xref: /openbmc/linux/drivers/gpu/drm/i915/i915_sysfs.c (revision 55b37d9c)
1 /*
2  * Copyright © 2012 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 DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Ben Widawsky <ben@bwidawsk.net>
25  *
26  */
27 
28 #include <linux/device.h>
29 #include <linux/module.h>
30 #include <linux/stat.h>
31 #include <linux/sysfs.h>
32 
33 #include "gt/intel_gt_regs.h"
34 #include "gt/intel_rc6.h"
35 #include "gt/intel_rps.h"
36 #include "gt/sysfs_engines.h"
37 
38 #include "i915_drv.h"
39 #include "i915_sysfs.h"
40 
41 struct drm_i915_private *kdev_minor_to_i915(struct device *kdev)
42 {
43 	struct drm_minor *minor = dev_get_drvdata(kdev);
44 	return to_i915(minor->dev);
45 }
46 
47 static int l3_access_valid(struct drm_i915_private *i915, loff_t offset)
48 {
49 	if (!HAS_L3_DPF(i915))
50 		return -EPERM;
51 
52 	if (!IS_ALIGNED(offset, sizeof(u32)))
53 		return -EINVAL;
54 
55 	if (offset >= GEN7_L3LOG_SIZE)
56 		return -ENXIO;
57 
58 	return 0;
59 }
60 
61 static ssize_t
62 i915_l3_read(struct file *filp, struct kobject *kobj,
63 	     struct bin_attribute *attr, char *buf,
64 	     loff_t offset, size_t count)
65 {
66 	struct device *kdev = kobj_to_dev(kobj);
67 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
68 	int slice = (int)(uintptr_t)attr->private;
69 	int ret;
70 
71 	ret = l3_access_valid(i915, offset);
72 	if (ret)
73 		return ret;
74 
75 	count = round_down(count, sizeof(u32));
76 	count = min_t(size_t, GEN7_L3LOG_SIZE - offset, count);
77 	memset(buf, 0, count);
78 
79 	spin_lock(&i915->gem.contexts.lock);
80 	if (i915->l3_parity.remap_info[slice])
81 		memcpy(buf,
82 		       i915->l3_parity.remap_info[slice] + offset / sizeof(u32),
83 		       count);
84 	spin_unlock(&i915->gem.contexts.lock);
85 
86 	return count;
87 }
88 
89 static ssize_t
90 i915_l3_write(struct file *filp, struct kobject *kobj,
91 	      struct bin_attribute *attr, char *buf,
92 	      loff_t offset, size_t count)
93 {
94 	struct device *kdev = kobj_to_dev(kobj);
95 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
96 	int slice = (int)(uintptr_t)attr->private;
97 	u32 *remap_info, *freeme = NULL;
98 	struct i915_gem_context *ctx;
99 	int ret;
100 
101 	ret = l3_access_valid(i915, offset);
102 	if (ret)
103 		return ret;
104 
105 	if (count < sizeof(u32))
106 		return -EINVAL;
107 
108 	remap_info = kzalloc(GEN7_L3LOG_SIZE, GFP_KERNEL);
109 	if (!remap_info)
110 		return -ENOMEM;
111 
112 	spin_lock(&i915->gem.contexts.lock);
113 
114 	if (i915->l3_parity.remap_info[slice]) {
115 		freeme = remap_info;
116 		remap_info = i915->l3_parity.remap_info[slice];
117 	} else {
118 		i915->l3_parity.remap_info[slice] = remap_info;
119 	}
120 
121 	count = round_down(count, sizeof(u32));
122 	memcpy(remap_info + offset / sizeof(u32), buf, count);
123 
124 	/* NB: We defer the remapping until we switch to the context */
125 	list_for_each_entry(ctx, &i915->gem.contexts.list, link)
126 		ctx->remap_slice |= BIT(slice);
127 
128 	spin_unlock(&i915->gem.contexts.lock);
129 	kfree(freeme);
130 
131 	/*
132 	 * TODO: Ideally we really want a GPU reset here to make sure errors
133 	 * aren't propagated. Since I cannot find a stable way to reset the GPU
134 	 * at this point it is left as a TODO.
