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1 From e96d7ea9022d8b49644c2f150da162728b948c43 Mon Sep 17 00:00:00 2001
2 From: yaroslavros <yaroslavros@gmail.com>
3 Date: Wed, 14 Aug 2019 15:22:55 +0100
4 Subject: [PATCH 767/782] Ported pcie-brcmstb bounce buffer implementation to
5 ARM64. (#3144)
6
7 Ported pcie-brcmstb bounce buffer implementation to ARM64.
8 This enables full 4G RAM usage on Raspberry Pi in 64-bit mode.
9
10 Signed-off-by: Yaroslav Rosomakho <yaroslavros@gmail.com>
11 ---
12 arch/arm64/include/asm/dma-mapping.h | 21 +
13 arch/arm64/mm/dma-mapping.c | 50 ++
14 drivers/pci/controller/Makefile | 3 +
15 drivers/pci/controller/pcie-brcmstb-bounce.h | 2 +-
16 .../pci/controller/pcie-brcmstb-bounce64.c | 576 ++++++++++++++++++
17 drivers/pci/controller/pcie-brcmstb.c | 30 +-
18 6 files changed, 658 insertions(+), 24 deletions(-)
19 create mode 100644 drivers/pci/controller/pcie-brcmstb-bounce64.c
20
21 --- a/arch/arm64/include/asm/dma-mapping.h
22 +++ b/arch/arm64/include/asm/dma-mapping.h
23 @@ -24,6 +24,27 @@
24 #include <xen/xen.h>
25 #include <asm/xen/hypervisor.h>
26
27 +extern void *arm64_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
28 + gfp_t gfp, unsigned long attrs);
29 +extern void arm64_dma_free(struct device *dev, size_t size, void *cpu_addr,
30 + dma_addr_t handle, unsigned long attrs);
31 +extern int arm64_dma_mmap(struct device *dev, struct vm_area_struct *vma,
32 + void *cpu_addr, dma_addr_t dma_addr, size_t size,
33 + unsigned long attrs);
34 +extern int arm64_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
35 + void *cpu_addr, dma_addr_t dma_addr, size_t size,
36 + unsigned long attrs);
37 +extern int arm64_dma_map_sg(struct device *dev, struct scatterlist *sgl, int nelems,
38 + enum dma_data_direction dir, unsigned long attrs);
39 +extern void arm64_dma_unmap_sg(struct device *dev, struct scatterlist *sgl, int,
40 + enum dma_data_direction dir, unsigned long attrs);
41 +extern void arm64_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sgl, int nelems,
42 + enum dma_data_direction dir);
43 +extern void arm64_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, int nelems,
44 + enum dma_data_direction dir);
45 +
46 +
47 +
48 extern const struct dma_map_ops dummy_dma_ops;
49
50 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
51 --- a/arch/arm64/mm/dma-mapping.c
52 +++ b/arch/arm64/mm/dma-mapping.c
53 @@ -138,6 +138,12 @@ no_mem:
54 return NULL;
55 }
56
57 +void *arm64_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
58 + gfp_t gfp, unsigned long attrs)
59 +{
60 + return __dma_alloc(dev, size, handle, gfp, attrs);
61 +}
62 +
63 static void __dma_free(struct device *dev, size_t size,
64 void *vaddr, dma_addr_t dma_handle,
65 unsigned long attrs)
66 @@ -154,6 +160,12 @@ static void __dma_free(struct device *de
67 swiotlb_free(dev, size, swiotlb_addr, dma_handle, attrs);
68 }
69
70 +void arm64_dma_free(struct device *dev, size_t size, void *cpu_addr,
71 + dma_addr_t handle, unsigned long attrs)
72 +{
73 + __dma_free(dev, size, cpu_addr, handle, attrs);
74 +}
75 +
76 static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
77 unsigned long offset, size_t size,
78 enum dma_data_direction dir,
79 @@ -197,6 +209,12 @@ static int __swiotlb_map_sg_attrs(struct
80 return ret;
81 }
82
83 +int arm64_dma_map_sg(struct device *dev, struct scatterlist *sgl, int nelems,
84 + enum dma_data_direction dir, unsigned long attrs)
85 +{
86 + return __swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
87 +}
88 +
89 static void __swiotlb_unmap_sg_attrs(struct device *dev,
90 struct scatterlist *sgl, int nelems,
91 enum dma_data_direction dir,
