xref: /kernel/linux/linux-6.6/arch/powerpc/boot/epapr.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Bootwrapper for ePAPR compliant firmwares
 *
 * Copyright 2010 David Gibson <david@gibson.dropbear.id.au>, IBM Corporation.
 *
 * Based on earlier bootwrappers by:
 * (c) Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp,\
 *   and
 * Scott Wood <scottwood@freescale.com>
 * Copyright (c) 2007 Freescale Semiconductor, Inc.
 */

#include "ops.h"
#include "stdio.h"
#include "io.h"
#include <libfdt.h>

BSS_STACK(4096);

#define EPAPR_SMAGIC	0x65504150
#define EPAPR_EMAGIC	0x45504150

static unsigned epapr_magic;
static unsigned long ima_size;
static unsigned long fdt_addr;

static void platform_fixups(void)
{
	if ((epapr_magic != EPAPR_EMAGIC)
	    && (epapr_magic != EPAPR_SMAGIC))
		fatal("r6 contained 0x%08x instead of ePAPR magic number\n",
		      epapr_magic);

	if (ima_size < (unsigned long)_end)
		printf("WARNING: Image loaded outside IMA!"
		       " (_end=%p, ima_size=0x%lx)\n", _end, ima_size);
	if (ima_size < fdt_addr)
		printf("WARNING: Device tree address is outside IMA!"
		       "(fdt_addr=0x%lx, ima_size=0x%lx)\n", fdt_addr,
		       ima_size);
	if (ima_size < fdt_addr + fdt_totalsize((void *)fdt_addr))
		printf("WARNING: Device tree extends outside IMA!"
		       " (fdt_addr=0x%lx, size=0x%x, ima_size=0x%lx\n",
		       fdt_addr, fdt_totalsize((void *)fdt_addr), ima_size);
}

void epapr_platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
			 unsigned long r6, unsigned long r7)
{
	epapr_magic = r6;
	ima_size = r7;
	fdt_addr = r3;

	/* FIXME: we should process reserve entries */

	simple_alloc_init(_end, ima_size - (unsigned long)_end, 32, 64);

	fdt_init((void *)fdt_addr);

	serial_console_init();
	platform_ops.fixups = platform_fixups;
}