misc.c

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/*
 * misc.c
 *
 * $Id: misc.c,v 1.68 1999/10/20 22:08:08 cort Exp $
 * 
 * Adapted for PowerPC by Gary Thomas
 *
 * Rewritten by Cort Dougan ([e-mail])
 * One day to be replaced by a single bootloader for chrp/prep/pmac. -- Cort
 */

#include <linux/types.h>
#include "../coffboot/zlib.h"
#include "asm/residual.h"
#include <linux/elf.h>
#include <linux/config.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/bootinfo.h>
#include <asm/mmu.h>
#if defined(CONFIG_SERIAL_CONSOLE)
#include "ns16550.h"
struct NS16550 *com_port;
#endif /* CONFIG_SERIAL_CONSOLE */

/*
 * Please send me load/board info and such data for hardware not
 * listed here so I can keep track since things are getting tricky
 * with the different load addrs with different firmware.  This will
 * help to avoid breaking the load/boot process.
 * -- Cort
 */
char *avail_ram;
char *end_avail;
extern char _end[];

#ifdef CONFIG_CMDLINE
#define CMDLINE CONFIG_CMDLINE
#else
#define CMDLINE "";
#endif
char cmd_preset[] = CMDLINE;
char cmd_buf[256];
char *cmd_line = cmd_buf;

int keyb_present = 1;	/* keyboard controller is present by default */
RESIDUAL hold_resid_buf;
RESIDUAL *hold_residual = &hold_resid_buf;
unsigned long initrd_start = 0, initrd_end = 0;
char *zimage_start;
int zimage_size;

char *vidmem = (char *)0xC00B8000;
int lines, cols;
int orig_x, orig_y;

void puts(const char *);
void putc(const char c);
void puthex(unsigned long val);
void _bcopy(char *src, char *dst, int len);
void * memcpy(void * __dest, __const void * __src,
			    int __n);
void gunzip(void *, int, unsigned char *, int *);
static int _cvt(unsigned long val, char *buf, long radix, char *digits);
unsigned char inb(int);

void pause()
{
	puts("pause\n");
}

void exit()
{
	puts("exit\n");
	while(1); 
}

static void clear_screen()
{
	int i, j;
	for (i = 0;  i < lines;  i++) {
	  for (j = 0;  j < cols;  j++) {
	    vidmem[((i*cols)+j)*2] = ' ';
	    vidmem[((i*cols)+j)*2+1] = 0x07;
	  }
	}
}

static void scroll()
{
	int i;

	memcpy ( vidmem, vidmem + cols * 2, ( lines - 1 ) * cols * 2 );
	for ( i = ( lines - 1 ) * cols * 2; i < lines * cols * 2; i += 2 )
		vidmem[i] = ' ';
}

tstc(void)
{
#if defined(CONFIG_SERIAL_CONSOLE)
	if (keyb_present)
		return (CRT_tstc() || NS16550_tstc(com_port));
	else
		NS16550_tstc(com_port);
#else
	return (CRT_tstc() );
#endif /* CONFIG_SERIAL_CONSOLE */
}

getc(void)
{
	while (1) {
#if defined(CONFIG_SERIAL_CONSOLE)
		if (NS16550_tstc(com_port)) return (NS16550_getc(com_port));
#endif /* CONFIG_SERIAL_CONSOLE */
		if (keyb_present)
			if (CRT_tstc()) return (CRT_getc());
	}
}

void 
putc(const char c)
{
	int x,y;

#if defined(CONFIG_SERIAL_CONSOLE)
	NS16550_putc(com_port, c);
	if ( c == '\n' ) NS16550_putc(com_port, '\r');
#endif /* CONFIG_SERIAL_CONSOLE */

	x = orig_x;
	y = orig_y;

	if ( c == '\n' ) {
		x = 0;
		if ( ++y >= lines ) {
			scroll();
			y--;
		}
	} else if (c == '\r') {
		x = 0;
	} else if (c == '\b') {
		if (x > 0) {
			x--;
		}
	} else {
		vidmem [ ( x + cols * y ) * 2 ] = c; 
		if ( ++x >= cols ) {
			x = 0;
			if ( ++y >= lines ) {
				scroll();
				y--;
			}
		}
	}

	cursor(x, y);

	orig_x = x;
	orig_y = y;
}

void puts(const char *s)
{
	int x,y;
	char c;

	x = orig_x;
	y = orig_y;

	while ( ( c = *s++ ) != '\0' ) {
#if defined(CONFIG_SERIAL_CONSOLE)
	        NS16550_putc(com_port, c);
	        if ( c == '\n' ) NS16550_putc(com_port, '\r');
#endif /* CONFIG_SERIAL_CONSOLE */

		if ( c == '\n' ) {
			x = 0;
			if ( ++y >= lines ) {
				scroll();
				y--;
			}
		} else if (c == '\b') {
		  if (x > 0) {
		    x--;
		  }
		} else {
			vidmem [ ( x + cols * y ) * 2 ] = c; 
			if ( ++x >= cols ) {
				x = 0;
				if ( ++y >= lines ) {
					scroll();
					y--;
				}
			}
		}
	}

	cursor(x, y);

	orig_x = x;
	orig_y = y;
}

void * memcpy(void * __dest, __const void * __src,
			    int __n)
{
	int i;
	char *d = (char *)__dest, *s = (char *)__src;

	for (i=0;i<__n;i++) d[i] = s[i];
}

int memcmp(__const void * __dest, __const void * __src,
			    int __n)
{
	int i;
	char *d = (char *)__dest, *s = (char *)__src;

	for (i=0;i<__n;i++, d++, s++)
	{
		if (*d != *s)
		{
			return (*s - *d);
		}
	}
	return (0);
}

void error(char *x)
{
	puts("\n\n");
	puts(x);
	puts("\n\n -- System halted");

	while(1);	/* Halt */
}

void *zalloc(void *x, unsigned items, unsigned size)
{
	void *p = avail_ram;
	
	size *= items;
	size = (size + 7) & -8;
	avail_ram += size;
	if (avail_ram > end_avail) {
		puts("oops... out of memory\n");
		pause();
	}
	return p;
}

void zfree(void *x, void *addr, unsigned nb)
{
}

#define HEAD_CRC	2
#define EXTRA_FIELD	4
#define ORIG_NAME	8
#define COMMENT		0x10
#define RESERVED	0xe0

