#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>

#include <subarch.h>
#include "sniprom.h"

#define MAX_ARG	64

static char	*iargv[MAX_ARG];
static int	iargc=0;
static char	*label=NULL;

extern unsigned long _end;

void prom_wait(const char *prompt) {
	printf("%s: called\n\r", __FUNCTION__);
}

void prom_fatal(const char *message, ...) {
	va_list ap;

	if (message != NULL) {
		printf("FATAL ERROR:  ");
		va_start(ap, message);
		vprintf(message, ap);
		va_end(ap);
	}

	prom_wait("\n\r--- Press <spacebar> to enter ARC interactive mode ---");
	__prom_reset();
}

int (*__prom_lseek)(FILE, int, int)   = NULL;


/*
 * The SNI Prom does not contain an official entry point for "prom_seek" which is
 * a pain and basically is a showstopper for bootloaders. There is a seek function
 * though which seems to be inbetween prom_open and prom_read. We try to find
 * it by looking for the function prolog e.g. the $sp setup. We then know the
 * address of the seek.		flo@rfc822.org 2007-08-13
 */

void prom_init(void ) {
	unsigned int	jump;
	unsigned int	*readaddr,
			*openaddr,
			*saddr;

	jump = *((unsigned int *)PROM_ENTRY(PROM_READ));
	readaddr=(unsigned int *) (((jump & 0x03ffffff)<<2)|0xb0000000);
	jump = *((unsigned int *)PROM_ENTRY(PROM_OPEN));
	openaddr= (unsigned int *) (((jump & 0x03ffffff)<<2)|0xb0000000);

	for(saddr=readaddr-1;saddr>openaddr;saddr--) {
		/* Search for addiu $sp, negative */
		if ((*saddr & 0xffff8000) == 0x27bd8000) {
			__prom_lseek=(void *) saddr;
			break;
		}
	}

	if (__prom_lseek == NULL)
		prom_fatal("Didnt find prom_seek prolog between open and read\n\r");
}


/* Give 1MByte of memory behind the arcboot to the allocator */
void prom_init_malloc(unsigned long loadaddr, unsigned long size) {
	malloc_area_add((unsigned long) &_end, 0x100000);
}

int prom_seek(FILE stream, long long position, int whence) {
	int	pos32=position, res;

	res=__prom_lseek(stream, pos32, whence);

	if (res != position)
		prom_fatal("Seek failed\n\r");

	return 0;
}

void prom_restart(void ) {
	printf("%s: called\n\r", __FUNCTION__);
}

void prom_flush_cache_all(void ) {
	__prom_flushcache();
}

void prom_return_interactive(void ) {
	printf("%s: called\n\r", __FUNCTION__);
}

int prom_write(FILE stream, char *buf, unsigned long len, unsigned long *rlen) {
	int	res;
	/* SNI returns no status but standard conform length */
	res=__prom_write(stream, buf, len);
	*rlen=res;
	return res<0;
}

/*
 * We have seen larger reads to fail on RM200C Prom Version 5
 * and RM400 Prom Version 4. It seems this is secondary cache related. As we
 * would like to use the read-ahead and cache we simply split the reads into
 * smaller chunks here.
 *
 */
int prom_read(FILE stream, char *buf, unsigned long len, unsigned long *rlen) {
	int	res=0,i;
	int	read=0, thisread;

	while(read < len) {
		int left=len-read;
		if (left > 4096)
			thisread=4096;
		else
			thisread=left;

		res=__prom_read(stream, buf+read, thisread);

		read+=thisread;

		if (res < thisread)
			break;
	}
	*rlen=read;

	return (len > read);
}

int prom_open(char *name, int mode, FILE *stream) {
	int	res;
	res=__prom_open(name, mode);
	*stream=res;
	return 0;
}

int prom_close(FILE stream) {
	return 0;
}

void prom_add_arg(char *arg) {
	iargv[iargc++]=strdup(arg);
}

/*
 * dkncr(0,0,10) label cmd line arg
 * Kernel drops argv[0] so we need to add dkncr... and drop the label
 *
 */
int prom_parse_args(int argc, char **argv) {
	int	i;
	prom_add_arg(argv[0]);
	if (argc > 1)
		label=strdup(argv[1]);
	for(i=2;i<argc;i++ )
		prom_add_arg(argv[i]);
	return iargc;
}

char *prom_get_label(void ) {
	return (label) ? label : "linux";
}

char *prom_get_partition(void ) {
	return "dkncr(0,0,1)";
}

char *prom_get_options(void ) {
	return NULL;
}

void prom_get_karg(int *argc, char ***argv) {
	*argc=iargc;
	*argv=iargv;
}