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50352fa7 | 1 | // SPDX-License-Identifier: GPL-2.0 |
ba82664c AS |
2 | /* |
3 | * Intel(R) Trace Hub Memory Storage Unit | |
4 | * | |
5 | * Copyright (C) 2014-2015 Intel Corporation. | |
ba82664c AS |
6 | */ |
7 | ||
8 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
9 | ||
10 | #include <linux/types.h> | |
11 | #include <linux/module.h> | |
12 | #include <linux/device.h> | |
13 | #include <linux/uaccess.h> | |
14 | #include <linux/sizes.h> | |
15 | #include <linux/printk.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/mm.h> | |
18 | #include <linux/fs.h> | |
19 | #include <linux/io.h> | |
615c164d | 20 | #include <linux/workqueue.h> |
ba82664c AS |
21 | #include <linux/dma-mapping.h> |
22 | ||
0c14dac9 LA |
23 | #ifdef CONFIG_X86 |
24 | #include <asm/set_memory.h> | |
25 | #endif | |
ba82664c | 26 | |
615c164d | 27 | #include <linux/intel_th.h> |
ba82664c AS |
28 | #include "intel_th.h" |
29 | #include "msu.h" | |
30 | ||
31 | #define msc_dev(x) (&(x)->thdev->dev) | |
32 | ||
615c164d AS |
33 | /* |
34 | * Lockout state transitions: | |
35 | * READY -> INUSE -+-> LOCKED -+-> READY -> etc. | |
36 | * \-----------/ | |
37 | * WIN_READY: window can be used by HW | |
38 | * WIN_INUSE: window is in use | |
39 | * WIN_LOCKED: window is filled up and is being processed by the buffer | |
40 | * handling code | |
41 | * | |
42 | * All state transitions happen automatically, except for the LOCKED->READY, | |
43 | * which needs to be signalled by the buffer code by calling | |
44 | * intel_th_msc_window_unlock(). | |
45 | * | |
46 | * When the interrupt handler has to switch to the next window, it checks | |
47 | * whether it's READY, and if it is, it performs the switch and tracing | |
48 | * continues. If it's LOCKED, it stops the trace. | |
49 | */ | |
50 | enum lockout_state { | |
51 | WIN_READY = 0, | |
52 | WIN_INUSE, | |
53 | WIN_LOCKED | |
54 | }; | |
55 | ||
ba82664c AS |
56 | /** |
57 | * struct msc_window - multiblock mode window descriptor | |
58 | * @entry: window list linkage (msc::win_list) | |
59 | * @pgoff: page offset into the buffer that this window starts at | |
615c164d AS |
60 | * @lockout: lockout state, see comment below |
61 | * @lo_lock: lockout state serialization | |
ba82664c | 62 | * @nr_blocks: number of blocks (pages) in this window |
fa52b3fe | 63 | * @nr_segs: number of segments in this window (<= @nr_blocks) |
76e9f438 | 64 | * @msc: pointer to the MSC device |
bbbc08a1 | 65 | * @_sgt: array of block descriptors |
ba39bd83 | 66 | * @sgt: array of block descriptors |
ba82664c AS |
67 | */ |
68 | struct msc_window { | |
69 | struct list_head entry; | |
70 | unsigned long pgoff; | |
615c164d AS |
71 | enum lockout_state lockout; |
72 | spinlock_t lo_lock; | |
ba82664c | 73 | unsigned int nr_blocks; |
fa52b3fe | 74 | unsigned int nr_segs; |
ba82664c | 75 | struct msc *msc; |
bbbc08a1 AS |
76 | struct sg_table _sgt; |
77 | struct sg_table *sgt; | |
ba82664c AS |
78 | }; |
79 | ||
80 | /** | |
81 | * struct msc_iter - iterator for msc buffer | |
82 | * @entry: msc::iter_list linkage | |
83 | * @msc: pointer to the MSC device | |
84 | * @start_win: oldest window | |
85 | * @win: current window | |
86 | * @offset: current logical offset into the buffer | |
87 | * @start_block: oldest block in the window | |
88 | * @block: block number in the window | |
89 | * @block_off: offset into current block | |
90 | * @wrap_count: block wrapping handling | |
91 | * @eof: end of buffer reached | |
92 | */ | |
93 | struct msc_iter { | |
94 | struct list_head entry; | |
95 | struct msc *msc; | |
96 | struct msc_window *start_win; | |
97 | struct msc_window *win; | |
98 | unsigned long offset; | |
57b69a1f AS |
99 | struct scatterlist *start_block; |
100 | struct scatterlist *block; | |
ba82664c AS |
101 | unsigned int block_off; |
102 | unsigned int wrap_count; | |
103 | unsigned int eof; | |
104 | }; | |
105 | ||
106 | /** | |
107 | * struct msc - MSC device representation | |
108 | * @reg_base: register window base address | |
109 | * @thdev: intel_th_device pointer | |
615c164d AS |
110 | * @mbuf: MSU buffer, if assigned |
111 | * @mbuf_priv MSU buffer's private data, if @mbuf | |
ba82664c | 112 | * @win_list: list of windows in multiblock mode |
4e0eaf23 | 113 | * @single_sgt: single mode buffer |
aad14ad3 | 114 | * @cur_win: current window |
ba82664c AS |
115 | * @nr_pages: total number of pages allocated for this buffer |
116 | * @single_sz: amount of data in single mode | |
117 | * @single_wrap: single mode wrap occurred | |
118 | * @base: buffer's base pointer | |
119 | * @base_addr: buffer's base address | |
120 | * @user_count: number of users of the buffer | |
121 | * @mmap_count: number of mappings | |
122 | * @buf_mutex: mutex to serialize access to buffer-related bits | |
ba82664c AS |
123 | * @enabled: MSC is enabled |
124 | * @wrap: wrapping is enabled | |
125 | * @mode: MSC operating mode | |
126 | * @burst_len: write burst length | |
127 | * @index: number of this MSC in the MSU | |
128 | */ | |
129 | struct msc { | |
130 | void __iomem *reg_base; | |
aac8da65 | 131 | void __iomem *msu_base; |
ba82664c AS |
132 | struct intel_th_device *thdev; |
133 | ||
615c164d AS |
134 | const struct msu_buffer *mbuf; |
135 | void *mbuf_priv; | |
136 | ||
137 | struct work_struct work; | |
ba82664c | 138 | struct list_head win_list; |
4e0eaf23 | 139 | struct sg_table single_sgt; |
aad14ad3 | 140 | struct msc_window *cur_win; |
8622dfef | 141 | struct msc_window *switch_on_unlock; |
ba82664c AS |
142 | unsigned long nr_pages; |
143 | unsigned long single_sz; | |
144 | unsigned int single_wrap : 1; | |
145 | void *base; | |
146 | dma_addr_t base_addr; | |
092f47c3 AS |
147 | u32 orig_addr; |
148 | u32 orig_sz; | |
ba82664c AS |
149 | |
150 | /* <0: no buffer, 0: no users, >0: active users */ | |
151 | atomic_t user_count; | |
152 | ||
153 | atomic_t mmap_count; | |
154 | struct mutex buf_mutex; | |
155 | ||
ba82664c AS |
156 | struct list_head iter_list; |
157 | ||
8622dfef AS |
158 | bool stop_on_full; |
159 | ||
ba82664c AS |
160 | /* config */ |
161 | unsigned int enabled : 1, | |
aac8da65 | 162 | wrap : 1, |
397c7729 AS |
163 | do_irq : 1, |
164 | multi_is_broken : 1; | |
ba82664c AS |
165 | unsigned int mode; |
166 | unsigned int burst_len; | |
167 | unsigned int index; | |
168 | }; | |
169 | ||
615c164d | 170 | static LIST_HEAD(msu_buffer_list); |
e5a340f7 | 171 | static DEFINE_MUTEX(msu_buffer_mutex); |
615c164d AS |
172 | |
173 | /** | |
174 | * struct msu_buffer_entry - internal MSU buffer bookkeeping | |
175 | * @entry: link to msu_buffer_list | |
176 | * @mbuf: MSU buffer object | |
177 | * @owner: module that provides this MSU buffer | |
178 | */ | |
179 | struct msu_buffer_entry { | |
180 | struct list_head entry; | |
181 | const struct msu_buffer *mbuf; | |
182 | struct module *owner; | |
183 | }; | |
184 | ||
185 | static struct msu_buffer_entry *__msu_buffer_entry_find(const char *name) | |
186 | { | |
187 | struct msu_buffer_entry *mbe; | |
188 | ||
189 | lockdep_assert_held(&msu_buffer_mutex); | |
190 | ||
191 | list_for_each_entry(mbe, &msu_buffer_list, entry) { | |
192 | if (!strcmp(mbe->mbuf->name, name)) | |
193 | return mbe; | |
194 | } | |
195 | ||
196 | return NULL; | |
197 | } | |
198 | ||
199 | static const struct msu_buffer * | |
200 | msu_buffer_get(const char *name) | |
201 | { | |
202 | struct msu_buffer_entry *mbe; | |
203 | ||
204 | mutex_lock(&msu_buffer_mutex); | |
205 | mbe = __msu_buffer_entry_find(name); | |
206 | if (mbe && !try_module_get(mbe->owner)) | |
207 | mbe = NULL; | |
208 | mutex_unlock(&msu_buffer_mutex); | |
209 | ||
210 | return mbe ? mbe->mbuf : NULL; | |
211 | } | |
212 | ||
213 | static void msu_buffer_put(const struct msu_buffer *mbuf) | |
214 | { | |
215 | struct msu_buffer_entry *mbe; | |
216 | ||
217 | mutex_lock(&msu_buffer_mutex); | |
218 | mbe = __msu_buffer_entry_find(mbuf->name); | |
219 | if (mbe) | |
220 | module_put(mbe->owner); | |
221 | mutex_unlock(&msu_buffer_mutex); | |
222 | } | |
223 | ||
224 | int intel_th_msu_buffer_register(const struct msu_buffer *mbuf, | |
225 | struct module *owner) | |
226 | { | |
227 | struct msu_buffer_entry *mbe; | |
228 | int ret = 0; | |
229 | ||
230 | mbe = kzalloc(sizeof(*mbe), GFP_KERNEL); | |
231 | if (!mbe) | |
232 | return -ENOMEM; | |
233 | ||
234 | mutex_lock(&msu_buffer_mutex); | |
235 | if (__msu_buffer_entry_find(mbuf->name)) { | |
236 | ret = -EEXIST; | |
237 | kfree(mbe); | |
238 | goto unlock; | |
239 | } | |
240 | ||
241 | mbe->mbuf = mbuf; | |
242 | mbe->owner = owner; | |
243 | list_add_tail(&mbe->entry, &msu_buffer_list); | |
244 | unlock: | |
245 | mutex_unlock(&msu_buffer_mutex); | |
246 | ||
247 | return ret; | |
248 | } | |
249 | EXPORT_SYMBOL_GPL(intel_th_msu_buffer_register); | |
250 | ||
251 | void intel_th_msu_buffer_unregister(const struct msu_buffer *mbuf) | |
252 | { | |
253 | struct msu_buffer_entry *mbe; | |
254 | ||
255 | mutex_lock(&msu_buffer_mutex); | |
256 | mbe = __msu_buffer_entry_find(mbuf->name); | |
257 | if (mbe) { | |
258 | list_del(&mbe->entry); | |
259 | kfree(mbe); | |
260 | } | |
261 | mutex_unlock(&msu_buffer_mutex); | |
262 | } | |
263 | EXPORT_SYMBOL_GPL(intel_th_msu_buffer_unregister); | |
264 | ||
ba82664c AS |
265 | static inline bool msc_block_is_empty(struct msc_block_desc *bdesc) |
266 | { | |
