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 #include "intel_pm.h"
41 
kdev_minor_to_i915(struct device * kdev)42 struct drm_i915_private *kdev_minor_to_i915(struct device *kdev)
43 {
44 	struct drm_minor *minor = dev_get_drvdata(kdev);
45 	return to_i915(minor->dev);
46 }
47 
l3_access_valid(struct drm_i915_private * i915,loff_t offset)48 static int l3_access_valid(struct drm_i915_private *i915, loff_t offset)
49 {
50 	if (!HAS_L3_DPF(i915))
51 		return -EPERM;
52 
53 	if (!IS_ALIGNED(offset, sizeof(u32)))
54 		return -EINVAL;
55 
56 	if (offset >= GEN7_L3LOG_SIZE)
57 		return -ENXIO;
58 
59 	return 0;
60 }
61 
62 static ssize_t
i915_l3_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t offset,size_t count)63 i915_l3_read(struct file *filp, struct kobject *kobj,
64 	     struct bin_attribute *attr, char *buf,
65 	     loff_t offset, size_t count)
66 {
67 	struct device *kdev = kobj_to_dev(kobj);
68 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
69 	int slice = (int)(uintptr_t)attr->private;
70 	int ret;
71 
72 	ret = l3_access_valid(i915, offset);
73 	if (ret)
74 		return ret;
75 
76 	count = round_down(count, sizeof(u32));
77 	count = min_t(size_t, GEN7_L3LOG_SIZE - offset, count);
78 	memset(buf, 0, count);
79 
80 	spin_lock(&i915->gem.contexts.lock);
81 	if (i915->l3_parity.remap_info[slice])
82 		memcpy(buf,
83 		       i915->l3_parity.remap_info[slice] + offset / sizeof(u32),
84 		       count);
85 	spin_unlock(&i915->gem.contexts.lock);
86 
87 	return count;
88 }
89 
90 static ssize_t
i915_l3_write(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t offset,size_t count)91 i915_l3_write(struct file *filp, struct kobject *kobj,
92 	      struct bin_attribute *attr, char *buf,
93 	      loff_t offset, size_t count)
94 {
95 	struct device *kdev = kobj_to_dev(kobj);
96 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
97 	int slice = (int)(uintptr_t)attr->private;
98 	u32 *remap_info, *freeme = NULL;
99 	struct i915_gem_context *ctx;
100 	int ret;
101 
102 	ret = l3_access_valid(i915, offset);
103 	if (ret)
104 		return ret;
105 
106 	if (count < sizeof(u32))
107 		return -EINVAL;
108 
109 	remap_info = kzalloc(GEN7_L3LOG_SIZE, GFP_KERNEL);
110 	if (!remap_info)
111 		return -ENOMEM;
112 
113 	spin_lock(&i915->gem.contexts.lock);
114 
115 	if (i915->l3_parity.remap_info[slice]) {
116 		freeme = remap_info;
117 		remap_info = i915->l3_parity.remap_info[slice];
118 	} else {
119 		i915->l3_parity.remap_info[slice] = remap_info;
120 	}
121 
122 	count = round_down(count, sizeof(u32));
123 	memcpy(remap_info + offset / sizeof(u32), buf, count);
124 
125 	/* NB: We defer the remapping until we switch to the context */
126 	list_for_each_entry(ctx, &i915->gem.contexts.list, link)
127 		ctx->remap_slice |= BIT(slice);
128 
129 	spin_unlock(&i915->gem.contexts.lock);
130 	kfree(freeme);
131 
132 	/*
133 	 * TODO: Ideally we really want a GPU reset here to make sure errors
134 	 * aren't propagated. Since I cannot find a stable way to reset the GPU
135 	 * at this point it is left as a TODO.
136 	*/
137 
138 	return count;
139 }
140 
141 static const struct bin_attribute dpf_attrs = {
142 	.attr = {.name = "l3_parity", .mode = (S_IRUSR | S_IWUSR)},
143 	.size = GEN7_L3LOG_SIZE,
144 	.read = i915_l3_read,
145 	.write = i915_l3_write,
146 	.mmap = NULL,
147 	.private = (void *)0
148 };
149 
150 static const struct bin_attribute dpf_attrs_1 = {
151 	.attr = {.name = "l3_parity_slice_1", .mode = (S_IRUSR | S_IWUSR)},
152 	.size = GEN7_L3LOG_SIZE,
153 	.read = i915_l3_read,
154 	.write = i915_l3_write,
155 	.mmap = NULL,
156 	.private = (void *)1
157 };
158 
159 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
160 
error_state_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)161 static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
162 				struct bin_attribute *attr, char *buf,
163 				loff_t off, size_t count)
164 {
165 
166 	struct device *kdev = kobj_to_dev(kobj);
167 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
168 	struct i915_gpu_coredump *gpu;
169 	ssize_t ret = 0;
170 
171 	/*
172 	 * FIXME: Concurrent clients triggering resets and reading + clearing
173 	 * dumps can cause inconsistent sysfs reads when a user calls in with a
174 	 * non-zero offset to complete a prior partial read but the
175 	 * gpu_coredump has been cleared or replaced.
