xref: /openbmc/linux/arch/nios2/kernel/prom.c (revision ecc23d0a422a3118fcf6e4f0a46e17a6c2047b02)
11ccea77eSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
295acd4c7SLey Foon Tan /*
395acd4c7SLey Foon Tan  * Device tree support
495acd4c7SLey Foon Tan  *
5e8bf5bc7SLey Foon Tan  * Copyright (C) 2013, 2015 Altera Corporation
695acd4c7SLey Foon Tan  * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
795acd4c7SLey Foon Tan  *
895acd4c7SLey Foon Tan  * Based on MIPS support for CONFIG_OF device tree support
995acd4c7SLey Foon Tan  *
1095acd4c7SLey Foon Tan  * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
1195acd4c7SLey Foon Tan  */
1295acd4c7SLey Foon Tan 
1395acd4c7SLey Foon Tan #include <linux/init.h>
1495acd4c7SLey Foon Tan #include <linux/types.h>
1557c8a661SMike Rapoport #include <linux/memblock.h>
1695acd4c7SLey Foon Tan #include <linux/of.h>
1795acd4c7SLey Foon Tan #include <linux/of_fdt.h>
1895acd4c7SLey Foon Tan #include <linux/io.h>
1995acd4c7SLey Foon Tan 
2095acd4c7SLey Foon Tan #include <asm/sections.h>
2195acd4c7SLey Foon Tan 
early_init_devtree(void * params)2295acd4c7SLey Foon Tan void __init early_init_devtree(void *params)
2395acd4c7SLey Foon Tan {
2495acd4c7SLey Foon Tan 	__be32 *dtb = (u32 *)__dtb_start;
2595acd4c7SLey Foon Tan #if defined(CONFIG_NIOS2_DTB_AT_PHYS_ADDR)
2695acd4c7SLey Foon Tan 	if (be32_to_cpup((__be32 *)CONFIG_NIOS2_DTB_PHYS_ADDR) ==
2795acd4c7SLey Foon Tan 		 OF_DT_HEADER) {
2895acd4c7SLey Foon Tan 		params = (void *)CONFIG_NIOS2_DTB_PHYS_ADDR;
29*1103d3b5SUsama Arif 		early_init_dt_scan(params, __pa(params));
3095acd4c7SLey Foon Tan 		return;
3195acd4c7SLey Foon Tan 	}
3295acd4c7SLey Foon Tan #endif
3395acd4c7SLey Foon Tan 	if (be32_to_cpu((__be32) *dtb) == OF_DT_HEADER)
3495acd4c7SLey Foon Tan 		params = (void *)__dtb_start;
3595acd4c7SLey Foon Tan 
36*1103d3b5SUsama Arif 	early_init_dt_scan(params, __pa(params));
3795acd4c7SLey Foon Tan }
38