92 @@ -213,6 +231,12 @@ static void __swiotlb_unmap_sg_attrs(str
93 swiotlb_unmap_sg_attrs(dev, sgl, nelems, dir, attrs);
94 }
95
96 +void arm64_dma_unmap_sg(struct device *dev, struct scatterlist *sgl, int nelems,
97 + enum dma_data_direction dir, unsigned long attrs)
98 +{
99 + __swiotlb_unmap_sg_attrs(dev, sgl, nelems, dir, attrs);
100 +}
101 +
102 static void __swiotlb_sync_single_for_cpu(struct device *dev,
103 dma_addr_t dev_addr, size_t size,
104 enum dma_data_direction dir)
105 @@ -245,6 +269,12 @@ static void __swiotlb_sync_sg_for_cpu(st
106 swiotlb_sync_sg_for_cpu(dev, sgl, nelems, dir);
107 }
108
109 +void arm64_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sgl, int nelems,
110 + enum dma_data_direction dir)
111 +{
112 + __swiotlb_sync_sg_for_cpu(dev, sgl, nelems, dir);
113 +}
114 +
115 static void __swiotlb_sync_sg_for_device(struct device *dev,
116 struct scatterlist *sgl, int nelems,
117 enum dma_data_direction dir)
118 @@ -259,6 +289,12 @@ static void __swiotlb_sync_sg_for_device
119 sg->length, dir);
120 }
121
122 +void arm64_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, int nelems,
123 + enum dma_data_direction dir)
124 +{
125 + __swiotlb_sync_sg_for_device(dev, sgl, nelems, dir);
126 +}
127 +
128 static int __swiotlb_mmap_pfn(struct vm_area_struct *vma,
129 unsigned long pfn, size_t size)
130 {
131 @@ -294,6 +330,13 @@ static int __swiotlb_mmap(struct device
132 return __swiotlb_mmap_pfn(vma, pfn, size);
133 }
134
135 +int arm64_dma_mmap(struct device *dev, struct vm_area_struct *vma,
136 + void *cpu_addr, dma_addr_t dma_addr, size_t size,
137 + unsigned long attrs)
138 +{
139 + return __swiotlb_mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
140 +}
141 +
142 static int __swiotlb_get_sgtable_page(struct sg_table *sgt,
143 struct page *page, size_t size)
144 {
145 @@ -314,6 +357,13 @@ static int __swiotlb_get_sgtable(struct
146 return __swiotlb_get_sgtable_page(sgt, page, size);
147 }
148
149 +int arm64_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
150 + void *cpu_addr, dma_addr_t dma_addr, size_t size,
151 + unsigned long attrs)
152 +{
153 + return __swiotlb_get_sgtable(dev, sgt, cpu_addr, dma_addr, size, attrs);
154 +}
155 +
156 static int __swiotlb_dma_supported(struct device *hwdev, u64 mask)
157 {
158 if (swiotlb)
159 --- a/drivers/pci/controller/Makefile
160 +++ b/drivers/pci/controller/Makefile
161 @@ -32,6 +32,9 @@ obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcms
162 ifdef CONFIG_ARM
163 obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb-bounce.o
164 endif
165 +ifdef CONFIG_ARM64
166 +obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb-bounce64.o
167 +endif
168
169 obj-$(CONFIG_VMD) += vmd.o
170 # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
171 --- a/drivers/pci/controller/pcie-brcmstb-bounce.h
172 +++ b/drivers/pci/controller/pcie-brcmstb-bounce.h
173 @@ -6,7 +6,7 @@
174 #ifndef _PCIE_BRCMSTB_BOUNCE_H
175 #define _PCIE_BRCMSTB_BOUNCE_H
176
177 -#ifdef CONFIG_ARM
178 +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
179
180 int brcm_pcie_bounce_init(struct device *dev, unsigned long buffer_size,
181 dma_addr_t threshold);
182 --- /dev/null
183 +++ b/drivers/pci/controller/pcie-brcmstb-bounce64.c
184 @@ -0,0 +1,576 @@
185 +/*
186 + * This code started out as a version of arch/arm/common/dmabounce.c,
187 + * modified to cope with highmem pages. Now it has been changed heavily -
188 + * it now preallocates a large block (currently 4MB) and carves it up
189 + * sequentially in ring fashion, and DMA is used to copy the data - to the
190 + * point where very little of the original remains.