267 | /* header hasn't been written */ | |
268 | if (!bdesc->valid_dw) | |
269 | return true; | |
270 | ||
271 | /* valid_dw includes the header */ | |
272 | if (!msc_data_sz(bdesc)) | |
273 | return true; | |
274 | ||
275 | return false; | |
276 | } | |
277 | ||
57b69a1f | 278 | static inline struct scatterlist *msc_win_base_sg(struct msc_window *win) |
ba39bd83 | 279 | { |
57b69a1f | 280 | return win->sgt->sgl; |
ba39bd83 AS |
281 | } |
282 | ||
57b69a1f | 283 | static inline struct msc_block_desc *msc_win_base(struct msc_window *win) |
fa52b3fe | 284 | { |
57b69a1f | 285 | return sg_virt(msc_win_base_sg(win)); |
fa52b3fe AS |
286 | } |
287 | ||
57b69a1f | 288 | static inline dma_addr_t msc_win_base_dma(struct msc_window *win) |
ba39bd83 | 289 | { |
57b69a1f | 290 | return sg_dma_address(msc_win_base_sg(win)); |
ba39bd83 AS |
291 | } |
292 | ||
293 | static inline unsigned long | |
57b69a1f | 294 | msc_win_base_pfn(struct msc_window *win) |
ba39bd83 | 295 | { |
57b69a1f | 296 | return PFN_DOWN(msc_win_base_dma(win)); |
ba39bd83 AS |
297 | } |
298 | ||
aad14ad3 AS |
299 | /** |
300 | * msc_is_last_win() - check if a window is the last one for a given MSC | |
301 | * @win: window | |
302 | * Return: true if @win is the last window in MSC's multiblock buffer | |
303 | */ | |
304 | static inline bool msc_is_last_win(struct msc_window *win) | |
305 | { | |
306 | return win->entry.next == &win->msc->win_list; | |
307 | } | |
308 | ||
309 | /** | |
310 | * msc_next_window() - return next window in the multiblock buffer | |
311 | * @win: current window | |
312 | * | |
313 | * Return: window following the current one | |
314 | */ | |
315 | static struct msc_window *msc_next_window(struct msc_window *win) | |
316 | { | |
317 | if (msc_is_last_win(win)) | |
318 | return list_first_entry(&win->msc->win_list, struct msc_window, | |
319 | entry); | |
320 | ||
321 | return list_next_entry(win, entry); | |
322 | } | |
323 | ||
615c164d AS |
324 | static size_t msc_win_total_sz(struct msc_window *win) |
325 | { | |
57b69a1f | 326 | struct scatterlist *sg; |
615c164d AS |
327 | unsigned int blk; |
328 | size_t size = 0; | |
329 | ||
57b69a1f AS |
330 | for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { |
331 | struct msc_block_desc *bdesc = sg_virt(sg); | |
615c164d AS |
332 | |
333 | if (msc_block_wrapped(bdesc)) | |
8e3ef7b4 | 334 | return (size_t)win->nr_blocks << PAGE_SHIFT; |
615c164d AS |
335 | |
336 | size += msc_total_sz(bdesc); | |
337 | if (msc_block_last_written(bdesc)) | |
338 | break; | |
339 | } | |
340 | ||
341 | return size; | |
342 | } | |
343 | ||
ba82664c | 344 | /** |
f505e91e | 345 | * msc_find_window() - find a window matching a given sg_table |
ba82664c | 346 | * @msc: MSC device |
f505e91e AS |
347 | * @sgt: SG table of the window |
348 | * @nonempty: skip over empty windows | |
ba82664c | 349 | * |
f505e91e AS |
350 | * Return: MSC window structure pointer or NULL if the window |
351 | * could not be found. | |
ba82664c | 352 | */ |
f505e91e AS |
353 | static struct msc_window * |
354 | msc_find_window(struct msc *msc, struct sg_table *sgt, bool nonempty) | |
ba82664c | 355 | { |
f505e91e | 356 | struct msc_window *win; |
ba82664c AS |
357 | unsigned int found = 0; |
358 | ||
359 | if (list_empty(&msc->win_list)) | |
360 | return NULL; | |
361 | ||
362 | /* | |
363 | * we might need a radix tree for this, depending on how | |
364 | * many windows a typical user would allocate; ideally it's | |
365 | * something like 2, in which case we're good | |
366 | */ | |
367 | list_for_each_entry(win, &msc->win_list, entry) { | |
f505e91e | 368 | if (win->sgt == sgt) |
ba82664c AS |
369 | found++; |
370 | ||
371 | /* skip the empty ones */ | |
57b69a1f | 372 | if (nonempty && msc_block_is_empty(msc_win_base(win))) |
ba82664c AS |
373 | continue; |
374 | ||
375 | if (found) | |
376 | return win; | |
377 | } | |
378 | ||
f505e91e AS |
379 | return NULL; |
380 | } | |
381 | ||
382 | /** | |
383 | * msc_oldest_window() - locate the window with oldest data | |
384 | * @msc: MSC device | |
385 | * | |
386 | * This should only be used in multiblock mode. Caller should hold the | |
387 | * msc::user_count reference. | |
388 | * | |
389 | * Return: the oldest window with valid data | |
390 | */ | |
391 | static struct msc_window *msc_oldest_window(struct msc *msc) | |
392 | { | |
393 | struct msc_window *win; | |
394 | ||
395 | if (list_empty(&msc->win_list)) | |
396 | return NULL; | |
397 | ||
398 | win = msc_find_window(msc, msc_next_window(msc->cur_win)->sgt, true); | |
399 | if (win) | |
400 | return win; | |
401 | ||
0de9e035 | 402 | return list_first_entry(&msc->win_list, struct msc_window, entry); |
ba82664c AS |
403 | } |
404 | ||
405 | /** | |
57b69a1f | 406 | * msc_win_oldest_sg() - locate the oldest block in a given window |
ba82664c AS |
407 | * @win: window to look at |
408 | * | |
409 | * Return: index of the block with the oldest data | |
410 | */ | |
57b69a1f | 411 | static struct scatterlist *msc_win_oldest_sg(struct msc_window *win) |
ba82664c AS |
412 | { |
413 | unsigned int blk; | |
57b69a1f AS |
414 | struct scatterlist *sg; |
415 | struct msc_block_desc *bdesc = msc_win_base(win); | |
ba82664c AS |
416 | |
417 | /* without wrapping, first block is the oldest */ | |
418 | if (!msc_block_wrapped(bdesc)) | |
57b69a1f | 419 | return msc_win_base_sg(win); |
ba82664c AS |
420 | |
421 | /* | |
422 | * with wrapping, last written block contains both the newest and the | |
423 | * oldest data for this window. | |
424 | */ | |
57b69a1f AS |
425 | for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { |
426 | struct msc_block_desc *bdesc = sg_virt(sg); | |
ba82664c AS |
427 | |
428 | if (msc_block_last_written(bdesc)) | |
57b69a1f | 429 | return sg; |
ba82664c AS |
430 | } |
431 | ||
57b69a1f | 432 | return msc_win_base_sg(win); |
ba82664c AS |
433 | } |
434 | ||
ba82664c AS |
435 | static struct msc_block_desc *msc_iter_bdesc(struct msc_iter *iter) |
436 | { | |
57b69a1f | 437 | return sg_virt(iter->block); |
ba82664c AS |
438 | } |
439 | ||
440 | static struct msc_iter *msc_iter_install(struct msc *msc) | |
441 | { | |
442 | struct msc_iter *iter; | |
443 | ||
444 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
445 | if (!iter) | |
a45ff6ed AS |
446 | return ERR_PTR(-ENOMEM); |
447 | ||
448 | mutex_lock(&msc->buf_mutex); | |
449 | ||
450 | /* | |
451 | * Reading and tracing are mutually exclusive; if msc is | |
452 | * enabled, open() will fail; otherwise existing readers | |
453 | * will prevent enabling the msc and the rest of fops don't | |
454 | * need to worry about it. | |
455 | */ | |
456 | if (msc->enabled) { | |
457 | kfree(iter); | |
458 | iter = ERR_PTR(-EBUSY); | |
459 | goto unlock; | |
460 | } | |
ba82664c | 461 | |
ba82664c AS |
462 | iter->msc = msc; |
463 | ||
ba82664c | 464 | list_add_tail(&iter->entry, &msc->iter_list); |
a45ff6ed AS |
465 | unlock: |
466 | mutex_unlock(&msc->buf_mutex); | |
ba82664c AS |
467 | |
468 | return iter; | |
469 | } | |
470 | ||
471 | static void msc_iter_remove(struct msc_iter *iter, struct msc *msc) | |
472 | { | |
a45ff6ed | 473 | mutex_lock(&msc->buf_mutex); |
ba82664c | 474 | list_del(&iter->entry); |
a45ff6ed | 475 | mutex_unlock(&msc->buf_mutex); |
ba82664c AS |
476 | |
477 | kfree(iter); | |
478 | } | |
479 | ||
480 | static void msc_iter_block_start(struct msc_iter *iter) | |
481 | { | |
57b69a1f | 482 | if (iter->start_block) |
ba82664c AS |
483 | return; |
484 | ||
57b69a1f | 485 | iter->start_block = msc_win_oldest_sg(iter->win); |
ba82664c AS |
486 | iter->block = iter->start_block; |
487 | iter->wrap_count = 0; | |
488 | ||
489 | /* | |
490 | * start with the block with oldest data; if data has wrapped | |
491 | * in this window, it should be in this block | |
492 | */ | |
493 | if (msc_block_wrapped(msc_iter_bdesc(iter))) | |
494 | iter->wrap_count = 2; | |
495 | ||
496 | } | |
497 | ||
498 | static int msc_iter_win_start(struct msc_iter *iter, struct msc *msc) | |
499 | { | |
500 | /* already started, nothing to do */ | |
501 | if (iter->start_win) | |
502 | return 0; | |
503 | ||
504 | iter->start_win = msc_oldest_window(msc); | |
505 | if (!iter->start_win) | |
506 | return -EINVAL; | |
507 | ||
508 | iter->win = iter->start_win; | |
57b69a1f | 509 | iter->start_block = NULL; |
ba82664c AS |
510 | |
511 | msc_iter_block_start(iter); | |
512 | ||
513 | return 0; | |
514 | } | |
515 | ||
516 | static int msc_iter_win_advance(struct msc_iter *iter) | |
517 | { | |
518 | iter->win = msc_next_window(iter->win); | |
57b69a1f | 519 | iter->start_block = NULL; |
ba82664c AS |
520 | |
521 | if (iter->win == iter->start_win) { | |
522 | iter->eof++; | |
523 | return 1; | |
524 | } | |
525 | ||
526 | msc_iter_block_start(iter); | |
527 | ||
528 | return 0; | |
529 | } | |
530 | ||
531 | static int msc_iter_block_advance(struct msc_iter *iter) | |
532 | { | |
533 | iter->block_off = 0; | |
534 | ||
535 | /* wrapping */ | |
536 | if (iter->wrap_count && iter->block == iter->start_block) { | |
537 | iter->wrap_count--; | |
538 | if (!iter->wrap_count) | |
539 | /* copied newest data from the wrapped block */ | |
540 | return msc_iter_win_advance(iter); | |
541 | } | |
542 | ||
543 | /* no wrapping, check for last written block */ | |
544 | if (!iter->wrap_count && msc_block_last_written(msc_iter_bdesc(iter))) | |
