Loading...
1/*
2 * Copyright 2010 Benjamin Herrenschmidt, IBM Corp
3 * <benh@kernel.crashing.org>
4 * and David Gibson, IBM Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
14 * the GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/kernel.h>
22#include <linux/slab.h>
23#include <linux/export.h>
24#include <asm/debugfs.h>
25#include <asm/prom.h>
26#include <asm/scom.h>
27#include <linux/uaccess.h>
28
29const struct scom_controller *scom_controller;
30EXPORT_SYMBOL_GPL(scom_controller);
31
32struct device_node *scom_find_parent(struct device_node *node)
33{
34 struct device_node *par, *tmp;
35 const u32 *p;
36
37 for (par = of_node_get(node); par;) {
38 if (of_get_property(par, "scom-controller", NULL))
39 break;
40 p = of_get_property(par, "scom-parent", NULL);
41 tmp = par;
42 if (p == NULL)
43 par = of_get_parent(par);
44 else
45 par = of_find_node_by_phandle(*p);
46 of_node_put(tmp);
47 }
48 return par;
49}
50EXPORT_SYMBOL_GPL(scom_find_parent);
51
52scom_map_t scom_map_device(struct device_node *dev, int index)
53{
54 struct device_node *parent;
55 unsigned int cells, size;
56 const __be32 *prop, *sprop;
57 u64 reg, cnt;
58 scom_map_t ret;
59
60 parent = scom_find_parent(dev);
61
62 if (parent == NULL)
63 return 0;
64
65 /*
66 * We support "scom-reg" properties for adding scom registers
67 * to a random device-tree node with an explicit scom-parent
68 *
69 * We also support the simple "reg" property if the device is
70 * a direct child of a scom controller.
71 *
72 * In case both exist, "scom-reg" takes precedence.
73 */
74 prop = of_get_property(dev, "scom-reg", &size);
75 sprop = of_get_property(parent, "#scom-cells", NULL);
76 if (!prop && parent == dev->parent) {
77 prop = of_get_property(dev, "reg", &size);
78 sprop = of_get_property(parent, "#address-cells", NULL);
79 }
80 if (!prop)
81 return NULL;
82 cells = sprop ? be32_to_cpup(sprop) : 1;
83 size >>= 2;
84
85 if (index >= (size / (2*cells)))
86 return 0;
87
88 reg = of_read_number(&prop[index * cells * 2], cells);
89 cnt = of_read_number(&prop[index * cells * 2 + cells], cells);
90
91 ret = scom_map(parent, reg, cnt);
92 of_node_put(parent);
93
94 return ret;
95}
96EXPORT_SYMBOL_GPL(scom_map_device);
97
98#ifdef CONFIG_SCOM_DEBUGFS
99struct scom_debug_entry {
100 struct device_node *dn;
101 struct debugfs_blob_wrapper path;
102 char name[16];
103};
104
105static ssize_t scom_debug_read(struct file *filp, char __user *ubuf,
106 size_t count, loff_t *ppos)
107{
108 struct scom_debug_entry *ent = filp->private_data;
109 u64 __user *ubuf64 = (u64 __user *)ubuf;
110 loff_t off = *ppos;
111 ssize_t done = 0;
112 u64 reg, reg_cnt, val;
113 scom_map_t map;
114 int rc;
115
116 if (off < 0 || (off & 7) || (count & 7))
117 return -EINVAL;
118 reg = off >> 3;
119 reg_cnt = count >> 3;
120
121 map = scom_map(ent->dn, reg, reg_cnt);
122 if (!scom_map_ok(map))
123 return -ENXIO;
124
125 for (reg = 0; reg < reg_cnt; reg++) {
126 rc = scom_read(map, reg, &val);
127 if (!rc)
128 rc = put_user(val, ubuf64);
129 if (rc) {
130 if (!done)
131 done = rc;
132 break;
133 }
134 ubuf64++;
135 *ppos += 8;
136 done += 8;
137 }
138 scom_unmap(map);
139 return done;
140}
141
