staging/easycap: don't cast NULL pointer
[wandboard.git] / arch / sparc / kernel / prom_32.c
blob05fb253305831095c660bb3aab077ac837f8f16e
1 /*
2 * Procedures for creating, accessing and interpreting the device tree.
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
10 * Adapted for sparc32 by David S. Miller davem@davemloft.net
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
18 #include <linux/kernel.h>
19 #include <linux/types.h>
20 #include <linux/string.h>
21 #include <linux/mm.h>
22 #include <linux/bootmem.h>
23 #include <linux/module.h>
25 #include <asm/prom.h>
26 #include <asm/oplib.h>
27 #include <asm/leon.h>
28 #include <asm/leon_amba.h>
30 #include "prom.h"
32 void * __init prom_early_alloc(unsigned long size)
34 void *ret;
36 ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
37 if (ret != NULL)
38 memset(ret, 0, size);
40 prom_early_allocated += size;
42 return ret;
45 /* The following routines deal with the black magic of fully naming a
46 * node.
48 * Certain well known named nodes are just the simple name string.
50 * Actual devices have an address specifier appended to the base name
51 * string, like this "foo@addr". The "addr" can be in any number of
52 * formats, and the platform plus the type of the node determine the
53 * format and how it is constructed.
55 * For children of the ROOT node, the naming convention is fixed and
56 * determined by whether this is a sun4u or sun4v system.
58 * For children of other nodes, it is bus type specific. So
59 * we walk up the tree until we discover a "device_type" property
60 * we recognize and we go from there.
62 static void __init sparc32_path_component(struct device_node *dp, char *tmp_buf)
64 struct linux_prom_registers *regs;
65 struct property *rprop;
67 rprop = of_find_property(dp, "reg", NULL);
68 if (!rprop)
69 return;
71 regs = rprop->value;
72 sprintf(tmp_buf, "%s@%x,%x",
73 dp->name,
74 regs->which_io, regs->phys_addr);
77 /* "name@slot,offset" */
78 static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
80 struct linux_prom_registers *regs;
81 struct property *prop;
83 prop = of_find_property(dp, "reg", NULL);
84 if (!prop)
85 return;
87 regs = prop->value;
88 sprintf(tmp_buf, "%s@%x,%x",
89 dp->name,
90 regs->which_io,
91 regs->phys_addr);
94 /* "name@devnum[,func]" */
95 static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
97 struct linux_prom_pci_registers *regs;
98 struct property *prop;
99 unsigned int devfn;
101 prop = of_find_property(dp, "reg", NULL);
102 if (!prop)
103 return;
105 regs = prop->value;
106 devfn = (regs->phys_hi >> 8) & 0xff;
107 if (devfn & 0x07) {
108 sprintf(tmp_buf, "%s@%x,%x",
109 dp->name,
110 devfn >> 3,
111 devfn & 0x07);
112 } else {
113 sprintf(tmp_buf, "%s@%x",
114 dp->name,
115 devfn >> 3);
119 /* "name@addrhi,addrlo" */
120 static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
122 struct linux_prom_registers *regs;
123 struct property *prop;
125 prop = of_find_property(dp, "reg", NULL);
126 if (!prop)
127 return;
129 regs = prop->value;
131 sprintf(tmp_buf, "%s@%x,%x",
132 dp->name,
133 regs->which_io, regs->phys_addr);
136 /* "name:vendor:device@irq,addrlo" */
137 static void __init ambapp_path_component(struct device_node *dp, char *tmp_buf)
139 struct amba_prom_registers *regs;
140 unsigned int *intr, *device, *vendor, reg0;
141 struct property *prop;
142 int interrupt = 0;
144 /* In order to get a unique ID in the device tree (multiple AMBA devices
145 * may have the same name) the node number is printed
147 prop = of_find_property(dp, "reg", NULL);
148 if (!prop) {
149 reg0 = (unsigned int)dp->phandle;
150 } else {
151 regs = prop->value;
152 reg0 = regs->phys_addr;
155 /* Not all cores have Interrupt */
156 prop = of_find_property(dp, "interrupts", NULL);
157 if (!prop)
158 intr = &interrupt; /* IRQ0 does not exist */
159 else
