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