arch/sparc/kernel/prom_common.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* prom_common.c: OF device tree support common code.
   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  *  Adapted for sparc by David S. Miller davem@davemloft.net
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/export.h>
  15 #include <linux/errno.h>
  16 #include <linux/mutex.h>
  17 #include <linux/slab.h>
  18 #include <linux/of.h>
  19 #include <linux/of_pdt.h>
  20 #include <asm/prom.h>
  21 #include <asm/oplib.h>
  22
  23 #include "prom.h"
  24
  25 struct device_node *of_console_device;
  26 EXPORT_SYMBOL(of_console_device);
  27
  28 char *of_console_path;
  29 EXPORT_SYMBOL(of_console_path);
  30
  31 char *of_console_options;
  32 EXPORT_SYMBOL(of_console_options);
  33
  34 int of_getintprop_default(struct device_node *np, const char *name, int def)
  35 {
  36         struct property *prop;
  37         int len;
  38
  39         prop = of_find_property(np, name, &len);
  40         if (!prop || len != 4)
  41                 return def;
  42
  43         return *(int *) prop->value;
  44 }
  45 EXPORT_SYMBOL(of_getintprop_default);
  46
  47 DEFINE_MUTEX(of_set_property_mutex);
  48 EXPORT_SYMBOL(of_set_property_mutex);
  49
  50 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
  51 {
  52         struct property **prevp;
  53         unsigned long flags;
  54         void *new_val;
  55         int err;
  56
  57         new_val = kmemdup(val, len, GFP_KERNEL);
  58         if (!new_val)
  59                 return -ENOMEM;
  60
  61         err = -ENODEV;
  62
  63         mutex_lock(&of_set_property_mutex);
  64         raw_spin_lock_irqsave(&devtree_lock, flags);
  65         prevp = &dp->properties;
  66         while (*prevp) {
  67                 struct property *prop = *prevp;
  68
  69                 if (!strcasecmp(prop->name, name)) {
  70                         void *old_val = prop->value;
  71                         int ret;
  72
  73                         ret = prom_setprop(dp->phandle, name, val, len);
  74
  75                         err = -EINVAL;
  76                         if (ret >= 0) {
  77                                 prop->value = new_val;
  78                                 prop->length = len;
  79
  80                                 if (OF_IS_DYNAMIC(prop))
  81                                         kfree(old_val);
  82
  83                                 OF_MARK_DYNAMIC(prop);
  84
  85                                 err = 0;
  86                         }
  87                         break;
  88                 }
  89                 prevp = &(*prevp)->next;
  90         }
  91         raw_spin_unlock_irqrestore(&devtree_lock, flags);
  92         mutex_unlock(&of_set_property_mutex);
  93
  94         /* XXX Upate procfs if necessary... */
  95
  96         return err;
  97 }
  98 EXPORT_SYMBOL(of_set_property);
  99
 100 int of_find_in_proplist(const char *list, const char *match, int len)
 101 {
 102         while (len > 0) {
 103                 int l;
 104
 105                 if (!strcmp(list, match))
 106                         return 1;
 107                 l = strlen(list) + 1;
 108                 list += l;
 109                 len -= l;
 110         }
 111         return 0;
 112 }
 113 EXPORT_SYMBOL(of_find_in_proplist);
 114
 115 /*
 116  * SPARC32 and SPARC64's prom_nextprop() do things differently
 117  * here, despite sharing the same interface.  SPARC32 doesn't fill in 'buf',
 118  * returning NULL on an error.  SPARC64 fills in 'buf', but sets it to an
 119  * empty string upon error.
 120  */
 121 static int __init handle_nextprop_quirks(char *buf, const char *name)
 122 {
 123         if (!name || strlen(name) == 0)
 124                 return -1;
 125
 126 #ifdef CONFIG_SPARC32
 127         strcpy(buf, name);
 128 #endif
 129         return 0;
 130 }
 131
 132 static int __init prom_common_nextprop(phandle node, char *prev, char *buf)
 133 {
 134         const char *name;
 135
 136         buf[0] = '\0';
 137         name = prom_nextprop(node, prev, buf);
 138         return handle_nextprop_quirks(buf, name);
 139 }
 140
 141 unsigned int prom_early_allocated __initdata;
 142
 143 static struct of_pdt_ops prom_sparc_ops __initdata = {
 144         .nextprop = prom_common_nextprop,
 145         .getproplen = prom_getproplen,
 146         .getproperty = prom_getproperty,
 147         .getchild = prom_getchild,
 148         .getsibling = prom_getsibling,
 149 };
 150
 151 void __init prom_build_devicetree(void)
 152 {
 153         of_pdt_build_devicetree(prom_root_node, &prom_sparc_ops);
 154         of_console_init();
 155
 156         pr_info("PROM: Built device tree with %u bytes of memory.\n",
 157                         prom_early_allocated);
 158 }