1 /* SPDX-License-Identifier: GPL-2.0-only */
2
3 #include <assert.h>
4 #include <console/console.h>
5 #include <device/device.h>
6 #include <device/pci_def.h>
7 #include <device/pci_type.h>
8 #include <fw_config.h>
9 #include <types.h>
10
11 /** Linked list of ALL devices */
12 DEVTREE_CONST struct device *DEVTREE_CONST all_devices = &dev_root;
13
14 /**
15 * Given a PCI bus and a devfn number, find the device structure.
16 *
17 * Note that this function can return the incorrect device prior
18 * to PCI enumeration because the secondary field of the bus object
19 * is 0. The failing scenario is determined by the order of the
20 * devices in all_devices singly-linked list as well as the time
21 * when this function is called (secondary reflecting topology).
22 *
23 * @param bus The bus number.
24 * @param devfn A device/function number.
25 * @return Pointer to the device structure (if found), 0 otherwise.
26 */
27
dev_find_slot(unsigned int bus,unsigned int devfn)28 static DEVTREE_CONST struct device *dev_find_slot(unsigned int bus,
29 unsigned int devfn)
30 {
31 DEVTREE_CONST struct device *dev, *result;
32
33 result = 0;
34 for (dev = all_devices; dev; dev = dev->next) {
35 if ((dev->path.type == DEVICE_PATH_PCI) &&
36 (dev->upstream->secondary == bus) &&
37 (dev->upstream->segment_group == 0) &&
38 (dev->path.pci.devfn == devfn)) {
39 result = dev;
40 break;
41 }
42 }
43 return result;
44 }
45
46 /**
47 * Given a Device Path Type, find the device structure.
48 *
49 * @param prev_match The previously matched device instance.
50 * @param path_type The Device Path Type.
51 * @return Pointer to the device structure (if found), 0 otherwise.
52 */
dev_find_path(DEVTREE_CONST struct device * prev_match,enum device_path_type path_type)53 DEVTREE_CONST struct device *dev_find_path(
54 DEVTREE_CONST struct device *prev_match,
55 enum device_path_type path_type)
56 {
57 DEVTREE_CONST struct device *dev, *result = NULL;
58
59 if (prev_match == NULL)
60 prev_match = all_devices;
61 else
62 prev_match = prev_match->next;
63
64 for (dev = prev_match; dev; dev = dev->next) {
65 if (dev->path.type == path_type) {
66 result = dev;
67 break;
68 }
69 }
70 return result;
71 }
72
73 /**
74 * Given a device pointer, find the next PCI device.
75 *
76 * @param previous_dev A pointer to a PCI device structure.
77 * @return Pointer to the next device structure (if found), 0 otherwise.
78 */
dev_find_next_pci_device(DEVTREE_CONST struct device * previous_dev)79 DEVTREE_CONST struct device *dev_find_next_pci_device(
80 DEVTREE_CONST struct device *previous_dev)
81 {
82 return dev_find_path(previous_dev, DEVICE_PATH_PCI);
83 }
84
path_eq(const struct device_path * path1,const struct device_path * path2)85 static int path_eq(const struct device_path *path1,
86 const struct device_path *path2)
87 {
88 int equal = 0;
89
90 if (!path1 || !path2) {
91 assert(path1);
92 assert(path2);
93 /* Return 0 in case assert is considered non-fatal. */
94 return 0;
95 }
96
97 if (path1->type != path2->type)
98 return 0;
99
100 switch (path1->type) {
101 case DEVICE_PATH_NONE:
102 break;
103 case DEVICE_PATH_ROOT:
104 equal = 1;
105 break;
106 case DEVICE_PATH_PCI:
107 equal = (path1->pci.devfn == path2->pci.devfn);
108 break;
109 case DEVICE_PATH_PNP:
110 equal = (path1->pnp.port == path2->pnp.port) &&
111 (path1->pnp.device == path2->pnp.device);
112 break;
113 case DEVICE_PATH_I2C:
114 equal = (path1->i2c.device == path2->i2c.device) &&
115 (path1->i2c.mode_10bit == path2->i2c.mode_10bit);
116 break;
117 case DEVICE_PATH_APIC:
118 equal = (path1->apic.apic_id == path2->apic.apic_id);
119 break;
120 case DEVICE_PATH_DOMAIN:
121 equal = (path1->domain.domain == path2->domain.domain);
122 break;
123 case DEVICE_PATH_CPU_CLUSTER:
124 equal = (path1->cpu_cluster.cluster
125 == path2->cpu_cluster.cluster);
126 break;
127 case DEVICE_PATH_CPU:
128 equal = (path1->cpu.id == path2->cpu.id);
129 break;
130 case DEVICE_PATH_CPU_BUS:
131 equal = (path1->cpu_bus.id == path2->cpu_bus.id);
132 break;
133 case DEVICE_PATH_GENERIC:
134 equal = (path1->generic.id == path2->generic.id) &&
135 (path1->generic.subid == path2->generic.subid);
136 break;
137 case DEVICE_PATH_SPI:
138 equal = (path1->spi.cs == path2->spi.cs);
139 break;
140 case DEVICE_PATH_USB:
141 equal = (path1->usb.port_type == path2->usb.port_type) &&
142 (path1->usb.port_id == path2->usb.port_id);
143 break;
144 case DEVICE_PATH_MMIO:
145 equal = (path1->mmio.addr == path2->mmio.addr);
146 break;
147 case DEVICE_PATH_GPIO:
148 equal = (path1->gpio.id == path2->gpio.id);
149 break;
150 case DEVICE_PATH_MDIO:
151 equal = (path1->mdio.addr == path2->mdio.addr);
152 break;
153
154 default:
155 printk(BIOS_ERR, "Unknown device type: %d\n", path1->type);
156 break;
157 }
158
159 return equal;
160 }
161
162 /**
163 * See if a device structure exists for path.