191 + *
192 + * Copyright (C) 2019 Raspberry Pi (Trading) Ltd.
193 + *
194 + * Original version by Brad Parker (brad@heeltoe.com)
195 + * Re-written by Christopher Hoover <ch@murgatroid.com>
196 + * Made generic by Deepak Saxena <dsaxena@plexity.net>
197 + *
198 + * Copyright (C) 2002 Hewlett Packard Company.
199 + * Copyright (C) 2004 MontaVista Software, Inc.
200 + *
201 + * This program is free software; you can redistribute it and/or
202 + * modify it under the terms of the GNU General Public License
203 + * version 2 as published by the Free Software Foundation.
204 + */
205 +
206 +#include <linux/module.h>
207 +#include <linux/init.h>
208 +#include <linux/slab.h>
209 +#include <linux/page-flags.h>
210 +#include <linux/device.h>
211 +#include <linux/dma-mapping.h>
212 +#include <linux/dma-direct.h>
213 +#include <linux/dmapool.h>
214 +#include <linux/list.h>
215 +#include <linux/scatterlist.h>
216 +#include <linux/bitmap.h>
217 +#include <linux/swiotlb.h>
218 +
219 +#include <asm/cacheflush.h>
220 +
221 +#define STATS
222 +
223 +#ifdef STATS
224 +#define DO_STATS(X) do { X ; } while (0)
225 +#else
226 +#define DO_STATS(X) do { } while (0)
227 +#endif
228 +
229 +/* ************************************************** */
230 +
231 +struct safe_buffer {
232 + struct list_head node;
233 +
234 + /* original request */
235 + size_t size;
236 + int direction;
237 +
238 + struct dmabounce_pool *pool;
239 + void *safe;
240 + dma_addr_t unsafe_dma_addr;
241 + dma_addr_t safe_dma_addr;
242 +};
243 +
244 +struct dmabounce_pool {
245 + unsigned long pages;
246 + void *virt_addr;
247 + dma_addr_t dma_addr;
248 + unsigned long *alloc_map;
249 + unsigned long alloc_pos;
250 + spinlock_t lock;
251 + struct device *dev;
252 + unsigned long num_pages;
253 +#ifdef STATS
254 + size_t max_size;
255 + unsigned long num_bufs;
256 + unsigned long max_bufs;
257 + unsigned long max_pages;
258 +#endif
259 +};
260 +
261 +struct dmabounce_device_info {
262 + struct device *dev;
263 + dma_addr_t threshold;
264 + struct list_head safe_buffers;
265 + struct dmabounce_pool pool;
266 + rwlock_t lock;
267 +#ifdef STATS
268 + unsigned long map_count;
269 + unsigned long unmap_count;
270 + unsigned long sync_dev_count;
271 + unsigned long sync_cpu_count;
272 + unsigned long fail_count;
273 + int attr_res;
274 +#endif
275 +};
276 +
277 +static struct dmabounce_device_info *g_dmabounce_device_info;
278 +
279 +extern int bcm2838_dma40_memcpy_init(void);
280 +extern void bcm2838_dma40_memcpy(dma_addr_t dst, dma_addr_t src, size_t size);
281 +
282 +#ifdef STATS
283 +static ssize_t
284 +bounce_show(struct device *dev, struct device_attribute *attr, char *buf)
285 +{
286 + struct dmabounce_device_info *device_info = g_dmabounce_device_info;
287 + return sprintf(buf, "m:%lu/%lu s:%lu/%lu f:%lu s:%zu b:%lu/%lu a:%lu/%lu\n",
288 + device_info->map_count,
289 + device_info->unmap_count,
290 + device_info->sync_dev_count,
291 + device_info->sync_cpu_count,
292 + device_info->fail_count,
293 + device_info->pool.max_size,
294 + device_info->pool.num_bufs,
295 + device_info->pool.max_bufs,
296 + device_info->pool.num_pages * PAGE_SIZE,
297 + device_info->pool.max_pages * PAGE_SIZE);
298 +}
299 +
300 +static DEVICE_ATTR(dmabounce_stats, 0444, bounce_show, NULL);
301 +#endif
302 +
303 +static int bounce_create(struct dmabounce_pool *pool, struct device *dev,
304 + unsigned long buffer_size)
305 +{
306 + int ret = -ENOMEM;