545 | /* copied newest data for the window */ | |
546 | return msc_iter_win_advance(iter); | |
547 | ||
548 | /* block advance */ | |
57b69a1f AS |
549 | if (sg_is_last(iter->block)) |
550 | iter->block = msc_win_base_sg(iter->win); | |
551 | else | |
552 | iter->block = sg_next(iter->block); | |
ba82664c AS |
553 | |
554 | /* no wrapping, sanity check in case there is no last written block */ | |
555 | if (!iter->wrap_count && iter->block == iter->start_block) | |
556 | return msc_iter_win_advance(iter); | |
557 | ||
558 | return 0; | |
559 | } | |
560 | ||
561 | /** | |
562 | * msc_buffer_iterate() - go through multiblock buffer's data | |
563 | * @iter: iterator structure | |
564 | * @size: amount of data to scan | |
565 | * @data: callback's private data | |
566 | * @fn: iterator callback | |
567 | * | |
568 | * This will start at the window which will be written to next (containing | |
569 | * the oldest data) and work its way to the current window, calling @fn | |
570 | * for each chunk of data as it goes. | |
571 | * | |
572 | * Caller should have msc::user_count reference to make sure the buffer | |
573 | * doesn't disappear from under us. | |
574 | * | |
575 | * Return: amount of data actually scanned. | |
576 | */ | |
577 | static ssize_t | |
578 | msc_buffer_iterate(struct msc_iter *iter, size_t size, void *data, | |
579 | unsigned long (*fn)(void *, void *, size_t)) | |
580 | { | |
581 | struct msc *msc = iter->msc; | |
582 | size_t len = size; | |
583 | unsigned int advance; | |
584 | ||
585 | if (iter->eof) | |
586 | return 0; | |
587 | ||
588 | /* start with the oldest window */ | |
589 | if (msc_iter_win_start(iter, msc)) | |
590 | return 0; | |
591 | ||
592 | do { | |
593 | unsigned long data_bytes = msc_data_sz(msc_iter_bdesc(iter)); | |
594 | void *src = (void *)msc_iter_bdesc(iter) + MSC_BDESC; | |
595 | size_t tocopy = data_bytes, copied = 0; | |
596 | size_t remaining = 0; | |
597 | ||
598 | advance = 1; | |
599 | ||
600 | /* | |
601 | * If block wrapping happened, we need to visit the last block | |
602 | * twice, because it contains both the oldest and the newest | |
603 | * data in this window. | |
604 | * | |
605 | * First time (wrap_count==2), in the very beginning, to collect | |
606 | * the oldest data, which is in the range | |
607 | * (data_bytes..DATA_IN_PAGE). | |
608 | * | |
609 | * Second time (wrap_count==1), it's just like any other block, | |
610 | * containing data in the range of [MSC_BDESC..data_bytes]. | |
611 | */ | |
e4eca2a1 | 612 | if (iter->block == iter->start_block && iter->wrap_count == 2) { |
ba82664c AS |
613 | tocopy = DATA_IN_PAGE - data_bytes; |
614 | src += data_bytes; | |
615 | } | |
616 | ||
617 | if (!tocopy) | |
618 | goto next_block; | |
619 | ||
620 | tocopy -= iter->block_off; | |
621 | src += iter->block_off; | |
622 | ||
623 | if (len < tocopy) { | |
624 | tocopy = len; | |
625 | advance = 0; | |
626 | } | |
627 | ||
628 | remaining = fn(data, src, tocopy); | |
629 | ||
630 | if (remaining) | |
631 | advance = 0; | |
632 | ||
633 | copied = tocopy - remaining; | |
634 | len -= copied; | |
635 | iter->block_off += copied; | |
636 | iter->offset += copied; | |
637 | ||
638 | if (!advance) | |
639 | break; | |
640 | ||
641 | next_block: | |
642 | if (msc_iter_block_advance(iter)) | |
643 | break; | |
644 | ||
645 | } while (len); | |
646 | ||
647 | return size - len; | |
648 | } | |
649 | ||
650 | /** | |
651 | * msc_buffer_clear_hw_header() - clear hw header for multiblock | |
652 | * @msc: MSC device | |
653 | */ | |
654 | static void msc_buffer_clear_hw_header(struct msc *msc) | |
655 | { | |
656 | struct msc_window *win; | |
57b69a1f | 657 | struct scatterlist *sg; |
ba82664c | 658 | |
ba82664c AS |
659 | list_for_each_entry(win, &msc->win_list, entry) { |
660 | unsigned int blk; | |
ba82664c | 661 | |
57b69a1f AS |
662 | for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { |
663 | struct msc_block_desc *bdesc = sg_virt(sg); | |
ba82664c | 664 | |
9ed0a59c | 665 | memset_startat(bdesc, 0, hw_tag); |
ba82664c AS |
666 | } |
667 | } | |
ba82664c AS |
668 | } |
669 | ||
aac8da65 AS |
670 | static int intel_th_msu_init(struct msc *msc) |
671 | { | |
672 | u32 mintctl, msusts; | |
673 | ||
674 | if (!msc->do_irq) | |
675 | return 0; | |
676 | ||
615c164d AS |
677 | if (!msc->mbuf) |
678 | return 0; | |
679 | ||
aac8da65 AS |
680 | mintctl = ioread32(msc->msu_base + REG_MSU_MINTCTL); |
681 | mintctl |= msc->index ? M1BLIE : M0BLIE; | |
682 | iowrite32(mintctl, msc->msu_base + REG_MSU_MINTCTL); | |
683 | if (mintctl != ioread32(msc->msu_base + REG_MSU_MINTCTL)) { | |
684 | dev_info(msc_dev(msc), "MINTCTL ignores writes: no usable interrupts\n"); | |
685 | msc->do_irq = 0; | |
686 | return 0; | |
687 | } | |
688 | ||
689 | msusts = ioread32(msc->msu_base + REG_MSU_MSUSTS); | |
690 | iowrite32(msusts, msc->msu_base + REG_MSU_MSUSTS); | |
691 | ||
692 | return 0; | |
693 | } | |
694 | ||
695 | static void intel_th_msu_deinit(struct msc *msc) | |
696 | { | |
697 | u32 mintctl; | |
698 | ||
699 | if (!msc->do_irq) | |
700 | return; | |
701 | ||
702 | mintctl = ioread32(msc->msu_base + REG_MSU_MINTCTL); | |
703 | mintctl &= msc->index ? ~M1BLIE : ~M0BLIE; | |
704 | iowrite32(mintctl, msc->msu_base + REG_MSU_MINTCTL); | |
705 | } | |
706 | ||
615c164d AS |
707 | static int msc_win_set_lockout(struct msc_window *win, |
708 | enum lockout_state expect, | |
709 | enum lockout_state new) | |
710 | { | |
711 | enum lockout_state old; | |
712 | unsigned long flags; | |
713 | int ret = 0; | |
714 | ||
715 | if (!win->msc->mbuf) | |
716 | return 0; | |
717 | ||
718 | spin_lock_irqsave(&win->lo_lock, flags); | |
719 | old = win->lockout; | |
720 | ||
721 | if (old != expect) { | |
722 | ret = -EINVAL; | |
615c164d AS |
723 | goto unlock; |
724 | } | |
725 | ||
726 | win->lockout = new; | |
727 | ||
ed5207af AS |
728 | if (old == expect && new == WIN_LOCKED) |
729 | atomic_inc(&win->msc->user_count); | |
730 | else if (old == expect && old == WIN_LOCKED) | |
731 | atomic_dec(&win->msc->user_count); | |
732 | ||
615c164d AS |
733 | unlock: |
734 | spin_unlock_irqrestore(&win->lo_lock, flags); | |
735 | ||
736 | if (ret) { | |
737 | if (expect == WIN_READY && old == WIN_LOCKED) | |
738 | return -EBUSY; | |
739 | ||
740 | /* from intel_th_msc_window_unlock(), don't warn if not locked */ | |
741 | if (expect == WIN_LOCKED && old == new) | |
742 | return 0; | |
885f1235 AS |
743 | |
744 | dev_warn_ratelimited(msc_dev(win->msc), | |
745 | "expected lockout state %d, got %d\n", | |
746 | expect, old); | |
615c164d AS |
747 | } |
748 | ||
749 | return ret; | |
750 | } | |
ba82664c AS |
751 | /** |
752 | * msc_configure() - set up MSC hardware | |
753 | * @msc: the MSC device to configure | |
754 | * | |
755 | * Program storage mode, wrapping, burst length and trace buffer address | |
a45ff6ed AS |
756 | * into a given MSC. Then, enable tracing and set msc::enabled. |
757 | * The latter is serialized on msc::buf_mutex, so make sure to hold it. | |
76e9f438 RD |
758 | * |
759 | * Return: %0 for success or a negative error code otherwise. | |
ba82664c AS |
760 | */ |
761 | static int msc_configure(struct msc *msc) | |
762 | { | |
763 | u32 reg; | |
764 | ||
a45ff6ed AS |
765 | lockdep_assert_held(&msc->buf_mutex); |
766 | ||
ba82664c | 767 | if (msc->mode > MSC_MODE_MULTI) |
ce666be8 | 768 | return -EINVAL; |
ba82664c | 769 | |
615c164d AS |
770 | if (msc->mode == MSC_MODE_MULTI) { |
771 | if (msc_win_set_lockout(msc->cur_win, WIN_READY, WIN_INUSE)) | |
772 | return -EBUSY; | |
773 | ||
ba82664c | 774 | msc_buffer_clear_hw_header(msc); |
615c164d | 775 | } |
ba82664c | 776 | |
092f47c3 AS |
777 | msc->orig_addr = ioread32(msc->reg_base + REG_MSU_MSC0BAR); |
778 | msc->orig_sz = ioread32(msc->reg_base + REG_MSU_MSC0SIZE); | |
779 | ||
ba82664c AS |
780 | reg = msc->base_addr >> PAGE_SHIFT; |
781 | iowrite32(reg, msc->reg_base + REG_MSU_MSC0BAR); | |
782 | ||
783 | if (msc->mode == MSC_MODE_SINGLE) { | |
784 | reg = msc->nr_pages; | |
785 | iowrite32(reg, msc->reg_base + REG_MSU_MSC0SIZE); | |
786 | } | |
787 | ||
788 | reg = ioread32(msc->reg_base + REG_MSU_MSC0CTL); | |
789 | reg &= ~(MSC_MODE | MSC_WRAPEN | MSC_EN | MSC_RD_HDR_OVRD); | |
790 | ||
a45ff6ed | 791 | reg |= MSC_EN; |
ba82664c AS |
792 | reg |= msc->mode << __ffs(MSC_MODE); |
793 | reg |= msc->burst_len << __ffs(MSC_LEN); | |
a45ff6ed | 794 | |
ba82664c AS |
795 | if (msc->wrap) |
796 | reg |= MSC_WRAPEN; | |
ba82664c AS |
797 | |
798 | iowrite32(reg, msc->reg_base + REG_MSU_MSC0CTL); | |
799 | ||
615c164d AS |
800 | intel_th_msu_init(msc); |
801 | ||
a45ff6ed AS |
802 | msc->thdev->output.multiblock = msc->mode == MSC_MODE_MULTI; |
803 | intel_th_trace_enable(msc->thdev); | |
804 | msc->enabled = 1; | |
805 | ||
615c164d AS |
806 | if (msc->mbuf && msc->mbuf->activate) |
807 | msc->mbuf->activate(msc->mbuf_priv); | |
ba82664c AS |
808 | |
809 | return 0; | |
810 | } | |
811 | ||
812 | /** | |
813 | * msc_disable() - disable MSC hardware | |
814 | * @msc: MSC device to disable | |
815 | * | |
816 | * If @msc is enabled, disable tracing on the switch and then disable MSC | |
a45ff6ed | 817 | * storage. Caller must hold msc::buf_mutex. |
ba82664c AS |
818 | */ |
819 | static void msc_disable(struct msc *msc) | |
820 | { | |
615c164d | 821 | struct msc_window *win = msc->cur_win; |
ba82664c AS |
822 | u32 reg; |
823 | ||