142static ssize_t scom_debug_write(struct file* filp, const char __user *ubuf,
143 size_t count, loff_t *ppos)
144{
145 struct scom_debug_entry *ent = filp->private_data;
146 u64 __user *ubuf64 = (u64 __user *)ubuf;
147 loff_t off = *ppos;
148 ssize_t done = 0;
149 u64 reg, reg_cnt, val;
150 scom_map_t map;
151 int rc;
152
153 if (off < 0 || (off & 7) || (count & 7))
154 return -EINVAL;
155 reg = off >> 3;
156 reg_cnt = count >> 3;
157
158 map = scom_map(ent->dn, reg, reg_cnt);
159 if (!scom_map_ok(map))
160 return -ENXIO;
161
162 for (reg = 0; reg < reg_cnt; reg++) {
163 rc = get_user(val, ubuf64);
164 if (!rc)
165 rc = scom_write(map, reg, val);
166 if (rc) {
167 if (!done)
168 done = rc;
169 break;
170 }
171 ubuf64++;
172 done += 8;
173 }
174 scom_unmap(map);
175 return done;
176}
177
178static const struct file_operations scom_debug_fops = {
179 .read = scom_debug_read,
180 .write = scom_debug_write,
181 .open = simple_open,
182 .llseek = default_llseek,
183};
184
185static int scom_debug_init_one(struct dentry *root, struct device_node *dn,
186 int i)
187{
188 struct scom_debug_entry *ent;
189 struct dentry *dir;
190
191 ent = kzalloc(sizeof(*ent), GFP_KERNEL);
192 if (!ent)
193 return -ENOMEM;
194
195 ent->dn = of_node_get(dn);
196 snprintf(ent->name, 16, "%08x", i);
197 ent->path.data = (void*)kasprintf(GFP_KERNEL, "%pOF", dn);
198 ent->path.size = strlen((char *)ent->path.data);
199
200 dir = debugfs_create_dir(ent->name, root);
201 if (!dir) {
202 of_node_put(dn);
203 kfree(ent->path.data);
204 kfree(ent);
205 return -1;
206 }
207
208 debugfs_create_blob("devspec", 0400, dir, &ent->path);
209 debugfs_create_file("access", 0600, dir, ent, &scom_debug_fops);
210
211 return 0;
212}
213
214static int scom_debug_init(void)
215{
216 struct device_node *dn;
217 struct dentry *root;
218 int i, rc;
219
220 root = debugfs_create_dir("scom", powerpc_debugfs_root);
221 if (!root)
222 return -1;
223
224 i = rc = 0;
225 for_each_node_with_property(dn, "scom-controller") {
226 int id = of_get_ibm_chip_id(dn);
227 if (id == -1)
228 id = i;
229 rc |= scom_debug_init_one(root, dn, id);
230 i++;
231 }
232
233 return rc;
234}
235device_initcall(scom_debug_init);
236#endif /* CONFIG_SCOM_DEBUGFS */
1/*
2 * Copyright 2010 Benjamin Herrenschmidt, IBM Corp
3 * <benh@kernel.crashing.org>
4 * and David Gibson, IBM Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
14 * the GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/kernel.h>
22#include <linux/debugfs.h>
23#include <linux/slab.h>
24#include <asm/prom.h>
25#include <asm/scom.h>
26
27const struct scom_controller *scom_controller;
28EXPORT_SYMBOL_GPL(scom_controller);
29
30struct device_node *scom_find_parent(struct device_node *node)
31{
32 struct device_node *par, *tmp;
33 const u32 *p;
34
35 for (par = of_node_get(node); par;) {
36 if (of_get_property(par, "scom-controller", NULL))
37 break;
38 p = of_get_property(par, "scom-parent", NULL);
39 tmp = par;
40 if (p == NULL)
41 par = of_get_parent(par);
42 else
43 par = of_find_node_by_phandle(*p);
44 of_node_put(tmp);
45 }
46 return par;
47}
48EXPORT_SYMBOL_GPL(scom_find_parent);
49
50scom_map_t scom_map_device(struct device_node *dev, int index)
