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 #define DEBUG /* for pr_debug() */
27 
28 #include <linux/stdarg.h>
29 
30 #include <linux/io.h>
31 #include <linux/moduleparam.h>
32 #include <linux/seq_file.h>
33 #include <linux/slab.h>
34 
35 #include <drm/drm.h>
36 #include <drm/drm_drv.h>
37 #include <drm/drm_print.h>
38 
39 /*
40  * __drm_debug: Enable debug output.
41  * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
42  */
43 unsigned int __drm_debug;
44 EXPORT_SYMBOL(__drm_debug);
45 
46 MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
47 "\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n"
48 "\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n"
49 "\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n"
50 "\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n"
51 "\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n"
52 "\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n"
53 "\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n"
54 "\t\tBit 8 (0x100) will enable DP messages (displayport code)");
55 module_param_named(debug, __drm_debug, int, 0600);
56 
__drm_puts_coredump(struct drm_printer * p,const char * str)57 void __drm_puts_coredump(struct drm_printer *p, const char *str)
58 {
59 	struct drm_print_iterator *iterator = p->arg;
60 	ssize_t len;
61 
62 	if (!iterator->remain)
63 		return;
64 
65 	if (iterator->offset < iterator->start) {
66 		ssize_t copy;
67 
68 		len = strlen(str);
69 
70 		if (iterator->offset + len <= iterator->start) {
71 			iterator->offset += len;
72 			return;
73 		}
74 
75 		copy = len - (iterator->start - iterator->offset);
76 
77 		if (copy > iterator->remain)
78 			copy = iterator->remain;
79 
80 		/* Copy out the bit of the string that we need */
81 		memcpy(iterator->data,
82 			str + (iterator->start - iterator->offset), copy);
83 
84 		iterator->offset = iterator->start + copy;
85 		iterator->remain -= copy;
86 	} else {
87 		ssize_t pos = iterator->offset - iterator->start;
88 
89 		len = min_t(ssize_t, strlen(str), iterator->remain);
90 
91 		memcpy(iterator->data + pos, str, len);
92 
93 		iterator->offset += len;
94 		iterator->remain -= len;
95 	}
96 }
97 EXPORT_SYMBOL(__drm_puts_coredump);
98 
__drm_printfn_coredump(struct drm_printer * p,struct va_format * vaf)99 void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
100 {
101 	struct drm_print_iterator *iterator = p->arg;
102 	size_t len;
103 	char *buf;
104 
105 	if (!iterator->remain)
106 		return;
107 
108 	/* Figure out how big the string will be */
109 	len = snprintf(NULL, 0, "%pV", vaf);
110 
111 	/* This is the easiest path, we've already advanced beyond the offset */
112 	if (iterator->offset + len <= iterator->start) {
113 		iterator->offset += len;
114 		return;
115 	}
116 
117 	/* Then check if we can directly copy into the target buffer */
118 	if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
119 		ssize_t pos = iterator->offset - iterator->start;
120 
121 		snprintf(((char *) iterator->data) + pos,
122 			iterator->remain, "%pV", vaf);
123 
124 		iterator->offset += len;
125 		iterator->remain -= len;
126 
127 		return;
128 	}
129 
130 	/*
131 	 * Finally, hit the slow path and make a temporary string to copy over
132 	 * using _drm_puts_coredump
133 	 */
134 	buf = kmalloc(len + 1, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
135 	if (!buf)
136 		return;
137 
138 	snprintf(buf, len + 1, "%pV", vaf);
139 	__drm_puts_coredump(p, (const char *) buf);
140 
141 	kfree(buf);
142 }
143 EXPORT_SYMBOL(__drm_printfn_coredump);
144 
__drm_puts_seq_file(struct drm_printer * p,const char * str)145 void __drm_puts_seq_file(struct drm_printer *p, const char *str)
146 {
147 	seq_puts(p->arg, str);
148 }
149 EXPORT_SYMBOL(__drm_puts_seq_file);
150 
__drm_printfn_seq_file(struct drm_printer * p,struct va_format * vaf)151 void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
152 {
153 	seq_printf(p->arg, "%pV", vaf);
154 }
155 EXPORT_SYMBOL(__drm_printfn_seq_file);
156 
__drm_printfn_info(struct drm_printer * p,struct va_format * vaf)157 void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
158 {
159 	dev_info(p->arg, "[" DRM_NAME "] %pV", vaf);
160 }
161 EXPORT_SYMBOL(__drm_printfn_info);
162 
__drm_printfn_debug(struct drm_printer * p,struct va_format * vaf)163 void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf)
164 {
165 	pr_debug("%s %pV", p->prefix, vaf);
166 }
167 EXPORT_SYMBOL(__drm_printfn_debug);
168 
__drm_printfn_err(struct drm_printer * p,struct va_format * vaf)169 void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf)
170 {
171 	pr_err("*ERROR* %s %pV", p->prefix, vaf);
172 }
173 EXPORT_SYMBOL(__drm_printfn_err);
174 
175 /**
176  * drm_puts - print a const string to a &drm_printer stream
177  * @p: the &drm printer
178  * @str: const string
179  *
180  * Allow &drm_printer types that have a constant string
181  * option to use it.