a45ff6ed | 824 | lockdep_assert_held(&msc->buf_mutex); |
ba82664c | 825 | |
615c164d AS |
826 | if (msc->mode == MSC_MODE_MULTI) |
827 | msc_win_set_lockout(win, WIN_INUSE, WIN_LOCKED); | |
828 | ||
829 | if (msc->mbuf && msc->mbuf->deactivate) | |
830 | msc->mbuf->deactivate(msc->mbuf_priv); | |
831 | intel_th_msu_deinit(msc); | |
ba82664c AS |
832 | intel_th_trace_disable(msc->thdev); |
833 | ||
ba82664c | 834 | if (msc->mode == MSC_MODE_SINGLE) { |
8d415512 | 835 | reg = ioread32(msc->reg_base + REG_MSU_MSC0STS); |
ba82664c AS |
836 | msc->single_wrap = !!(reg & MSCSTS_WRAPSTAT); |
837 | ||
838 | reg = ioread32(msc->reg_base + REG_MSU_MSC0MWP); | |
839 | msc->single_sz = reg & ((msc->nr_pages << PAGE_SHIFT) - 1); | |
840 | dev_dbg(msc_dev(msc), "MSCnMWP: %08x/%08lx, wrap: %d\n", | |
841 | reg, msc->single_sz, msc->single_wrap); | |
842 | } | |
843 | ||
844 | reg = ioread32(msc->reg_base + REG_MSU_MSC0CTL); | |
845 | reg &= ~MSC_EN; | |
846 | iowrite32(reg, msc->reg_base + REG_MSU_MSC0CTL); | |
615c164d AS |
847 | |
848 | if (msc->mbuf && msc->mbuf->ready) | |
849 | msc->mbuf->ready(msc->mbuf_priv, win->sgt, | |
850 | msc_win_total_sz(win)); | |
851 | ||
ba82664c AS |
852 | msc->enabled = 0; |
853 | ||
092f47c3 AS |
854 | iowrite32(msc->orig_addr, msc->reg_base + REG_MSU_MSC0BAR); |
855 | iowrite32(msc->orig_sz, msc->reg_base + REG_MSU_MSC0SIZE); | |
ba82664c AS |
856 | |
857 | dev_dbg(msc_dev(msc), "MSCnNWSA: %08x\n", | |
858 | ioread32(msc->reg_base + REG_MSU_MSC0NWSA)); | |
859 | ||
860 | reg = ioread32(msc->reg_base + REG_MSU_MSC0STS); | |
861 | dev_dbg(msc_dev(msc), "MSCnSTS: %08x\n", reg); | |
615c164d AS |
862 | |
863 | reg = ioread32(msc->reg_base + REG_MSU_MSUSTS); | |
864 | reg &= msc->index ? MSUSTS_MSC1BLAST : MSUSTS_MSC0BLAST; | |
865 | iowrite32(reg, msc->reg_base + REG_MSU_MSUSTS); | |
ba82664c AS |
866 | } |
867 | ||
868 | static int intel_th_msc_activate(struct intel_th_device *thdev) | |
869 | { | |
870 | struct msc *msc = dev_get_drvdata(&thdev->dev); | |
a45ff6ed | 871 | int ret = -EBUSY; |
ba82664c AS |
872 | |
873 | if (!atomic_inc_unless_negative(&msc->user_count)) | |
874 | return -ENODEV; | |
875 | ||
a45ff6ed | 876 | mutex_lock(&msc->buf_mutex); |
ba82664c | 877 | |
a45ff6ed AS |
878 | /* if there are readers, refuse */ |
879 | if (list_empty(&msc->iter_list)) | |
880 | ret = msc_configure(msc); | |
ba82664c | 881 | |
a45ff6ed AS |
882 | mutex_unlock(&msc->buf_mutex); |
883 | ||
884 | if (ret) | |
885 | atomic_dec(&msc->user_count); | |
ba82664c | 886 | |
a45ff6ed | 887 | return ret; |
ba82664c AS |
888 | } |
889 | ||
890 | static void intel_th_msc_deactivate(struct intel_th_device *thdev) | |
891 | { | |
892 | struct msc *msc = dev_get_drvdata(&thdev->dev); | |
893 | ||
a45ff6ed AS |
894 | mutex_lock(&msc->buf_mutex); |
895 | if (msc->enabled) { | |
896 | msc_disable(msc); | |
897 | atomic_dec(&msc->user_count); | |
898 | } | |
899 | mutex_unlock(&msc->buf_mutex); | |
ba82664c AS |
900 | } |
901 | ||
902 | /** | |
903 | * msc_buffer_contig_alloc() - allocate a contiguous buffer for SINGLE mode | |
904 | * @msc: MSC device | |
905 | * @size: allocation size in bytes | |
906 | * | |
907 | * This modifies msc::base, which requires msc::buf_mutex to serialize, so the | |
908 | * caller is expected to hold it. | |
909 | * | |
910 | * Return: 0 on success, -errno otherwise. | |
911 | */ | |
912 | static int msc_buffer_contig_alloc(struct msc *msc, unsigned long size) | |
913 | { | |
4e0eaf23 | 914 | unsigned long nr_pages = size >> PAGE_SHIFT; |
ba82664c AS |
915 | unsigned int order = get_order(size); |
916 | struct page *page; | |
4e0eaf23 | 917 | int ret; |
ba82664c AS |
918 | |
919 | if (!size) | |
920 | return 0; | |
921 | ||
4e0eaf23 AS |
922 | ret = sg_alloc_table(&msc->single_sgt, 1, GFP_KERNEL); |
923 | if (ret) | |
924 | goto err_out; | |
925 | ||
926 | ret = -ENOMEM; | |
918b8646 | 927 | page = alloc_pages(GFP_KERNEL | __GFP_ZERO | GFP_DMA32, order); |
ba82664c | 928 | if (!page) |
4e0eaf23 | 929 | goto err_free_sgt; |
ba82664c AS |
930 | |
931 | split_page(page, order); | |
4e0eaf23 AS |
932 | sg_set_buf(msc->single_sgt.sgl, page_address(page), size); |
933 | ||
934 | ret = dma_map_sg(msc_dev(msc)->parent->parent, msc->single_sgt.sgl, 1, | |
935 | DMA_FROM_DEVICE); | |
936 | if (ret < 0) | |
937 | goto err_free_pages; | |
938 | ||
939 | msc->nr_pages = nr_pages; | |
ba82664c | 940 | msc->base = page_address(page); |
4e0eaf23 | 941 | msc->base_addr = sg_dma_address(msc->single_sgt.sgl); |
ba82664c AS |
942 | |
943 | return 0; | |
4e0eaf23 AS |
944 | |
945 | err_free_pages: | |
946 | __free_pages(page, order); | |
947 | ||
948 | err_free_sgt: | |
949 | sg_free_table(&msc->single_sgt); | |
950 | ||
951 | err_out: | |
952 | return ret; | |
ba82664c AS |
953 | } |
954 | ||
955 | /** | |
956 | * msc_buffer_contig_free() - free a contiguous buffer | |
957 | * @msc: MSC configured in SINGLE mode | |
958 | */ | |
959 | static void msc_buffer_contig_free(struct msc *msc) | |
960 | { | |
961 | unsigned long off; | |
962 | ||
4e0eaf23 AS |
963 | dma_unmap_sg(msc_dev(msc)->parent->parent, msc->single_sgt.sgl, |
964 | 1, DMA_FROM_DEVICE); | |
965 | sg_free_table(&msc->single_sgt); | |
966 | ||
ba82664c AS |
967 | for (off = 0; off < msc->nr_pages << PAGE_SHIFT; off += PAGE_SIZE) { |
968 | struct page *page = virt_to_page(msc->base + off); | |
969 | ||
970 | page->mapping = NULL; | |
971 | __free_page(page); | |
972 | } | |
973 | ||
974 | msc->nr_pages = 0; | |
975 | } | |
976 | ||
977 | /** | |
978 | * msc_buffer_contig_get_page() - find a page at a given offset | |
979 | * @msc: MSC configured in SINGLE mode | |
980 | * @pgoff: page offset | |
981 | * | |
982 | * Return: page, if @pgoff is within the range, NULL otherwise. | |
983 | */ | |
984 | static struct page *msc_buffer_contig_get_page(struct msc *msc, | |
985 | unsigned long pgoff) | |
986 | { | |
987 | if (pgoff >= msc->nr_pages) | |
988 | return NULL; | |
989 | ||
990 | return virt_to_page(msc->base + (pgoff << PAGE_SHIFT)); | |
991 | } | |
992 | ||
ba39bd83 | 993 | static int __msc_buffer_win_alloc(struct msc_window *win, |
fa52b3fe | 994 | unsigned int nr_segs) |
ba39bd83 AS |
995 | { |
996 | struct scatterlist *sg_ptr; | |
997 | void *block; | |
998 | int i, ret; | |
999 | ||
bbbc08a1 | 1000 | ret = sg_alloc_table(win->sgt, nr_segs, GFP_KERNEL); |
ba39bd83 AS |
1001 | if (ret) |
1002 | return -ENOMEM; | |
1003 | ||
bbbc08a1 | 1004 | for_each_sg(win->sgt->sgl, sg_ptr, nr_segs, i) { |
ba39bd83 AS |
1005 | block = dma_alloc_coherent(msc_dev(win->msc)->parent->parent, |
1006 | PAGE_SIZE, &sg_dma_address(sg_ptr), | |
1007 | GFP_KERNEL); | |
1008 | if (!block) | |
1009 | goto err_nomem; | |
1010 | ||
1011 | sg_set_buf(sg_ptr, block, PAGE_SIZE); | |
1012 | } | |
1013 | ||
fa52b3fe | 1014 | return nr_segs; |
ba39bd83 AS |
1015 | |
1016 | err_nomem: | |
57b69a1f | 1017 | for_each_sg(win->sgt->sgl, sg_ptr, i, ret) |
ba39bd83 | 1018 | dma_free_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE, |
57b69a1f | 1019 | sg_virt(sg_ptr), sg_dma_address(sg_ptr)); |
ba39bd83 | 1020 | |
bbbc08a1 | 1021 | sg_free_table(win->sgt); |
ba39bd83 AS |
1022 | |
1023 | return -ENOMEM; | |
1024 | } | |
1025 | ||
b96fb368 | 1026 | #ifdef CONFIG_X86 |
02ca71ef | 1027 | static void msc_buffer_set_uc(struct msc *msc) |
b96fb368 | 1028 | { |
57b69a1f | 1029 | struct scatterlist *sg_ptr; |
02ca71ef | 1030 | struct msc_window *win; |
b96fb368 SZ |
1031 | int i; |
1032 | ||
02ca71ef AS |
1033 | if (msc->mode == MSC_MODE_SINGLE) { |
1034 | set_memory_uc((unsigned long)msc->base, msc->nr_pages); | |
1035 | return; | |
1036 | } | |
1037 | ||
1038 | list_for_each_entry(win, &msc->win_list, entry) { | |
1039 | for_each_sg(win->sgt->sgl, sg_ptr, win->nr_segs, i) { | |
1040 | /* Set the page as uncached */ | |
1041 | set_memory_uc((unsigned long)sg_virt(sg_ptr), | |
1042 | PFN_DOWN(sg_ptr->length)); | |
1043 | } | |
57b69a1f | 1044 | } |
b96fb368 SZ |
1045 | } |
1046 | ||
02ca71ef | 1047 | static void msc_buffer_set_wb(struct msc *msc) |
b96fb368 | 1048 | { |
57b69a1f | 1049 | struct scatterlist *sg_ptr; |
02ca71ef | 1050 | struct msc_window *win; |
b96fb368 SZ |
1051 | int i; |
1052 | ||
02ca71ef AS |
1053 | if (msc->mode == MSC_MODE_SINGLE) { |
1054 | set_memory_wb((unsigned long)msc->base, msc->nr_pages); | |
1055 | return; | |
1056 | } | |
1057 | ||
1058 | list_for_each_entry(win, &msc->win_list, entry) { | |
1059 | for_each_sg(win->sgt->sgl, sg_ptr, win->nr_segs, i) { | |
1060 | /* Reset the page to write-back */ | |
1061 | set_memory_wb((unsigned long)sg_virt(sg_ptr), | |
1062 | PFN_DOWN(sg_ptr->length)); | |
1063 | } | |
57b69a1f | 1064 | } |
b96fb368 SZ |
1065 | } |
1066 | #else /* !X86 */ | |
1067 | static inline void | |
02ca71ef AS |
1068 | msc_buffer_set_uc(struct msc *msc) {} |
1069 | static inline void msc_buffer_set_wb(struct msc *msc) {} | |
b96fb368 SZ |
1070 | #endif /* CONFIG_X86 */ |
1071 | ||
ac12ad3c AS |
1072 | static struct page *msc_sg_page(struct scatterlist *sg) |
1073 | { | |
1074 | void *addr = sg_virt(sg); | |
1075 | ||
1076 | if (is_vmalloc_addr(addr)) | |
1077 | return vmalloc_to_page(addr); | |
1078 | ||
1079 | return sg_page(sg); | |
1080 | } | |
1081 | ||
ba82664c AS |
1082 | /** |
1083 | * msc_buffer_win_alloc() - alloc a window for a multiblock mode | |
1084 | * @msc: MSC device | |
1085 | * @nr_blocks: number of pages in this window | |
1086 | * | |
