1 /* 2 * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) 3 * 4 * Based on reduced version of METAG 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 12 #include <linux/init.h> 13 #include <linux/reboot.h> 14 #include <linux/memblock.h> 15 #include <linux/of.h> 16 #include <linux/of_fdt.h> 17 #include <asm/prom.h> 18 #include <asm/clk.h> 19 #include <asm/mach_desc.h> 20 21 /* called from unflatten_device_tree() to bootstrap devicetree itself */ 22 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) 23 { 24 return __va(memblock_alloc(size, align)); 25 } 26 27 /** 28 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel 29 * @dt: virtual address pointer to dt blob 30 * 31 * If a dtb was passed to the kernel, then use it to choose the correct 32 * machine_desc and to setup the system. 33 */ 34 struct machine_desc * __init setup_machine_fdt(void *dt) 35 { 36 struct boot_param_header *devtree = dt; 37 struct machine_desc *mdesc = NULL, *mdesc_best = NULL; 38 unsigned int score, mdesc_score = ~1; 39 unsigned long dt_root; 40 const char *model, *compat; 41 void *clk; 42 char manufacturer[16]; 43 unsigned long len; 44 45 /* check device tree validity */ 46 if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) 47 return NULL; 48 49 initial_boot_params = devtree; 50 dt_root = of_get_flat_dt_root(); 51 52 /* 53 * The kernel could be multi-platform enabled, thus could have many 54 * "baked-in" machine descriptors. Search thru all for the best 55 * "compatible" string match. 56 */ 57 for_each_machine_desc(mdesc) { 58 score = of_flat_dt_match(dt_root, mdesc->dt_compat); 59 if (score > 0 && score < mdesc_score) { 60 mdesc_best = mdesc; 61 mdesc_score = score; 62 } 63 } 64 if (!mdesc_best) { 65 const char *prop; 66 long size; 67 68 pr_err("\n unrecognized device tree list:\n[ "); 69 70 prop = of_get_flat_dt_prop(dt_root, "compatible", &size); 71 if (prop) { 72 while (size > 0) { 73 printk("'%s' ", prop); 74 size -= strlen(prop) + 1; 75 prop += strlen(prop) + 1; 76 } 77 } 78 printk("]\n\n"); 79 80 machine_halt(); 81 } 82 83 /* compat = "<manufacturer>,<model>" */ 84 compat = mdesc_best->dt_compat[0]; 85 86 model = strchr(compat, ','); 87 if (model) 88 model++; 89 90 strlcpy(manufacturer, compat, model ? model - compat : strlen(compat)); 91 92 pr_info("Board \"%s\" from %s (Manufacturer)\n", model, manufacturer); 93 94 /* Retrieve various information from the /chosen node */ 95 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); 96 97 /* Initialize {size,address}-cells info */ 98 of_scan_flat_dt(early_init_dt_scan_root, NULL); 99 100 /* Setup memory, calling early_init_dt_add_memory_arch */ 101 of_scan_flat_dt(early_init_dt_scan_memory, NULL); 102 103 clk = of_get_flat_dt_prop(dt_root, "clock-frequency", &len); 104 if (clk) 105 arc_set_core_freq(of_read_ulong(clk, len/4)); 106 107 return mdesc_best; 108 } 109 110 /* 111 * Copy the flattened DT out of .init since unflattening doesn't copy strings 112 * and the normal DT APIs refs them from orig flat DT 113 */ 114 void __init copy_devtree(void) 115 { 116 void *alloc = early_init_dt_alloc_memory_arch( 117 be32_to_cpu(initial_boot_params->totalsize), 64); 118 if (alloc) { 119 memcpy(alloc, initial_boot_params, 120 be32_to_cpu(initial_boot_params->totalsize)); 121 initial_boot_params = alloc; 122 } 123 } 124