307 + pool->pages = (buffer_size + PAGE_SIZE - 1)/PAGE_SIZE;
308 + pool->alloc_map = bitmap_zalloc(pool->pages, GFP_KERNEL);
309 + if (!pool->alloc_map)
310 + goto err_bitmap;
311 + pool->virt_addr = dma_alloc_coherent(dev, pool->pages * PAGE_SIZE,
312 + &pool->dma_addr, GFP_KERNEL);
313 + if (!pool->virt_addr)
314 + goto err_dmabuf;
315 +
316 + pool->alloc_pos = 0;
317 + spin_lock_init(&pool->lock);
318 + pool->dev = dev;
319 + pool->num_pages = 0;
320 +
321 + DO_STATS(pool->max_size = 0);
322 + DO_STATS(pool->num_bufs = 0);
323 + DO_STATS(pool->max_bufs = 0);
324 + DO_STATS(pool->max_pages = 0);
325 +
326 + return 0;
327 +
328 +err_dmabuf:
329 + bitmap_free(pool->alloc_map);
330 +err_bitmap:
331 + return ret;
332 +}
333 +
334 +static void bounce_destroy(struct dmabounce_pool *pool)
335 +{
336 + dma_free_coherent(pool->dev, pool->pages * PAGE_SIZE, pool->virt_addr,
337 + pool->dma_addr);
338 +
339 + bitmap_free(pool->alloc_map);
340 +}
341 +
342 +static void *bounce_alloc(struct dmabounce_pool *pool, size_t size,
343 + dma_addr_t *dmaaddrp)
344 +{
345 + unsigned long pages;
346 + unsigned long flags;
347 + unsigned long pos;
348 +
349 + pages = (size + PAGE_SIZE - 1)/PAGE_SIZE;
350 +
351 + DO_STATS(pool->max_size = max(size, pool->max_size));
352 +
353 + spin_lock_irqsave(&pool->lock, flags);
354 + pos = bitmap_find_next_zero_area(pool->alloc_map, pool->pages,
355 + pool->alloc_pos, pages, 0);
356 + /* If not found, try from the start */
357 + if (pos >= pool->pages && pool->alloc_pos)
358 + pos = bitmap_find_next_zero_area(pool->alloc_map, pool->pages,
359 + 0, pages, 0);
360 +
361 + if (pos >= pool->pages) {
362 + spin_unlock_irqrestore(&pool->lock, flags);
363 + return NULL;
364 + }
365 +
366 + bitmap_set(pool->alloc_map, pos, pages);
367 + pool->alloc_pos = (pos + pages) % pool->pages;
368 + pool->num_pages += pages;
369 +
370 + DO_STATS(pool->num_bufs++);
371 + DO_STATS(pool->max_bufs = max(pool->num_bufs, pool->max_bufs));
372 + DO_STATS(pool->max_pages = max(pool->num_pages, pool->max_pages));
373 +
374 + spin_unlock_irqrestore(&pool->lock, flags);
375 +
376 + *dmaaddrp = pool->dma_addr + pos * PAGE_SIZE;
377 +
378 + return pool->virt_addr + pos * PAGE_SIZE;
379 +}
380 +
381 +static void
382 +bounce_free(struct dmabounce_pool *pool, void *buf, size_t size)
383 +{
384 + unsigned long pages;
385 + unsigned long flags;
386 + unsigned long pos;
387 +
388 + pages = (size + PAGE_SIZE - 1)/PAGE_SIZE;
389 + pos = (buf - pool->virt_addr)/PAGE_SIZE;
390 +
391 + BUG_ON((buf - pool->virt_addr) & (PAGE_SIZE - 1));
392 +
393 + spin_lock_irqsave(&pool->lock, flags);
394 + bitmap_clear(pool->alloc_map, pos, pages);
395 + pool->num_pages -= pages;
396 + if (pool->num_pages == 0)
397 + pool->alloc_pos = 0;
398 + DO_STATS(pool->num_bufs--);
399 + spin_unlock_irqrestore(&pool->lock, flags);
400 +}
401 +
402 +/* allocate a 'safe' buffer and keep track of it */
403 +static struct safe_buffer *
404 +alloc_safe_buffer(struct dmabounce_device_info *device_info,
405 + dma_addr_t dma_addr, size_t size, enum dma_data_direction dir)
406 +{
407 + struct safe_buffer *buf;
408 + struct dmabounce_pool *pool = &device_info->pool;
409 + struct device *dev = device_info->dev;
410 + unsigned long flags;
411 +
412 + /*
413 + * Although one might expect this to be called in thread context,
414 + * using GFP_KERNEL here leads to hard-to-debug lockups. in_atomic()
415 + * was previously used to select the appropriate allocation mode,
416 + * but this is unsafe.
