1 /*
2  * Copyright (C) 2016 Red Hat
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 shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors:
23  * Rob Clark <robdclark@gmail.com>
24  */
25 
26 #include <linux/debugfs.h>
27 #include <linux/dynamic_debug.h>
28 #include <linux/io.h>
29 #include <linux/moduleparam.h>
30 #include <linux/seq_file.h>
31 #include <linux/slab.h>
32 #include <linux/stdarg.h>
33 
34 #include <drm/drm.h>
35 #include <drm/drm_drv.h>
36 #include <drm/drm_print.h>
37 
38 /*
39  * __drm_debug: Enable debug output.
40  * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
41  */
42 #ifdef DRMDEBUG
43 unsigned long __drm_debug = DRM_UT_DRIVER | DRM_UT_KMS;
44 #else
45 unsigned long __drm_debug;
46 #endif
47 EXPORT_SYMBOL(__drm_debug);
48 
49 MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
50 "\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n"
51 "\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n"
52 "\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n"
53 "\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n"
54 "\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n"
55 "\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n"
56 "\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n"
57 "\t\tBit 8 (0x100) will enable DP messages (displayport code)");
58 
59 #if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)
60 module_param_named(debug, __drm_debug, ulong, 0600);
61 #else
62 /* classnames must match vals of enum drm_debug_category */
63 DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
64 			"DRM_UT_CORE",
65 			"DRM_UT_DRIVER",
66 			"DRM_UT_KMS",
67 			"DRM_UT_PRIME",
68 			"DRM_UT_ATOMIC",
69 			"DRM_UT_VBL",
70 			"DRM_UT_STATE",
71 			"DRM_UT_LEASE",
72 			"DRM_UT_DP",
73 			"DRM_UT_DRMRES");
74 
75 static struct ddebug_class_param drm_debug_bitmap = {
76 	.bits = &__drm_debug,
77 	.flags = "p",
78 	.map = &drm_debug_classes,
79 };
80 module_param_cb(debug, &param_ops_dyndbg_classes, &drm_debug_bitmap, 0600);
81 #endif
82 
__drm_puts_coredump(struct drm_printer * p,const char * str)83 void __drm_puts_coredump(struct drm_printer *p, const char *str)
84 {
85 	struct drm_print_iterator *iterator = p->arg;
86 	ssize_t len;
87 
88 	if (!iterator->remain)
89 		return;
90 
91 	if (iterator->offset < iterator->start) {
92 		ssize_t copy;
93 
94 		len = strlen(str);
95 
96 		if (iterator->offset + len <= iterator->start) {
97 			iterator->offset += len;
98 			return;
99 		}
100 
101 		copy = len - (iterator->start - iterator->offset);
102 
103 		if (copy > iterator->remain)
104 			copy = iterator->remain;
105 
106 		/* Copy out the bit of the string that we need */
107 		if (iterator->data)
108 			memcpy(iterator->data,
109 			       str + (iterator->start - iterator->offset), copy);
110 
111 		iterator->offset = iterator->start + copy;
112 		iterator->remain -= copy;
113 	} else {
114 		ssize_t pos = iterator->offset - iterator->start;
115 
116 		len = min_t(ssize_t, strlen(str), iterator->remain);
117 
118 		if (iterator->data)
119 			memcpy(iterator->data + pos, str, len);
120 
121 		iterator->offset += len;
122 		iterator->remain -= len;
123 	}
124 }
125 EXPORT_SYMBOL(__drm_puts_coredump);
126 
__drm_printfn_coredump(struct drm_printer * p,struct va_format * vaf)127 void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
128 {
129 	struct drm_print_iterator *iterator = p->arg;
130 	size_t len;
131 	char *buf;
132 
133 	if (!iterator->remain)
134 		return;
135 
136 	/* Figure out how big the string will be */
137 	len = snprintf(NULL, 0, "%pV", vaf);
138 
139 	/* This is the easiest path, we've already advanced beyond the offset */
140 	if (iterator->offset + len <= iterator->start) {
141 		iterator->offset += len;
142 		return;
143 	}
144 
145 	/* Then check if we can directly copy into the target buffer */
146 	if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
147 		ssize_t pos = iterator->offset - iterator->start;
148 
