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-rw-r--r--arch/arm/mach-bcmring/dma.c2321
1 files changed, 2321 insertions, 0 deletions
diff --git a/arch/arm/mach-bcmring/dma.c b/arch/arm/mach-bcmring/dma.c
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index 000000000000..7b20fccb9d4e
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1/*****************************************************************************
2* Copyright 2004 - 2008 Broadcom Corporation. All rights reserved.
3*
4* Unless you and Broadcom execute a separate written software license
5* agreement governing use of this software, this software is licensed to you
6* under the terms of the GNU General Public License version 2, available at
7* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
8*
9* Notwithstanding the above, under no circumstances may you combine this
10* software in any way with any other Broadcom software provided under a
11* license other than the GPL, without Broadcom's express prior written
12* consent.
13*****************************************************************************/
14
15/****************************************************************************/
16/**
17* @file dma.c
18*
19* @brief Implements the DMA interface.
20*/
21/****************************************************************************/
22
23/* ---- Include Files ---------------------------------------------------- */
24
25#include <linux/module.h>
26#include <linux/device.h>
27#include <linux/dma-mapping.h>
28#include <linux/interrupt.h>
29#include <linux/irqreturn.h>
30#include <linux/proc_fs.h>
31
32#include <mach/timer.h>
33
34#include <linux/mm.h>
35#include <linux/pfn.h>
36#include <asm/atomic.h>
37#include <mach/dma.h>
38
39/* I don't quite understand why dc4 fails when this is set to 1 and DMA is enabled */
40/* especially since dc4 doesn't use kmalloc'd memory. */
41
42#define ALLOW_MAP_OF_KMALLOC_MEMORY 0
43
44/* ---- Public Variables ------------------------------------------------- */
45
46/* ---- Private Constants and Types -------------------------------------- */
47
48#define MAKE_HANDLE(controllerIdx, channelIdx) (((controllerIdx) << 4) | (channelIdx))
49
50#define CONTROLLER_FROM_HANDLE(handle) (((handle) >> 4) & 0x0f)
51#define CHANNEL_FROM_HANDLE(handle) ((handle) & 0x0f)
52
53#define DMA_MAP_DEBUG 0
54
55#if DMA_MAP_DEBUG
56# define DMA_MAP_PRINT(fmt, args...) printk("%s: " fmt, __func__, ## args)
57#else
58# define DMA_MAP_PRINT(fmt, args...)
59#endif
60
61/* ---- Private Variables ------------------------------------------------ */
62
63static DMA_Global_t gDMA;
64static struct proc_dir_entry *gDmaDir;
65
66static atomic_t gDmaStatMemTypeKmalloc = ATOMIC_INIT(0);
67static atomic_t gDmaStatMemTypeVmalloc = ATOMIC_INIT(0);
68static atomic_t gDmaStatMemTypeUser = ATOMIC_INIT(0);
69static atomic_t gDmaStatMemTypeCoherent = ATOMIC_INIT(0);
70
71#include "dma_device.c"
72
73/* ---- Private Function Prototypes -------------------------------------- */
74
75/* ---- Functions ------------------------------------------------------- */
76
77/****************************************************************************/
78/**
79* Displays information for /proc/dma/mem-type
80*/
81/****************************************************************************/
82
83static int dma_proc_read_mem_type(char *buf, char **start, off_t offset,
84 int count, int *eof, void *data)
85{
86 int len = 0;
87
88 len += sprintf(buf + len, "dma_map_mem statistics\n");
89 len +=
90 sprintf(buf + len, "coherent: %d\n",
91 atomic_read(&gDmaStatMemTypeCoherent));
92 len +=
93 sprintf(buf + len, "kmalloc: %d\n",
94 atomic_read(&gDmaStatMemTypeKmalloc));
95 len +=
96 sprintf(buf + len, "vmalloc: %d\n",
97 atomic_read(&gDmaStatMemTypeVmalloc));
98 len +=
99 sprintf(buf + len, "user: %d\n",
100 atomic_read(&gDmaStatMemTypeUser));
101
102 return len;
103}
104
105/****************************************************************************/
106/**
107* Displays information for /proc/dma/channels
108*/
109/****************************************************************************/
110
111static int dma_proc_read_channels(char *buf, char **start, off_t offset,
112 int count, int *eof, void *data)
113{
114 int controllerIdx;
115 int channelIdx;
116 int limit = count - 200;
117 int len = 0;
118 DMA_Channel_t *channel;
119
120 if (down_interruptible(&gDMA.lock) < 0) {
121 return -ERESTARTSYS;
122 }
123
124 for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
125 controllerIdx++) {
126 for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
127 channelIdx++) {
128 if (len >= limit) {
129 break;
130 }
131
132 channel =
133 &gDMA.controller[controllerIdx].channel[channelIdx];
134
135 len +=
136 sprintf(buf + len, "%d:%d ", controllerIdx,
137 channelIdx);
138
139 if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
140 0) {
141 len +=
142 sprintf(buf + len, "Dedicated for %s ",
143 DMA_gDeviceAttribute[channel->
144 devType].name);
145 } else {
146 len += sprintf(buf + len, "Shared ");
147 }
148
149 if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) != 0) {
150 len += sprintf(buf + len, "No ISR ");
151 }
152
153 if ((channel->flags & DMA_CHANNEL_FLAG_LARGE_FIFO) != 0) {
154 len += sprintf(buf + len, "Fifo: 128 ");
155 } else {
156 len += sprintf(buf + len, "Fifo: 64 ");
157 }
158
159 if ((channel->flags & DMA_CHANNEL_FLAG_IN_USE) != 0) {
160 len +=
161 sprintf(buf + len, "InUse by %s",
162 DMA_gDeviceAttribute[channel->
163 devType].name);
164#if (DMA_DEBUG_TRACK_RESERVATION)
165 len +=
166 sprintf(buf + len, " (%s:%d)",
167 channel->fileName,
168 channel->lineNum);
169#endif
170 } else {
171 len += sprintf(buf + len, "Avail ");
172 }
173
174 if (channel->lastDevType != DMA_DEVICE_NONE) {
175 len +=
176 sprintf(buf + len, "Last use: %s ",
177 DMA_gDeviceAttribute[channel->
178 lastDevType].
179 name);
180 }
181
182 len += sprintf(buf + len, "\n");
183 }
184 }
185 up(&gDMA.lock);
186 *eof = 1;
187
188 return len;
189}
190
191/****************************************************************************/
192/**
193* Displays information for /proc/dma/devices
194*/
195/****************************************************************************/
196
197static int dma_proc_read_devices(char *buf, char **start, off_t offset,
198 int count, int *eof, void *data)
199{
200 int limit = count - 200;
201 int len = 0;
202 int devIdx;
203
204 if (down_interruptible(&gDMA.lock) < 0) {
205 return -ERESTARTSYS;
206 }
207
208 for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
209 DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
210
211 if (devAttr->name == NULL) {
212 continue;
213 }
214
215 if (len >= limit) {
216 break;
217 }
218
219 len += sprintf(buf + len, "%-12s ", devAttr->name);
220
221 if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
222 len +=
223 sprintf(buf + len, "Dedicated %d:%d ",
224 devAttr->dedicatedController,
225 devAttr->dedicatedChannel);
226 } else {
227 len += sprintf(buf + len, "Shared DMA:");
228 if ((devAttr->flags & DMA_DEVICE_FLAG_ON_DMA0) != 0) {
229 len += sprintf(buf + len, "0");
230 }
231 if ((devAttr->flags & DMA_DEVICE_FLAG_ON_DMA1) != 0) {
232 len += sprintf(buf + len, "1");
233 }
234 len += sprintf(buf + len, " ");
235 }
236 if ((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0) {
237 len += sprintf(buf + len, "NoISR ");
238 }
239 if ((devAttr->flags & DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO) != 0) {
240 len += sprintf(buf + len, "Allow-128 ");
241 }
242
243 len +=
244 sprintf(buf + len,
245 "Xfer #: %Lu Ticks: %Lu Bytes: %Lu DescLen: %u\n",
246 devAttr->numTransfers, devAttr->transferTicks,
247 devAttr->transferBytes,
248 devAttr->ring.bytesAllocated);
249
250 }
251
252 up(&gDMA.lock);
253 *eof = 1;
254
255 return len;
256}
257
258/****************************************************************************/
259/**
260* Determines if a DMA_Device_t is "valid".
261*
262* @return
263* TRUE - dma device is valid
264* FALSE - dma device isn't valid
265*/
266/****************************************************************************/
267
268static inline int IsDeviceValid(DMA_Device_t device)
269{
270 return (device >= 0) && (device < DMA_NUM_DEVICE_ENTRIES);
271}
272
273/****************************************************************************/
274/**
275* Translates a DMA handle into a pointer to a channel.
276*
277* @return
278* non-NULL - pointer to DMA_Channel_t
279* NULL - DMA Handle was invalid
280*/
281/****************************************************************************/
282
283static inline DMA_Channel_t *HandleToChannel(DMA_Handle_t handle)
284{
285 int controllerIdx;
286 int channelIdx;
287
288 controllerIdx = CONTROLLER_FROM_HANDLE(handle);
289 channelIdx = CHANNEL_FROM_HANDLE(handle);
290
291 if ((controllerIdx > DMA_NUM_CONTROLLERS)
292 || (channelIdx > DMA_NUM_CHANNELS)) {
293 return NULL;
294 }
295 return &gDMA.controller[controllerIdx].channel[channelIdx];
296}
297
298/****************************************************************************/
299/**
300* Interrupt handler which is called to process DMA interrupts.