417 + */
418 + buf = kmalloc(sizeof(struct safe_buffer), GFP_ATOMIC);
419 + if (!buf) {
420 + dev_warn(dev, "%s: kmalloc failed\n", __func__);
421 + return NULL;
422 + }
423 +
424 + buf->unsafe_dma_addr = dma_addr;
425 + buf->size = size;
426 + buf->direction = dir;
427 + buf->pool = pool;
428 +
429 + buf->safe = bounce_alloc(pool, size, &buf->safe_dma_addr);
430 +
431 + if (!buf->safe) {
432 + dev_warn(dev,
433 + "%s: could not alloc dma memory (size=%d)\n",
434 + __func__, size);
435 + kfree(buf);
436 + return NULL;
437 + }
438 +
439 + write_lock_irqsave(&device_info->lock, flags);
440 + list_add(&buf->node, &device_info->safe_buffers);
441 + write_unlock_irqrestore(&device_info->lock, flags);
442 +
443 + return buf;
444 +}
445 +
446 +/* determine if a buffer is from our "safe" pool */
447 +static struct safe_buffer *
448 +find_safe_buffer(struct dmabounce_device_info *device_info,
449 + dma_addr_t safe_dma_addr)
450 +{
451 + struct safe_buffer *b, *rb = NULL;
452 + unsigned long flags;
453 +
454 + read_lock_irqsave(&device_info->lock, flags);
455 +
456 + list_for_each_entry(b, &device_info->safe_buffers, node)
457 + if (b->safe_dma_addr <= safe_dma_addr &&
458 + b->safe_dma_addr + b->size > safe_dma_addr) {
459 + rb = b;
460 + break;
461 + }
462 +
463 + read_unlock_irqrestore(&device_info->lock, flags);
464 + return rb;
465 +}
466 +
467 +static void
468 +free_safe_buffer(struct dmabounce_device_info *device_info,
469 + struct safe_buffer *buf)
470 +{
471 + unsigned long flags;
472 +
473 + write_lock_irqsave(&device_info->lock, flags);
474 + list_del(&buf->node);
475 + write_unlock_irqrestore(&device_info->lock, flags);
476 +
477 + bounce_free(buf->pool, buf->safe, buf->size);
478 +
479 + kfree(buf);
480 +}
481 +
482 +/* ************************************************** */
483 +
484 +static struct safe_buffer *
485 +find_safe_buffer_dev(struct device *dev, dma_addr_t dma_addr, const char *where)
486 +{
487 + if (!dev || !g_dmabounce_device_info)
488 + return NULL;
489 + if (dma_mapping_error(dev, dma_addr)) {
490 + dev_err(dev, "Trying to %s invalid mapping\n", where);
491 + return NULL;
492 + }
493 + return find_safe_buffer(g_dmabounce_device_info, dma_addr);
494 +}
495 +
496 +static dma_addr_t
497 +map_single(struct device *dev, struct safe_buffer *buf, size_t size,
498 + enum dma_data_direction dir, unsigned long attrs)
499 +{
500 + BUG_ON(buf->size != size);
501 + BUG_ON(buf->direction != dir);
502 +
503 + dev_dbg(dev, "map: %llx->%llx\n", (u64)buf->unsafe_dma_addr,
504 + (u64)buf->safe_dma_addr);
505 +
506 + if ((dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) &&
507 + !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
508 + bcm2838_dma40_memcpy(buf->safe_dma_addr, buf->unsafe_dma_addr,
509 + size);
510 +
511 + return buf->safe_dma_addr;
512 +}
513 +
514 +static dma_addr_t
515 +unmap_single(struct device *dev, struct safe_buffer *buf, size_t size,
516 + enum dma_data_direction dir, unsigned long attrs)
517 +{
518 + BUG_ON(buf->size != size);
519 + BUG_ON(buf->direction != dir);
520 +
521 + if ((dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) &&
522 + !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {
523 + dev_dbg(dev, "unmap: %llx->%llx\n", (u64)buf->safe_dma_addr,
524 + (u64)buf->unsafe_dma_addr);
525 +
526 + bcm2838_dma40_memcpy(buf->unsafe_dma_addr, buf->safe_dma_addr,
527 + size);
528 + }
529 + return buf->unsafe_dma_addr;
530 +}
531 +
532 +/* ************************************************** */
533 +
534 +/*
535 + * see if a buffer address is in an 'unsafe' range. if it is
536 + * allocate a 'safe' buffer and copy the unsafe buffer into it.