149 		if (iterator->data)
150 			snprintf(((char *) iterator->data) + pos,
151 				 iterator->remain, "%pV", vaf);
152 
153 		iterator->offset += len;
154 		iterator->remain -= len;
155 
156 		return;
157 	}
158 
159 	/*
160 	 * Finally, hit the slow path and make a temporary string to copy over
161 	 * using _drm_puts_coredump
162 	 */
163 	buf = kmalloc(len + 1, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
164 	if (!buf)
165 		return;
166 
167 	snprintf(buf, len + 1, "%pV", vaf);
168 	__drm_puts_coredump(p, (const char *) buf);
169 
170 	kfree(buf);
171 }
172 EXPORT_SYMBOL(__drm_printfn_coredump);
173 
__drm_puts_seq_file(struct drm_printer * p,const char * str)174 void __drm_puts_seq_file(struct drm_printer *p, const char *str)
175 {
176 	seq_puts(p->arg, str);
177 }
178 EXPORT_SYMBOL(__drm_puts_seq_file);
179 
__drm_printfn_seq_file(struct drm_printer * p,struct va_format * vaf)180 void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
181 {
182 	seq_printf(p->arg, "%pV", vaf);
183 }
184 EXPORT_SYMBOL(__drm_printfn_seq_file);
185 
__drm_dev_vprintk(const struct device * dev,const char * level,const void * origin,const char * prefix,struct va_format * vaf)186 static void __drm_dev_vprintk(const struct device *dev, const char *level,
187 			      const void *origin, const char *prefix,
188 			      struct va_format *vaf)
189 {
190 	const char *prefix_pad = prefix ? " " : "";
191 
192 	if (!prefix)
193 		prefix = "";
194 
195 	if (dev) {
196 		if (origin)
197 			dev_printk(level, dev, "[" DRM_NAME ":%ps]%s%s %pV",
198 				   origin, prefix_pad, prefix, vaf);
199 		else
200 			dev_printk(level, dev, "[" DRM_NAME "]%s%s %pV",
201 				   prefix_pad, prefix, vaf);
202 	} else {
203 		if (origin)
204 			printk("%s" "[" DRM_NAME ":%ps]%s%s %pV",
205 			       level, origin, prefix_pad, prefix, vaf);
206 		else
207 			printk("%s" "[" DRM_NAME "]%s%s %pV",
208 			       level, prefix_pad, prefix, vaf);
209 	}
210 }
211 
212 #ifdef __linux__
__drm_printfn_info(struct drm_printer * p,struct va_format * vaf)213 void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
214 {
215 	dev_info(p->arg, "[" DRM_NAME "] %pV", vaf);
216 }
217 EXPORT_SYMBOL(__drm_printfn_info);
218 #endif
219 
__drm_printfn_dbg(struct drm_printer * p,struct va_format * vaf)220 void __drm_printfn_dbg(struct drm_printer *p, struct va_format *vaf)
221 {
222 	const struct drm_device *drm = p->arg;
223 	const struct device *dev = drm ? drm->dev : NULL;
224 	enum drm_debug_category category = p->category;
225 
226 	if (!__drm_debug_enabled(category))
227 		return;
228 
229 	__drm_dev_vprintk(dev, KERN_DEBUG, p->origin, p->prefix, vaf);
230 }
231 EXPORT_SYMBOL(__drm_printfn_dbg);
232 
233 #ifdef __linux__
__drm_printfn_err(struct drm_printer * p,struct va_format * vaf)234 void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf)
235 {
236 	struct drm_device *drm = p->arg;
237 
238 	if (p->prefix)
239 		drm_err(drm, "%s %pV", p->prefix, vaf);
240 	else
241 		drm_err(drm, "%pV", vaf);
242 }
243 EXPORT_SYMBOL(__drm_printfn_err);
244 #else
__drm_printfn_info(struct drm_printer * p,struct va_format * vaf)245 void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
246 {
247 #ifdef DRMDEBUG
248 	printf("[" DRM_NAME "] ");
249 	vprintf(vaf->fmt, *vaf->va);
250 #endif
251 }
252 
__drm_printfn_debug(struct drm_printer * p,struct va_format * vaf)253 void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf)
254 {
255 #ifdef DRMDEBUG
256 	printf("%s ", p->prefix);
257 	vprintf(vaf->fmt, *vaf->va);
258 #endif
259 }
260 
__drm_printfn_err(struct drm_printer * p,struct va_format * vaf)261 void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf)
262 {
263 	printf("*ERROR* %s ", p->prefix);
264 	vprintf(vaf->fmt, *vaf->va);
265 }
266 #endif
267 
268 /**
269  * drm_puts - print a const string to a &drm_printer stream
270  * @p: the &drm printer
271  * @str: const string
272  *
273  * Allow &drm_printer types that have a constant string
274  * option to use it.