1087 | * This modifies msc::win_list and msc::base, which requires msc::buf_mutex | |
1088 | * to serialize, so the caller is expected to hold it. | |
1089 | * | |
1090 | * Return: 0 on success, -errno otherwise. | |
1091 | */ | |
1092 | static int msc_buffer_win_alloc(struct msc *msc, unsigned int nr_blocks) | |
1093 | { | |
1094 | struct msc_window *win; | |
b96fb368 | 1095 | int ret = -ENOMEM; |
ba82664c AS |
1096 | |
1097 | if (!nr_blocks) | |
1098 | return 0; | |
1099 | ||
ba39bd83 | 1100 | win = kzalloc(sizeof(*win), GFP_KERNEL); |
ba82664c AS |
1101 | if (!win) |
1102 | return -ENOMEM; | |
1103 | ||
ba39bd83 | 1104 | win->msc = msc; |
bbbc08a1 | 1105 | win->sgt = &win->_sgt; |
615c164d AS |
1106 | win->lockout = WIN_READY; |
1107 | spin_lock_init(&win->lo_lock); | |
ba39bd83 | 1108 | |
ba82664c | 1109 | if (!list_empty(&msc->win_list)) { |
0de9e035 AS |
1110 | struct msc_window *prev = list_last_entry(&msc->win_list, |
1111 | struct msc_window, | |
1112 | entry); | |
ba82664c AS |
1113 | |
1114 | win->pgoff = prev->pgoff + prev->nr_blocks; | |
1115 | } | |
1116 | ||
615c164d AS |
1117 | if (msc->mbuf && msc->mbuf->alloc_window) |
1118 | ret = msc->mbuf->alloc_window(msc->mbuf_priv, &win->sgt, | |
1119 | nr_blocks << PAGE_SHIFT); | |
1120 | else | |
1121 | ret = __msc_buffer_win_alloc(win, nr_blocks); | |
1122 | ||
1123 | if (ret <= 0) | |
ba39bd83 | 1124 | goto err_nomem; |
ba82664c | 1125 | |
fa52b3fe AS |
1126 | win->nr_segs = ret; |
1127 | win->nr_blocks = nr_blocks; | |
ba82664c AS |
1128 | |
1129 | if (list_empty(&msc->win_list)) { | |
57b69a1f AS |
1130 | msc->base = msc_win_base(win); |
1131 | msc->base_addr = msc_win_base_dma(win); | |
aad14ad3 | 1132 | msc->cur_win = win; |
ba82664c AS |
1133 | } |
1134 | ||
1135 | list_add_tail(&win->entry, &msc->win_list); | |
1136 | msc->nr_pages += nr_blocks; | |
1137 | ||
1138 | return 0; | |
1139 | ||
1140 | err_nomem: | |
ba82664c AS |
1141 | kfree(win); |
1142 | ||
1143 | return ret; | |
1144 | } | |
1145 | ||
ba39bd83 AS |
1146 | static void __msc_buffer_win_free(struct msc *msc, struct msc_window *win) |
1147 | { | |
57b69a1f | 1148 | struct scatterlist *sg; |
ba39bd83 AS |
1149 | int i; |
1150 | ||
57b69a1f | 1151 | for_each_sg(win->sgt->sgl, sg, win->nr_segs, i) { |
ac12ad3c | 1152 | struct page *page = msc_sg_page(sg); |
ba39bd83 AS |
1153 | |
1154 | page->mapping = NULL; | |
1155 | dma_free_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE, | |
57b69a1f | 1156 | sg_virt(sg), sg_dma_address(sg)); |
ba39bd83 | 1157 | } |
bbbc08a1 | 1158 | sg_free_table(win->sgt); |
ba39bd83 AS |
1159 | } |
1160 | ||
ba82664c AS |
1161 | /** |
1162 | * msc_buffer_win_free() - free a window from MSC's window list | |
1163 | * @msc: MSC device | |
1164 | * @win: window to free | |
1165 | * | |
1166 | * This modifies msc::win_list and msc::base, which requires msc::buf_mutex | |
1167 | * to serialize, so the caller is expected to hold it. | |
1168 | */ | |
1169 | static void msc_buffer_win_free(struct msc *msc, struct msc_window *win) | |
1170 | { | |
ba82664c AS |
1171 | msc->nr_pages -= win->nr_blocks; |
1172 | ||
1173 | list_del(&win->entry); | |
1174 | if (list_empty(&msc->win_list)) { | |
1175 | msc->base = NULL; | |
1176 | msc->base_addr = 0; | |
1177 | } | |
1178 | ||
615c164d AS |
1179 | if (msc->mbuf && msc->mbuf->free_window) |
1180 | msc->mbuf->free_window(msc->mbuf_priv, win->sgt); | |
1181 | else | |
1182 | __msc_buffer_win_free(msc, win); | |
ba82664c AS |
1183 | |
1184 | kfree(win); | |
1185 | } | |
1186 | ||
1187 | /** | |
1188 | * msc_buffer_relink() - set up block descriptors for multiblock mode | |
1189 | * @msc: MSC device | |
1190 | * | |
1191 | * This traverses msc::win_list, which requires msc::buf_mutex to serialize, | |
1192 | * so the caller is expected to hold it. | |
1193 | */ | |
1194 | static void msc_buffer_relink(struct msc *msc) | |
1195 | { | |
1196 | struct msc_window *win, *next_win; | |
1197 | ||
1198 | /* call with msc::mutex locked */ | |
1199 | list_for_each_entry(win, &msc->win_list, entry) { | |
57b69a1f | 1200 | struct scatterlist *sg; |
ba82664c AS |
1201 | unsigned int blk; |
1202 | u32 sw_tag = 0; | |
1203 | ||
1204 | /* | |
1205 | * Last window's next_win should point to the first window | |
1206 | * and MSC_SW_TAG_LASTWIN should be set. | |
1207 | */ | |
1208 | if (msc_is_last_win(win)) { | |
1209 | sw_tag |= MSC_SW_TAG_LASTWIN; | |
0de9e035 AS |
1210 | next_win = list_first_entry(&msc->win_list, |
1211 | struct msc_window, entry); | |
ba82664c | 1212 | } else { |
0de9e035 | 1213 | next_win = list_next_entry(win, entry); |
ba82664c AS |
1214 | } |
1215 | ||
57b69a1f AS |
1216 | for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { |
1217 | struct msc_block_desc *bdesc = sg_virt(sg); | |
ba82664c AS |
1218 | |
1219 | memset(bdesc, 0, sizeof(*bdesc)); | |
1220 | ||
57b69a1f | 1221 | bdesc->next_win = msc_win_base_pfn(next_win); |
ba82664c AS |
1222 | |
1223 | /* | |
1224 | * Similarly to last window, last block should point | |
1225 | * to the first one. | |
1226 | */ | |
fa52b3fe | 1227 | if (blk == win->nr_segs - 1) { |
ba82664c | 1228 | sw_tag |= MSC_SW_TAG_LASTBLK; |
57b69a1f | 1229 | bdesc->next_blk = msc_win_base_pfn(win); |
ba82664c | 1230 | } else { |
57b69a1f AS |
1231 | dma_addr_t addr = sg_dma_address(sg_next(sg)); |
1232 | ||
1233 | bdesc->next_blk = PFN_DOWN(addr); | |
ba82664c AS |
1234 | } |
1235 | ||
1236 | bdesc->sw_tag = sw_tag; | |
57b69a1f | 1237 | bdesc->block_sz = sg->length / 64; |
ba82664c AS |
1238 | } |
1239 | } | |
1240 | ||
1241 | /* | |
1242 | * Make the above writes globally visible before tracing is | |
1243 | * enabled to make sure hardware sees them coherently. | |
1244 | */ | |
1245 | wmb(); | |
1246 | } | |
1247 | ||
1248 | static void msc_buffer_multi_free(struct msc *msc) | |
1249 | { | |
1250 | struct msc_window *win, *iter; | |
1251 | ||
1252 | list_for_each_entry_safe(win, iter, &msc->win_list, entry) | |
1253 | msc_buffer_win_free(msc, win); | |
1254 | } | |
1255 | ||
1256 | static int msc_buffer_multi_alloc(struct msc *msc, unsigned long *nr_pages, | |
1257 | unsigned int nr_wins) | |
1258 | { | |
1259 | int ret, i; | |
1260 | ||
1261 | for (i = 0; i < nr_wins; i++) { | |
1262 | ret = msc_buffer_win_alloc(msc, nr_pages[i]); | |
1263 | if (ret) { | |
1264 | msc_buffer_multi_free(msc); | |
1265 | return ret; | |
1266 | } | |
1267 | } | |
1268 | ||
1269 | msc_buffer_relink(msc); | |
1270 | ||
1271 | return 0; | |
1272 | } | |
1273 | ||
1274 | /** | |
1275 | * msc_buffer_free() - free buffers for MSC | |
1276 | * @msc: MSC device | |
1277 | * | |
1278 | * Free MSC's storage buffers. | |
1279 | * | |
1280 | * This modifies msc::win_list and msc::base, which requires msc::buf_mutex to | |
1281 | * serialize, so the caller is expected to hold it. | |
1282 | */ | |
1283 | static void msc_buffer_free(struct msc *msc) | |
1284 | { | |
02ca71ef AS |
1285 | msc_buffer_set_wb(msc); |
1286 | ||
ba82664c AS |
1287 | if (msc->mode == MSC_MODE_SINGLE) |
1288 | msc_buffer_contig_free(msc); | |
1289 | else if (msc->mode == MSC_MODE_MULTI) | |
1290 | msc_buffer_multi_free(msc); | |
1291 | } | |
1292 | ||
1293 | /** | |
1294 | * msc_buffer_alloc() - allocate a buffer for MSC | |
1295 | * @msc: MSC device | |
76e9f438 RD |
1296 | * @nr_pages: number of pages for each window |
1297 | * @nr_wins: number of windows | |
ba82664c AS |
1298 | * |
1299 | * Allocate a storage buffer for MSC, depending on the msc::mode, it will be | |
1300 | * either done via msc_buffer_contig_alloc() for SINGLE operation mode or | |
1301 | * msc_buffer_win_alloc() for multiblock operation. The latter allocates one | |
1302 | * window per invocation, so in multiblock mode this can be called multiple | |
1303 | * times for the same MSC to allocate multiple windows. | |
1304 | * | |
1305 | * This modifies msc::win_list and msc::base, which requires msc::buf_mutex | |
1306 | * to serialize, so the caller is expected to hold it. | |
1307 | * | |
1308 | * Return: 0 on success, -errno otherwise. | |
1309 | */ | |
1310 | static int msc_buffer_alloc(struct msc *msc, unsigned long *nr_pages, | |
1311 | unsigned int nr_wins) | |
1312 | { | |
1313 | int ret; | |
1314 | ||
1315 | /* -1: buffer not allocated */ | |
1316 | if (atomic_read(&msc->user_count) != -1) | |
1317 | return -EBUSY; | |
1318 | ||
1319 | if (msc->mode == MSC_MODE_SINGLE) { | |
1320 | if (nr_wins != 1) | |
1321 | return -EINVAL; | |
1322 | ||
1323 | ret = msc_buffer_contig_alloc(msc, nr_pages[0] << PAGE_SHIFT); | |
1324 | } else if (msc->mode == MSC_MODE_MULTI) { | |
1325 | ret = msc_buffer_multi_alloc(msc, nr_pages, nr_wins); | |
1326 | } else { | |
ce666be8 | 1327 | ret = -EINVAL; |
ba82664c AS |
1328 | } |
1329 | ||
1330 | if (!ret) { | |
02ca71ef AS |
1331 | msc_buffer_set_uc(msc); |
1332 | ||
ba82664c AS |
1333 | /* allocation should be visible before the counter goes to 0 */ |
1334 | smp_mb__before_atomic(); | |
1335 | ||
1336 | if (WARN_ON_ONCE(atomic_cmpxchg(&msc->user_count, -1, 0) != -1)) | |
1337 | return -EINVAL; | |
1338 | } | |
1339 | ||
1340 | return ret; | |
1341 | } | |
1342 | ||
1343 | /** | |
1344 | * msc_buffer_unlocked_free_unless_used() - free a buffer unless it's in use | |
1345 | * @msc: MSC device | |
1346 | * | |
1347 | * This will free MSC buffer unless it is in use or there is no allocated | |
1348 | * buffer. | |
1349 | * Caller needs to hold msc::buf_mutex. | |