301*/
302/****************************************************************************/
303
304static irqreturn_t dma_interrupt_handler(int irq, void *dev_id)
305{
306 DMA_Channel_t *channel;
307 DMA_DeviceAttribute_t *devAttr;
308 int irqStatus;
309
310 channel = (DMA_Channel_t *) dev_id;
311
312 /* Figure out why we were called, and knock down the interrupt */
313
314 irqStatus = dmacHw_getInterruptStatus(channel->dmacHwHandle);
315 dmacHw_clearInterrupt(channel->dmacHwHandle);
316
317 if ((channel->devType < 0)
318 || (channel->devType > DMA_NUM_DEVICE_ENTRIES)) {
319 printk(KERN_ERR "dma_interrupt_handler: Invalid devType: %d\n",
320 channel->devType);
321 return IRQ_NONE;
322 }
323 devAttr = &DMA_gDeviceAttribute[channel->devType];
324
325 /* Update stats */
326
327 if ((irqStatus & dmacHw_INTERRUPT_STATUS_TRANS) != 0) {
328 devAttr->transferTicks +=
329 (timer_get_tick_count() - devAttr->transferStartTime);
330 }
331
332 if ((irqStatus & dmacHw_INTERRUPT_STATUS_ERROR) != 0) {
333 printk(KERN_ERR
334 "dma_interrupt_handler: devType :%d DMA error (%s)\n",
335 channel->devType, devAttr->name);
336 } else {
337 devAttr->numTransfers++;
338 devAttr->transferBytes += devAttr->numBytes;
339 }
340
341 /* Call any installed handler */
342
343 if (devAttr->devHandler != NULL) {
344 devAttr->devHandler(channel->devType, irqStatus,
345 devAttr->userData);
346 }
347
348 return IRQ_HANDLED;
349}
350
351/****************************************************************************/
352/**
353* Allocates memory to hold a descriptor ring. The descriptor ring then
354* needs to be populated by making one or more calls to
355* dna_add_descriptors.
356*
357* The returned descriptor ring will be automatically initialized.
358*
359* @return
360* 0 Descriptor ring was allocated successfully
361* -EINVAL Invalid parameters passed in
362* -ENOMEM Unable to allocate memory for the desired number of descriptors.
363*/
364/****************************************************************************/
365
366int dma_alloc_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to populate */
367 int numDescriptors /* Number of descriptors that need to be allocated. */
368 ) {
369 size_t bytesToAlloc = dmacHw_descriptorLen(numDescriptors);
370
371 if ((ring == NULL) || (numDescriptors <= 0)) {
372 return -EINVAL;
373 }
374
375 ring->physAddr = 0;
376 ring->descriptorsAllocated = 0;
377 ring->bytesAllocated = 0;
378
379 ring->virtAddr = dma_alloc_writecombine(NULL,
380 bytesToAlloc,
381 &ring->physAddr,
382 GFP_KERNEL);
383 if (ring->virtAddr == NULL) {
384 return -ENOMEM;
385 }
386
387 ring->bytesAllocated = bytesToAlloc;
388 ring->descriptorsAllocated = numDescriptors;
389
390 return dma_init_descriptor_ring(ring, numDescriptors);
391}
392
393EXPORT_SYMBOL(dma_alloc_descriptor_ring);
394
395/****************************************************************************/
396/**
397* Releases the memory which was previously allocated for a descriptor ring.
398*/
399/****************************************************************************/
400
401void dma_free_descriptor_ring(DMA_DescriptorRing_t *ring /* Descriptor to release */
402 ) {
403 if (ring->virtAddr != NULL) {
404 dma_free_writecombine(NULL,
405 ring->bytesAllocated,
406 ring->virtAddr, ring->physAddr);
407 }
408
409 ring->bytesAllocated = 0;
410 ring->descriptorsAllocated = 0;
411 ring->virtAddr = NULL;
412 ring->physAddr = 0;
413}
414
415EXPORT_SYMBOL(dma_free_descriptor_ring);
416
417/****************************************************************************/
418/**
419* Initializes a descriptor ring, so that descriptors can be added to it.
420* Once a descriptor ring has been allocated, it may be reinitialized for
421* use with additional/different regions of memory.
422*
423* Note that if 7 descriptors are allocated, it's perfectly acceptable to
424* initialize the ring with a smaller number of descriptors. The amount
425* of memory allocated for the descriptor ring will not be reduced, and
426* the descriptor ring may be reinitialized later
427*
428* @return
429* 0 Descriptor ring was initialized successfully
430* -ENOMEM The descriptor which was passed in has insufficient space
431* to hold the desired number of descriptors.
432*/
433/****************************************************************************/
434
435int dma_init_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to initialize */
436 int numDescriptors /* Number of descriptors to initialize. */
437 ) {
438 if (ring->virtAddr == NULL) {
439 return -EINVAL;
440 }
441 if (dmacHw_initDescriptor(ring->virtAddr,
442 ring->physAddr,
443 ring->bytesAllocated, numDescriptors) < 0) {
444 printk(KERN_ERR
445 "dma_init_descriptor_ring: dmacHw_initDescriptor failed\n");
446 return -ENOMEM;
447 }
448
449 return 0;
450}
451
452EXPORT_SYMBOL(dma_init_descriptor_ring);
453
454/****************************************************************************/
455/**
456* Determines the number of descriptors which would be required for a
457* transfer of the indicated memory region.
458*
459* This function also needs to know which DMA device this transfer will
460* be destined for, so that the appropriate DMA configuration can be retrieved.
461* DMA parameters such as transfer width, and whether this is a memory-to-memory
462* or memory-to-peripheral, etc can all affect the actual number of descriptors
463* required.
464*
465* @return
466* > 0 Returns the number of descriptors required for the indicated transfer
467* -ENODEV - Device handed in is invalid.
468* -EINVAL Invalid parameters
469* -ENOMEM Memory exhausted
470*/
471/****************************************************************************/
472
473int dma_calculate_descriptor_count(DMA_Device_t device, /* DMA Device that this will be associated with */
474 dma_addr_t srcData, /* Place to get data to write to device */
475 dma_addr_t dstData, /* Pointer to device data address */
476 size_t numBytes /* Number of bytes to transfer to the device */
477 ) {
478 int numDescriptors;
479 DMA_DeviceAttribute_t *devAttr;
480
481 if (!IsDeviceValid(device)) {
482 return -ENODEV;
483 }
484 devAttr = &DMA_gDeviceAttribute[device];
485
486 numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
487 (void *)srcData,
488 (void *)dstData,
489 numBytes);
490 if (numDescriptors < 0) {
491 printk(KERN_ERR
492 "dma_calculate_descriptor_count: dmacHw_calculateDescriptorCount failed\n");
493 return -EINVAL;
494 }
495
496 return numDescriptors;
497}
498
499EXPORT_SYMBOL(dma_calculate_descriptor_count);
500
501/****************************************************************************/
502/**
503* Adds a region of memory to the descriptor ring. Note that it may take
504* multiple descriptors for each region of memory. It is the callers
505* responsibility to allocate a sufficiently large descriptor ring.
506*
507* @return
508* 0 Descriptors were added successfully
509* -ENODEV Device handed in is invalid.
510* -EINVAL Invalid parameters
511* -ENOMEM Memory exhausted
512*/
513/****************************************************************************/
514
515int dma_add_descriptors(DMA_DescriptorRing_t *ring, /* Descriptor ring to add descriptors to */
516 DMA_Device_t device, /* DMA Device that descriptors are for */
517 dma_addr_t srcData, /* Place to get data (memory or device) */
518 dma_addr_t dstData, /* Place to put data (memory or device) */
519 size_t numBytes /* Number of bytes to transfer to the device */
520 ) {
521 int rc;
522 DMA_DeviceAttribute_t *devAttr;
523
524 if (!IsDeviceValid(device)) {
525 return -ENODEV;
526 }
527 devAttr = &DMA_gDeviceAttribute[device];
528
529 rc = dmacHw_setDataDescriptor(&devAttr->config,
530 ring->virtAddr,
531 (void *)srcData,
532 (void *)dstData, numBytes);
533 if (rc < 0) {
534 printk(KERN_ERR
535 "dma_add_descriptors: dmacHw_setDataDescriptor failed with code: %d\n",
536 rc);
537 return -ENOMEM;
538 }
539
540 return 0;
541}
542
543EXPORT_SYMBOL(dma_add_descriptors);
544
545/****************************************************************************/
546/**
547* Sets the descriptor ring associated with a device.
548*
549* Once set, the descriptor ring will be associated with the device, even
550* across channel request/free calls. Passing in a NULL descriptor ring
551* will release any descriptor ring currently associated with the device.
552*
553* Note: If you call dma_transfer, or one of the other dma_alloc_ functions
554* the descriptor ring may be released and reallocated.
555*
556* Note: This function will release the descriptor memory for any current
557* descriptor ring associated with this device.
558*
559* @return
560* 0 Descriptors were added successfully
561* -ENODEV Device handed in is invalid.