164 *
165 * @param parent The bus to find the device on.
166 * @param path The relative path from the bus to the appropriate device.
167 * @return Pointer to a device structure for the device on bus at path
168 * or 0/NULL if no device is found.
169 */
find_dev_path(const struct bus * parent,const struct device_path * path)170 DEVTREE_CONST struct device *find_dev_path(
171 const struct bus *parent, const struct device_path *path)
172 {
173 DEVTREE_CONST struct device *child;
174
175 if (!parent) {
176 BUG();
177 /* Return NULL in case asserts are considered non-fatal. */
178 return NULL;
179 }
180
181 for (child = parent->children; child; child = child->sibling) {
182 if (path_eq(path, &child->path))
183 break;
184 }
185 return child;
186 }
187
188 /**
189 * Find the device structure given an array of nested device paths,
190 *
191 * @param parent The parent bus to start the search on.
192 * @param nested_path An array of relative paths from the parent bus to the target device.
193 * @param nested_path_length Number of path elements in nested_path array.
194 * @return Pointer to a device structure for the device at nested path
195 * or 0/NULL if no device is found.
196 */
find_dev_nested_path(const struct bus * parent,const struct device_path nested_path[],size_t nested_path_length)197 DEVTREE_CONST struct device *find_dev_nested_path(
198 const struct bus *parent, const struct device_path nested_path[],
199 size_t nested_path_length)
200 {
201 DEVTREE_CONST struct device *child;
202
203 if (!parent || !nested_path || !nested_path_length)
204 return NULL;
205
206 child = find_dev_path(parent, nested_path);
207
208 /* Terminate recursion at end of nested path or child not found */
209 if (nested_path_length == 1 || !child)
210 return child;
211
212 return find_dev_nested_path(child->downstream, nested_path + 1, nested_path_length - 1);
213 }
214
pcidev_path_behind(const struct bus * parent,pci_devfn_t devfn)215 DEVTREE_CONST struct device *pcidev_path_behind(
216 const struct bus *parent, pci_devfn_t devfn)
217 {
218 const struct device_path path = {
219 .type = DEVICE_PATH_PCI,
220 .pci.devfn = devfn,
221 };
222 return find_dev_path(parent, &path);
223 }
224
pcidev_path_on_bus(unsigned int bus,pci_devfn_t devfn)225 DEVTREE_CONST struct device *pcidev_path_on_bus(unsigned int bus, pci_devfn_t devfn)
226 {
227 DEVTREE_CONST struct bus *parent = pci_root_bus();
228 DEVTREE_CONST struct device *dev = parent->children;
229
230 /* FIXME: Write the loop with topology links. */
231 while (dev) {
232 if (dev->path.type != DEVICE_PATH_PCI) {
233 dev = dev->next;
234 continue;
235 }
236 if (dev->upstream->secondary == bus && dev->upstream->segment_group == 0)
237 return pcidev_path_behind(dev->upstream, devfn);
238 dev = dev->next;
239 }
240 return NULL;
241 }
242
pci_root_bus(void)243 DEVTREE_CONST struct bus *pci_root_bus(void)
244 {
245 DEVTREE_CONST struct device *pci_domain;
246 static DEVTREE_CONST struct bus *pci_root;
247
248 if (pci_root)
249 return pci_root;
250
251 pci_domain = dev_find_path(NULL, DEVICE_PATH_DOMAIN);
252 if (!pci_domain)
253 return NULL;
254
255 pci_root = pci_domain->downstream;
256 return pci_root;
257 }
258
pcidev_path_on_root(pci_devfn_t devfn)259 DEVTREE_CONST struct device *pcidev_path_on_root(pci_devfn_t devfn)
260 {
261 return pcidev_path_behind(pci_root_bus(), devfn);
262 }
263
pcidev_on_root(uint8_t dev,uint8_t fn)264 DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn)
265 {
266 return pcidev_path_on_root(PCI_DEVFN(dev, fn));
267 }
268
pcidev_path_behind_pci2pci_bridge(const struct device * bridge,pci_devfn_t devfn)269 DEVTREE_CONST struct device *pcidev_path_behind_pci2pci_bridge(
270 const struct device *bridge,