135 	*/
136 
137 	return count;
138 }
139 
140 static const struct bin_attribute dpf_attrs = {
141 	.attr = {.name = "l3_parity", .mode = (S_IRUSR | S_IWUSR)},
142 	.size = GEN7_L3LOG_SIZE,
143 	.read = i915_l3_read,
144 	.write = i915_l3_write,
145 	.mmap = NULL,
146 	.private = (void *)0
147 };
148 
149 static const struct bin_attribute dpf_attrs_1 = {
150 	.attr = {.name = "l3_parity_slice_1", .mode = (S_IRUSR | S_IWUSR)},
151 	.size = GEN7_L3LOG_SIZE,
152 	.read = i915_l3_read,
153 	.write = i915_l3_write,
154 	.mmap = NULL,
155 	.private = (void *)1
156 };
157 
158 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
159 
160 static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
161 				struct bin_attribute *attr, char *buf,
162 				loff_t off, size_t count)
163 {
164 
165 	struct device *kdev = kobj_to_dev(kobj);
166 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
167 	struct i915_gpu_coredump *gpu;
168 	ssize_t ret = 0;
169 
170 	/*
171 	 * FIXME: Concurrent clients triggering resets and reading + clearing
172 	 * dumps can cause inconsistent sysfs reads when a user calls in with a
173 	 * non-zero offset to complete a prior partial read but the
174 	 * gpu_coredump has been cleared or replaced.
175 	 */
176 
177 	gpu = i915_first_error_state(i915);
178 	if (IS_ERR(gpu)) {
179 		ret = PTR_ERR(gpu);
180 	} else if (gpu) {
181 		ret = i915_gpu_coredump_copy_to_buffer(gpu, buf, off, count);
182 		i915_gpu_coredump_put(gpu);
183 	} else {
184 		const char *str = "No error state collected\n";
185 		size_t len = strlen(str);
186 
187 		if (off < len) {
188 			ret = min_t(size_t, count, len - off);
189 			memcpy(buf, str + off, ret);
190 		}
191 	}
192 
193 	return ret;
194 }
195 
196 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
197 				 struct bin_attribute *attr, char *buf,
198 				 loff_t off, size_t count)
199 {
200 	struct device *kdev = kobj_to_dev(kobj);
201 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
202 
203 	drm_dbg(&dev_priv->drm, "Resetting error state\n");
204 	i915_reset_error_state(dev_priv);
205 
206 	return count;
207 }
208 
209 static const struct bin_attribute error_state_attr = {
210 	.attr.name = "error",
211 	.attr.mode = S_IRUSR | S_IWUSR,
212 	.size = 0,
213 	.read = error_state_read,
214 	.write = error_state_write,
215 };
216 
217 static void i915_setup_error_capture(struct device *kdev)
218 {
219 	if (sysfs_create_bin_file(&kdev->kobj, &error_state_attr))
220 		drm_err(&kdev_minor_to_i915(kdev)->drm,
221 			"error_state sysfs setup failed\n");
222 }
223 
224 static void i915_teardown_error_capture(struct device *kdev)
225 {
226 	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
227 }
228 #else
229 static void i915_setup_error_capture(struct device *kdev) {}
230 static void i915_teardown_error_capture(struct device *kdev) {}
231 #endif
232 
233 void i915_setup_sysfs(struct drm_i915_private *dev_priv)
234 {
235 	struct device *kdev = dev_priv->drm.primary->kdev;
236 	int ret;
237 
238 	if (HAS_L3_DPF(dev_priv)) {
239 		ret = device_create_bin_file(kdev, &dpf_attrs);
240 		if (ret)
241 			drm_err(&dev_priv->drm,
242 				"l3 parity sysfs setup failed\n");
243 
244 		if (NUM_L3_SLICES(dev_priv) > 1) {
245 			ret = device_create_bin_file(kdev,
246 						     &dpf_attrs_1);
247 			if (ret)
248 				drm_err(&dev_priv->drm,
249 					"l3 parity slice 1 setup failed\n");
250 		}
251 	}
252 
253 	dev_priv->sysfs_gt = kobject_create_and_add("gt", &kdev->kobj);
254 	if (!dev_priv->sysfs_gt)
255 		drm_warn(&dev_priv->drm,
256 			 "failed to register GT sysfs directory\n");
257 
258 	i915_setup_error_capture(kdev);
259 
260 	intel_engines_add_sysfs(dev_priv);
261 }
262 
263 void i915_teardown_sysfs(struct drm_i915_private *dev_priv)
264 {
265 	struct device *kdev = dev_priv->drm.primary->kdev;
266 
267 	i915_teardown_error_capture(kdev);
268 
269 	device_remove_bin_file(kdev,  &dpf_attrs_1);
270 	device_remove_bin_file(kdev,  &dpf_attrs);
271 
272 	kobject_put(dev_priv->sysfs_gt);
273 }
274