1 /* 2 * Device tree support 3 * 4 * Copyright (C) 2013, 2015 Altera Corporation 5 * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw> 6 * 7 * Based on MIPS support for CONFIG_OF device tree support 8 * 9 * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program. If not, see <http://www.gnu.org/licenses/>. 23 * 24 */ 25 26 #include <linux/init.h> 27 #include <linux/types.h> 28 #include <linux/bootmem.h> 29 #include <linux/of.h> 30 #include <linux/of_fdt.h> 31 #include <linux/io.h> 32 33 #include <asm/sections.h> 34 35 void __init early_init_dt_add_memory_arch(u64 base, u64 size) 36 { 37 u64 kernel_start = (u64)virt_to_phys(_text); 38 39 if (!memory_size && 40 (kernel_start >= base) && (kernel_start < (base + size))) 41 memory_size = size; 42 43 } 44 45 int __init early_init_dt_reserve_memory_arch(phys_addr_t base, phys_addr_t size, 46 bool nomap) 47 { 48 reserve_bootmem(base, size, BOOTMEM_DEFAULT); 49 return 0; 50 } 51 52 void __init early_init_devtree(void *params) 53 { 54 __be32 *dtb = (u32 *)__dtb_start; 55 #if defined(CONFIG_NIOS2_DTB_AT_PHYS_ADDR) 56 if (be32_to_cpup((__be32 *)CONFIG_NIOS2_DTB_PHYS_ADDR) == 57 OF_DT_HEADER) { 58 params = (void *)CONFIG_NIOS2_DTB_PHYS_ADDR; 59 early_init_dt_scan(params); 60 return; 61 } 62 #endif 63 if (be32_to_cpu((__be32) *dtb) == OF_DT_HEADER) 64 params = (void *)__dtb_start; 65 66 early_init_dt_scan(params); 67 } 68