562*/
563/****************************************************************************/
564
565int dma_set_device_descriptor_ring(DMA_Device_t device, /* Device to update the descriptor ring for. */
566 DMA_DescriptorRing_t *ring /* Descriptor ring to add descriptors to */
567 ) {
568 DMA_DeviceAttribute_t *devAttr;
569
570 if (!IsDeviceValid(device)) {
571 return -ENODEV;
572 }
573 devAttr = &DMA_gDeviceAttribute[device];
574
575 /* Free the previously allocated descriptor ring */
576
577 dma_free_descriptor_ring(&devAttr->ring);
578
579 if (ring != NULL) {
580 /* Copy in the new one */
581
582 devAttr->ring = *ring;
583 }
584
585 /* Set things up so that if dma_transfer is called then this descriptor */
586 /* ring will get freed. */
587
588 devAttr->prevSrcData = 0;
589 devAttr->prevDstData = 0;
590 devAttr->prevNumBytes = 0;
591
592 return 0;
593}
594
595EXPORT_SYMBOL(dma_set_device_descriptor_ring);
596
597/****************************************************************************/
598/**
599* Retrieves the descriptor ring associated with a device.
600*
601* @return
602* 0 Descriptors were added successfully
603* -ENODEV Device handed in is invalid.
604*/
605/****************************************************************************/
606
607int dma_get_device_descriptor_ring(DMA_Device_t device, /* Device to retrieve the descriptor ring for. */
608 DMA_DescriptorRing_t *ring /* Place to store retrieved ring */
609 ) {
610 DMA_DeviceAttribute_t *devAttr;
611
612 memset(ring, 0, sizeof(*ring));
613
614 if (!IsDeviceValid(device)) {
615 return -ENODEV;
616 }
617 devAttr = &DMA_gDeviceAttribute[device];
618
619 *ring = devAttr->ring;
620
621 return 0;
622}
623
624EXPORT_SYMBOL(dma_get_device_descriptor_ring);
625
626/****************************************************************************/
627/**
628* Configures a DMA channel.
629*
630* @return
631* >= 0 - Initialization was successfull.
632*
633* -EBUSY - Device is currently being used.
634* -ENODEV - Device handed in is invalid.
635*/
636/****************************************************************************/
637
638static int ConfigChannel(DMA_Handle_t handle)
639{
640 DMA_Channel_t *channel;
641 DMA_DeviceAttribute_t *devAttr;
642 int controllerIdx;
643
644 channel = HandleToChannel(handle);
645 if (channel == NULL) {
646 return -ENODEV;
647 }
648 devAttr = &DMA_gDeviceAttribute[channel->devType];
649 controllerIdx = CONTROLLER_FROM_HANDLE(handle);
650
651 if ((devAttr->flags & DMA_DEVICE_FLAG_PORT_PER_DMAC) != 0) {
652 if (devAttr->config.transferType ==
653 dmacHw_TRANSFER_TYPE_MEM_TO_PERIPHERAL) {
654 devAttr->config.dstPeripheralPort =
655 devAttr->dmacPort[controllerIdx];
656 } else if (devAttr->config.transferType ==
657 dmacHw_TRANSFER_TYPE_PERIPHERAL_TO_MEM) {
658 devAttr->config.srcPeripheralPort =
659 devAttr->dmacPort[controllerIdx];
660 }
661 }
662
663 if (dmacHw_configChannel(channel->dmacHwHandle, &devAttr->config) != 0) {
664 printk(KERN_ERR "ConfigChannel: dmacHw_configChannel failed\n");
665 return -EIO;
666 }
667
668 return 0;
669}
670
671/****************************************************************************/
672/**
673* Intializes all of the data structures associated with the DMA.
674* @return
675* >= 0 - Initialization was successfull.
676*
677* -EBUSY - Device is currently being used.
678* -ENODEV - Device handed in is invalid.
679*/
680/****************************************************************************/
681
682int dma_init(void)
683{
684 int rc = 0;
685 int controllerIdx;
686 int channelIdx;
687 DMA_Device_t devIdx;
688 DMA_Channel_t *channel;
689 DMA_Handle_t dedicatedHandle;
690
691 memset(&gDMA, 0, sizeof(gDMA));
692
693 init_MUTEX_LOCKED(&gDMA.lock);
694 init_waitqueue_head(&gDMA.freeChannelQ);
695
696 /* Initialize the Hardware */
697
698 dmacHw_initDma();
699
700 /* Start off by marking all of the DMA channels as shared. */
701
702 for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
703 controllerIdx++) {
704 for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
705 channelIdx++) {
706 channel =
707 &gDMA.controller[controllerIdx].channel[channelIdx];
708
709 channel->flags = 0;
710 channel->devType = DMA_DEVICE_NONE;
711 channel->lastDevType = DMA_DEVICE_NONE;
712
713#if (DMA_DEBUG_TRACK_RESERVATION)
714 channel->fileName = "";
715 channel->lineNum = 0;
716#endif
717
718 channel->dmacHwHandle =
719 dmacHw_getChannelHandle(dmacHw_MAKE_CHANNEL_ID
720 (controllerIdx,
721 channelIdx));
722 dmacHw_initChannel(channel->dmacHwHandle);
723 }
724 }
725
726 /* Record any special attributes that channels may have */
727
728 gDMA.controller[0].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
729 gDMA.controller[0].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
730 gDMA.controller[1].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
731 gDMA.controller[1].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
732
733 /* Now walk through and record the dedicated channels. */
734
735 for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
736 DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
737
738 if (((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0)
739 && ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0)) {
740 printk(KERN_ERR
741 "DMA Device: %s Can only request NO_ISR for dedicated devices\n",
742 devAttr->name);
743 rc = -EINVAL;
744 goto out;
745 }
746
747 if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
748 /* This is a dedicated device. Mark the channel as being reserved. */
749
750 if (devAttr->dedicatedController >= DMA_NUM_CONTROLLERS) {
751 printk(KERN_ERR
752 "DMA Device: %s DMA Controller %d is out of range\n",
753 devAttr->name,
754 devAttr->dedicatedController);
755 rc = -EINVAL;
756 goto out;
757 }
758
759 if (devAttr->dedicatedChannel >= DMA_NUM_CHANNELS) {
760 printk(KERN_ERR
761 "DMA Device: %s DMA Channel %d is out of range\n",
762 devAttr->name,
763 devAttr->dedicatedChannel);
764 rc = -EINVAL;
765 goto out;
766 }
767
768 dedicatedHandle =
769 MAKE_HANDLE(devAttr->dedicatedController,
770 devAttr->dedicatedChannel);
771 channel = HandleToChannel(dedicatedHandle);
772
773 if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
774 0) {
775 printk
776 ("DMA Device: %s attempting to use same DMA Controller:Channel (%d:%d) as %s\n",
777 devAttr->name,
778 devAttr->dedicatedController,
779 devAttr->dedicatedChannel,
780 DMA_gDeviceAttribute[channel->devType].
781 name);
782 rc = -EBUSY;
783 goto out;
784 }
785
786 channel->flags |= DMA_CHANNEL_FLAG_IS_DEDICATED;
787 channel->devType = devIdx;
788
789 if (devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) {
790 channel->flags |= DMA_CHANNEL_FLAG_NO_ISR;
791 }
792
793 /* For dedicated channels, we can go ahead and configure the DMA channel now */
794 /* as well. */
795
796 ConfigChannel(dedicatedHandle);
797 }
798 }
799
800 /* Go through and register the interrupt handlers */
801
802 for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
803 controllerIdx++) {
804 for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
805 channelIdx++) {
806 channel =
807 &gDMA.controller[controllerIdx].channel[channelIdx];
808
809 if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) == 0) {
810 snprintf(channel->name, sizeof(channel->name),
811 "dma %d:%d %s", controllerIdx,
812 channelIdx,
813 channel->devType ==
814 DMA_DEVICE_NONE ? "" :
815 DMA_gDeviceAttribute[channel->devType].
816 name);
817
818 rc =
819 request_irq(IRQ_DMA0C0 +
820 (controllerIdx *
821 DMA_NUM_CHANNELS) +
822 channelIdx,
823 dma_interrupt_handler,
824 IRQF_DISABLED, channel->name,
825 channel);
826 if (rc != 0) {
827 printk(KERN_ERR
828 "request_irq for IRQ_DMA%dC%d failed\n",
829 controllerIdx, channelIdx);
830 }
831 }
832 }
833 }
834
835 /* Create /proc/dma/channels and /proc/dma/devices */
836
837 gDmaDir = create_proc_entry("dma", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
838
839 if (gDmaDir == NULL) {
840 printk(KERN_ERR "Unable to create /proc/dma\n");
841 } else {
842 create_proc_read_entry("channels", 0, gDmaDir,
843 dma_proc_read_channels, NULL);
844 create_proc_read_entry("devices", 0, gDmaDir,
845 dma_proc_read_devices, NULL);
846 create_proc_read_entry("mem-type", 0, gDmaDir,
847 dma_proc_read_mem_type, NULL);
848 }
849
850out:
851
852 up(&gDMA.lock);
853
854 return rc;
855}
856
857/****************************************************************************/
858/**
859* Reserves a channel for use with @a dev. If the device is setup to use
860* a shared channel, then this function will block until a free channel
861* becomes available.
862*
863* @return
864* >= 0 - A valid DMA Handle.
865* -EBUSY - Device is currently being used.
866* -ENODEV - Device handed in is invalid.
