1 << 27)) >> 28, 4, 0);
		cprint(y, x+4, "T");
	}
}

/*
 * Print a decimal number on screen
 */
void dprint(int y, int x, ulong val, int len, int right)
{
	ulong j, k;
	int i, flag=0;

	if (val > 999999999 || len > 9) {
		return;
	}
	for(i=0, j=1; i<len-1; i++) {
		j *= 10;
	}
	if (!right) {
		for (i=0; j>0; j/=10) {
			k = val/j;
			if (k > 9) {
				j *= 100;
				continue;
			}
			if (flag || k || j == 1) {
				buf[i++] = k + '0';
				flag++;
			} else {
				buf[i++] = ' ';
			}
			val -= k * j;
		}
	} else {
		for(i=0; i<len; j/=10) {
			if (j) {
				k = val/j;
					if (k > 9) {
					j *= 100;
					len++;
					continue;
				}
				if (k == 0 && flag == 0) {
					continue;
				}
				buf[i++] = k + '0';
				val -= k * j;
			} else {
				if (flag == 0 &&  i < len-1) {
					buf[i++] = '0';
				} else {
					buf[i++] = ' ';
				}
			}
			flag++;
		}
	}
	buf[i] = 0;
	cprint(y,x,buf);
}

/*
 * Print a hex number on screen at least digits long
 */
void hprint2(int y,int x, unsigned long val, int digits)
{
        unsigned long j;
        int i, idx, flag = 0;

        for (i=0, idx=0; i<8; i++) {
                j = val >> (28 - (4 * i));
                j &= 0xf;
                if (j < 10) {
                        if (flag || j || i == 7) {
                                buf[idx++] = j + '0';
                                flag++;
                        } else {
                                buf[idx++] = '0';
                        }
                } else {
                        buf[idx++] = j + 'a' - 10;
                        flag++;
                }
        }
        if (digits > 8) {
                digits = 8;
        }
        if (flag > digits) {
                digits = flag;
        }
        buf[idx] = 0;
        cprint(y,x,buf + (idx - digits));
}

/*
 * Print a hex number on screen exactly digits long
 */
void hprint3(int y,int x, unsigned long val, int digits)
{
	unsigned long j;
	int i, idx, flag = 0;


	for (i=0, idx=0; i<digits; i++) {
		j = 0xf & val;
		val /= 16;

		if (j < 10) {
			if (flag || j || i == 7) {
				buf[digits - ++idx] = j + '0';
				flag++;
			} else {
				buf[digits - ++idx] = '0';
			}
		} else {
			buf[digits - ++idx] = j + 'a' - 10;
			flag++;
		}
	}
	buf[idx] = 0;
	cprint(y,x,buf);
}

/*
 * Print a hex number on screen
 */
void hprint(int y, int x, unsigned long val)
{
	return hprint2(y, x, val, 8);
}

/*
 * Print an address in 0000m0000k0000 notation
 */
void xprint(int y,int x, ulong val)
{
	ulong j;

	j = (val & 0xffc00000) >> 20;
	dprint(y, x, j, 4, 0);
	cprint(y, x+4, "m");
	j = (val & 0xffc00) >> 10;
	dprint(y, x+5, j, 4, 0);
	cprint(y, x+9, "k");
	j = val & 0x3ff;
	dprint(y, x+10, j, 4, 0);
}

/* Handle an interrupt */
void inter(struct eregs *trap_regs)
{
	int i, line;
	unsigned char *pp;
	ulong address = 0;

	/* Get the page fault address */
	if (trap_regs->vect == 14) {
		__asm__("movl %%cr2,%0":"=r" (address));
	}
#ifdef PARITY_MEM

	/* Check for a parity error */
	if (trap_regs->vect == 2) {
		parity_err(trap_regs->edi, trap_regs->esi);
		return;
	}
#endif