1350 | * | |
1351 | * Return: 0 on successful deallocation or if there was no buffer to | |
1352 | * deallocate, -EBUSY if there are active users. | |
1353 | */ | |
1354 | static int msc_buffer_unlocked_free_unless_used(struct msc *msc) | |
1355 | { | |
1356 | int count, ret = 0; | |
1357 | ||
1358 | count = atomic_cmpxchg(&msc->user_count, 0, -1); | |
1359 | ||
1360 | /* > 0: buffer is allocated and has users */ | |
1361 | if (count > 0) | |
1362 | ret = -EBUSY; | |
1363 | /* 0: buffer is allocated, no users */ | |
1364 | else if (!count) | |
1365 | msc_buffer_free(msc); | |
1366 | /* < 0: no buffer, nothing to do */ | |
1367 | ||
1368 | return ret; | |
1369 | } | |
1370 | ||
1371 | /** | |
1372 | * msc_buffer_free_unless_used() - free a buffer unless it's in use | |
1373 | * @msc: MSC device | |
1374 | * | |
1375 | * This is a locked version of msc_buffer_unlocked_free_unless_used(). | |
76e9f438 RD |
1376 | * |
1377 | * Return: 0 on successful deallocation or if there was no buffer to | |
1378 | * deallocate, -EBUSY if there are active users. | |
ba82664c AS |
1379 | */ |
1380 | static int msc_buffer_free_unless_used(struct msc *msc) | |
1381 | { | |
1382 | int ret; | |
1383 | ||
1384 | mutex_lock(&msc->buf_mutex); | |
1385 | ret = msc_buffer_unlocked_free_unless_used(msc); | |
1386 | mutex_unlock(&msc->buf_mutex); | |
1387 | ||
1388 | return ret; | |
1389 | } | |
1390 | ||
1391 | /** | |
1392 | * msc_buffer_get_page() - get MSC buffer page at a given offset | |
1393 | * @msc: MSC device | |
1394 | * @pgoff: page offset into the storage buffer | |
1395 | * | |
1396 | * This traverses msc::win_list, so holding msc::buf_mutex is expected from | |
1397 | * the caller. | |
1398 | * | |
1399 | * Return: page if @pgoff corresponds to a valid buffer page or NULL. | |
1400 | */ | |
1401 | static struct page *msc_buffer_get_page(struct msc *msc, unsigned long pgoff) | |
1402 | { | |
1403 | struct msc_window *win; | |
57b69a1f | 1404 | struct scatterlist *sg; |
fa52b3fe | 1405 | unsigned int blk; |
ba82664c AS |
1406 | |
1407 | if (msc->mode == MSC_MODE_SINGLE) | |
1408 | return msc_buffer_contig_get_page(msc, pgoff); | |
1409 | ||
1410 | list_for_each_entry(win, &msc->win_list, entry) | |
1411 | if (pgoff >= win->pgoff && pgoff < win->pgoff + win->nr_blocks) | |
1412 | goto found; | |
1413 | ||
1414 | return NULL; | |
1415 | ||
1416 | found: | |
1417 | pgoff -= win->pgoff; | |
fa52b3fe | 1418 | |
57b69a1f | 1419 | for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { |
ac12ad3c | 1420 | struct page *page = msc_sg_page(sg); |
57b69a1f | 1421 | size_t pgsz = PFN_DOWN(sg->length); |
fa52b3fe AS |
1422 | |
1423 | if (pgoff < pgsz) | |
1424 | return page + pgoff; | |
1425 | ||
1426 | pgoff -= pgsz; | |
1427 | } | |
1428 | ||
1429 | return NULL; | |
ba82664c AS |
1430 | } |
1431 | ||
1432 | /** | |
1433 | * struct msc_win_to_user_struct - data for copy_to_user() callback | |
1434 | * @buf: userspace buffer to copy data to | |
1435 | * @offset: running offset | |
1436 | */ | |
1437 | struct msc_win_to_user_struct { | |
1438 | char __user *buf; | |
1439 | unsigned long offset; | |
1440 | }; | |
1441 | ||
1442 | /** | |
1443 | * msc_win_to_user() - iterator for msc_buffer_iterate() to copy data to user | |
1444 | * @data: callback's private data | |
1445 | * @src: source buffer | |
1446 | * @len: amount of data to copy from the source buffer | |
76e9f438 RD |
1447 | * |
1448 | * Return: >= %0 for success or -errno for error. | |
ba82664c AS |
1449 | */ |
1450 | static unsigned long msc_win_to_user(void *data, void *src, size_t len) | |
1451 | { | |
1452 | struct msc_win_to_user_struct *u = data; | |
1453 | unsigned long ret; | |
1454 | ||
1455 | ret = copy_to_user(u->buf + u->offset, src, len); | |
1456 | u->offset += len - ret; | |
1457 | ||
1458 | return ret; | |
1459 | } | |
1460 | ||
1461 | ||
1462 | /* | |
1463 | * file operations' callbacks | |
1464 | */ | |
1465 | ||
1466 | static int intel_th_msc_open(struct inode *inode, struct file *file) | |
1467 | { | |
1468 | struct intel_th_device *thdev = file->private_data; | |
1469 | struct msc *msc = dev_get_drvdata(&thdev->dev); | |
1470 | struct msc_iter *iter; | |
1471 | ||
1472 | if (!capable(CAP_SYS_RAWIO)) | |
1473 | return -EPERM; | |
1474 | ||
1475 | iter = msc_iter_install(msc); | |
a45ff6ed AS |
1476 | if (IS_ERR(iter)) |
1477 | return PTR_ERR(iter); | |
ba82664c AS |
1478 | |
1479 | file->private_data = iter; | |
1480 | ||
1481 | return nonseekable_open(inode, file); | |
1482 | } | |
1483 | ||
1484 | static int intel_th_msc_release(struct inode *inode, struct file *file) | |
1485 | { | |
1486 | struct msc_iter *iter = file->private_data; | |
1487 | struct msc *msc = iter->msc; | |
1488 | ||
1489 | msc_iter_remove(iter, msc); | |
1490 | ||
1491 | return 0; | |
1492 | } | |
1493 | ||
1494 | static ssize_t | |
1495 | msc_single_to_user(struct msc *msc, char __user *buf, loff_t off, size_t len) | |
1496 | { | |
ed392688 | 1497 | unsigned long size = msc->nr_pages << PAGE_SHIFT, rem = len; |
ba82664c AS |
1498 | unsigned long start = off, tocopy = 0; |
1499 | ||
1500 | if (msc->single_wrap) { | |
1501 | start += msc->single_sz; | |
1502 | if (start < size) { | |
1503 | tocopy = min(rem, size - start); | |
1504 | if (copy_to_user(buf, msc->base + start, tocopy)) | |
1505 | return -EFAULT; | |
1506 | ||
1507 | buf += tocopy; | |
1508 | rem -= tocopy; | |
1509 | start += tocopy; | |
1510 | } | |
1511 | ||
1512 | start &= size - 1; | |
1513 | if (rem) { | |
1514 | tocopy = min(rem, msc->single_sz - start); | |
1515 | if (copy_to_user(buf, msc->base + start, tocopy)) | |
1516 | return -EFAULT; | |
1517 | ||
1518 | rem -= tocopy; | |
1519 | } | |
1520 | ||
1521 | return len - rem; | |
1522 | } | |
1523 | ||
1524 | if (copy_to_user(buf, msc->base + start, rem)) | |
1525 | return -EFAULT; | |
1526 | ||
1527 | return len; | |
1528 | } | |
1529 | ||
1530 | static ssize_t intel_th_msc_read(struct file *file, char __user *buf, | |
1531 | size_t len, loff_t *ppos) | |
1532 | { | |
1533 | struct msc_iter *iter = file->private_data; | |
1534 | struct msc *msc = iter->msc; | |
1535 | size_t size; | |
1536 | loff_t off = *ppos; | |
1537 | ssize_t ret = 0; | |
1538 | ||
1539 | if (!atomic_inc_unless_negative(&msc->user_count)) | |
1540 | return 0; | |
1541 | ||
ba82664c AS |
1542 | if (msc->mode == MSC_MODE_SINGLE && !msc->single_wrap) |
1543 | size = msc->single_sz; | |
1544 | else | |
1545 | size = msc->nr_pages << PAGE_SHIFT; | |
1546 | ||
1547 | if (!size) | |
2bed074a | 1548 | goto put_count; |
ba82664c | 1549 | |
2bed074a | 1550 | if (off >= size) |
ba82664c | 1551 | goto put_count; |
2bed074a | 1552 | |
ba82664c AS |
1553 | if (off + len >= size) |
1554 | len = size - off; | |
1555 | ||
1556 | if (msc->mode == MSC_MODE_SINGLE) { | |
1557 | ret = msc_single_to_user(msc, buf, off, len); | |
1558 | if (ret >= 0) | |
1559 | *ppos += ret; | |
1560 | } else if (msc->mode == MSC_MODE_MULTI) { | |
1561 | struct msc_win_to_user_struct u = { | |
1562 | .buf = buf, | |
1563 | .offset = 0, | |
1564 | }; | |
1565 | ||
1566 | ret = msc_buffer_iterate(iter, len, &u, msc_win_to_user); | |
1567 | if (ret >= 0) | |
1568 | *ppos = iter->offset; | |
1569 | } else { | |
ce666be8 | 1570 | ret = -EINVAL; |
ba82664c AS |
1571 | } |
1572 | ||
1573 | put_count: | |
1574 | atomic_dec(&msc->user_count); | |
1575 | ||
1576 | return ret; | |
1577 | } | |
1578 | ||
1579 | /* | |
1580 | * vm operations callbacks (vm_ops) | |
1581 | */ | |
1582 | ||
1583 | static void msc_mmap_open(struct vm_area_struct *vma) | |
1584 | { | |
1585 | struct msc_iter *iter = vma->vm_file->private_data; | |
1586 | struct msc *msc = iter->msc; | |
1587 | ||
1588 | atomic_inc(&msc->mmap_count); | |
1589 | } | |
1590 | ||
1591 | static void msc_mmap_close(struct vm_area_struct *vma) | |
1592 | { | |
1593 | struct msc_iter *iter = vma->vm_file->private_data; | |
1594 | struct msc *msc = iter->msc; | |
1595 | unsigned long pg; | |
1596 | ||
1597 | if (!atomic_dec_and_mutex_lock(&msc->mmap_count, &msc->buf_mutex)) | |
1598 | return; | |
1599 | ||
0139aa7b | 1600 | /* drop page _refcounts */ |
ba82664c AS |
1601 | for (pg = 0; pg < msc->nr_pages; pg++) { |
1602 | struct page *page = msc_buffer_get_page(msc, pg); | |
1603 | ||
1604 | if (WARN_ON_ONCE(!page)) | |
1605 | continue; | |
1606 | ||
1607 | if (page->mapping) | |
1608 | page->mapping = NULL; | |
1609 | } | |
1610 | ||
1611 | /* last mapping -- drop user_count */ | |
1612 | atomic_dec(&msc->user_count); | |
1613 | mutex_unlock(&msc->buf_mutex); | |
1614 | } | |
1615 | ||
42df0509 | 1616 | static vm_fault_t msc_mmap_fault(struct vm_fault *vmf) |
ba82664c | 1617 | { |
11bac800 | 1618 | struct msc_iter *iter = vmf->vma->vm_file->private_data; |
ba82664c AS |
1619 | struct msc *msc = iter->msc; |
1620 | ||
1621 | vmf->page = msc_buffer_get_page(msc, vmf->pgoff); | |
1622 | if (!vmf->page) | |
1623 | return VM_FAULT_SIGBUS; | |
1624 | ||
1625 | get_page(vmf->page); | |
11bac800 | 1626 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
ba82664c AS |
1627 | vmf->page->index = vmf->pgoff; |
1628 | ||
1629 | return 0; | |
1630 | } | |
1631 | ||
1632 | static const struct vm_operations_struct msc_mmap_ops = { | |
1633 | .open = msc_mmap_open, | |
1634 | .close = msc_mmap_close, | |
1635 | .fault = msc_mmap_fault, | |
1636 | }; | |
1637 | ||