867*/
868/****************************************************************************/
869
870#if (DMA_DEBUG_TRACK_RESERVATION)
871DMA_Handle_t dma_request_channel_dbg
872 (DMA_Device_t dev, const char *fileName, int lineNum)
873#else
874DMA_Handle_t dma_request_channel(DMA_Device_t dev)
875#endif
876{
877 DMA_Handle_t handle;
878 DMA_DeviceAttribute_t *devAttr;
879 DMA_Channel_t *channel;
880 int controllerIdx;
881 int controllerIdx2;
882 int channelIdx;
883
884 if (down_interruptible(&gDMA.lock) < 0) {
885 return -ERESTARTSYS;
886 }
887
888 if ((dev < 0) || (dev >= DMA_NUM_DEVICE_ENTRIES)) {
889 handle = -ENODEV;
890 goto out;
891 }
892 devAttr = &DMA_gDeviceAttribute[dev];
893
894#if (DMA_DEBUG_TRACK_RESERVATION)
895 {
896 char *s;
897
898 s = strrchr(fileName, '/');
899 if (s != NULL) {
900 fileName = s + 1;
901 }
902 }
903#endif
904 if ((devAttr->flags & DMA_DEVICE_FLAG_IN_USE) != 0) {
905 /* This device has already been requested and not been freed */
906
907 printk(KERN_ERR "%s: device %s is already requested\n",
908 __func__, devAttr->name);
909 handle = -EBUSY;
910 goto out;
911 }
912
913 if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
914 /* This device has a dedicated channel. */
915
916 channel =
917 &gDMA.controller[devAttr->dedicatedController].
918 channel[devAttr->dedicatedChannel];
919 if ((channel->flags & DMA_CHANNEL_FLAG_IN_USE) != 0) {
920 handle = -EBUSY;
921 goto out;
922 }
923
924 channel->flags |= DMA_CHANNEL_FLAG_IN_USE;
925 devAttr->flags |= DMA_DEVICE_FLAG_IN_USE;
926
927#if (DMA_DEBUG_TRACK_RESERVATION)
928 channel->fileName = fileName;
929 channel->lineNum = lineNum;
930#endif
931 handle =
932 MAKE_HANDLE(devAttr->dedicatedController,
933 devAttr->dedicatedChannel);
934 goto out;
935 }
936
937 /* This device needs to use one of the shared channels. */
938
939 handle = DMA_INVALID_HANDLE;
940 while (handle == DMA_INVALID_HANDLE) {
941 /* Scan through the shared channels and see if one is available */
942
943 for (controllerIdx2 = 0; controllerIdx2 < DMA_NUM_CONTROLLERS;
944 controllerIdx2++) {
945 /* Check to see if we should try on controller 1 first. */
946
947 controllerIdx = controllerIdx2;
948 if ((devAttr->
949 flags & DMA_DEVICE_FLAG_ALLOC_DMA1_FIRST) != 0) {
950 controllerIdx = 1 - controllerIdx;
951 }
952
953 /* See if the device is available on the controller being tested */
954
955 if ((devAttr->
956 flags & (DMA_DEVICE_FLAG_ON_DMA0 << controllerIdx))
957 != 0) {
958 for (channelIdx = 0;
959 channelIdx < DMA_NUM_CHANNELS;
960 channelIdx++) {
961 channel =
962 &gDMA.controller[controllerIdx].
963 channel[channelIdx];
964
965 if (((channel->
966 flags &
967 DMA_CHANNEL_FLAG_IS_DEDICATED) ==
968 0)
969 &&
970 ((channel->
971 flags & DMA_CHANNEL_FLAG_IN_USE)
972 == 0)) {
973 if (((channel->
974 flags &
975 DMA_CHANNEL_FLAG_LARGE_FIFO)
976 != 0)
977 &&
978 ((devAttr->
979 flags &
980 DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO)
981 == 0)) {
982 /* This channel is a large fifo - don't tie it up */
983 /* with devices that we don't want using it. */
984
985 continue;
986 }
987
988 channel->flags |=
989 DMA_CHANNEL_FLAG_IN_USE;
990 channel->devType = dev;
991 devAttr->flags |=
992 DMA_DEVICE_FLAG_IN_USE;
993
994#if (DMA_DEBUG_TRACK_RESERVATION)
995 channel->fileName = fileName;
996 channel->lineNum = lineNum;
997#endif
998 handle =
999 MAKE_HANDLE(controllerIdx,
1000 channelIdx);
1001
1002 /* Now that we've reserved the channel - we can go ahead and configure it */
1003
1004 if (ConfigChannel(handle) != 0) {
1005 handle = -EIO;
1006 printk(KERN_ERR
1007 "dma_request_channel: ConfigChannel failed\n");
1008 }
1009 goto out;
1010 }
1011 }
1012 }
1013 }
1014
1015 /* No channels are currently available. Let's wait for one to free up. */
1016
1017 {
1018 DEFINE_WAIT(wait);
1019
1020 prepare_to_wait(&gDMA.freeChannelQ, &wait,
1021 TASK_INTERRUPTIBLE);
1022 up(&gDMA.lock);
1023 schedule();
1024 finish_wait(&gDMA.freeChannelQ, &wait);
1025
1026 if (signal_pending(current)) {
1027 /* We don't currently hold gDMA.lock, so we return directly */
1028
1029 return -ERESTARTSYS;
1030 }
1031 }
1032
1033 if (down_interruptible(&gDMA.lock)) {
1034 return -ERESTARTSYS;
1035 }
1036 }
1037
1038out:
1039 up(&gDMA.lock);
1040
1041 return handle;
1042}
1043
1044/* Create both _dbg and non _dbg functions for modules. */
1045
1046#if (DMA_DEBUG_TRACK_RESERVATION)
1047#undef dma_request_channel
1048DMA_Handle_t dma_request_channel(DMA_Device_t dev)
1049{
1050 return dma_request_channel_dbg(dev, __FILE__, __LINE__);
1051}
1052
1053EXPORT_SYMBOL(dma_request_channel_dbg);
1054#endif
1055EXPORT_SYMBOL(dma_request_channel);
1056
1057/****************************************************************************/
1058/**
1059* Frees a previously allocated DMA Handle.
1060*/
1061/****************************************************************************/
1062
1063int dma_free_channel(DMA_Handle_t handle /* DMA handle. */
1064 ) {
1065 int rc = 0;
1066 DMA_Channel_t *channel;
1067 DMA_DeviceAttribute_t *devAttr;
1068
1069 if (down_interruptible(&gDMA.lock) < 0) {
1070 return -ERESTARTSYS;
1071 }
1072
1073 channel = HandleToChannel(handle);
1074 if (channel == NULL) {
1075 rc = -EINVAL;
1076 goto out;
1077 }
1078
1079 devAttr = &DMA_gDeviceAttribute[channel->devType];
1080
1081 if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) == 0) {
1082 channel->lastDevType = channel->devType;
1083 channel->devType = DMA_DEVICE_NONE;
1084 }
1085 channel->flags &= ~DMA_CHANNEL_FLAG_IN_USE;
1086 devAttr->flags &= ~DMA_DEVICE_FLAG_IN_USE;
1087
1088out:
1089 up(&gDMA.lock);
1090
1091 wake_up_interruptible(&gDMA.freeChannelQ);
1092
1093 return rc;
1094}
1095
1096EXPORT_SYMBOL(dma_free_channel);
1097
1098/****************************************************************************/
1099/**
1100* Determines if a given device has been configured as using a shared
1101* channel.
1102*
1103* @return
1104* 0 Device uses a dedicated channel
1105* > zero Device uses a shared channel
1106* < zero Error code
1107*/
1108/****************************************************************************/
1109
1110int dma_device_is_channel_shared(DMA_Device_t device /* Device to check. */
1111 ) {
1112 DMA_DeviceAttribute_t *devAttr;
1113
1114 if (!IsDeviceValid(device)) {
1115 return -ENODEV;
1116 }
1117 devAttr = &DMA_gDeviceAttribute[device];
1118
1119 return ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0);
1120}
1121
1122EXPORT_SYMBOL(dma_device_is_channel_shared);
1123
1124/****************************************************************************/
1125/**
1126* Allocates buffers for the descriptors. This is normally done automatically
1127* but needs to be done explicitly when initiating a dma from interrupt
1128* context.