275  */
drm_puts(struct drm_printer * p,const char * str)276 void drm_puts(struct drm_printer *p, const char *str)
277 {
278 	if (p->puts)
279 		p->puts(p, str);
280 	else
281 		drm_printf(p, "%s", str);
282 }
283 EXPORT_SYMBOL(drm_puts);
284 
285 /**
286  * drm_printf - print to a &drm_printer stream
287  * @p: the &drm_printer
288  * @f: format string
289  */
drm_printf(struct drm_printer * p,const char * f,...)290 void drm_printf(struct drm_printer *p, const char *f, ...)
291 {
292 	va_list args;
293 
294 	va_start(args, f);
295 	drm_vprintf(p, f, &args);
296 	va_end(args);
297 }
298 EXPORT_SYMBOL(drm_printf);
299 
300 /**
301  * drm_print_bits - print bits to a &drm_printer stream
302  *
303  * Print bits (in flag fields for example) in human readable form.
304  *
305  * @p: the &drm_printer
306  * @value: field value.
307  * @bits: Array with bit names.
308  * @nbits: Size of bit names array.
309  */
drm_print_bits(struct drm_printer * p,unsigned long value,const char * const bits[],unsigned int nbits)310 void drm_print_bits(struct drm_printer *p, unsigned long value,
311 		    const char * const bits[], unsigned int nbits)
312 {
313 	bool first = true;
314 	unsigned int i;
315 
316 	if (WARN_ON_ONCE(nbits > BITS_PER_TYPE(value)))
317 		nbits = BITS_PER_TYPE(value);
318 
319 	for_each_set_bit(i, &value, nbits) {
320 		if (WARN_ON_ONCE(!bits[i]))
321 			continue;
322 		drm_printf(p, "%s%s", first ? "" : ",",
323 			   bits[i]);
324 		first = false;
325 	}
326 	if (first)
327 		drm_printf(p, "(none)");
328 }
329 EXPORT_SYMBOL(drm_print_bits);
330 
331 #ifdef __linux__
drm_dev_printk(const struct device * dev,const char * level,const char * format,...)332 void drm_dev_printk(const struct device *dev, const char *level,
333 		    const char *format, ...)
334 {
335 	struct va_format vaf;
336 	va_list args;
337 
338 	va_start(args, format);
339 	vaf.fmt = format;
340 	vaf.va = &args;
341 
342 	__drm_dev_vprintk(dev, level, __builtin_return_address(0), NULL, &vaf);
343 
344 	va_end(args);
345 }
346 EXPORT_SYMBOL(drm_dev_printk);
347 
__drm_dev_dbg(struct _ddebug * desc,const struct device * dev,enum drm_debug_category category,const char * format,...)348 void __drm_dev_dbg(struct _ddebug *desc, const struct device *dev,
349 		   enum drm_debug_category category, const char *format, ...)
