xref: /openbmc/linux/drivers/gpu/drm/drm_print.c (revision b830f94f)
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 <stdarg.h>
29 
30 #include <linux/io.h>
31 #include <linux/seq_file.h>
32 #include <linux/slab.h>
33 
34 #include <drm/drm.h>
35 #include <drm/drm_drv.h>
36 #include <drm/drm_print.h>
37 
38 void __drm_puts_coredump(struct drm_printer *p, const char *str)
39 {
40 	struct drm_print_iterator *iterator = p->arg;
41 	ssize_t len;
42 
43 	if (!iterator->remain)
44 		return;
45 
46 	if (iterator->offset < iterator->start) {
47 		ssize_t copy;
48 
49 		len = strlen(str);
50 
51 		if (iterator->offset + len <= iterator->start) {
52 			iterator->offset += len;
53 			return;
54 		}
55 
56 		copy = len - (iterator->start - iterator->offset);
57 
58 		if (copy > iterator->remain)
59 			copy = iterator->remain;
60 
61 		/* Copy out the bit of the string that we need */
62 		memcpy(iterator->data,
63 			str + (iterator->start - iterator->offset), copy);
64 
65 		iterator->offset = iterator->start + copy;
66 		iterator->remain -= copy;
67 	} else {
68 		ssize_t pos = iterator->offset - iterator->start;
69 
70 		len = min_t(ssize_t, strlen(str), iterator->remain);
71 
72 		memcpy(iterator->data + pos, str, len);
73 
74 		iterator->offset += len;
75 		iterator->remain -= len;
76 	}
77 }
78 EXPORT_SYMBOL(__drm_puts_coredump);
79 
80 void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
81 {
82 	struct drm_print_iterator *iterator = p->arg;
83 	size_t len;
84 	char *buf;
85 
86 	if (!iterator->remain)
87 		return;
88 
89 	/* Figure out how big the string will be */
90 	len = snprintf(NULL, 0, "%pV", vaf);
91 
92 	/* This is the easiest path, we've already advanced beyond the offset */
93 	if (iterator->offset + len <= iterator->start) {
94 		iterator->offset += len;
95 		return;
96 	}
97 
98 	/* Then check if we can directly copy into the target buffer */
99 	if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
100 		ssize_t pos = iterator->offset - iterator->start;
101 
102 		snprintf(((char *) iterator->data) + pos,
103 			iterator->remain, "%pV", vaf);
104 
105 		iterator->offset += len;
106 		iterator->remain -= len;
107 
108 		return;
109 	}
110 
111 	/*
112 	 * Finally, hit the slow path and make a temporary string to copy over
113 	 * using _drm_puts_coredump
114 	 */
115 	buf = kmalloc(len + 1, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
116 	if (!buf)
117 		return;
118 
119 	snprintf(buf, len + 1, "%pV", vaf);
120 	__drm_puts_coredump(p, (const char *) buf);
121 
122 	kfree(buf);
123 }
124 EXPORT_SYMBOL(__drm_printfn_coredump);
125 
126 void __drm_puts_seq_file(struct drm_printer *p, const char *str)
127 {
128 	seq_puts(p->arg, str);
129 }
130 EXPORT_SYMBOL(__drm_puts_seq_file);
131 
132 void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
133 {
134 	seq_printf(p->arg, "%pV", vaf);
135 }
136 EXPORT_SYMBOL(__drm_printfn_seq_file);
137 
138 void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
139 {
140 	dev_info(p->arg, "[" DRM_NAME "] %pV", vaf);
141 }
142 EXPORT_SYMBOL(__drm_printfn_info);
143 
144 void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf)
145 {
146 	pr_debug("%s %pV", p->prefix, vaf);
147 }
148 EXPORT_SYMBOL(__drm_printfn_debug);
149 
150 /**
151  * drm_puts - print a const string to a &drm_printer stream
152  * @p: the &drm printer
153  * @str: const string
154  *
155  * Allow &drm_printer types that have a constant string
156  * option to use it.