1129*
1130* @return
1131* 0 Descriptors were allocated successfully
1132* -EINVAL Invalid device type for this kind of transfer
1133* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
1134* -ENOMEM Memory exhausted
1135*/
1136/****************************************************************************/
1137
1138int dma_alloc_descriptors(DMA_Handle_t handle, /* DMA Handle */
1139 dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
1140 dma_addr_t srcData, /* Place to get data to write to device */
1141 dma_addr_t dstData, /* Pointer to device data address */
1142 size_t numBytes /* Number of bytes to transfer to the device */
1143 ) {
1144 DMA_Channel_t *channel;
1145 DMA_DeviceAttribute_t *devAttr;
1146 int numDescriptors;
1147 size_t ringBytesRequired;
1148 int rc = 0;
1149
1150 channel = HandleToChannel(handle);
1151 if (channel == NULL) {
1152 return -ENODEV;
1153 }
1154
1155 devAttr = &DMA_gDeviceAttribute[channel->devType];
1156
1157 if (devAttr->config.transferType != transferType) {
1158 return -EINVAL;
1159 }
1160
1161 /* Figure out how many descriptors we need. */
1162
1163 /* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
1164 /* srcData, dstData, numBytes); */
1165
1166 numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
1167 (void *)srcData,
1168 (void *)dstData,
1169 numBytes);
1170 if (numDescriptors < 0) {
1171 printk(KERN_ERR "%s: dmacHw_calculateDescriptorCount failed\n",
1172 __func__);
1173 return -EINVAL;
1174 }
1175
1176 /* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
1177 /* a new one. */
1178
1179 ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
1180
1181 /* printk("ringBytesRequired: %d\n", ringBytesRequired); */
1182
1183 if (ringBytesRequired > devAttr->ring.bytesAllocated) {
1184 /* Make sure that this code path is never taken from interrupt context. */
1185 /* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
1186 /* allocation needs to have already been done. */
1187
1188 might_sleep();
1189
1190 /* Free the old descriptor ring and allocate a new one. */
1191
1192 dma_free_descriptor_ring(&devAttr->ring);
1193
1194 /* And allocate a new one. */
1195
1196 rc =
1197 dma_alloc_descriptor_ring(&devAttr->ring,
1198 numDescriptors);
1199 if (rc < 0) {
1200 printk(KERN_ERR
1201 "%s: dma_alloc_descriptor_ring(%d) failed\n",
1202 __func__, numDescriptors);
1203 return rc;
1204 }
1205 /* Setup the descriptor for this transfer */
1206
1207 if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
1208 devAttr->ring.physAddr,
1209 devAttr->ring.bytesAllocated,
1210 numDescriptors) < 0) {
1211 printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n",
1212 __func__);
1213 return -EINVAL;
1214 }
1215 } else {
1216 /* We've already got enough ring buffer allocated. All we need to do is reset */
1217 /* any control information, just in case the previous DMA was stopped. */
1218
1219 dmacHw_resetDescriptorControl(devAttr->ring.virtAddr);
1220 }
1221
1222 /* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
1223 /* as last time, then we don't need to call setDataDescriptor again. */
1224
1225 if (dmacHw_setDataDescriptor(&devAttr->config,
1226 devAttr->ring.virtAddr,
1227 (void *)srcData,
1228 (void *)dstData, numBytes) < 0) {
1229 printk(KERN_ERR "%s: dmacHw_setDataDescriptor failed\n",
1230 __func__);
1231 return -EINVAL;
1232 }
1233
1234 /* Remember the critical information for this transfer so that we can eliminate */
1235 /* another call to dma_alloc_descriptors if the caller reuses the same buffers */
1236
1237 devAttr->prevSrcData = srcData;
1238 devAttr->prevDstData = dstData;
1239 devAttr->prevNumBytes = numBytes;
1240
1241 return 0;
1242}
1243
1244EXPORT_SYMBOL(dma_alloc_descriptors);
1245
1246/****************************************************************************/
1247/**
1248* Allocates and sets up descriptors for a double buffered circular buffer.
1249*
1250* This is primarily intended to be used for things like the ingress samples
1251* from a microphone.
1252*
1253* @return
1254* > 0 Number of descriptors actually allocated.
1255* -EINVAL Invalid device type for this kind of transfer
1256* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
1257* -ENOMEM Memory exhausted
1258*/
1259/****************************************************************************/
1260
1261int dma_alloc_double_dst_descriptors(DMA_Handle_t handle, /* DMA Handle */
1262 dma_addr_t srcData, /* Physical address of source data */
1263 dma_addr_t dstData1, /* Physical address of first destination buffer */
1264 dma_addr_t dstData2, /* Physical address of second destination buffer */
1265 size_t numBytes /* Number of bytes in each destination buffer */
1266 ) {
1267 DMA_Channel_t *channel;
1268 DMA_DeviceAttribute_t *devAttr;
1269 int numDst1Descriptors;
1270 int numDst2Descriptors;
1271 int numDescriptors;
1272 size_t ringBytesRequired;
1273 int rc = 0;
1274
1275 channel = HandleToChannel(handle);
1276 if (channel == NULL) {
1277 return -ENODEV;
1278 }
1279
1280 devAttr = &DMA_gDeviceAttribute[channel->devType];
1281
1282 /* Figure out how many descriptors we need. */
1283
1284 /* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
1285 /* srcData, dstData, numBytes); */
1286
1287 numDst1Descriptors =
1288 dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
1289 (void *)dstData1, numBytes);
1290 if (numDst1Descriptors < 0) {
1291 return -EINVAL;
1292 }
1293 numDst2Descriptors =
1294 dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
1295 (void *)dstData2, numBytes);
1296 if (numDst2Descriptors < 0) {
1297 return -EINVAL;
1298 }
1299 numDescriptors = numDst1Descriptors + numDst2Descriptors;
1300 /* printk("numDescriptors: %d\n", numDescriptors); */
1301
1302 /* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
1303 /* a new one. */
1304
1305 ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
1306
1307 /* printk("ringBytesRequired: %d\n", ringBytesRequired); */
1308
1309 if (ringBytesRequired > devAttr->ring.bytesAllocated) {
1310 /* Make sure that this code path is never taken from interrupt context. */
1311 /* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
1312 /* allocation needs to have already been done. */
1313
1314 might_sleep();
1315
1316 /* Free the old descriptor ring and allocate a new one. */
1317
1318 dma_free_descriptor_ring(&devAttr->ring);
1319
1320 /* And allocate a new one. */
1321
1322 rc =
1323 dma_alloc_descriptor_ring(&devAttr->ring,
1324 numDescriptors);
1325 if (rc < 0) {
1326 printk(KERN_ERR
1327 "%s: dma_alloc_descriptor_ring(%d) failed\n",
1328 __func__, ringBytesRequired);
1329 return rc;
1330 }
1331 }
1332
1333 /* Setup the descriptor for this transfer. Since this function is used with */
1334 /* CONTINUOUS DMA operations, we need to reinitialize every time, otherwise */
1335 /* setDataDescriptor will keep trying to append onto the end. */
1336
1337 if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
1338 devAttr->ring.physAddr,
1339 devAttr->ring.bytesAllocated,
1340 numDescriptors) < 0) {
1341 printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n", __func__);
1342 return -EINVAL;
1343 }
1344
1345 /* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
1346 /* as last time, then we don't need to call setDataDescriptor again. */
1347
1348 if (dmacHw_setDataDescriptor(&devAttr->config,
1349 devAttr->ring.virtAddr,
1350 (void *)srcData,
1351 (void *)dstData1, numBytes) < 0) {
1352 printk(KERN_ERR "%s: dmacHw_setDataDescriptor 1 failed\n",
1353 __func__);
1354 return -EINVAL;
1355 }
1356 if (dmacHw_setDataDescriptor(&devAttr->config,
1357 devAttr->ring.virtAddr,
1358 (void *)srcData,
1359 (void *)dstData2, numBytes) < 0) {
1360 printk(KERN_ERR "%s: dmacHw_setDataDescriptor 2 failed\n",
1361 __func__);
1362 return -EINVAL;
1363 }
1364
1365 /* You should use dma_start_transfer rather than dma_transfer_xxx so we don't */
1366 /* try to make the 'prev' variables right. */
1367
1368 devAttr->prevSrcData = 0;
1369 devAttr->prevDstData = 0;
1370 devAttr->prevNumBytes = 0;
1371
1372 return numDescriptors;
1373}
1374
1375EXPORT_SYMBOL(dma_alloc_double_dst_descriptors);
1376
1377/****************************************************************************/
1378/**
1379* Initiates a transfer when the descriptors have already been setup.
1380*
1381* This is a special case, and normally, the dma_transfer_xxx functions should
1382* be used.
1383*
1384* @return
1385* 0 Transfer was started successfully
1386* -ENODEV Invalid handle
1387*/
1388/****************************************************************************/
1389
1390int dma_start_transfer(DMA_Handle_t handle)
1391{
1392 DMA_Channel_t *channel;
1393 DMA_DeviceAttribute_t *devAttr;
1394
1395 channel = HandleToChannel(handle);
1396 if (channel == NULL) {
1397 return -ENODEV;
1398 }
1399 devAttr = &DMA_gDeviceAttribute[channel->devType];
1400
1401 dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
1402 devAttr->ring.virtAddr);
1403
1404 /* Since we got this far, everything went successfully */
1405
1406 return 0;
1407}
1408
1409EXPORT_SYMBOL(dma_start_transfer);
1410
1411/****************************************************************************/
1412/**
1413* Stops a previously started DMA transfer.
1414*
1415* @return
1416* 0 Transfer was stopped successfully
1417* -ENODEV Invalid handle
1418*/
1419/****************************************************************************/
1420
1421int dma_stop_transfer(DMA_Handle_t handle)
1422{
1423 DMA_Channel_t *channel;
1424
1425 channel = HandleToChannel(handle);
1426 if (channel == NULL) {
1427 return -ENODEV;
1428 }
1429
1430 dmacHw_stopTransfer(channel->dmacHwHandle);
1431
1432 return 0;
1433}
1434
1435EXPORT_SYMBOL(dma_stop_transfer);
1436
1437/****************************************************************************/
1438/**
1439* Waits for a DMA to complete by polling. This function is only intended
1440* to be used for testing. Interrupts should be used for most DMA operations.