176 	 */
177 
178 	gpu = i915_first_error_state(i915);
179 	if (IS_ERR(gpu)) {
180 		ret = PTR_ERR(gpu);
181 	} else if (gpu) {
182 		ret = i915_gpu_coredump_copy_to_buffer(gpu, buf, off, count);
183 		i915_gpu_coredump_put(gpu);
184 	} else {
185 		const char *str = "No error state collected\n";
186 		size_t len = strlen(str);
187 
188 		if (off < len) {
189 			ret = min_t(size_t, count, len - off);
190 			memcpy(buf, str + off, ret);
191 		}
192 	}
193 
194 	return ret;
195 }
196 
error_state_write(struct file * file,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)197 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
198 				 struct bin_attribute *attr, char *buf,
199 				 loff_t off, size_t count)
200 {
201 	struct device *kdev = kobj_to_dev(kobj);
202 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
203 
204 	drm_dbg(&dev_priv->drm, "Resetting error state\n");
205 	i915_reset_error_state(dev_priv);
206 
207 	return count;
208 }
209 
210 static const struct bin_attribute error_state_attr = {
211 	.attr.name = "error",
212 	.attr.mode = S_IRUSR | S_IWUSR,
213 	.size = 0,
214 	.read = error_state_read,
215 	.write = error_state_write,
216 };
217 
i915_setup_error_capture(struct device * kdev)218 static void i915_setup_error_capture(struct device *kdev)
219 {
220 	if (sysfs_create_bin_file(&kdev->kobj, &error_state_attr))
221 		drm_err(&kdev_minor_to_i915(kdev)->drm,
222 			"error_state sysfs setup failed\n");
223 }
224 
i915_teardown_error_capture(struct device * kdev)225 static void i915_teardown_error_capture(struct device *kdev)
226 {
227 	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
228 }
229 #else
i915_setup_error_capture(struct device * kdev)230 static void i915_setup_error_capture(struct device *kdev) {}
i915_teardown_error_capture(struct device * kdev)231 static void i915_teardown_error_capture(struct device *kdev) {}
232 #endif
233 
i915_setup_sysfs(struct drm_i915_private * dev_priv)234 void i915_setup_sysfs(struct drm_i915_private *dev_priv)
235 {
236 	struct device *kdev = dev_priv->drm.primary->kdev;
237 	int ret;
238 
239 	if (HAS_L3_DPF(dev_priv)) {
240 		ret = device_create_bin_file(kdev, &dpf_attrs);
241 		if (ret)
242 			drm_err(&dev_priv->drm,
243 				"l3 parity sysfs setup failed\n");
244 
245 		if (NUM_L3_SLICES(dev_priv) > 1) {
246 			ret = device_create_bin_file(kdev,
247 						     &dpf_attrs_1);
248 			if (ret)
249 				drm_err(&dev_priv->drm,
250 					"l3 parity slice 1 setup failed\n");
251 		}
252 	}
253 
254 	dev_priv->sysfs_gt = kobject_create_and_add("gt", &kdev->kobj);
255 	if (!dev_priv->sysfs_gt)
256 		drm_warn(&dev_priv->drm,
257 			 "failed to register GT sysfs directory\n");
258 
259 	i915_setup_error_capture(kdev);
260 
261 	intel_engines_add_sysfs(dev_priv);
262 }
263 
i915_teardown_sysfs(struct drm_i915_private * dev_priv)264 void i915_teardown_sysfs(struct drm_i915_private *dev_priv)
265 {
266 	struct device *kdev = dev_priv->drm.primary->kdev;
267 
268 	i915_teardown_error_capture(kdev);
269 
270 	device_remove_bin_file(kdev,  &dpf_attrs_1);
271 	device_remove_bin_file(kdev,  &dpf_attrs);
272 
273 	kobject_put(dev_priv->sysfs_gt);
274 }
275