projects/linux·blob assoc-array-fixes · refs

314 lines · 8.6 KiB

1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kernel.h>
3#include <linux/of.h>
4#include <linux/of_device.h>
5#include <linux/of_address.h>
6#include <linux/of_iommu.h>
7#include <linux/of_reserved_mem.h>
8#include <linux/dma-direct.h> /* for bus_dma_region */
9#include <linux/dma-map-ops.h>
10#include <linux/init.h>
11#include <linux/slab.h>
12#include <linux/platform_device.h>
13
14#include <asm/errno.h>
15#include "of_private.h"
16
17/**
18 * of_match_device - Tell if a struct device matches an of_device_id list
19 * @matches: array of of_device_id match structures to search in
20 * @dev: the OF device structure to match against
21 *
22 * Used by a driver to check whether an platform_device present in the
23 * system is in its list of supported devices.
24 */
25const struct of_device_id *of_match_device(const struct of_device_id *matches,
26 const struct device *dev)
27{
28 if (!matches || !dev->of_node || dev_of_node_reused(dev))
29 return NULL;
30 return of_match_node(matches, dev->of_node);
31}
32EXPORT_SYMBOL(of_match_device);
33
34static void
35of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
36{
37 struct device_node *of_node = dev->of_node;
38 struct of_phandle_iterator it;
39 int rc, i = 0;
40
41 if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL))
42 return;
43
44 /*
45 * If dev->of_node doesn't exist or doesn't contain memory-region, try
46 * the OF node having DMA configuration.
47 */
48 if (!of_property_present(of_node, "memory-region"))
49 of_node = np;
50
51 of_for_each_phandle(&it, rc, of_node, "memory-region", NULL, 0) {
52 /*
53 * There might be multiple memory regions, but only one
54 * restricted-dma-pool region is allowed.
55 */
56 if (of_device_is_compatible(it.node, "restricted-dma-pool") &&
57 of_device_is_available(it.node)) {
58 if (of_reserved_mem_device_init_by_idx(dev, of_node, i))
59 dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");
60 of_node_put(it.node);
61 break;
62 }
63 i++;
64 }
65
66}
67
68/**
69 * of_dma_configure_id - Setup DMA configuration
70 * @dev: Device to apply DMA configuration
71 * @np: Pointer to OF node having DMA configuration
72 * @force_dma: Whether device is to be set up by of_dma_configure() even if
73 * DMA capability is not explicitly described by firmware.
74 * @id: Optional const pointer value input id
75 *
76 * Try to get devices's DMA configuration from DT and update it
77 * accordingly.
78 *
79 * If platform code needs to use its own special DMA configuration, it
80 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
81 * to fix up DMA configuration.
82 */
83int of_dma_configure_id(struct device *dev, struct device_node *np,
84 bool force_dma, const u32 *id)
85{
86 const struct bus_dma_region *map = NULL;
87 struct device_node *bus_np;
88 u64 mask, end = 0;
89 bool coherent, set_map = false;
90 int ret;
91
92 if (dev->dma_range_map) {
93 dev_dbg(dev, "dma_range_map already set\n");
94 goto skip_map;
95 }
96
97 if (np == dev->of_node)
98 bus_np = __of_get_dma_parent(np);
99 else
100 bus_np = of_node_get(np);
101
102 ret = of_dma_get_range(bus_np, &map);
103 of_node_put(bus_np);
104 if (ret < 0) {
105 /*
106 * For legacy reasons, we have to assume some devices need
107 * DMA configuration regardless of whether "dma-ranges" is
108 * correctly specified or not.
109 */
110 if (!force_dma)
111 return ret == -ENODEV ? 0 : ret;
112 } else {
113 /* Determine the overall bounds of all DMA regions */
114 end = dma_range_map_max(map);
115 set_map = true;
116 }
117skip_map:
118 /*
119 * If @dev is expected to be DMA-capable then the bus code that created
120 * it should have initialised its dma_mask pointer by this point. For
121 * now, we'll continue the legacy behaviour of coercing it to the
122 * coherent mask if not, but we'll no longer do so quietly.
123 */
124 if (!dev->dma_mask) {
125 dev_warn(dev, "DMA mask not set\n");
126 dev->dma_mask = &dev->coherent_dma_mask;
127 }
128
129 if (!end && dev->coherent_dma_mask)
130 end = dev->coherent_dma_mask;
131 else if (!end)
132 end = (1ULL << 32) - 1;
133
134 /*
135 * Limit coherent and dma mask based on size and default mask
136 * set by the driver.