1638 | static int intel_th_msc_mmap(struct file *file, struct vm_area_struct *vma) | |
1639 | { | |
1640 | unsigned long size = vma->vm_end - vma->vm_start; | |
1641 | struct msc_iter *iter = vma->vm_file->private_data; | |
1642 | struct msc *msc = iter->msc; | |
1643 | int ret = -EINVAL; | |
1644 | ||
1645 | if (!size || offset_in_page(size)) | |
1646 | return -EINVAL; | |
1647 | ||
1648 | if (vma->vm_pgoff) | |
1649 | return -EINVAL; | |
1650 | ||
1651 | /* grab user_count once per mmap; drop in msc_mmap_close() */ | |
1652 | if (!atomic_inc_unless_negative(&msc->user_count)) | |
1653 | return -EINVAL; | |
1654 | ||
1655 | if (msc->mode != MSC_MODE_SINGLE && | |
1656 | msc->mode != MSC_MODE_MULTI) | |
1657 | goto out; | |
1658 | ||
1659 | if (size >> PAGE_SHIFT != msc->nr_pages) | |
1660 | goto out; | |
1661 | ||
1662 | atomic_set(&msc->mmap_count, 1); | |
1663 | ret = 0; | |
1664 | ||
1665 | out: | |
1666 | if (ret) | |
1667 | atomic_dec(&msc->user_count); | |
1668 | ||
1669 | vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); | |
1c71222e | 1670 | vm_flags_set(vma, VM_DONTEXPAND | VM_DONTCOPY); |
ba82664c AS |
1671 | vma->vm_ops = &msc_mmap_ops; |
1672 | return ret; | |
1673 | } | |
1674 | ||
1675 | static const struct file_operations intel_th_msc_fops = { | |
1676 | .open = intel_th_msc_open, | |
1677 | .release = intel_th_msc_release, | |
1678 | .read = intel_th_msc_read, | |
1679 | .mmap = intel_th_msc_mmap, | |
8e9a2beb | 1680 | .owner = THIS_MODULE, |
ba82664c AS |
1681 | }; |
1682 | ||
8d415512 AS |
1683 | static void intel_th_msc_wait_empty(struct intel_th_device *thdev) |
1684 | { | |
1685 | struct msc *msc = dev_get_drvdata(&thdev->dev); | |
1686 | unsigned long count; | |
1687 | u32 reg; | |
1688 | ||
1689 | for (reg = 0, count = MSC_PLE_WAITLOOP_DEPTH; | |
1690 | count && !(reg & MSCSTS_PLE); count--) { | |
1691 | reg = __raw_readl(msc->reg_base + REG_MSU_MSC0STS); | |
1692 | cpu_relax(); | |
1693 | } | |
1694 | ||
1695 | if (!count) | |
1696 | dev_dbg(msc_dev(msc), "timeout waiting for MSC0 PLE\n"); | |
1697 | } | |
1698 | ||
ba82664c AS |
1699 | static int intel_th_msc_init(struct msc *msc) |
1700 | { | |
1701 | atomic_set(&msc->user_count, -1); | |
1702 | ||
397c7729 | 1703 | msc->mode = msc->multi_is_broken ? MSC_MODE_SINGLE : MSC_MODE_MULTI; |
ba82664c AS |
1704 | mutex_init(&msc->buf_mutex); |
1705 | INIT_LIST_HEAD(&msc->win_list); | |
ba82664c AS |
1706 | INIT_LIST_HEAD(&msc->iter_list); |
1707 | ||
1708 | msc->burst_len = | |
1709 | (ioread32(msc->reg_base + REG_MSU_MSC0CTL) & MSC_LEN) >> | |
1710 | __ffs(MSC_LEN); | |
1711 | ||
1712 | return 0; | |
1713 | } | |
1714 | ||
05b686b5 | 1715 | static int msc_win_switch(struct msc *msc) |
aad14ad3 | 1716 | { |
9800db28 | 1717 | struct msc_window *first; |
aad14ad3 | 1718 | |
05b686b5 AS |
1719 | if (list_empty(&msc->win_list)) |
1720 | return -EINVAL; | |
1721 | ||
aad14ad3 | 1722 | first = list_first_entry(&msc->win_list, struct msc_window, entry); |
aad14ad3 AS |
1723 | |
1724 | if (msc_is_last_win(msc->cur_win)) | |
1725 | msc->cur_win = first; | |
1726 | else | |
1727 | msc->cur_win = list_next_entry(msc->cur_win, entry); | |
1728 | ||
57b69a1f AS |
1729 | msc->base = msc_win_base(msc->cur_win); |
1730 | msc->base_addr = msc_win_base_dma(msc->cur_win); | |
aad14ad3 AS |
1731 | |
1732 | intel_th_trace_switch(msc->thdev); | |
05b686b5 AS |
1733 | |
1734 | return 0; | |
aad14ad3 AS |
1735 | } |
1736 | ||
615c164d AS |
1737 | /** |
1738 | * intel_th_msc_window_unlock - put the window back in rotation | |
1739 | * @dev: MSC device to which this relates | |
1740 | * @sgt: buffer's sg_table for the window, does nothing if NULL | |
1741 | */ | |
1742 | void intel_th_msc_window_unlock(struct device *dev, struct sg_table *sgt) | |
1743 | { | |
1744 | struct msc *msc = dev_get_drvdata(dev); | |
1745 | struct msc_window *win; | |
1746 | ||
1747 | if (!sgt) | |
1748 | return; | |
1749 | ||
1750 | win = msc_find_window(msc, sgt, false); | |
1751 | if (!win) | |
1752 | return; | |
1753 | ||
1754 | msc_win_set_lockout(win, WIN_LOCKED, WIN_READY); | |
8622dfef AS |
1755 | if (msc->switch_on_unlock == win) { |
1756 | msc->switch_on_unlock = NULL; | |
1757 | msc_win_switch(msc); | |
1758 | } | |
615c164d AS |
1759 | } |
1760 | EXPORT_SYMBOL_GPL(intel_th_msc_window_unlock); | |
1761 | ||
1762 | static void msc_work(struct work_struct *work) | |
1763 | { | |
1764 | struct msc *msc = container_of(work, struct msc, work); | |
1765 | ||
1766 | intel_th_msc_deactivate(msc->thdev); | |
1767 | } | |
1768 | ||
aac8da65 AS |
1769 | static irqreturn_t intel_th_msc_interrupt(struct intel_th_device *thdev) |
1770 | { | |
1771 | struct msc *msc = dev_get_drvdata(&thdev->dev); | |
1772 | u32 msusts = ioread32(msc->msu_base + REG_MSU_MSUSTS); | |
1773 | u32 mask = msc->index ? MSUSTS_MSC1BLAST : MSUSTS_MSC0BLAST; | |
615c164d | 1774 | struct msc_window *win, *next_win; |
aac8da65 | 1775 | |
615c164d | 1776 | if (!msc->do_irq || !msc->mbuf) |
aac8da65 | 1777 | return IRQ_NONE; |
615c164d AS |
1778 | |
1779 | msusts &= mask; | |
1780 | ||
1781 | if (!msusts) | |
1782 | return msc->enabled ? IRQ_HANDLED : IRQ_NONE; | |
1783 | ||
1784 | iowrite32(msusts, msc->msu_base + REG_MSU_MSUSTS); | |
1785 | ||
1786 | if (!msc->enabled) | |
1787 | return IRQ_NONE; | |
1788 | ||
1789 | /* grab the window before we do the switch */ | |
1790 | win = msc->cur_win; | |
1791 | if (!win) | |
1792 | return IRQ_HANDLED; | |
1793 | next_win = msc_next_window(win); | |
1794 | if (!next_win) | |
1795 | return IRQ_HANDLED; | |
1796 | ||
1797 | /* next window: if READY, proceed, if LOCKED, stop the trace */ | |
1798 | if (msc_win_set_lockout(next_win, WIN_READY, WIN_INUSE)) { | |
8622dfef AS |
1799 | if (msc->stop_on_full) |
1800 | schedule_work(&msc->work); | |
1801 | else | |
1802 | msc->switch_on_unlock = next_win; | |
1803 | ||
615c164d | 1804 | return IRQ_HANDLED; |
aac8da65 AS |
1805 | } |
1806 | ||
615c164d AS |
1807 | /* current window: INUSE -> LOCKED */ |
1808 | msc_win_set_lockout(win, WIN_INUSE, WIN_LOCKED); | |
1809 | ||
1810 | msc_win_switch(msc); | |
1811 | ||
1812 | if (msc->mbuf && msc->mbuf->ready) | |
1813 | msc->mbuf->ready(msc->mbuf_priv, win->sgt, | |
1814 | msc_win_total_sz(win)); | |
1815 | ||
aac8da65 AS |
1816 | return IRQ_HANDLED; |
1817 | } | |
1818 | ||
ba82664c AS |
1819 | static const char * const msc_mode[] = { |
1820 | [MSC_MODE_SINGLE] = "single", | |
1821 | [MSC_MODE_MULTI] = "multi", | |
1822 | [MSC_MODE_EXI] = "ExI", | |
1823 | [MSC_MODE_DEBUG] = "debug", | |
1824 | }; | |
1825 | ||
1826 | static ssize_t | |
1827 | wrap_show(struct device *dev, struct device_attribute *attr, char *buf) | |
1828 | { | |
1829 | struct msc *msc = dev_get_drvdata(dev); | |
1830 | ||
1831 | return scnprintf(buf, PAGE_SIZE, "%d\n", msc->wrap); | |
1832 | } | |
1833 | ||
1834 | static ssize_t | |
1835 | wrap_store(struct device *dev, struct device_attribute *attr, const char *buf, | |
1836 | size_t size) | |
1837 | { | |
1838 | struct msc *msc = dev_get_drvdata(dev); | |
1839 | unsigned long val; | |
1840 | int ret; | |
1841 | ||
1842 | ret = kstrtoul(buf, 10, &val); | |
1843 | if (ret) | |
1844 | return ret; | |
1845 | ||
1846 | msc->wrap = !!val; | |
1847 | ||
1848 | return size; | |
1849 | } | |
1850 | ||
1851 | static DEVICE_ATTR_RW(wrap); | |
1852 | ||
615c164d AS |
1853 | static void msc_buffer_unassign(struct msc *msc) |
1854 | { | |
1855 | lockdep_assert_held(&msc->buf_mutex); | |
1856 | ||
1857 | if (!msc->mbuf) | |
1858 | return; | |
1859 | ||
1860 | msc->mbuf->unassign(msc->mbuf_priv); | |
1861 | msu_buffer_put(msc->mbuf); | |
1862 | msc->mbuf_priv = NULL; | |
1863 | msc->mbuf = NULL; | |
1864 | } | |
1865 | ||
ba82664c AS |
1866 | static ssize_t |
1867 | mode_show(struct device *dev, struct device_attribute *attr, char *buf) | |
1868 | { | |
1869 | struct msc *msc = dev_get_drvdata(dev); | |
615c164d AS |
1870 | const char *mode = msc_mode[msc->mode]; |
1871 | ssize_t ret; | |
1872 | ||
1873 | mutex_lock(&msc->buf_mutex); | |
1874 | if (msc->mbuf) | |
1875 | mode = msc->mbuf->name; | |
1876 | ret = scnprintf(buf, PAGE_SIZE, "%s\n", mode); | |
1877 | mutex_unlock(&msc->buf_mutex); | |
ba82664c | 1878 | |
615c164d | 1879 | return ret; |
ba82664c AS |
1880 | } |
1881 | ||
1882 | static ssize_t | |
1883 | mode_store(struct device *dev, struct device_attribute *attr, const char *buf, | |
1884 | size_t size) | |
1885 | { | |
615c164d | 1886 | const struct msu_buffer *mbuf = NULL; |
ba82664c AS |
1887 | struct msc *msc = dev_get_drvdata(dev); |
1888 | size_t len = size; | |
615c164d | 1889 | char *cp, *mode; |
ba82664c AS |
1890 | int i, ret; |
1891 | ||
1892 | if (!capable(CAP_SYS_RAWIO)) | |
1893 | return -EPERM; | |
1894 | ||
1895 | cp = memchr(buf, '\n', len); | |
1896 | if (cp) | |
1897 | len = cp - buf; | |
1898 | ||
615c164d | 1899 | mode = kstrndup(buf, len, GFP_KERNEL); |
063f097f CIK |
1900 | if (!mode) |
1901 | return -ENOMEM; | |
1902 | ||
615c164d | 1903 | i = match_string(msc_mode, ARRAY_SIZE(msc_mode), mode); |
1fa1b6ca WY |
1904 | if (i >= 0) { |
1905 | kfree(mode); | |
615c164d | 1906 | goto found; |
1fa1b6ca | 1907 | } |
615c164d AS |
1908 | |
1909 | /* Buffer sinks only work with a usable IRQ */ | |
1910 | if (!msc->do_irq) { | |
1911 | kfree(mode); | |
1912 | return -EINVAL; | |
1913 | } | |
1914 | ||
1915 | mbuf = msu_buffer_get(mode); | |
1916 | kfree(mode); | |
1917 | if (mbuf) | |
