/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ /* * expand gzipped boot loader appended to this binary and execute it. * * due to Russ Cox, rsc@swtch.com. * see http://plan9.bell-labs.com/wiki/plan9/Replacing_9load */#include <u.h>#include <libc.h>#include <a.out.h>#include <flate.h>#include "mem.h"#include "expand.h" #include "inflate.guts.c" #define KB		1024#define MB		(1024*1024) extern char edata[]; /* ldecomp.s */void mb586(void);void splhi(void);void wbinvd(void); /* inflate.guts.c */int gunzip(uchar*, int, uchar*, int); int isexec(void*);int isgzip(uchar*);void run(void*); #pragma varargck type "d" ulong#pragma varargck type "x" ulong static uchar *kernel = (uchar*)Bootkernaddr;static char *dbrk = (char*)Mallocbase; ulongswap(ulong p){	return p<<24 | p>>24 | (p<<8)&0x00FF0000 | (p>>8)&0x0000FF00;} enum {	/* keyboard controller ports & cmds */	Data=		0x60,		/* data port */	Status=		0x64,		/* status port */	 Inready=	0x01,		/*  input character ready */	 Outbusy=	0x02,		/*  output busy */	Cmd=		0x64,		/* command port (write only) */ 	/* system control port a */	Sysctla=	0x92,	 Sysctlreset=	1<<0,	 Sysctla20ena=	1<<1,}; static intisa20on(void){	int r;	ulong o;	ulong *zp, *mb1p; 	zp = 0;	mb1p = (ulong *)MB;	o = *zp; 	*zp = 0x1234;	*mb1p = 0x8765;	mb586();	wbinvd();	r = *zp != *mb1p; 	*zp = o;	return r;} static voiddelay(uint ms)				/* approximate */{	int i; 	while(ms-- > 0)		for(i = 1000*1000; i > 0; i--)			;} static intkbdinit(void){	int c, try; 	/* wait for a quiescent controller */	try = 500;			/* was 1000 */	while(try-- > 0 && (c = inb(Status)) & (Outbusy | Inready)) {		if(c & Inready)			inb(Data);		delay(1);	}	return try <= 0? -1: 0;} /* *  wait for output no longer busy (but not forever, *  there might not be a keyboard controller). */static voidoutready(void){	int i; 	for (i = 1000; i > 0 && inb(Status) & Outbusy; i--)		delay(1);} /* *  ask 8042 to enable the use of address bit 20 */inti8042a20(void){	if (kbdinit() < 0)		return -1;	outready();	outb(Cmd, 0xD1);	outready();	outb(Data, 0xDF);	outready();	return 0;} voida20init(void){	int b; 	if (isa20on())		return;	if (i8042a20() < 0) {		/* original method, via kbd ctlr */		/* newer method, last resort */		b = inb(Sysctla);		if (!(b & Sysctla20ena))			outb(Sysctla, (b & ~Sysctlreset) | Sysctla20ena);	}	if (!isa20on())		print("a20 didn't come on!\n");} void_main(void){	int ksize;	Exec *exec; 	splhi();	a20init();		/* don't wrap addresses at 1MB boundaries */	ksize = Lowmemsz - (ulong)edata;	/* payload size */	memmove(kernel, edata, ksize);	memset(edata, 0, end - edata); 	cgainit();	if(isgzip(kernel)) {		print("gz...");		memmove((uchar*)Unzipbuf, kernel, ksize); 		/* we have to uncompress the entire kernel to get OK status */		if(gunzip(kernel, Bootkernmax, (uchar*)Unzipbuf, ksize) < 0){			print("gzip failed.");			exits(0);		}	}	if(isexec(kernel))		run(kernel); 	exec = (Exec *)kernel;	print("unrecognized program; magic # 0x%x\n", swap(exec->magic));	exits(0);} intisexec(void *v){	Exec *exec; 	exec = v;	return swap(exec->magic) == I_MAGIC || swap(exec->magic) == S_MAGIC;} voidrun(void *v){	ulong entry, text, data;	uchar *base;	Exec *exec; 	base = v;	exec = v;	entry = swap(exec->entry) & ~KSEGM;	text = swap(exec->text);	data = swap(exec->data);	/*	 * align data segment on the expected page boundary.	 * sizeof(Exec)+text is offset from base to data segment.	 */	memmove(base+PGROUND(sizeof(Exec)+text), base+sizeof(Exec)+text, data); 	print("starting protected-mode loader at 0x%x\n", entry);	((void(*)(void))entry)(); 	print("exec failed");	exits(0);} intisgzip(uchar *p){	return p[0] == 0x1F && p[1] == 0x8B;} void*malloc(ulong n){	void *v; 	v = dbrk;	dbrk += ROUND(n, BY2WD);	return v;} voidfree(void*){} voidputs(char *s){	for(; *s; s++)		cgaputc(*s);} intprint(char *fmt, ...){	int sign;	long d;	ulong x;	char *p, *s, buf[20];	va_list arg;	static char *hex = "0123456789abcdef"; 	va_start(arg, fmt);	for(p = fmt; *p; p++){		if(*p != '%') {			cgaputc(*p);			continue;		}		SET(s);		switch(*++p){		case 'p':		case 'x':			x = va_arg(arg, ulong);			if(x == 0){				s = "0";				break;			}			s = buf+sizeof buf;			*--s = 0;			while(x > 0){				*--s = hex[x&15];				x /= 16;			}			if(s == buf+sizeof buf)				*--s = '0';			break;		case 'd':			d = va_arg(arg, ulong);			if(d == 0){				s = "0";				break;			}			if(d < 0){				d = -d;				sign = -1;			}else				sign = 1;			s = buf+sizeof buf;			*--s = 0;			while(d > 0){				*--s = (d%10)+'0';				d /= 10;			}			if(sign < 0)				*--s = '-';			break;		case 's':			s = va_arg(arg, char*);			break;		case 0:			return 0;		}		puts(s);	}	return 0;} voidexits(char*){	for(;;)		;}