1441*/
1442/****************************************************************************/
1443
1444int dma_wait_transfer_done(DMA_Handle_t handle)
1445{
1446 DMA_Channel_t *channel;
1447 dmacHw_TRANSFER_STATUS_e status;
1448
1449 channel = HandleToChannel(handle);
1450 if (channel == NULL) {
1451 return -ENODEV;
1452 }
1453
1454 while ((status =
1455 dmacHw_transferCompleted(channel->dmacHwHandle)) ==
1456 dmacHw_TRANSFER_STATUS_BUSY) {
1457 ;
1458 }
1459
1460 if (status == dmacHw_TRANSFER_STATUS_ERROR) {
1461 printk(KERN_ERR "%s: DMA transfer failed\n", __func__);
1462 return -EIO;
1463 }
1464 return 0;
1465}
1466
1467EXPORT_SYMBOL(dma_wait_transfer_done);
1468
1469/****************************************************************************/
1470/**
1471* Initiates a DMA, allocating the descriptors as required.
1472*
1473* @return
1474* 0 Transfer was started successfully
1475* -EINVAL Invalid device type for this kind of transfer
1476* (i.e. the device is _DEV_TO_MEM and not _MEM_TO_DEV)
1477*/
1478/****************************************************************************/
1479
1480int dma_transfer(DMA_Handle_t handle, /* DMA Handle */
1481 dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
1482 dma_addr_t srcData, /* Place to get data to write to device */
1483 dma_addr_t dstData, /* Pointer to device data address */
1484 size_t numBytes /* Number of bytes to transfer to the device */
1485 ) {
1486 DMA_Channel_t *channel;
1487 DMA_DeviceAttribute_t *devAttr;
1488 int rc = 0;
1489
1490 channel = HandleToChannel(handle);
1491 if (channel == NULL) {
1492 return -ENODEV;
1493 }
1494
1495 devAttr = &DMA_gDeviceAttribute[channel->devType];
1496
1497 if (devAttr->config.transferType != transferType) {
1498 return -EINVAL;
1499 }
1500
1501 /* We keep track of the information about the previous request for this */
1502 /* device, and if the attributes match, then we can use the descriptors we setup */
1503 /* the last time, and not have to reinitialize everything. */
1504
1505 {
1506 rc =
1507 dma_alloc_descriptors(handle, transferType, srcData,
1508 dstData, numBytes);
1509 if (rc != 0) {
1510 return rc;
1511 }
1512 }
1513
1514 /* And kick off the transfer */
1515
1516 devAttr->numBytes = numBytes;
1517 devAttr->transferStartTime = timer_get_tick_count();
1518
1519 dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
1520 devAttr->ring.virtAddr);
1521
1522 /* Since we got this far, everything went successfully */
1523
1524 return 0;
1525}
1526
1527EXPORT_SYMBOL(dma_transfer);
1528
1529/****************************************************************************/
1530/**
1531* Set the callback function which will be called when a transfer completes.
1532* If a NULL callback function is set, then no callback will occur.
1533*
1534* @note @a devHandler will be called from IRQ context.
1535*
1536* @return
1537* 0 - Success
1538* -ENODEV - Device handed in is invalid.
1539*/
1540/****************************************************************************/
1541
1542int dma_set_device_handler(DMA_Device_t dev, /* Device to set the callback for. */
1543 DMA_DeviceHandler_t devHandler, /* Function to call when the DMA completes */
1544 void *userData /* Pointer which will be passed to devHandler. */
1545 ) {
1546 DMA_DeviceAttribute_t *devAttr;
1547 unsigned long flags;
1548
1549 if (!IsDeviceValid(dev)) {
1550 return -ENODEV;
1551 }
1552 devAttr = &DMA_gDeviceAttribute[dev];
1553
1554 local_irq_save(flags);
1555
1556 devAttr->userData = userData;
1557 devAttr->devHandler = devHandler;
1558
1559 local_irq_restore(flags);
1560
1561 return 0;
1562}
1563
1564EXPORT_SYMBOL(dma_set_device_handler);
1565
1566/****************************************************************************/
1567/**
1568* Initializes a memory mapping structure
1569*/
1570/****************************************************************************/
1571
1572int dma_init_mem_map(DMA_MemMap_t *memMap)
1573{
1574 memset(memMap, 0, sizeof(*memMap));
1575
1576 init_MUTEX(&memMap->lock);
1577
1578 return 0;
1579}
1580
1581EXPORT_SYMBOL(dma_init_mem_map);
1582
1583/****************************************************************************/
1584/**
1585* Releases any memory currently being held by a memory mapping structure.
1586*/
1587/****************************************************************************/
1588
1589int dma_term_mem_map(DMA_MemMap_t *memMap)
1590{
1591 down(&memMap->lock); /* Just being paranoid */
1592
1593 /* Free up any allocated memory */
1594
1595 up(&memMap->lock);
1596 memset(memMap, 0, sizeof(*memMap));
1597
1598 return 0;
1599}
1600
1601EXPORT_SYMBOL(dma_term_mem_map);
1602
1603/****************************************************************************/
1604/**
1605* Looks at a memory address and categorizes it.
1606*
1607* @return One of the values from the DMA_MemType_t enumeration.
1608*/
1609/****************************************************************************/
1610
1611DMA_MemType_t dma_mem_type(void *addr)
1612{
1613 unsigned long addrVal = (unsigned long)addr;
1614
1615 if (addrVal >= VMALLOC_END) {
1616 /* NOTE: DMA virtual memory space starts at 0xFFxxxxxx */
1617
1618 /* dma_alloc_xxx pages are physically and virtually contiguous */
1619
1620 return DMA_MEM_TYPE_DMA;
1621 }
1622
1623 /* Technically, we could add one more classification. Addresses between VMALLOC_END */
1624 /* and the beginning of the DMA virtual address could be considered to be I/O space. */
1625 /* Right now, nobody cares about this particular classification, so we ignore it. */
1626
1627 if (is_vmalloc_addr(addr)) {
1628 /* Address comes from the vmalloc'd region. Pages are virtually */
1629 /* contiguous but NOT physically contiguous */
1630
1631 return DMA_MEM_TYPE_VMALLOC;
1632 }
1633
1634 if (addrVal >= PAGE_OFFSET) {
1635 /* PAGE_OFFSET is typically 0xC0000000 */
1636
1637 /* kmalloc'd pages are physically contiguous */
1638
1639 return DMA_MEM_TYPE_KMALLOC;
1640 }
1641
1642 return DMA_MEM_TYPE_USER;
1643}
1644
1645EXPORT_SYMBOL(dma_mem_type);
1646
1647/****************************************************************************/
1648/**
1649* Looks at a memory address and determines if we support DMA'ing to/from
1650* that type of memory.
1651*
1652* @return boolean -
1653* return value != 0 means dma supported
1654* return value == 0 means dma not supported
1655*/
1656/****************************************************************************/
1657
1658int dma_mem_supports_dma(void *addr)
1659{
1660 DMA_MemType_t memType = dma_mem_type(addr);
1661
1662 return (memType == DMA_MEM_TYPE_DMA)
1663#if ALLOW_MAP_OF_KMALLOC_MEMORY
1664 || (memType == DMA_MEM_TYPE_KMALLOC)
1665#endif
1666 || (memType == DMA_MEM_TYPE_USER);
1667}
1668
1669EXPORT_SYMBOL(dma_mem_supports_dma);
1670
1671/****************************************************************************/
1672/**
1673* Maps in a memory region such that it can be used for performing a DMA.
1674*
1675* @return
1676*/
1677/****************************************************************************/
1678
1679int dma_map_start(DMA_MemMap_t *memMap, /* Stores state information about the map */
1680 enum dma_data_direction dir /* Direction that the mapping will be going */
1681 ) {
1682 int rc;
1683
1684 down(&memMap->lock);
1685
1686 DMA_MAP_PRINT("memMap: %p\n", memMap);
1687
1688 if (memMap->inUse) {
1689 printk(KERN_ERR "%s: memory map %p is already being used\n",
1690 __func__, memMap);
1691 rc = -EBUSY;
1692 goto out;
1693 }
1694
1695 memMap->inUse = 1;
1696 memMap->dir = dir;
1697 memMap->numRegionsUsed = 0;
1698
1699 rc = 0;
1700
1701out:
1702
1703 DMA_MAP_PRINT("returning %d", rc);
1704
1705 up(&memMap->lock);
1706
1707 return rc;
1708}
1709
1710EXPORT_SYMBOL(dma_map_start);
1711
1712/****************************************************************************/
1713/**
1714* Adds a segment of memory to a memory map. Each segment is both
1715* physically and virtually contiguous.
1716*
1717* @return 0 on success, error code otherwise.
