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
 42struct 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
 48static 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
 62static ssize_t
 63i915_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
 90static ssize_t
 91i915_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
141static 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
150static 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
161static 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
197static 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
210static 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
218static 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
225static void i915_teardown_error_capture(struct device *kdev)
226{
227	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
228}
229#else
230static void i915_setup_error_capture(struct device *kdev) {}
231static void i915_teardown_error_capture(struct device *kdev) {}
232#endif
233
234void 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
264void 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}