#define DEFLATED	8


void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
{
	z_stream s;
	int r, i, flags;
	
	/* skip header */
	i = 10;
	flags = src[3];
	if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
		puts("bad gzipped data\n");
		exit();
	}
	if ((flags & EXTRA_FIELD) != 0)
		i = 12 + src[10] + (src[11] << 8);
	if ((flags & ORIG_NAME) != 0)
		while (src[i++] != 0)
			;
	if ((flags & COMMENT) != 0)
		while (src[i++] != 0)
			;
	if ((flags & HEAD_CRC) != 0)
		i += 2;
	if (i >= *lenp) {
		puts("gunzip: ran out of data in header\n");
		exit();
	}
	
	s.zalloc = zalloc;
	s.zfree = zfree;
	r = inflateInit2(&s, -MAX_WBITS);
	if (r != Z_OK) {
		puts("inflateInit2 returned %d\n");
		exit();
	}
	s.next_in = src + i;
	s.avail_in = *lenp - i;
	s.next_out = dst;
	s.avail_out = dstlen;
	r = inflate(&s, Z_FINISH);
	if (r != Z_OK && r != Z_STREAM_END) {
		puts("inflate returned %d\n");
		exit();
	}
	*lenp = s.next_out - (unsigned char *) dst;
	inflateEnd(&s);
}

unsigned long
decompress_kernel(unsigned long load_addr, int num_words, unsigned long cksum,
		  RESIDUAL *residual, void *OFW_interface)
{
	int timer;
	extern unsigned long start;
	char *cp, ch;
	unsigned long i;
	BATU *u;
	BATL *l;
	unsigned long TotalMemory;
	unsigned long orig_MSR;
	int dev_handle;
	int mem_info[2];
	int res, size;
	unsigned char board_type;
	unsigned char base_mod;

	lines = 25;
	cols = 80;
	orig_x = 0;
	orig_y = 24;
	
	/*
	 * IBM's have the MMU on, so we have to disable it or
	 * things get really unhappy in the kernel when
	 * trying to setup the BATs with the MMU on
	 * -- Cort
	 */
	flush_instruction_cache();
	_put_HID0(_get_HID0() & ~0x0000C000);
	_put_MSR((orig_MSR = _get_MSR()) & ~0x0030);

#if defined(CONFIG_SERIAL_CONSOLE)
	com_port = (struct NS16550 *)NS16550_init(0);
#endif /* CONFIG_SERIAL_CONSOLE */
	vga_init(0xC0000000);

	if (residual)
	{
		/* Is this Motorola PPCBug? */
		if ((1 & residual->VitalProductData.FirmwareSupports) &&
		    (1 == residual->VitalProductData.FirmwareSupplier)) {
			board_type = inb(0x800) & 0xF0;

			/* If this is genesis 2 board then check for no
			 * keyboard controller and more than one processor.
			 */
			if (board_type == 0xe0) {	
				base_mod = inb(0x803);
				/* if a MVME2300/2400 or a Sitka then no keyboard */
				if((base_mod == 0xFA) || (base_mod == 0xF9) ||
				   (base_mod == 0xE1)) {
					keyb_present = 0;	/* no keyboard */
				}
			}
		}
		memcpy(hold_residual,residual,sizeof(RESIDUAL));
	} else {
		/* Assume 32M in the absence of more info... */
		TotalMemory = 0x02000000;
		/*
		 * This is a 'best guess' check.  We want to make sure
		 * we don't try this on a PReP box without OF
		 *     -- Cort
		 */
		while (OFW_interface && ((unsigned long)OFW_interface < 0x10000000) )
		{
			/* The MMU needs to be on when we call OFW */
			_put_MSR(orig_MSR);
			of_init(OFW_interface);

			/* get handle to memory description */
			res = of_finddevice("/memory@0", 
					    &dev_handle);
			// puthex(res);  puts("\n");
			if (res) break;
			
			/* get the info */
			// puts("get info = ");
			res = of_getprop(dev_handle, 
					 "reg", 
					 mem_info, 
					 sizeof(mem_info), 
					 &size);
			// puthex(res);  puts(", info = "); puthex(mem_info[0]);  
			// puts(" ");  puthex(mem_info[1]);   puts("\n");
			if (res) break;
			
			TotalMemory = mem_info[1];
			break;
		}
		hold_residual->TotalMemory = TotalMemory;
		residual = hold_residual;
		/* Turn MMU back off */
		_put_MSR(orig_MSR & ~0x0030);
        }

	/* assume the chunk below 8M is free */
	end_avail = (char *)0x00800000;

	/* tell the user where we were loaded at and where we
	 * were relocated to for debugging this process
	 */
	puts("loaded at:     "); puthex(load_addr);
	puts(" "); puthex((unsigned long)(load_addr + (4*num_words))); puts("\n");
	if ( (unsigned long)load_addr != (unsigned long)&start )
	{
		puts("relocated to:  "); puthex((unsigned long)&start);
		puts(" ");
		puthex((unsigned long)((unsigned long)&start + (4*num_words)));