137 */
138 mask = DMA_BIT_MASK(ilog2(end) + 1);
139 dev->coherent_dma_mask &= mask;
140 *dev->dma_mask &= mask;
141 /* ...but only set bus limit and range map if we found valid dma-ranges earlier */
142 if (set_map) {
143 dev->bus_dma_limit = end;
144 dev->dma_range_map = map;
145 }
146
147 coherent = of_dma_is_coherent(np);
148 dev_dbg(dev, "device is%sdma coherent\n",
149 coherent ? " " : " not ");
150
151 ret = of_iommu_configure(dev, np, id);
152 if (ret == -EPROBE_DEFER) {
153 /* Don't touch range map if it wasn't set from a valid dma-ranges */
154 if (set_map)
155 dev->dma_range_map = NULL;
156 kfree(map);
157 return -EPROBE_DEFER;
158 }
159 /* Take all other IOMMU errors to mean we'll just carry on without it */
160 dev_dbg(dev, "device is%sbehind an iommu\n",
161 !ret ? " " : " not ");
162
163 arch_setup_dma_ops(dev, coherent);
164
165 if (ret)
166 of_dma_set_restricted_buffer(dev, np);
167
168 return 0;
169}
170EXPORT_SYMBOL_GPL(of_dma_configure_id);
171
172const void *of_device_get_match_data(const struct device *dev)
173{
174 const struct of_device_id *match;
175
176 match = of_match_device(dev->driver->of_match_table, dev);
177 if (!match)
178 return NULL;
179
180 return match->data;
181}
182EXPORT_SYMBOL(of_device_get_match_data);
183
184/**
185 * of_device_modalias - Fill buffer with newline terminated modalias string
186 * @dev: Calling device
187 * @str: Modalias string
188 * @len: Size of @str
189 */
190ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
191{
192 ssize_t sl;
193
194 if (!dev || !dev->of_node || dev_of_node_reused(dev))
195 return -ENODEV;
196
197 sl = of_modalias(dev->of_node, str, len - 2);
198 if (sl < 0)
199 return sl;
200 if (sl > len - 2)
201 return -ENOMEM;
202
203 str[sl++] = '\n';
204 str[sl] = 0;
205 return sl;
206}
207EXPORT_SYMBOL_GPL(of_device_modalias);
208
209/**
210 * of_device_uevent - Display OF related uevent information
211 * @dev: Device to display the uevent information for
212 * @env: Kernel object's userspace event reference to fill up
213 */
214void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
215{
216 const char *compat, *type;
217 struct alias_prop *app;
218 struct property *p;
219 int seen = 0;
220
221 if ((!dev) || (!dev->of_node))
222 return;
223
224 add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);
225 add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);
226 type = of_node_get_device_type(dev->of_node);
227 if (type)
228 add_uevent_var(env, "OF_TYPE=%s", type);
229
230 /* Since the compatible field can contain pretty much anything
231 * it's not really legal to split it out with commas. We split it
232 * up using a number of environment variables instead. */
233 of_property_for_each_string(dev->of_node, "compatible", p, compat) {
234 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
235 seen++;
236 }
237 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
238
239 seen = 0;
240 mutex_lock(&of_mutex);
241 list_for_each_entry(app, &aliases_lookup, link) {
242 if (dev->of_node == app->np) {
243 add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
244 app->alias);
245 seen++;
246 }
247 }
248 mutex_unlock(&of_mutex);
249}
250EXPORT_SYMBOL_GPL(of_device_uevent);
251
252int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
253{
254 int sl;
255
256 if ((!dev) || (!dev->of_node) || dev_of_node_reused(dev))
257 return -ENODEV;
258
259 /* Devicetree modalias is tricky, we add it in 2 steps */
260 if (add_uevent_var(env, "MODALIAS="))
261 return -ENOMEM;
262
263 sl = of_modalias(dev->of_node, &env->buf[env->buflen-1],
264 sizeof(env->buf) - env->buflen);
265 if (sl < 0)
266 return sl;
267 if (sl >= (sizeof(env->buf) - env->buflen))
268 return -ENOMEM;
269 env->buflen += sl;
270
271 return 0;
272}
273EXPORT_SYMBOL_GPL(of_device_uevent_modalias);
274
275/**
276 * of_device_make_bus_id - Use the device node data to assign a unique name
277 * @dev: pointer to device structure that is linked to a device tree node
278 *
279 * This routine will first try using the translated bus address to
280 * derive a unique name. If it cannot, then it will prepend names from
281 * parent nodes until a unique name can be derived.
282 */
283void of_device_make_bus_id(struct device *dev)
284{
285 struct device_node *node = dev->of_node;
286 const __be32 *reg;
287 u64 addr;
288 u32 mask;
289
290 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
291 while (node->parent) {
292 /*
293 * If the address can be translated, then that is as much
294 * uniqueness as we need. Make it the first component and return
295 */
296 reg = of_get_property(node, "reg", NULL);
297 if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
298 if (!of_property_read_u32(node, "mask", &mask))
299 dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn",
300 addr, ffs(mask) - 1, node, dev_name(dev));
301
302 else
303 dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
304 addr, node, dev_name(dev));
305 return;
306 }
307
308 /* format arguments only used if dev_name() resolves to NULL */
309 dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
310 kbasename(node->full_name), dev_name(dev));
311 node = node->parent;
312 }
313}
314EXPORT_SYMBOL_GPL(of_device_make_bus_id);