160 intr = prop->value;
162 prop = of_find_property(dp, "vendor", NULL);
163 if (!prop)
164 return;
165 vendor = prop->value;
166 prop = of_find_property(dp, "device", NULL);
167 if (!prop)
168 return;
169 device = prop->value;
171 sprintf(tmp_buf, "%s:%d:%d@%x,%x",
172 dp->name, *vendor, *device,
173 *intr, reg0);
176 static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
178 struct device_node *parent = dp->parent;
180 if (parent != NULL) {
181 if (!strcmp(parent->type, "pci") ||
182 !strcmp(parent->type, "pciex"))
183 return pci_path_component(dp, tmp_buf);
184 if (!strcmp(parent->type, "sbus"))
185 return sbus_path_component(dp, tmp_buf);
186 if (!strcmp(parent->type, "ebus"))
187 return ebus_path_component(dp, tmp_buf);
188 if (!strcmp(parent->type, "ambapp"))
189 return ambapp_path_component(dp, tmp_buf);
191 /* "isa" is handled with platform naming */
194 /* Use platform naming convention. */
195 return sparc32_path_component(dp, tmp_buf);
198 char * __init build_path_component(struct device_node *dp)
200 char tmp_buf[64], *n;
202 tmp_buf[0] = '\0';
203 __build_path_component(dp, tmp_buf);
204 if (tmp_buf[0] == '\0')
205 strcpy(tmp_buf, dp->name);
207 n = prom_early_alloc(strlen(tmp_buf) + 1);
208 strcpy(n, tmp_buf);
210 return n;
213 extern void restore_current(void);
215 void __init of_console_init(void)
217 char *msg = "OF stdout device is: %s\n";
218 struct device_node *dp;
219 unsigned long flags;
220 const char *type;
221 phandle node;
222 int skip, tmp, fd;
224 of_console_path = prom_early_alloc(256);
226 switch (prom_vers) {
227 case PROM_V0:
228 skip = 0;
229 switch (*romvec->pv_stdout) {
230 case PROMDEV_SCREEN:
231 type = "display";
232 break;
234 case PROMDEV_TTYB:
235 skip = 1;
236 /* FALLTHRU */
238 case PROMDEV_TTYA:
239 type = "serial";
240 break;
242 default:
243 prom_printf("Invalid PROM_V0 stdout value %u\n",
244 *romvec->pv_stdout);
245 prom_halt();
248 tmp = skip;
249 for_each_node_by_type(dp, type) {
250 if (!tmp--)
251 break;
253 if (!dp) {
254 prom_printf("Cannot find PROM_V0 console node.\n");
255 prom_halt();
257 of_console_device = dp;
259 strcpy(of_console_path, dp->full_name);
260 if (!strcmp(type, "serial")) {
261 strcat(of_console_path,
262 (skip ? ":b" : ":a"));
264 break;
266 default:
267 case PROM_V2:
268 case PROM_V3:
269 fd = *romvec->pv_v2bootargs.fd_stdout;
271 spin_lock_irqsave(&prom_lock, flags);
272 node = (*romvec->pv_v2devops.v2_inst2pkg)(fd);
273 restore_current();
274 spin_unlock_irqrestore(&prom_lock, flags);
276 if (!node) {
277 prom_printf("Cannot resolve stdout node from "
278 "instance %08x.\n", fd);
279 prom_halt();
281 dp = of_find_node_by_phandle(node);
282 type = of_get_property(dp, "device_type", NULL);
284 if (!type) {
285 prom_printf("Console stdout lacks "
286 "device_type property.\n");
287 prom_halt();
290 if (strcmp(type, "display") && strcmp(type, "serial")) {
291 prom_printf("Console device_type is neither display "
292 "nor serial.\n");
293 prom_halt();
296 of_console_device = dp;
298 if (prom_vers == PROM_V2) {
299 strcpy(of_console_path, dp->full_name);
300 switch (*romvec->pv_stdout) {
301 case PROMDEV_TTYA:
302 strcat(of_console_path, ":a");
303 break;
304 case PROMDEV_TTYB:
305 strcat(of_console_path, ":b");
306 break;
308 } else {
309 const char *path;
311 dp = of_find_node_by_path("/");
312 path = of_get_property(dp, "stdout-path", NULL);
313 if (!path) {
314 prom_printf("No stdout-path in root node.\n");
315 prom_halt();
317 strcpy(of_console_path, path);
319 break;
322 of_console_options = strrchr(of_console_path, ':');
323 if (of_console_options) {
324 of_console_options++;
325 if (*of_console_options == '\0')
326 of_console_options = NULL;
329 prom_printf(msg, of_console_path);
330 printk(msg, of_console_path);
333 void __init of_fill_in_cpu_data(void)
337 void __init irq_trans_init(struct device_node *dp)