537 + * substitute the safe buffer for the unsafe one.
538 + * (basically move the buffer from an unsafe area to a safe one)
539 + */
540 +static dma_addr_t
541 +dmabounce_map_page(struct device *dev, struct page *page, unsigned long offset,
542 + size_t size, enum dma_data_direction dir,
543 + unsigned long attrs)
544 +{
545 + struct dmabounce_device_info *device_info = g_dmabounce_device_info;
546 + dma_addr_t dma_addr;
547 +
548 + dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset;
549 +
550 + swiotlb_sync_single_for_device(dev, dma_addr, size, dir);
551 + if (!is_device_dma_coherent(dev))
552 + __dma_map_area(phys_to_virt(dma_to_phys(dev, dma_addr)), size, dir);
553 +
554 + if (device_info && (dma_addr + size) > device_info->threshold) {
555 + struct safe_buffer *buf;
556 +
557 + buf = alloc_safe_buffer(device_info, dma_addr, size, dir);
558 + if (!buf) {
559 + DO_STATS(device_info->fail_count++);
560 + return (~(dma_addr_t)0x0);
561 + }
562 +
563 + DO_STATS(device_info->map_count++);
564 +
565 + dma_addr = map_single(dev, buf, size, dir, attrs);
566 + }
567 + return dma_addr;
568 +}
569 +
570 +/*
571 + * see if a mapped address was really a "safe" buffer and if so, copy
572 + * the data from the safe buffer back to the unsafe buffer and free up
573 + * the safe buffer. (basically return things back to the way they
574 + * should be)
575 + */
576 +static void
577 +dmabounce_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
578 + enum dma_data_direction dir, unsigned long attrs)
579 +{
580 + struct safe_buffer *buf;
581 +
582 + buf = find_safe_buffer_dev(dev, dma_addr, __func__);
583 + if (buf) {
584 + DO_STATS(g_dmabounce_device_info->unmap_count++);
585 + dma_addr = unmap_single(dev, buf, size, dir, attrs);
586 + free_safe_buffer(g_dmabounce_device_info, buf);
587 + }
588 +
589 + if (!is_device_dma_coherent(dev))
590 + __dma_unmap_area(phys_to_virt(dma_to_phys(dev, dma_addr)), size, dir);
591 + swiotlb_sync_single_for_cpu(dev, dma_addr, size, dir);
592 +}
593 +
594 +/*
595 + * A version of dmabounce_map_page that assumes the mapping has already
596 + * been created - intended for streaming operation.
597 + */
598 +static void
599 +dmabounce_sync_for_device(struct device *dev, dma_addr_t dma_addr, size_t size,
600 + enum dma_data_direction dir)
601 +{
602 + struct safe_buffer *buf;
603 +
604 + swiotlb_sync_single_for_device(dev, dma_addr, size, dir);
605 + if (!is_device_dma_coherent(dev))
606 + __dma_map_area(phys_to_virt(dma_to_phys(dev, dma_addr)), size, dir);
607 +
608 + buf = find_safe_buffer_dev(dev, dma_addr, __func__);
609 + if (buf) {
610 + DO_STATS(g_dmabounce_device_info->sync_dev_count++);
611 + map_single(dev, buf, size, dir, 0);
612 + }
613 +}
614 +
615 +/*
616 + * A version of dmabounce_unmap_page that doesn't destroy the mapping -
617 + * intended for streaming operation.