182  */
drm_puts(struct drm_printer * p,const char * str)183 void drm_puts(struct drm_printer *p, const char *str)
184 {
185 	if (p->puts)
186 		p->puts(p, str);
187 	else
188 		drm_printf(p, "%s", str);
189 }
190 EXPORT_SYMBOL(drm_puts);
191 
192 /**
193  * drm_printf - print to a &drm_printer stream
194  * @p: the &drm_printer
195  * @f: format string
196  */
drm_printf(struct drm_printer * p,const char * f,...)197 void drm_printf(struct drm_printer *p, const char *f, ...)
198 {
199 	va_list args;
200 
201 	va_start(args, f);
202 	drm_vprintf(p, f, &args);
203 	va_end(args);
204 }
205 EXPORT_SYMBOL(drm_printf);
206 
207 /**
208  * drm_print_bits - print bits to a &drm_printer stream
209  *
210  * Print bits (in flag fields for example) in human readable form.
211  *
212  * @p: the &drm_printer
213  * @value: field value.
214  * @bits: Array with bit names.
215  * @nbits: Size of bit names array.
216  */
drm_print_bits(struct drm_printer * p,unsigned long value,const char * const bits[],unsigned int nbits)217 void drm_print_bits(struct drm_printer *p, unsigned long value,
218 		    const char * const bits[], unsigned int nbits)
219 {
220 	bool first = true;
221 	unsigned int i;
222 
223 	if (WARN_ON_ONCE(nbits > BITS_PER_TYPE(value)))
224 		nbits = BITS_PER_TYPE(value);
225 
226 	for_each_set_bit(i, &value, nbits) {
227 		if (WARN_ON_ONCE(!bits[i]))
228 			continue;
229 		drm_printf(p, "%s%s", first ? "" : ",",
230 			   bits[i]);
231 		first = false;
232 	}
233 	if (first)
234 		drm_printf(p, "(none)");
235 }
236 EXPORT_SYMBOL(drm_print_bits);
237 
drm_dev_printk(const struct device * dev,const char * level,const char * format,...)238 void drm_dev_printk(const struct device *dev, const char *level,
239 		    const char *format, ...)
240 {
241 	struct va_format vaf;
242 	va_list args;
243 
244 	va_start(args, format);
245 	vaf.fmt = format;
246 	vaf.va = &args;
247 
248 	if (dev)
249 		dev_printk(level, dev, "[" DRM_NAME ":%ps] %pV",
250 			   __builtin_return_address(0), &vaf);
251 	else
252 		printk("%s" "[" DRM_NAME ":%ps] %pV",
253 		       level, __builtin_return_address(0), &vaf);
254 
255 	va_end(args);
256 }
257 EXPORT_SYMBOL(drm_dev_printk);
258 
drm_dev_dbg(const struct device * dev,enum drm_debug_category category,const char * format,...)259 void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
260 		 const char *format, ...)
261 {
262 	struct va_format vaf;
263 	va_list args;
264 
265 	if (!drm_debug_enabled(category))
266 		return;
267 
268 	va_start(args, format);
269 	vaf.fmt = format;
270 	vaf.va = &args;
271 
272 	if (dev)
273 		dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":%ps] %pV",
274 			   __builtin_return_address(0), &vaf);
275 	else
276 		printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
277 		       __builtin_return_address(0), &vaf);
278 
279 	va_end(args);
280 }
281 EXPORT_SYMBOL(drm_dev_dbg);
282 
__drm_dbg(enum drm_debug_category category,const char * format,...)283 void __drm_dbg(enum drm_debug_category category, const char *format, ...)
284 {
285 	struct va_format vaf;
286 	va_list args;
287 
288 	if (!drm_debug_enabled(category))
289 		return;
290 
291 	va_start(args, format);
292 	vaf.fmt = format;
293 	vaf.va = &args;
294 
295 	printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
296 	       __builtin_return_address(0), &vaf);
297 
298 	va_end(args);
299 }
300 EXPORT_SYMBOL(__drm_dbg);
301 
__drm_err(const char * format,...)302 void __drm_err(const char *format, ...)
303 {
304 	struct va_format vaf;
305 	va_list args;
306 
307 	va_start(args, format);
308 	vaf.fmt = format;
309 	vaf.va = &args;
310 
311 	printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV",
312 	       __builtin_return_address(0), &vaf);
313 
314 	va_end(args);
315 }
316 EXPORT_SYMBOL(__drm_err);
317 
318 /**
319  * drm_print_regset32 - print the contents of registers to a
320  * &drm_printer stream.
321  *
322  * @p: the &drm printer
323  * @regset: the list of registers to print.
324  *
325  * Often in driver debug, it's useful to be able to either capture the
326  * contents of registers in the steady state using debugfs or at
327  * specific points during operation.  This lets the driver have a
328  * single list of registers for both.
329  */
drm_print_regset32(struct drm_printer * p,struct debugfs_regset32 * regset)330 void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset)
331 {
332 	int namelen = 0;
333 	int i;
334 
335 	for (i = 0; i < regset->nregs; i++)
336 		namelen = max(namelen, (int)strlen(regset->regs[i].name));
337 
338 	for (i = 0; i < regset->nregs; i++) {
339 		drm_printf(p, "%*s = 0x%08x\n",
340 			   namelen, regset->regs[i].name,
341 			   readl(regset->base + regset->regs[i].offset));
342 	}
343 }
344 EXPORT_SYMBOL(drm_print_regset32);
345