157  */
158 void drm_puts(struct drm_printer *p, const char *str)
159 {
160 	if (p->puts)
161 		p->puts(p, str);
162 	else
163 		drm_printf(p, "%s", str);
164 }
165 EXPORT_SYMBOL(drm_puts);
166 
167 /**
168  * drm_printf - print to a &drm_printer stream
169  * @p: the &drm_printer
170  * @f: format string
171  */
172 void drm_printf(struct drm_printer *p, const char *f, ...)
173 {
174 	va_list args;
175 
176 	va_start(args, f);
177 	drm_vprintf(p, f, &args);
178 	va_end(args);
179 }
180 EXPORT_SYMBOL(drm_printf);
181 
182 void drm_dev_printk(const struct device *dev, const char *level,
183 		    const char *format, ...)
184 {
185 	struct va_format vaf;
186 	va_list args;
187 
188 	va_start(args, format);
189 	vaf.fmt = format;
190 	vaf.va = &args;
191 
192 	if (dev)
193 		dev_printk(level, dev, "[" DRM_NAME ":%ps] %pV",
194 			   __builtin_return_address(0), &vaf);
195 	else
196 		printk("%s" "[" DRM_NAME ":%ps] %pV",
197 		       level, __builtin_return_address(0), &vaf);
198 
199 	va_end(args);
200 }
201 EXPORT_SYMBOL(drm_dev_printk);
202 
203 void drm_dev_dbg(const struct device *dev, unsigned int category,
204 		 const char *format, ...)
205 {
206 	struct va_format vaf;
207 	va_list args;
208 
209 	if (!(drm_debug & category))
210 		return;
211 
212 	va_start(args, format);
213 	vaf.fmt = format;
214 	vaf.va = &args;
215 
216 	if (dev)
217 		dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":%ps] %pV",
218 			   __builtin_return_address(0), &vaf);
219 	else
220 		printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
221 		       __builtin_return_address(0), &vaf);
222 
223 	va_end(args);
224 }
225 EXPORT_SYMBOL(drm_dev_dbg);
226 
227 void drm_dbg(unsigned int category, const char *format, ...)
228 {
229 	struct va_format vaf;
230 	va_list args;
231 
232 	if (!(drm_debug & category))
233 		return;
234 
235 	va_start(args, format);
236 	vaf.fmt = format;
237 	vaf.va = &args;
238 
239 	printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
240 	       __builtin_return_address(0), &vaf);
241 
242 	va_end(args);
243 }
244 EXPORT_SYMBOL(drm_dbg);
245 
246 void drm_err(const char *format, ...)
247 {
248 	struct va_format vaf;
249 	va_list args;
250 
251 	va_start(args, format);
252 	vaf.fmt = format;
253 	vaf.va = &args;
254 
255 	printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV",
256 	       __builtin_return_address(0), &vaf);
257 
258 	va_end(args);
259 }
260 EXPORT_SYMBOL(drm_err);
261 
262 /**
263  * drm_print_regset32 - print the contents of registers to a
264  * &drm_printer stream.
265  *
266  * @p: the &drm printer
267  * @regset: the list of registers to print.
268  *
269  * Often in driver debug, it's useful to be able to either capture the
270  * contents of registers in the steady state using debugfs or at
271  * specific points during operation.  This lets the driver have a
272  * single list of registers for both.
273  */
274 void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset)
275 {
276 	int namelen = 0;
277 	int i;
278 
279 	for (i = 0; i < regset->nregs; i++)
280 		namelen = max(namelen, (int)strlen(regset->regs[i].name));
281 
282 	for (i = 0; i < regset->nregs; i++) {
283 		drm_printf(p, "%*s = 0x%08x\n",
284 			   namelen, regset->regs[i].name,
285 			   readl(regset->base + regset->regs[i].offset));
286 	}
287 }
288 EXPORT_SYMBOL(drm_print_regset32);
289