1 /*
2  * Copyright © 2008 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Eric Anholt <eric@anholt.net>
25  *    Ben Widawsky <ben@bwidawsk.net>
26  *
27  */
28 
29 #include <unistd.h>
30 #include <fcntl.h>
31 #include <stdio.h>
32 #include <stdarg.h>
33 #include <stdlib.h>
34 #include <stdint.h>
35 #include <stdbool.h>
36 #include <string.h>
37 #include <errno.h>
38 #include <err.h>
39 #include <assert.h>
40 #include <sys/ioctl.h>
41 #include <sys/stat.h>
42 #include <sys/mman.h>
43 
44 #include "intel_io.h"
45 #include "igt_core.h"
46 #include "igt_gt.h"
47 #include "intel_chipset.h"
48 
49 /**
50  * SECTION:intel_io
51  * @short_description: Register access and sideband I/O library
52  * @title: I/O
53  * @include: igt.h
54  * @section_id: igt-gpu-tools-IO
55  *
56  * This library provides register I/O helpers in both a basic version and a more
57  * fancy version which also handles forcewake and can optionally check registers
58  * against a white-list. All register function are compatible. Hence the same
59  * code can be used to decode registers with either of them, or also from a dump
60  * file using intel_mmio_use_dump_file().
61  *
62  * Furthermore this library also provides helper functions for accessing the
63  * various sideband interfaces found on Valleyview/Baytrail based platforms.
64  */
65 
66 #define FAKEKEY 0x2468ace0
67 
68 /**
69  * igt_global_mmio:
70  *
71  * Pointer to the register range, initialized using intel_register_access_init()
72  * or intel_mmio_use_dump_file(). It is not recommended to use this directly.
73  */
74 void *igt_global_mmio;
75 
76 static struct _mmio_data {
77 	int inited;
78 	bool safe;
79 	uint32_t i915_devid;
80 	struct intel_register_map map;
81 	int key;
82 } mmio_data;
83 
84 /**
85  * intel_mmio_use_dump_file:
86  * @file: name of the register dump file to open
87  *
88  * Sets up #igt_global_mmio to point at the data contained in @file. This allows
89  * the same code to get reused for dumping and decoding from running hardware as
90  * from register dumps.
91  */
92 void
intel_mmio_use_dump_file(char * file)93 intel_mmio_use_dump_file(char *file)
94 {
95 	int fd;
96 	struct stat st;
97 
98 	fd = open(file, O_RDWR);
99 	igt_fail_on_f(fd == -1,
100 		      "Couldn't open %s\n", file);
101 
102 	fstat(fd, &st);
103 	igt_global_mmio = mmap(NULL, st.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
104 	igt_fail_on_f(igt_global_mmio == MAP_FAILED,
105 		      "Couldn't mmap %s\n", file);
106 	close(fd);
107 }
108 
109 /**
110  * intel_mmio_use_pci_bar:
111  * @pci_dev: intel gracphis pci device
112  *
113  * Sets up #igt_global_mmio to point at the mmio bar.
114  *
115  * @pci_dev can be obtained from intel_get_pci_device().
116  */
117 void
intel_mmio_use_pci_bar(struct pci_device * pci_dev)118 intel_mmio_use_pci_bar(struct pci_device *pci_dev)
119 {
120 	uint32_t devid, gen;
121 	int mmio_bar, mmio_size;
122 	int error;
123 
124 	devid = pci_dev->device_id;
125 	if (IS_GEN2(devid))
126 		mmio_bar = 1;
127 	else
128 		mmio_bar = 0;
129 
130 	gen = intel_gen(devid);
131 	if (gen < 3)
132 		mmio_size = 512*1024;
133 	else if (gen < 5)
134 		mmio_size = 512*1024;
135 	else
136 		mmio_size = 2*1024*1024;
137 
138 	error = pci_device_map_range (pci_dev,
139 				      pci_dev->regions[mmio_bar].base_addr,
140 				      mmio_size,
141 				      PCI_DEV_MAP_FLAG_WRITABLE,
142 				      &igt_global_mmio);
143 
144 	igt_fail_on_f(error != 0,
145 		      "Couldn't map MMIO region\n");
146 }
147 
148 static void
release_forcewake_lock(int fd)149 release_forcewake_lock(int fd)
150 {
151 	close(fd);
152 }
153 
154 /**
155  * intel_register_access_init:
156  * @pci_dev: intel graphics pci device
157  * @safe: use safe register access tables
158  *
159  * This initializes the new register access library, which supports forcewake
160  * handling and also allows register access to be checked with an explicit
161  * whitelist.