1718*/
1719/****************************************************************************/
1720
1721static int dma_map_add_segment(DMA_MemMap_t *memMap, /* Stores state information about the map */
1722 DMA_Region_t *region, /* Region that the segment belongs to */
1723 void *virtAddr, /* Virtual address of the segment being added */
1724 dma_addr_t physAddr, /* Physical address of the segment being added */
1725 size_t numBytes /* Number of bytes of the segment being added */
1726 ) {
1727 DMA_Segment_t *segment;
1728
1729 DMA_MAP_PRINT("memMap:%p va:%p pa:0x%x #:%d\n", memMap, virtAddr,
1730 physAddr, numBytes);
1731
1732 /* Sanity check */
1733
1734 if (((unsigned long)virtAddr < (unsigned long)region->virtAddr)
1735 || (((unsigned long)virtAddr + numBytes)) >
1736 ((unsigned long)region->virtAddr + region->numBytes)) {
1737 printk(KERN_ERR
1738 "%s: virtAddr %p is outside region @ %p len: %d\n",
1739 __func__, virtAddr, region->virtAddr, region->numBytes);
1740 return -EINVAL;
1741 }
1742
1743 if (region->numSegmentsUsed > 0) {
1744 /* Check to see if this segment is physically contiguous with the previous one */
1745
1746 segment = &region->segment[region->numSegmentsUsed - 1];
1747
1748 if ((segment->physAddr + segment->numBytes) == physAddr) {
1749 /* It is - just add on to the end */
1750
1751 DMA_MAP_PRINT("appending %d bytes to last segment\n",
1752 numBytes);
1753
1754 segment->numBytes += numBytes;
1755
1756 return 0;
1757 }
1758 }
1759
1760 /* Reallocate to hold more segments, if required. */
1761
1762 if (region->numSegmentsUsed >= region->numSegmentsAllocated) {
1763 DMA_Segment_t *newSegment;
1764 size_t oldSize =
1765 region->numSegmentsAllocated * sizeof(*newSegment);
1766 int newAlloc = region->numSegmentsAllocated + 4;
1767 size_t newSize = newAlloc * sizeof(*newSegment);
1768
1769 newSegment = kmalloc(newSize, GFP_KERNEL);
1770 if (newSegment == NULL) {
1771 return -ENOMEM;
1772 }
1773 memcpy(newSegment, region->segment, oldSize);
1774 memset(&((uint8_t *) newSegment)[oldSize], 0,
1775 newSize - oldSize);
1776 kfree(region->segment);
1777
1778 region->numSegmentsAllocated = newAlloc;
1779 region->segment = newSegment;
1780 }
1781
1782 segment = &region->segment[region->numSegmentsUsed];
1783 region->numSegmentsUsed++;
1784
1785 segment->virtAddr = virtAddr;
1786 segment->physAddr = physAddr;
1787 segment->numBytes = numBytes;
1788
1789 DMA_MAP_PRINT("returning success\n");
1790
1791 return 0;
1792}
1793
1794/****************************************************************************/
1795/**
1796* Adds a region of memory to a memory map. Each region is virtually
1797* contiguous, but not necessarily physically contiguous.
1798*
1799* @return 0 on success, error code otherwise.
1800*/
1801/****************************************************************************/
1802
1803int dma_map_add_region(DMA_MemMap_t *memMap, /* Stores state information about the map */
1804 void *mem, /* Virtual address that we want to get a map of */
1805 size_t numBytes /* Number of bytes being mapped */
1806 ) {
1807 unsigned long addr = (unsigned long)mem;
1808 unsigned int offset;
1809 int rc = 0;
1810 DMA_Region_t *region;
1811 dma_addr_t physAddr;
1812
1813 down(&memMap->lock);
1814
1815 DMA_MAP_PRINT("memMap:%p va:%p #:%d\n", memMap, mem, numBytes);
1816
1817 if (!memMap->inUse) {
1818 printk(KERN_ERR "%s: Make sure you call dma_map_start first\n",
1819 __func__);
1820 rc = -EINVAL;
1821 goto out;
1822 }
1823
1824 /* Reallocate to hold more regions. */
1825
1826 if (memMap->numRegionsUsed >= memMap->numRegionsAllocated) {
1827 DMA_Region_t *newRegion;
1828 size_t oldSize =
1829 memMap->numRegionsAllocated * sizeof(*newRegion);
1830 int newAlloc = memMap->numRegionsAllocated + 4;
1831 size_t newSize = newAlloc * sizeof(*newRegion);
1832
1833 newRegion = kmalloc(newSize, GFP_KERNEL);
1834 if (newRegion == NULL) {
1835 rc = -ENOMEM;
1836 goto out;
1837 }
1838 memcpy(newRegion, memMap->region, oldSize);
1839 memset(&((uint8_t *) newRegion)[oldSize], 0, newSize - oldSize);
1840
1841 kfree(memMap->region);
1842
1843 memMap->numRegionsAllocated = newAlloc;
1844 memMap->region = newRegion;
1845 }
1846
1847 region = &memMap->region[memMap->numRegionsUsed];
1848 memMap->numRegionsUsed++;
1849
1850 offset = addr & ~PAGE_MASK;
1851
1852 region->memType = dma_mem_type(mem);
1853 region->virtAddr = mem;
1854 region->numBytes = numBytes;
1855 region->numSegmentsUsed = 0;
1856 region->numLockedPages = 0;
1857 region->lockedPages = NULL;
1858
1859 switch (region->memType) {
1860 case DMA_MEM_TYPE_VMALLOC:
1861 {
1862 atomic_inc(&gDmaStatMemTypeVmalloc);
1863
1864 /* printk(KERN_ERR "%s: vmalloc'd pages are not supported\n", __func__); */
1865
1866 /* vmalloc'd pages are not physically contiguous */
1867
1868 rc = -EINVAL;
1869 break;
1870 }
1871
1872 case DMA_MEM_TYPE_KMALLOC:
1873 {
1874 atomic_inc(&gDmaStatMemTypeKmalloc);
1875
1876 /* kmalloc'd pages are physically contiguous, so they'll have exactly */
1877 /* one segment */
1878
1879#if ALLOW_MAP_OF_KMALLOC_MEMORY
1880 physAddr =
1881 dma_map_single(NULL, mem, numBytes, memMap->dir);
1882 rc = dma_map_add_segment(memMap, region, mem, physAddr,
1883 numBytes);
1884#else
1885 rc = -EINVAL;
1886#endif
1887 break;
1888 }
1889
1890 case DMA_MEM_TYPE_DMA:
1891 {
1892 /* dma_alloc_xxx pages are physically contiguous */
1893
1894 atomic_inc(&gDmaStatMemTypeCoherent);
1895
1896 physAddr = (vmalloc_to_pfn(mem) << PAGE_SHIFT) + offset;
1897
1898 dma_sync_single_for_cpu(NULL, physAddr, numBytes,
1899 memMap->dir);
1900 rc = dma_map_add_segment(memMap, region, mem, physAddr,
1901 numBytes);
1902 break;
1903 }
1904
1905 case DMA_MEM_TYPE_USER:
1906 {
1907 size_t firstPageOffset;
1908 size_t firstPageSize;
1909 struct page **pages;
1910 struct task_struct *userTask;
1911
1912 atomic_inc(&gDmaStatMemTypeUser);
1913
1914#if 1
1915 /* If the pages are user pages, then the dma_mem_map_set_user_task function */
1916 /* must have been previously called. */
1917
1918 if (memMap->userTask == NULL) {
1919 printk(KERN_ERR
1920 "%s: must call dma_mem_map_set_user_task when using user-mode memory\n",
1921 __func__);
1922 return -EINVAL;
1923 }
1924
1925 /* User pages need to be locked. */
1926
1927 firstPageOffset =
1928 (unsigned long)region->virtAddr & (PAGE_SIZE - 1);
1929 firstPageSize = PAGE_SIZE - firstPageOffset;
1930
1931 region->numLockedPages = (firstPageOffset
1932 + region->numBytes +
1933 PAGE_SIZE - 1) / PAGE_SIZE;
1934 pages =
1935 kmalloc(region->numLockedPages *
1936 sizeof(struct page *), GFP_KERNEL);
1937
1938 if (pages == NULL) {
1939 region->numLockedPages = 0;
1940 return -ENOMEM;
1941 }
1942
1943 userTask = memMap->userTask;
1944
1945 down_read(&userTask->mm->mmap_sem);
1946 rc = get_user_pages(userTask, /* task */
1947 userTask->mm, /* mm */
1948 (unsigned long)region->virtAddr, /* start */
1949 region->numLockedPages, /* len */
1950 memMap->dir == DMA_FROM_DEVICE, /* write */
1951 0, /* force */
1952 pages, /* pages (array of pointers to page) */
1953 NULL); /* vmas */
1954 up_read(&userTask->mm->mmap_sem);
1955
1956 if (rc != region->numLockedPages) {
1957 kfree(pages);
1958 region->numLockedPages = 0;
1959
1960 if (rc >= 0) {
1961 rc = -EINVAL;
1962 }
1963 } else {
1964 uint8_t *virtAddr = region->virtAddr;
1965 size_t bytesRemaining;
1966 int pageIdx;
1967
1968 rc = 0; /* Since get_user_pages returns +ve number */
1969
1970 region->lockedPages = pages;
1971
1972 /* We've locked the user pages. Now we need to walk them and figure */
1973 /* out the physical addresses. */
1974
1975 /* The first page may be partial */
1976
1977 dma_map_add_segment(memMap,
1978 region,
1979 virtAddr,
1980 PFN_PHYS(page_to_pfn
1981 (pages[0])) +
1982 firstPageOffset,
1983 firstPageSize);
1984
1985 virtAddr += firstPageSize;
1986 bytesRemaining =
1987 region->numBytes - firstPageSize;
1988
1989 for (pageIdx = 1;
1990 pageIdx < region->numLockedPages;
1991 pageIdx++) {
1992 size_t bytesThisPage =
1993 (bytesRemaining >
1994 PAGE_SIZE ? PAGE_SIZE :
1995 bytesRemaining);
1996
1997 DMA_MAP_PRINT
1998 ("pageIdx:%d pages[pageIdx]=%p pfn=%u phys=%u\n",
1999 pageIdx, pages[pageIdx],
2000 page_to_pfn(pages[pageIdx]),
2001 PFN_PHYS(page_to_pfn
2002 (pages[pageIdx])));
2003
2004 dma_map_add_segment(memMap,
2005 region,
2006 virtAddr,
2007 PFN_PHYS(page_to_pfn
2008 (pages
2009 [pageIdx])),
2010 bytesThisPage);
2011
2012 virtAddr += bytesThisPage;
2013 bytesRemaining -= bytesThisPage;
2014 }
2015 }
2016#else
2017 printk(KERN_ERR
2018 "%s: User mode pages are not yet supported\n",
2019 __func__);
2020
2021 /* user pages are not physically contiguous */
2022
2023 rc = -EINVAL;
2024#endif
2025 break;
2026 }
2027
2028 default:
2029 {
2030 printk(KERN_ERR "%s: Unsupported memory type: %d\n",
2031 __func__, region->memType);
2032
2033 rc = -EINVAL;
2034 break;
2035 }
2036 }
2037
2038 if (rc != 0) {
2039 memMap->numRegionsUsed--;
2040 }
2041
2042out:
2043
2044 DMA_MAP_PRINT("returning %d\n", rc);
2045
2046 up(&memMap->lock);
2047
2048 return rc;
2049}
2050
2051EXPORT_SYMBOL(dma_map_add_segment);
2052
2053/****************************************************************************/
2054/**
2055* Maps in a memory region such that it can be used for performing a DMA.