271 pci_devfn_t devfn)
272 {
273 if (!bridge || (bridge->path.type != DEVICE_PATH_PCI)) {
274 BUG();
275 /* Return NULL in case asserts are non-fatal. */
276 return NULL;
277 }
278
279 return pcidev_path_behind(bridge->downstream, devfn);
280 }
281
pcidev_path_on_root_debug(pci_devfn_t devfn,const char * func)282 DEVTREE_CONST struct device *pcidev_path_on_root_debug(pci_devfn_t devfn, const char *func)
283 {
284 DEVTREE_CONST struct device *dev = pcidev_path_on_root(devfn);
285 if (dev)
286 return dev;
287
288 devtree_bug(func, devfn);
289
290 /* FIXME: This can return wrong device. */
291 return dev_find_slot(0, devfn);
292 }
293
devtree_bug(const char * func,pci_devfn_t devfn)294 void devtree_bug(const char *func, pci_devfn_t devfn)
295 {
296 printk(BIOS_ERR, "BUG: %s requests hidden 00:%02x.%u\n", func, devfn >> 3, devfn & 7);
297 }
298
devtree_die(void)299 void __noreturn devtree_die(void)
300 {
301 die("DEVTREE: dev or chip_info is NULL\n");
302 }
303
304 /**
305 * Given an SMBus bus and a device number, find the device structure.
306 *
307 * @param bus The bus number.
308 * @param addr A device number.
309 * @return Pointer to the device structure (if found), 0 otherwise.
310 */
dev_find_slot_on_smbus(unsigned int bus,unsigned int addr)311 DEVTREE_CONST struct device *dev_find_slot_on_smbus(unsigned int bus,
312 unsigned int addr)
313 {
314 DEVTREE_CONST struct device *dev, *result;
315
316 result = 0;
317 for (dev = all_devices; dev; dev = dev->next) {
318 if ((dev->path.type == DEVICE_PATH_I2C) &&
319 (dev->upstream->secondary == bus) &&
320 (dev->path.i2c.device == addr)) {
321 result = dev;
322 break;
323 }
324 }
325 return result;
326 }
327
328 /**
329 * Given a PnP port and a device number, find the device structure.
330 *
331 * @param port The I/O port.
332 * @param device Logical device number.
333 * @return Pointer to the device structure (if found), 0 otherwise.
334 */
dev_find_slot_pnp(u16 port,u16 device)335 DEVTREE_CONST struct device *dev_find_slot_pnp(u16 port, u16 device)
336 {
337 DEVTREE_CONST struct device *dev;
338
339 for (dev = all_devices; dev; dev = dev->next) {
340 if ((dev->path.type == DEVICE_PATH_PNP) &&
341 (dev->path.pnp.port == port) &&
342 (dev->path.pnp.device == device)) {
343 return dev;
344 }
345 }
346 return 0;
347 }
348
349 /**
350 * Given a device and previous match iterate through all the children.
351 *
352 * @param bus parent device's bus holding all the children
353 * @param prev_child previous child already traversed, if NULL start at
354 * children of parent bus.
355 * @return pointer to child or NULL when no more children
356 */
dev_bus_each_child(const struct bus * parent,DEVTREE_CONST struct device * prev_child)357 DEVTREE_CONST struct device *dev_bus_each_child(const struct bus *parent,
358 DEVTREE_CONST struct device *prev_child)
359 {
360 DEVTREE_CONST struct device *dev;
361
362 if (parent == NULL)
363 return NULL;
364
365 if (prev_child == NULL)
366 dev = parent->children;
367 else
368 dev = prev_child->sibling;
369
370 return dev;
371 }
372
is_dev_enabled(const struct device * dev)373 bool is_dev_enabled(const struct device *dev)
374 {
375 if (!dev)
376 return false;
377
378 /* For stages with immutable device tree, first check if device is disabled because of
379 fw_config probing. In these stages, dev->enabled does not reflect the true state of a
380 device that uses fw_config probing. */
381 if (DEVTREE_EARLY && !fw_config_probe_dev(dev, NULL))
382 return false;
383 return dev->enabled;
384 }
385
is_devfn_enabled(unsigned int devfn)386 bool is_devfn_enabled(unsigned int devfn)
387 {
388 const struct device *dev = pcidev_path_on_root(devfn);
389 return is_dev_enabled(dev);
390 }
391