1 /* 2 * Procedures for creating, accessing and interpreting the device tree. 3 * 4 * Paul Mackerras August 1996. 5 * Copyright (C) 1996-2005 Paul Mackerras. 6 * 7 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. 8 * {engebret|bergner}@us.ibm.com 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 */ 15 16 #include <stdarg.h> 17 #include <linux/kernel.h> 18 #include <linux/string.h> 19 #include <linux/init.h> 20 #include <linux/threads.h> 21 #include <linux/spinlock.h> 22 #include <linux/types.h> 23 #include <linux/pci.h> 24 #include <linux/stringify.h> 25 #include <linux/delay.h> 26 #include <linux/initrd.h> 27 #include <linux/bitops.h> 28 #include <linux/module.h> 29 #include <linux/kexec.h> 30 #include <linux/debugfs.h> 31 #include <linux/irq.h> 32 #include <linux/memblock.h> 33 34 #include <asm/prom.h> 35 #include <asm/page.h> 36 #include <asm/processor.h> 37 #include <asm/irq.h> 38 #include <linux/io.h> 39 #include <asm/system.h> 40 #include <asm/mmu.h> 41 #include <asm/pgtable.h> 42 #include <asm/sections.h> 43 #include <asm/pci-bridge.h> 44 45 void __init early_init_dt_add_memory_arch(u64 base, u64 size) 46 { 47 memblock_add(base, size); 48 } 49 50 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) 51 { 52 return __va(memblock_alloc(size, align)); 53 } 54 55 #ifdef CONFIG_EARLY_PRINTK 56 char *stdout; 57 58 int __init early_init_dt_scan_chosen_serial(unsigned long node, 59 const char *uname, int depth, void *data) 60 { 61 unsigned long l; 62 char *p; 63 64 pr_debug("%s: depth: %d, uname: %s\n", __func__, depth, uname); 65 66 if (depth == 1 && (strcmp(uname, "chosen") == 0 || 67 strcmp(uname, "chosen@0") == 0)) { 68 p = of_get_flat_dt_prop(node, "linux,stdout-path", &l); 69 if (p != NULL && l > 0) 70 stdout = p; /* store pointer to stdout-path */ 71 } 72 73 if (stdout && strstr(stdout, uname)) { 74 p = of_get_flat_dt_prop(node, "compatible", &l); 75 pr_debug("Compatible string: %s\n", p); 76 77 if ((strncmp(p, "xlnx,xps-uart16550", 18) == 0) || 78 (strncmp(p, "xlnx,axi-uart16550", 18) == 0)) { 79 unsigned int addr; 80 81 *(u32 *)data = UART16550; 82 83 addr = *(u32 *)of_get_flat_dt_prop(node, "reg", &l); 84 addr += *(u32 *)of_get_flat_dt_prop(node, 85 "reg-offset", &l); 86 /* clear register offset */ 87 return be32_to_cpu(addr) & ~3; 88 } 89 if ((strncmp(p, "xlnx,xps-uartlite", 17) == 0) || 90 (strncmp(p, "xlnx,opb-uartlite", 17) == 0) || 91 (strncmp(p, "xlnx,axi-uartlite", 17) == 0) || 92 (strncmp(p, "xlnx,mdm", 8) == 0)) { 93 unsigned int *addrp; 94 95 *(u32 *)data = UARTLITE; 96 97 addrp = of_get_flat_dt_prop(node, "reg", &l); 98 return be32_to_cpup(addrp); /* return address */ 99 } 100 } 101 return 0; 102 } 103 104 /* this function is looking for early console - Microblaze specific */ 105 int __init of_early_console(void *version) 106 { 107 return of_scan_flat_dt(early_init_dt_scan_chosen_serial, version); 108 } 109 #endif 110 111 void __init early_init_devtree(void *params) 112 { 113 pr_debug(" -> early_init_devtree(%p)\n", params); 114 115 /* Setup flat device-tree pointer */ 116 initial_boot_params = params; 117 118 /* Retrieve various informations from the /chosen node of the 119 * device-tree, including the platform type, initrd location and 120 * size, TCE reserve, and more ... 121 */ 122 of_scan_flat_dt(early_init_dt_scan_chosen, cmd_line); 123 124 /* Scan memory nodes and rebuild MEMBLOCKs */ 125 memblock_init(); 126 of_scan_flat_dt(early_init_dt_scan_root, NULL); 127 of_scan_flat_dt(early_init_dt_scan_memory, NULL); 128 129 /* Save command line for /proc/cmdline and then parse parameters */ 130 strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE); 131 parse_early_param(); 132 133 memblock_analyze(); 134 135 pr_debug("Phys. mem: %lx\n", (unsigned long) memblock_phys_mem_size()); 136 137 pr_debug(" <- early_init_devtree()\n"); 138 } 139 140 #ifdef CONFIG_BLK_DEV_INITRD 141 void __init early_init_dt_setup_initrd_arch(unsigned long start, 142 unsigned long end) 143 { 144 initrd_start = (unsigned long)__va(start); 145 initrd_end = (unsigned long)__va(end); 146 initrd_below_start_ok = 1; 147 } 148 #endif 149 150 /******* 151 * 152 * New implementation of the OF "find" APIs, return a refcounted 153 * object, call of_node_put() when done. The device tree and list 154 * are protected by a rw_lock. 155 * 156 * Note that property management will need some locking as well, 157 * this isn't dealt with yet. 158 * 159 *******/ 160 161 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG) 162 static struct debugfs_blob_wrapper flat_dt_blob; 163 164 static int __init export_flat_device_tree(void) 165 { 166 struct dentry *d; 167 168 flat_dt_blob.data = initial_boot_params; 169 flat_dt_blob.size = initial_boot_params->totalsize; 170 171 d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR, 172 of_debugfs_root, &flat_dt_blob); 173 if (!d) 174 return 1; 175 176 return 0; 177 } 178 device_initcall(export_flat_device_tree); 179 #endif 180