	/* clear scrolling region */
	pp=(unsigned char *)(SCREEN_ADR+(2*80*(LINE_SCROLL-2)));
	for(i=0; i<2*80*(24-LINE_SCROLL-2); i++, pp+=2) {
		*pp = ' ';
	}
	line = LINE_SCROLL-2;

	cprint(line, 0, "Unexpected Interrupt - Halting");
	cprint(line+2, 0, " Type: ");
	if (trap_regs->vect <= 19) {
		cprint(line+2, 7, codes[trap_regs->vect]);
	} else {
		hprint(line+2, 7, trap_regs->vect);
	}
	cprint(line+3, 0, "   PC: ");
	hprint(line+3, 7, trap_regs->eip);
	cprint(line+4, 0, "   CS: ");
	hprint(line+4, 7, trap_regs->cs);
	cprint(line+5, 0, "Eflag: ");
	hprint(line+5, 7, trap_regs->eflag);
	cprint(line+6, 0, " Code: ");
	hprint(line+6, 7, trap_regs->code);
	if (trap_regs->vect == 14) {
		/* Page fault address */
		cprint(line+7, 0, " Addr: ");
		hprint(line+7, 7, address);
	}

	cprint(line+2, 20, "eax: ");
	hprint(line+2, 25, trap_regs->eax);
	cprint(line+3, 20, "ebx: ");
	hprint(line+3, 25, trap_regs->ebx);
	cprint(line+4, 20, "ecx: ");
	hprint(line+4, 25, trap_regs->ecx);
	cprint(line+5, 20, "edx: ");
	hprint(line+5, 25, trap_regs->edx);
	cprint(line+6, 20, "edi: ");
	hprint(line+6, 25, trap_regs->edi);
	cprint(line+7, 20, "esi: ");
	hprint(line+7, 25, trap_regs->esi);
	cprint(line+8, 20, "ebp: ");
	hprint(line+8, 25, trap_regs->ebp);
	cprint(line+9, 20, "esp: ");
	hprint(line+9, 25, trap_regs->esp);

	cprint(line+1, 38, "Stack:");
	for (i=0; i<12; i++) {
		hprint(line+2+i, 38, trap_regs->esp+(4*i));
		hprint(line+2+i, 47, *(ulong*)(trap_regs->esp+(4*i)));
		hprint(line+2+i, 57, trap_regs->esp+(4*(i+12)));
		hprint(line+2+i, 66, *(ulong*)(trap_regs->esp+(4*(i+12))));
	}

	cprint(line+11, 0, "CS:EIP:                          ");
	pp = (unsigned char *)trap_regs->eip;
	for(i = 0; i < 10; i++) {
		hprint2(line+11, 8+(3*i), pp[i], 2);
	}

	while(1) {
		check_input();
	}
}

void set_cache(int val)
{
	extern struct cpu_ident cpu_id;
	/* 386's don't have a cache */
	if ((cpu_id.cpuid < 1) && (cpu_id.type == 3)) {
		cprint(LINE_INFO, COL_CACHE, "none");
		return;
	}
	switch(val) {
	case 0:
		cache_off();
		cprint(LINE_INFO, COL_CACHE, "off");
		break;
	case 1:
		cache_on();
		cprint(LINE_INFO, COL_CACHE, " on");
		break;
	}
}

int get_key() {
	int c;

	c = inb(0x64);
	if ((c & 1) == 0) {
		if (serial_cons) {
			int comstat;
			comstat = serial_echo_inb(UART_LSR);
			if (comstat & UART_LSR_DR) {
				c = serial_echo_inb(UART_RX);
				/* Pressing '.' has same effect as 'c'
				   on a keyboard.
				   Oct 056   Dec 46   Hex 2E   Ascii .
				*/
				return (ascii_to_keycode(c));
			}
		}
		return(0);
	}
	c = inb(0x60);
	return((c));
}

void check_input(void)
{
	unsigned char c;

	if ((c = get_key())) {
		switch(c & 0x7f) {
		case 1:
			/* "ESC" key was pressed, bail out.  */
			cprint(LINE_RANGE, COL_MID+23, "Halting... ");

			/* tell the BIOS to do a warm start */
			*((unsigned short *)0x472) = 0x1234;
			outb(0xfe,0x64);
			break;
		case 46:
			/* c - Configure */
			get_config();
			break;
		case 28:
			/* CR - clear scroll lock */
			slock = 0;