2056*
2057* @return 0 on success, error code otherwise.
2058*/
2059/****************************************************************************/
2060
2061int dma_map_mem(DMA_MemMap_t *memMap, /* Stores state information about the map */
2062 void *mem, /* Virtual address that we want to get a map of */
2063 size_t numBytes, /* Number of bytes being mapped */
2064 enum dma_data_direction dir /* Direction that the mapping will be going */
2065 ) {
2066 int rc;
2067
2068 rc = dma_map_start(memMap, dir);
2069 if (rc == 0) {
2070 rc = dma_map_add_region(memMap, mem, numBytes);
2071 if (rc < 0) {
2072 /* Since the add fails, this function will fail, and the caller won't */
2073 /* call unmap, so we need to do it here. */
2074
2075 dma_unmap(memMap, 0);
2076 }
2077 }
2078
2079 return rc;
2080}
2081
2082EXPORT_SYMBOL(dma_map_mem);
2083
2084/****************************************************************************/
2085/**
2086* Setup a descriptor ring for a given memory map.
2087*
2088* It is assumed that the descriptor ring has already been initialized, and
2089* this routine will only reallocate a new descriptor ring if the existing
2090* one is too small.
2091*
2092* @return 0 on success, error code otherwise.
2093*/
2094/****************************************************************************/
2095
2096int dma_map_create_descriptor_ring(DMA_Device_t dev, /* DMA device (where the ring is stored) */
2097 DMA_MemMap_t *memMap, /* Memory map that will be used */
2098 dma_addr_t devPhysAddr /* Physical address of device */
2099 ) {
2100 int rc;
2101 int numDescriptors;
2102 DMA_DeviceAttribute_t *devAttr;
2103 DMA_Region_t *region;
2104 DMA_Segment_t *segment;
2105 dma_addr_t srcPhysAddr;
2106 dma_addr_t dstPhysAddr;
2107 int regionIdx;
2108 int segmentIdx;
2109
2110 devAttr = &DMA_gDeviceAttribute[dev];
2111
2112 down(&memMap->lock);
2113
2114 /* Figure out how many descriptors we need */
2115
2116 numDescriptors = 0;
2117 for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
2118 region = &memMap->region[regionIdx];
2119
2120 for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
2121 segmentIdx++) {
2122 segment = &region->segment[segmentIdx];
2123
2124 if (memMap->dir == DMA_TO_DEVICE) {
2125 srcPhysAddr = segment->physAddr;
2126 dstPhysAddr = devPhysAddr;
2127 } else {
2128 srcPhysAddr = devPhysAddr;
2129 dstPhysAddr = segment->physAddr;
2130 }
2131
2132 rc =
2133 dma_calculate_descriptor_count(dev, srcPhysAddr,
2134 dstPhysAddr,
2135 segment->
2136 numBytes);
2137 if (rc < 0) {
2138 printk(KERN_ERR
2139 "%s: dma_calculate_descriptor_count failed: %d\n",
2140 __func__, rc);
2141 goto out;
2142 }
2143 numDescriptors += rc;
2144 }
2145 }
2146
2147 /* Adjust the size of the ring, if it isn't big enough */
2148
2149 if (numDescriptors > devAttr->ring.descriptorsAllocated) {
2150 dma_free_descriptor_ring(&devAttr->ring);
2151 rc =
2152 dma_alloc_descriptor_ring(&devAttr->ring,
2153 numDescriptors);
2154 if (rc < 0) {
2155 printk(KERN_ERR
2156 "%s: dma_alloc_descriptor_ring failed: %d\n",
2157 __func__, rc);
2158 goto out;
2159 }
2160 } else {
2161 rc =
2162 dma_init_descriptor_ring(&devAttr->ring,
2163 numDescriptors);
2164 if (rc < 0) {
2165 printk(KERN_ERR
2166 "%s: dma_init_descriptor_ring failed: %d\n",
2167 __func__, rc);
2168 goto out;
2169 }
2170 }
2171
2172 /* Populate the descriptors */
2173
2174 for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
2175 region = &memMap->region[regionIdx];
2176
2177 for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
2178 segmentIdx++) {
2179 segment = &region->segment[segmentIdx];
2180
2181 if (memMap->dir == DMA_TO_DEVICE) {
2182 srcPhysAddr = segment->physAddr;
2183 dstPhysAddr = devPhysAddr;
2184 } else {
2185 srcPhysAddr = devPhysAddr;
2186 dstPhysAddr = segment->physAddr;
2187 }
2188
2189 rc =
2190 dma_add_descriptors(&devAttr->ring, dev,
2191 srcPhysAddr, dstPhysAddr,
2192 segment->numBytes);
2193 if (rc < 0) {
2194 printk(KERN_ERR
2195 "%s: dma_add_descriptors failed: %d\n",
2196 __func__, rc);
2197 goto out;
2198 }
2199 }
2200 }
2201
2202 rc = 0;
2203
2204out:
2205
2206 up(&memMap->lock);
2207 return rc;
2208}
2209
2210EXPORT_SYMBOL(dma_map_create_descriptor_ring);
2211
2212/****************************************************************************/
2213/**
2214* Maps in a memory region such that it can be used for performing a DMA.
2215*
2216* @return
2217*/
2218/****************************************************************************/
2219
2220int dma_unmap(DMA_MemMap_t *memMap, /* Stores state information about the map */
2221 int dirtied /* non-zero if any of the pages were modified */
2222 ) {
2223 int regionIdx;
2224 int segmentIdx;
2225 DMA_Region_t *region;
2226 DMA_Segment_t *segment;
2227
2228 for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
2229 region = &memMap->region[regionIdx];
2230
2231 for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
2232 segmentIdx++) {
2233 segment = &region->segment[segmentIdx];
2234
2235 switch (region->memType) {
2236 case DMA_MEM_TYPE_VMALLOC:
2237 {
2238 printk(KERN_ERR
2239 "%s: vmalloc'd pages are not yet supported\n",
2240 __func__);
2241 return -EINVAL;
2242 }
2243
2244 case DMA_MEM_TYPE_KMALLOC:
2245 {
2246#if ALLOW_MAP_OF_KMALLOC_MEMORY
2247 dma_unmap_single(NULL,
2248 segment->physAddr,
2249 segment->numBytes,
2250 memMap->dir);
2251#endif
2252 break;
2253 }
2254
2255 case DMA_MEM_TYPE_DMA:
2256 {
2257 dma_sync_single_for_cpu(NULL,
2258 segment->
2259 physAddr,
2260 segment->
2261 numBytes,
2262 memMap->dir);
2263 break;
2264 }
2265
2266 case DMA_MEM_TYPE_USER:
2267 {
2268 /* Nothing to do here. */
2269
2270 break;
2271 }
2272
2273 default:
2274 {
2275 printk(KERN_ERR
2276 "%s: Unsupported memory type: %d\n",
2277 __func__, region->memType);
2278 return -EINVAL;
2279 }
2280 }
2281
2282 segment->virtAddr = NULL;
2283 segment->physAddr = 0;
2284 segment->numBytes = 0;
2285 }
2286
2287 if (region->numLockedPages > 0) {
2288 int pageIdx;
2289
2290 /* Some user pages were locked. We need to go and unlock them now. */
2291
2292 for (pageIdx = 0; pageIdx < region->numLockedPages;
2293 pageIdx++) {
2294 struct page *page =
2295 region->lockedPages[pageIdx];
2296
2297 if (memMap->dir == DMA_FROM_DEVICE) {
2298 SetPageDirty(page);
2299 }
2300 page_cache_release(page);
2301 }
2302 kfree(region->lockedPages);
2303 region->numLockedPages = 0;
2304 region->lockedPages = NULL;
2305 }
2306
2307 region->memType = DMA_MEM_TYPE_NONE;
2308 region->virtAddr = NULL;
2309 region->numBytes = 0;
2310 region->numSegmentsUsed = 0;
2311 }
2312 memMap->userTask = NULL;
2313 memMap->numRegionsUsed = 0;
2314 memMap->inUse = 0;
2315
2316 up(&memMap->lock);
2317
2318 return 0;
2319}
2320
2321EXPORT_SYMBOL(dma_unmap);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-29 08:10:04 -0500