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/mmu.h>
 40#include <asm/pgtable.h>
 41#include <asm/sections.h>
 42#include <asm/pci-bridge.h>
 43
 44void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 45{
 46	memblock_add(base, size);
 47}
 48
 49void * __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
 55char *stdout;
 56
 57int __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 */
104int __init of_early_console(void *version)
105{
106	return of_scan_flat_dt(early_init_dt_scan_chosen_serial, version);
107}
108#endif
109
110void __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
139void __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)
160static struct debugfs_blob_wrapper flat_dt_blob;
161
162static 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}
176device_initcall(export_flat_device_tree);
177#endif