init.c

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/* $Id: init.c,v 1.14 2000/01/29 01:09:12 anton Exp $
 * init.c:  Initialize internal variables used by the PROM
 *          library functions.
 *
 * Copyright (C) 1995 David S. Miller ([e-mail])
 * Copyright (C) 1998 Jakub Jelinek ([e-mail])
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>

#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/sun4prom.h>

struct linux_romvec *romvec;
enum prom_major_version prom_vers;
unsigned int prom_rev, prom_prev;
linux_sun4_romvec *sun4_romvec;

/* The root node of the prom device tree. */
int prom_root_node;

int prom_stdin, prom_stdout;

/* Pointer to the device tree operations structure. */
struct linux_nodeops *prom_nodeops;

/* You must call prom_init() before you attempt to use any of the
 * routines in the prom library.  It returns 0 on success, 1 on
 * failure.  It gets passed the pointer to the PROM vector.
 */

extern void prom_meminit(void);
extern void prom_ranges_init(void);

void __init prom_init(struct linux_romvec *rp)
{
#ifdef CONFIG_SUN4
	extern struct linux_romvec *sun4_prom_init(void);
	rp = sun4_prom_init();
#endif
	romvec = rp;

	switch(romvec->pv_romvers) {
	case 0:
		prom_vers = PROM_V0;
		break;
	case 2:
		prom_vers = PROM_V2;
		break;
	case 3:
		prom_vers = PROM_V3;
		break;
	case 40:
		prom_vers = PROM_SUN4;
		break;
	default:
		prom_printf("PROMLIB: Bad PROM version %d\n",
			    romvec->pv_romvers);
		prom_halt();
		break;
	};

	prom_rev = romvec->pv_plugin_revision;
	prom_prev = romvec->pv_printrev;
	prom_nodeops = romvec->pv_nodeops;

	prom_root_node = prom_getsibling(0);
	if((prom_root_node == 0) || (prom_root_node == -1))
		prom_halt();

	if((((unsigned long) prom_nodeops) == 0) || 
	   (((unsigned long) prom_nodeops) == -1))
		prom_halt();

	if(prom_vers == PROM_V2 || prom_vers == PROM_V3) {
		prom_stdout = *romvec->pv_v2bootargs.fd_stdout;
		prom_stdin  = *romvec->pv_v2bootargs.fd_stdin;
	}
	
	prom_meminit();

	prom_ranges_init();

#ifndef CONFIG_SUN4
	/* SUN4 prints this in sun4_prom_init */
	printk("PROMLIB: Sun Boot Prom Version %d Revision %d\n",
	       romvec->pv_romvers, prom_rev);
#endif

	/* Initialization successful. */
	return;
}