350 {
351 	struct va_format vaf;
352 	va_list args;
353 
354 	if (!__drm_debug_enabled(category))
355 		return;
356 
357 	/* we know we are printing for either syslog, tracefs, or both */
358 	va_start(args, format);
359 	vaf.fmt = format;
360 	vaf.va = &args;
361 
362 	__drm_dev_vprintk(dev, KERN_DEBUG, __builtin_return_address(0), NULL, &vaf);
363 
364 	va_end(args);
365 }
366 EXPORT_SYMBOL(__drm_dev_dbg);
367 
__drm_err(const char * format,...)368 void __drm_err(const char *format, ...)
369 {
370 	struct va_format vaf;
371 	va_list args;
372 
373 	va_start(args, format);
374 	vaf.fmt = format;
375 	vaf.va = &args;
376 
377 	__drm_dev_vprintk(NULL, KERN_ERR, __builtin_return_address(0), "*ERROR*", &vaf);
378 
379 	va_end(args);
380 }
381 EXPORT_SYMBOL(__drm_err);
382 
383 #else
384 
drm_dev_printk(const struct device * dev,const char * level,const char * format,...)385 void drm_dev_printk(const struct device *dev, const char *level,
386 		    const char *format, ...)
387 {
388 	va_list args;
389 
390 #ifndef DRMDEBUG
391 	if (level[0] == '\001') {
392 		if (level[1] >= KERN_INFO[1] && level[1] < '9')
393 			return;
394 	}
395 #endif
396 
397 	va_start(args, format);
398 	printk("[" DRM_NAME "] ");
399 	vprintf(format, args);
400 	va_end(args);
401 }
402 
__drm_dev_dbg(struct _ddebug * desc,const struct device * dev,enum drm_debug_category category,const char * format,...)403 void __drm_dev_dbg(struct _ddebug *desc, const struct device *dev,
404 		   enum drm_debug_category category, const char *format, ...)
405 {
406 	va_list args;
407 
408 	if (!__drm_debug_enabled(category))
409 		return;
410 
411 	/* we know we are printing for either syslog, tracefs, or both */
412 	va_start(args, format);
413 	printk(KERN_DEBUG "[" DRM_NAME "] ");
414 	vprintf(format, args);
415 	va_end(args);
416 }
417 
___drm_dbg(struct _ddebug * desc,enum drm_debug_category category,const char * format,...)418 void ___drm_dbg(struct _ddebug *desc, enum drm_debug_category category, const char *format, ...)
419 {
420 	va_list args;
421 
422 	if (!__drm_debug_enabled(category))
423 		return;
424 
425 	va_start(args, format);
426 	printk(KERN_DEBUG "[" DRM_NAME "] ");
427 	vprintf(format, args);
428 	va_end(args);
429 }
430 
__drm_err(const char * format,...)431 void __drm_err(const char *format, ...)
432 {
433 	va_list args;
434 
435 	va_start(args, format);
436 	printk(KERN_ERR "[" DRM_NAME "] *ERROR* ");
437 	vprintf(format, args);
438 	va_end(args);
439 }
440 #endif /* __linux__ */
441 
442 /**
443  * drm_print_regset32 - print the contents of registers to a
444  * &drm_printer stream.
445  *
446  * @p: the &drm printer
447  * @regset: the list of registers to print.
448  *
449  * Often in driver debug, it's useful to be able to either capture the
450  * contents of registers in the steady state using debugfs or at
451  * specific points during operation.  This lets the driver have a
452  * single list of registers for both.
453  */
drm_print_regset32(struct drm_printer * p,struct debugfs_regset32 * regset)454 void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset)
455 {
456 #ifdef __linux__
457 	int namelen = 0;
458 	int i;
459 
460 	for (i = 0; i < regset->nregs; i++)
461 		namelen = max(namelen, (int)strlen(regset->regs[i].name));
462 
463 	for (i = 0; i < regset->nregs; i++) {
464 		drm_printf(p, "%*s = 0x%08x\n",
465 			   namelen, regset->regs[i].name,
466 			   readl(regset->base + regset->regs[i].offset));
467 	}
468 #endif
469 }
470 EXPORT_SYMBOL(drm_print_regset32);
471