162  *
163  * It also initializes #igt_global_mmio like intel_mmio_use_pci_bar().
164  *
165  * @pci_dev can be obtained from intel_get_pci_device().
166  */
167 int
intel_register_access_init(struct pci_device * pci_dev,int safe,int fd)168 intel_register_access_init(struct pci_device *pci_dev, int safe, int fd)
169 {
170 	int ret;
171 
172 	/* after old API is deprecated, remove this */
173 	if (igt_global_mmio == NULL)
174 		intel_mmio_use_pci_bar(pci_dev);
175 
176 	igt_assert(igt_global_mmio != NULL);
177 
178 	if (mmio_data.inited)
179 		return -1;
180 
181 	mmio_data.safe = (safe != 0 &&
182 			intel_gen(pci_dev->device_id) >= 4) ? true : false;
183 	mmio_data.i915_devid = pci_dev->device_id;
184 	if (mmio_data.safe)
185 		mmio_data.map = intel_get_register_map(mmio_data.i915_devid);
186 
187 	/* Find where the forcewake lock is. Forcewake doesn't exist
188 	 * gen < 6, but the debugfs should do the right things for us.
189 	 */
190 	ret = igt_open_forcewake_handle(fd);
191 	if (ret == -1)
192 		mmio_data.key = FAKEKEY;
193 	else
194 		mmio_data.key = ret;
195 
196 	mmio_data.inited++;
197 	return 0;
198 }
199 
200 static int
intel_register_access_needs_wake(void)201 intel_register_access_needs_wake(void)
202 {
203 	return mmio_data.key != FAKEKEY;
204 }
205 
206 /**
207  * intel_register_access_needs_fakewake:
208  *
209  * Returns:
210  * Non-zero when forcewake initialization failed.
211  */
intel_register_access_needs_fakewake(void)212 int intel_register_access_needs_fakewake(void)
213 {
214 	return mmio_data.key == FAKEKEY;
215 }
216 
217 /**
218  * intel_register_access_fini:
219  *
220  * Clean up the register access helper initialized with
221  * intel_register_access_init().
222  */
223 void
intel_register_access_fini(void)224 intel_register_access_fini(void)
225 {
226 	if (mmio_data.key && intel_register_access_needs_wake())
227 		release_forcewake_lock(mmio_data.key);
228 	mmio_data.inited--;
229 }
230 
231 /**
232  * intel_register_read:
233  * @reg: register offset
234  *
235  * 32-bit read of the register at @offset. This function only works when the new
236  * register access helper is initialized with intel_register_access_init().
237  *
238  * Compared to INREG() it can do optional checking with the register access
239  * white lists.
240  *
241  * Returns:
242  * The value read from the register.
243  */
244 uint32_t
intel_register_read(uint32_t reg)245 intel_register_read(uint32_t reg)
246 {
247 	struct intel_register_range *range;
248 	uint32_t ret;
249 
250 	igt_assert(mmio_data.inited);
251 
252 	if (intel_gen(mmio_data.i915_devid) >= 6)
253 		igt_assert(mmio_data.key != -1);
254 
255 	if (!mmio_data.safe)
256 		goto read_out;
257 
258 	range = intel_get_register_range(mmio_data.map,
259 					 reg,
260 					 INTEL_RANGE_READ);
261 
262 	if(!range) {
263 		igt_warn("Register read blocked for safety ""(*0x%08x)\n", reg);
264 		ret = 0xffffffff;
265 		goto out;
266 	}
267 
268 read_out:
269 	ret = *(volatile uint32_t *)((volatile char *)igt_global_mmio + reg);
270 out:
271 	return ret;
272 }
273 
274 /**
275  * intel_register_write:
276  * @reg: register offset
277  * @val: value to write
278  *
279  * 32-bit write to the register at @offset. This function only works when the new
280  * register access helper is initialized with intel_register_access_init().