51{
52 struct device_node *parent;
53 unsigned int cells, size;
54 const u32 *prop;
55 u64 reg, cnt;
56 scom_map_t ret;
57
58 parent = scom_find_parent(dev);
59
60 if (parent == NULL)
61 return 0;
62
63 prop = of_get_property(parent, "#scom-cells", NULL);
64 cells = prop ? *prop : 1;
65
66 prop = of_get_property(dev, "scom-reg", &size);
67 if (!prop)
68 return 0;
69 size >>= 2;
70
71 if (index >= (size / (2*cells)))
72 return 0;
73
74 reg = of_read_number(&prop[index * cells * 2], cells);
75 cnt = of_read_number(&prop[index * cells * 2 + cells], cells);
76
77 ret = scom_map(parent, reg, cnt);
78 of_node_put(parent);
79
80 return ret;
81}
82EXPORT_SYMBOL_GPL(scom_map_device);
83
84#ifdef CONFIG_SCOM_DEBUGFS
85struct scom_debug_entry {
86 struct device_node *dn;
87 unsigned long addr;
88 scom_map_t map;
89 spinlock_t lock;
90 char name[8];
91 struct debugfs_blob_wrapper blob;
92};
93
94static int scom_addr_set(void *data, u64 val)
95{
96 struct scom_debug_entry *ent = data;
97
98 ent->addr = 0;
99 scom_unmap(ent->map);
100
101 ent->map = scom_map(ent->dn, val, 1);
102 if (scom_map_ok(ent->map))
103 ent->addr = val;
104 else
105 return -EFAULT;
106
107 return 0;
108}
109
110static int scom_addr_get(void *data, u64 *val)
111{
112 struct scom_debug_entry *ent = data;
113 *val = ent->addr;
114 return 0;
115}
116DEFINE_SIMPLE_ATTRIBUTE(scom_addr_fops, scom_addr_get, scom_addr_set,
117 "0x%llx\n");
118
119static int scom_val_set(void *data, u64 val)
120{
121 struct scom_debug_entry *ent = data;
122
123 if (!scom_map_ok(ent->map))
124 return -EFAULT;
125
126 scom_write(ent->map, 0, val);
127
128 return 0;
129}
130
131static int scom_val_get(void *data, u64 *val)
132{
133 struct scom_debug_entry *ent = data;
134
135 if (!scom_map_ok(ent->map))
136 return -EFAULT;
137
138 *val = scom_read(ent->map, 0);
139 return 0;
140}
141DEFINE_SIMPLE_ATTRIBUTE(scom_val_fops, scom_val_get, scom_val_set,
142 "0x%llx\n");
143
144static int scom_debug_init_one(struct dentry *root, struct device_node *dn,
145 int i)
146{
147 struct scom_debug_entry *ent;
148 struct dentry *dir;
149
150 ent = kzalloc(sizeof(*ent), GFP_KERNEL);
151 if (!ent)
152 return -ENOMEM;
153
154 ent->dn = of_node_get(dn);
155 ent->map = SCOM_MAP_INVALID;
156 spin_lock_init(&ent->lock);
157 snprintf(ent->name, 8, "scom%d", i);
158 ent->blob.data = dn->full_name;
159 ent->blob.size = strlen(dn->full_name);
160
161 dir = debugfs_create_dir(ent->name, root);
162 if (!dir) {
163 of_node_put(dn);
164 kfree(ent);
165 return -1;
166 }
167
168 debugfs_create_file("addr", 0600, dir, ent, &scom_addr_fops);
169 debugfs_create_file("value", 0600, dir, ent, &scom_val_fops);
170 debugfs_create_blob("path", 0400, dir, &ent->blob);
171
172 return 0;
173}
174
175static int scom_debug_init(void)
176{
177 struct device_node *dn;
178 struct dentry *root;
179 int i, rc;
180
181 root = debugfs_create_dir("scom", powerpc_debugfs_root);
182 if (!root)
183 return -1;
184
185 i = rc = 0;
186 for_each_node_with_property(dn, "scom-controller")
187 rc |= scom_debug_init_one(root, dn, i++);
188
189 return rc;
190}
191device_initcall(scom_debug_init);
192#endif /* CONFIG_SCOM_DEBUGFS */