1918 | goto found; | |
ba82664c AS |
1919 | |
1920 | return -EINVAL; | |
1921 | ||
1922 | found: | |
397c7729 AS |
1923 | if (i == MSC_MODE_MULTI && msc->multi_is_broken) |
1924 | return -EOPNOTSUPP; | |
1925 | ||
ba82664c | 1926 | mutex_lock(&msc->buf_mutex); |
615c164d AS |
1927 | ret = 0; |
1928 | ||
1929 | /* Same buffer: do nothing */ | |
1930 | if (mbuf && mbuf == msc->mbuf) { | |
1931 | /* put the extra reference we just got */ | |
1932 | msu_buffer_put(mbuf); | |
1933 | goto unlock; | |
1934 | } | |
1935 | ||
ba82664c | 1936 | ret = msc_buffer_unlocked_free_unless_used(msc); |
615c164d AS |
1937 | if (ret) |
1938 | goto unlock; | |
1939 | ||
1940 | if (mbuf) { | |
1941 | void *mbuf_priv = mbuf->assign(dev, &i); | |
1942 | ||
1943 | if (!mbuf_priv) { | |
1944 | ret = -ENOMEM; | |
1945 | goto unlock; | |
1946 | } | |
1947 | ||
1948 | msc_buffer_unassign(msc); | |
1949 | msc->mbuf_priv = mbuf_priv; | |
1950 | msc->mbuf = mbuf; | |
1951 | } else { | |
1952 | msc_buffer_unassign(msc); | |
1953 | } | |
1954 | ||
1955 | msc->mode = i; | |
1956 | ||
1957 | unlock: | |
1958 | if (ret && mbuf) | |
1959 | msu_buffer_put(mbuf); | |
ba82664c AS |
1960 | mutex_unlock(&msc->buf_mutex); |
1961 | ||
1962 | return ret ? ret : size; | |
1963 | } | |
1964 | ||
1965 | static DEVICE_ATTR_RW(mode); | |
1966 | ||
1967 | static ssize_t | |
1968 | nr_pages_show(struct device *dev, struct device_attribute *attr, char *buf) | |
1969 | { | |
1970 | struct msc *msc = dev_get_drvdata(dev); | |
1971 | struct msc_window *win; | |
1972 | size_t count = 0; | |
1973 | ||
1974 | mutex_lock(&msc->buf_mutex); | |
1975 | ||
1976 | if (msc->mode == MSC_MODE_SINGLE) | |
1977 | count = scnprintf(buf, PAGE_SIZE, "%ld\n", msc->nr_pages); | |
1978 | else if (msc->mode == MSC_MODE_MULTI) { | |
1979 | list_for_each_entry(win, &msc->win_list, entry) { | |
1980 | count += scnprintf(buf + count, PAGE_SIZE - count, | |
1981 | "%d%c", win->nr_blocks, | |
1982 | msc_is_last_win(win) ? '\n' : ','); | |
1983 | } | |
1984 | } else { | |
1985 | count = scnprintf(buf, PAGE_SIZE, "unsupported\n"); | |
1986 | } | |
1987 | ||
1988 | mutex_unlock(&msc->buf_mutex); | |
1989 | ||
1990 | return count; | |
1991 | } | |
1992 | ||
1993 | static ssize_t | |
1994 | nr_pages_store(struct device *dev, struct device_attribute *attr, | |
1995 | const char *buf, size_t size) | |
1996 | { | |
1997 | struct msc *msc = dev_get_drvdata(dev); | |
1998 | unsigned long val, *win = NULL, *rewin; | |
1999 | size_t len = size; | |
2000 | const char *p = buf; | |
2001 | char *end, *s; | |
2002 | int ret, nr_wins = 0; | |
2003 | ||
2004 | if (!capable(CAP_SYS_RAWIO)) | |
2005 | return -EPERM; | |
2006 | ||
2007 | ret = msc_buffer_free_unless_used(msc); | |
2008 | if (ret) | |
2009 | return ret; | |
2010 | ||
2011 | /* scan the comma-separated list of allocation sizes */ | |
2012 | end = memchr(buf, '\n', len); | |
2013 | if (end) | |
2014 | len = end - buf; | |
2015 | ||
2016 | do { | |
2017 | end = memchr(p, ',', len); | |
2018 | s = kstrndup(p, end ? end - p : len, GFP_KERNEL); | |
6575cbd6 AS |
2019 | if (!s) { |
2020 | ret = -ENOMEM; | |
2021 | goto free_win; | |
2022 | } | |
2023 | ||
ba82664c AS |
2024 | ret = kstrtoul(s, 10, &val); |
2025 | kfree(s); | |
2026 | ||
2027 | if (ret || !val) | |
2028 | goto free_win; | |
2029 | ||
2030 | if (nr_wins && msc->mode == MSC_MODE_SINGLE) { | |
2031 | ret = -EINVAL; | |
2032 | goto free_win; | |
2033 | } | |
2034 | ||
2035 | nr_wins++; | |
f8f7e2bf | 2036 | rewin = krealloc_array(win, nr_wins, sizeof(*win), GFP_KERNEL); |
ba82664c AS |
2037 | if (!rewin) { |
2038 | kfree(win); | |
2039 | return -ENOMEM; | |
2040 | } | |
2041 | ||
2042 | win = rewin; | |
2043 | win[nr_wins - 1] = val; | |
2044 | ||
2045 | if (!end) | |
2046 | break; | |
2047 | ||
ec5b5ad6 AS |
2048 | /* consume the number and the following comma, hence +1 */ |
2049 | len -= end - p + 1; | |
ba82664c AS |
2050 | p = end + 1; |
2051 | } while (len); | |
2052 | ||
2053 | mutex_lock(&msc->buf_mutex); | |
2054 | ret = msc_buffer_alloc(msc, win, nr_wins); | |
2055 | mutex_unlock(&msc->buf_mutex); | |
2056 | ||
2057 | free_win: | |
2058 | kfree(win); | |
2059 | ||
2060 | return ret ? ret : size; | |
2061 | } | |
2062 | ||
2063 | static DEVICE_ATTR_RW(nr_pages); | |
2064 | ||
6cac7866 AS |
2065 | static ssize_t |
2066 | win_switch_store(struct device *dev, struct device_attribute *attr, | |
2067 | const char *buf, size_t size) | |
2068 | { | |
2069 | struct msc *msc = dev_get_drvdata(dev); | |
2070 | unsigned long val; | |
2071 | int ret; | |
2072 | ||
2073 | ret = kstrtoul(buf, 10, &val); | |
2074 | if (ret) | |
2075 | return ret; | |
2076 | ||
2077 | if (val != 1) | |
2078 | return -EINVAL; | |
2079 | ||
05b686b5 | 2080 | ret = -EINVAL; |
6cac7866 | 2081 | mutex_lock(&msc->buf_mutex); |
615c164d AS |
2082 | /* |
2083 | * Window switch can only happen in the "multi" mode. | |
2084 | * If a external buffer is engaged, they have the full | |
2085 | * control over window switching. | |
2086 | */ | |
05b686b5 AS |
2087 | if (msc->mode == MSC_MODE_MULTI && !msc->mbuf) |
2088 | ret = msc_win_switch(msc); | |
6cac7866 AS |
2089 | mutex_unlock(&msc->buf_mutex); |
2090 | ||
2091 | return ret ? ret : size; | |
2092 | } | |
2093 | ||
2094 | static DEVICE_ATTR_WO(win_switch); | |
2095 | ||
8622dfef AS |
2096 | static ssize_t stop_on_full_show(struct device *dev, |
2097 | struct device_attribute *attr, char *buf) | |
2098 | { | |
2099 | struct msc *msc = dev_get_drvdata(dev); | |
2100 | ||
2101 | return sprintf(buf, "%d\n", msc->stop_on_full); | |
2102 | } | |
2103 | ||
2104 | static ssize_t stop_on_full_store(struct device *dev, | |
2105 | struct device_attribute *attr, | |
2106 | const char *buf, size_t size) | |
2107 | { | |
2108 | struct msc *msc = dev_get_drvdata(dev); | |
2109 | int ret; | |
2110 | ||
2111 | ret = kstrtobool(buf, &msc->stop_on_full); | |
2112 | if (ret) | |
2113 | return ret; | |
2114 | ||
2115 | return size; | |
2116 | } | |
2117 | ||
2118 | static DEVICE_ATTR_RW(stop_on_full); | |
2119 | ||
ba82664c AS |
2120 | static struct attribute *msc_output_attrs[] = { |
2121 | &dev_attr_wrap.attr, | |
2122 | &dev_attr_mode.attr, | |
2123 | &dev_attr_nr_pages.attr, | |
6cac7866 | 2124 | &dev_attr_win_switch.attr, |
8622dfef | 2125 | &dev_attr_stop_on_full.attr, |
ba82664c AS |
2126 | NULL, |
2127 | }; | |
2128 | ||
d9962f6f | 2129 | static const struct attribute_group msc_output_group = { |
ba82664c AS |
2130 | .attrs = msc_output_attrs, |
2131 | }; | |
2132 | ||
2133 | static int intel_th_msc_probe(struct intel_th_device *thdev) | |
2134 | { | |
2135 | struct device *dev = &thdev->dev; | |
2136 | struct resource *res; | |
2137 | struct msc *msc; | |
2138 | void __iomem *base; | |
2139 | int err; | |
2140 | ||
2141 | res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0); | |
2142 | if (!res) | |
2143 | return -ENODEV; | |
2144 | ||
2145 | base = devm_ioremap(dev, res->start, resource_size(res)); | |
73061da0 DC |
2146 | if (!base) |
2147 | return -ENOMEM; | |
ba82664c AS |
2148 | |
2149 | msc = devm_kzalloc(dev, sizeof(*msc), GFP_KERNEL); | |
2150 | if (!msc) | |
2151 | return -ENOMEM; | |
2152 | ||
aac8da65 AS |
2153 | res = intel_th_device_get_resource(thdev, IORESOURCE_IRQ, 1); |
2154 | if (!res) | |
2155 | msc->do_irq = 1; | |
2156 | ||
397c7729 AS |
2157 | if (INTEL_TH_CAP(to_intel_th(thdev), multi_is_broken)) |
2158 | msc->multi_is_broken = 1; | |
2159 | ||
ba82664c AS |
2160 | msc->index = thdev->id; |
2161 | ||
2162 | msc->thdev = thdev; | |
2163 | msc->reg_base = base + msc->index * 0x100; | |
aac8da65 AS |
2164 | msc->msu_base = base; |
2165 | ||
615c164d | 2166 | INIT_WORK(&msc->work, msc_work); |
ba82664c AS |
2167 | err = intel_th_msc_init(msc); |
2168 | if (err) | |
2169 | return err; | |
2170 | ||
ba82664c AS |
2171 | dev_set_drvdata(dev, msc); |
2172 | ||
2173 | return 0; | |
2174 | } | |
2175 | ||
2176 | static void intel_th_msc_remove(struct intel_th_device *thdev) | |
2177 | { | |
f152dfee AS |
2178 | struct msc *msc = dev_get_drvdata(&thdev->dev); |
2179 | int ret; | |
2180 | ||
2181 | intel_th_msc_deactivate(thdev); | |
2182 | ||
2183 | /* | |
2184 | * Buffers should not be used at this point except if the | |
2185 | * output character device is still open and the parent | |
2186 | * device gets detached from its bus, which is a FIXME. | |
2187 | */ | |
2188 | ret = msc_buffer_free_unless_used(msc); | |
2189 | WARN_ON_ONCE(ret); | |
ba82664c AS |
2190 | } |
2191 | ||
2192 | static struct intel_th_driver intel_th_msc_driver = { | |
2193 | .probe = intel_th_msc_probe, | |
2194 | .remove = intel_th_msc_remove, | |
aac8da65 | 2195 | .irq = intel_th_msc_interrupt, |
8d415512 | 2196 | .wait_empty = intel_th_msc_wait_empty, |
ba82664c AS |
2197 | .activate = intel_th_msc_activate, |
2198 | .deactivate = intel_th_msc_deactivate, | |
2199 | .fops = &intel_th_msc_fops, | |
9d482aed | 2200 | .attr_group = &msc_output_group, |
ba82664c AS |
2201 | .driver = { |
2202 | .name = "msc", | |
2203 | .owner = THIS_MODULE, | |
2204 | }, | |
2205 | }; | |
2206 | ||
2207 | module_driver(intel_th_msc_driver, | |
2208 | intel_th_driver_register, | |
2209 | intel_th_driver_unregister); | |
2210 | ||
2211 | MODULE_LICENSE("GPL v2"); | |
2212 | MODULE_DESCRIPTION("Intel(R) Trace Hub Memory Storage Unit driver"); | |
2213 | MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>"); |