618 + */
619 +static void
620 +dmabounce_sync_for_cpu(struct device *dev, dma_addr_t dma_addr,
621 + size_t size, enum dma_data_direction dir)
622 +{
623 + struct safe_buffer *buf;
624 +
625 + buf = find_safe_buffer_dev(dev, dma_addr, __func__);
626 + if (buf) {
627 + DO_STATS(g_dmabounce_device_info->sync_cpu_count++);
628 + dma_addr = unmap_single(dev, buf, size, dir, 0);
629 + }
630 +
631 + if (!is_device_dma_coherent(dev))
632 + __dma_unmap_area(phys_to_virt(dma_to_phys(dev, dma_addr)), size, dir);
633 + swiotlb_sync_single_for_cpu(dev, dma_addr, size, dir);
634 +}
635 +
636 +static int dmabounce_dma_supported(struct device *dev, u64 dma_mask)
637 +{
638 + if (g_dmabounce_device_info)
639 + return 0;
640 +
641 + return swiotlb_dma_supported(dev, dma_mask);
642 +}
643 +
644 +static int dmabounce_mapping_error(struct device *dev, dma_addr_t dma_addr)
645 +{
646 + return swiotlb_dma_mapping_error(dev, dma_addr);
647 +}
648 +
649 +static const struct dma_map_ops dmabounce_ops = {
650 + .alloc = arm64_dma_alloc,
651 + .free = arm64_dma_free,
652 + .mmap = arm64_dma_mmap,
653 + .get_sgtable = arm64_dma_get_sgtable,
654 + .map_page = dmabounce_map_page,
655 + .unmap_page = dmabounce_unmap_page,
656 + .sync_single_for_cpu = dmabounce_sync_for_cpu,
657 + .sync_single_for_device = dmabounce_sync_for_device,
658 + .map_sg = arm64_dma_map_sg,
659 + .unmap_sg = arm64_dma_unmap_sg,
660 + .sync_sg_for_cpu = arm64_dma_sync_sg_for_cpu,
661 + .sync_sg_for_device = arm64_dma_sync_sg_for_device,
662 + .dma_supported = dmabounce_dma_supported,
663 + .mapping_error = dmabounce_mapping_error,
664 +};
665 +
666 +int brcm_pcie_bounce_init(struct device *dev,
667 + unsigned long buffer_size,
668 + dma_addr_t threshold)
669 +{
670 + struct dmabounce_device_info *device_info;
671 + int ret;
672 +
673 + /* Only support a single client */
674 + if (g_dmabounce_device_info)
675 + return -EBUSY;
676 +
677 + ret = bcm2838_dma40_memcpy_init();
678 + if (ret)
679 + return ret;
680 +
681 + device_info = kmalloc(sizeof(struct dmabounce_device_info), GFP_ATOMIC);
682 + if (!device_info) {
683 + dev_err(dev,
684 + "Could not allocated dmabounce_device_info\n");
685 + return -ENOMEM;
686 + }
687 +
688 + ret = bounce_create(&device_info->pool, dev, buffer_size);
689 + if (ret) {
690 + dev_err(dev,
691 + "dmabounce: could not allocate %ld byte DMA pool\n",
692 + buffer_size);
693 + goto err_bounce;
694 + }
695 +
696 + device_info->dev = dev;
697 + device_info->threshold = threshold;
698 + INIT_LIST_HEAD(&device_info->safe_buffers);
699 + rwlock_init(&device_info->lock);
700 +
701 + DO_STATS(device_info->map_count = 0);
702 + DO_STATS(device_info->unmap_count = 0);
703 + DO_STATS(device_info->sync_dev_count = 0);
704 + DO_STATS(device_info->sync_cpu_count = 0);
705 + DO_STATS(device_info->fail_count = 0);
706 + DO_STATS(device_info->attr_res =
707 + device_create_file(dev, &dev_attr_dmabounce_stats));
708 +
709 + g_dmabounce_device_info = device_info;
710 +
711 + dev_err(dev, "dmabounce: initialised - %ld kB, threshold %pad\n",
712 + buffer_size / 1024, &threshold);
713 +
714 + return 0;