281  *
282  * Compared to OUTREG() it can do optional checking with the register access
283  * white lists.
284  */
285 void
intel_register_write(uint32_t reg,uint32_t val)286 intel_register_write(uint32_t reg, uint32_t val)
287 {
288 	struct intel_register_range *range;
289 
290 	igt_assert(mmio_data.inited);
291 
292 	if (intel_gen(mmio_data.i915_devid) >= 6)
293 		igt_assert(mmio_data.key != -1);
294 
295 	if (!mmio_data.safe)
296 		goto write_out;
297 
298 	range = intel_get_register_range(mmio_data.map,
299 					 reg,
300 					 INTEL_RANGE_WRITE);
301 
302 	igt_warn_on_f(!range,
303 		      "Register write blocked for safety ""(*0x%08x = 0x%x)\n", reg, val);
304 
305 write_out:
306 	*(volatile uint32_t *)((volatile char *)igt_global_mmio + reg) = val;
307 }
308 
309 
310 /**
311  * INREG:
312  * @reg: register offset
313  *
314  * 32-bit read of the register at offset @reg. This function only works when the
315  * new register access helper is initialized with intel_register_access_init().
316  *
317  * This function directly accesses the #igt_global_mmio without safety checks.
318  *
319  * Returns:
320  * The value read from the register.
321  */
INREG(uint32_t reg)322 uint32_t INREG(uint32_t reg)
323 {
324 	return *(volatile uint32_t *)((volatile char *)igt_global_mmio + reg);
325 }
326 
327 /**
328  * INREG16:
329  * @reg: register offset
330  *
331  * 16-bit read of the register at offset @reg. This function only works when the
332  * new register access helper is initialized with intel_register_access_init().
333  *
334  * This function directly accesses the #igt_global_mmio without safety checks.
335  *
336  * Returns:
337  * The value read from the register.
338  */
INREG16(uint32_t reg)339 uint16_t INREG16(uint32_t reg)
340 {
341 	return *(volatile uint16_t *)((volatile char *)igt_global_mmio + reg);
342 }
343 
344 /**
345  * INREG8:
346  * @reg: register offset
347  *
348  * 8-bit read of the register at offset @reg. This function only works when the
349  * new register access helper is initialized with intel_register_access_init().
350  *
351  * This function directly accesses the #igt_global_mmio without safety checks.
352  *
353  * Returns:
354  * The value read from the register.
355  */
INREG8(uint32_t reg)356 uint8_t INREG8(uint32_t reg)
357 {
358 	return *((volatile uint8_t *)igt_global_mmio + reg);
359 }
360 
361 /**
362  * OUTREG:
363  * @reg: register offset
364  * @val: value to write
365  *
366  * 32-bit write of @val to the register at offset @reg. This function only works
367  * when the new register access helper is initialized with
368  * intel_register_access_init().
369  *
370  * This function directly accesses the #igt_global_mmio without safety checks.
371  */
OUTREG(uint32_t reg,uint32_t val)372 void OUTREG(uint32_t reg, uint32_t val)
373 {
374 	*(volatile uint32_t *)((volatile char *)igt_global_mmio + reg) = val;
375 }
376 
377 /**
378  * OUTREG16:
379  * @reg: register offset
380  * @val: value to write
381  *
382  * 16-bit write of @val to the register at offset @reg. This function only works
383  * when the new register access helper is initialized with
384  * intel_register_access_init().
385  *
386  * This function directly accesses the #igt_global_mmio without safety checks.
387  */
OUTREG16(uint32_t reg,uint16_t val)388 void OUTREG16(uint32_t reg, uint16_t val)
389 {
390 	*(volatile uint16_t *)((volatile char *)igt_global_mmio + reg) = val;
391 }
392 
393 /**
394  * OUTREG8:
395  * @reg: register offset
396  * @val: value to write
397  *
398  * 8-bit write of @val to the register at offset @reg. This function only works
399  * when the new register access helper is initialized with
400  * intel_register_access_init().
401  *
402  * This function directly accesses the #igt_global_mmio without safety checks.
403  */
OUTREG8(uint32_t reg,uint8_t val)404 void OUTREG8(uint32_t reg, uint8_t val)
405 {
406 	*((volatile uint8_t *)igt_global_mmio + reg) = val;
407 }
408