715 +
716 + err_bounce:
717 + kfree(device_info);
718 + return ret;
719 +}
720 +EXPORT_SYMBOL(brcm_pcie_bounce_init);
721 +
722 +void brcm_pcie_bounce_uninit(struct device *dev)
723 +{
724 + struct dmabounce_device_info *device_info = g_dmabounce_device_info;
725 +
726 + g_dmabounce_device_info = NULL;
727 +
728 + if (!device_info) {
729 + dev_warn(dev,
730 + "Never registered with dmabounce but attempting"
731 + "to unregister!\n");
732 + return;
733 + }
734 +
735 + if (!list_empty(&device_info->safe_buffers)) {
736 + dev_err(dev,
737 + "Removing from dmabounce with pending buffers!\n");
738 + BUG();
739 + }
740 +
741 + bounce_destroy(&device_info->pool);
742 +
743 + DO_STATS(if (device_info->attr_res == 0)
744 + device_remove_file(dev, &dev_attr_dmabounce_stats));
745 +
746 + kfree(device_info);
747 +}
748 +EXPORT_SYMBOL(brcm_pcie_bounce_uninit);
749 +
750 +int brcm_pcie_bounce_register_dev(struct device *dev)
751 +{
752 + set_dma_ops(dev, &dmabounce_ops);
753 +
754 + return 0;
755 +}
756 +EXPORT_SYMBOL(brcm_pcie_bounce_register_dev);
757 +
758 +MODULE_AUTHOR("Phil Elwell <phil@raspberrypi.org>");
759 +MODULE_DESCRIPTION("Dedicate DMA bounce support for pcie-brcmstb");
760 +MODULE_LICENSE("GPL");
761 --- a/drivers/pci/controller/pcie-brcmstb.c
762 +++ b/drivers/pci/controller/pcie-brcmstb.c
763 @@ -617,28 +617,6 @@ static const struct dma_map_ops brcm_dma
764
765 static void brcm_set_dma_ops(struct device *dev)
766 {
767 - int ret;
768 -
769 - if (IS_ENABLED(CONFIG_ARM64)) {
770 - /*
771 - * We are going to invoke get_dma_ops(). That
772 - * function, at this point in time, invokes
773 - * get_arch_dma_ops(), and for ARM64 that function
774 - * returns a pointer to dummy_dma_ops. So then we'd
775 - * like to call arch_setup_dma_ops(), but that isn't
776 - * exported. Instead, we call of_dma_configure(),
777 - * which is exported, and this calls
778 - * arch_setup_dma_ops(). Once we do this the call to
779 - * get_dma_ops() will work properly because
780 - * dev->dma_ops will be set.
781 - */
782 - ret = of_dma_configure(dev, dev->of_node, true);
783 - if (ret) {
784 - dev_err(dev, "of_dma_configure() failed: %d\n", ret);
785 - return;
786 - }
787 - }
788 -
789 arch_dma_ops = get_dma_ops(dev);
790 if (!arch_dma_ops) {
791 dev_err(dev, "failed to get arch_dma_ops\n");
792 @@ -657,12 +635,12 @@ static int brcmstb_platform_notifier(str
793 extern unsigned long max_pfn;
794 struct device *dev = __dev;
795 const char *rc_name = "0000:00:00.0";
796 + int ret;
797
798 switch (event) {
799 case BUS_NOTIFY_ADD_DEVICE:
800 if (max_pfn > (bounce_threshold/PAGE_SIZE) &&
801 strcmp(dev->kobj.name, rc_name)) {
802 - int ret;
803
804 ret = brcm_pcie_bounce_register_dev(dev);
805 if (ret) {
806 @@ -671,6 +649,12 @@ static int brcmstb_platform_notifier(str
807 ret);
808 return ret;
809 }
810 + } else if (IS_ENABLED(CONFIG_ARM64)) {
811 + ret = of_dma_configure(dev, dev->of_node, true);
812 + if (ret) {
813 + dev_err(dev, "of_dma_configure() failed: %d\n", ret);
814 + return;
815 + }
816 }
817 brcm_set_dma_ops(dev);
818 return NOTIFY_OK;
OpenWrt Source Repository