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Xen: Fix retry calls into PRIVCMD_MMAPBATCH*.
[linux-2.6.git] / drivers / dma / mmp_tdma.c
blob9b9366537d73e87c2e6a81113eaa3f0025ae6330
1 /*
2 * Driver For Marvell Two-channel DMA Engine
3 *
4 * Copyright: Marvell International Ltd.
5 *
6 * The code contained herein is licensed under the GNU General Public
7 * License. You may obtain a copy of the GNU General Public License
8 * Version 2 or later at the following locations:
9 *
10 */
11
12 #include <linux/err.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/types.h>
16 #include <linux/interrupt.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/slab.h>
19 #include <linux/dmaengine.h>
20 #include <linux/platform_device.h>
21 #include <linux/device.h>
22 #include <mach/regs-icu.h>
23 #include <linux/platform_data/dma-mmp_tdma.h>
24 #include <linux/of_device.h>
25
26 #include "dmaengine.h"
27
28 /*
29 * Two-Channel DMA registers
30 */
31 #define TDBCR 0x00 /* Byte Count */
32 #define TDSAR 0x10 /* Src Addr */
33 #define TDDAR 0x20 /* Dst Addr */
34 #define TDNDPR 0x30 /* Next Desc */
35 #define TDCR 0x40 /* Control */
36 #define TDCP 0x60 /* Priority*/
37 #define TDCDPR 0x70 /* Current Desc */
38 #define TDIMR 0x80 /* Int Mask */
39 #define TDISR 0xa0 /* Int Status */
40
41 /* Two-Channel DMA Control Register */
42 #define TDCR_SSZ_8_BITS (0x0 << 22) /* Sample Size */
43 #define TDCR_SSZ_12_BITS (0x1 << 22)
44 #define TDCR_SSZ_16_BITS (0x2 << 22)
45 #define TDCR_SSZ_20_BITS (0x3 << 22)
46 #define TDCR_SSZ_24_BITS (0x4 << 22)
47 #define TDCR_SSZ_32_BITS (0x5 << 22)
48 #define TDCR_SSZ_SHIFT (0x1 << 22)
49 #define TDCR_SSZ_MASK (0x7 << 22)
50 #define TDCR_SSPMOD (0x1 << 21) /* SSP MOD */
51 #define TDCR_ABR (0x1 << 20) /* Channel Abort */
52 #define TDCR_CDE (0x1 << 17) /* Close Desc Enable */
53 #define TDCR_PACKMOD (0x1 << 16) /* Pack Mode (ADMA Only) */
54 #define TDCR_CHANACT (0x1 << 14) /* Channel Active */
55 #define TDCR_FETCHND (0x1 << 13) /* Fetch Next Desc */
56 #define TDCR_CHANEN (0x1 << 12) /* Channel Enable */
57 #define TDCR_INTMODE (0x1 << 10) /* Interrupt Mode */
58 #define TDCR_CHAINMOD (0x1 << 9) /* Chain Mode */
59 #define TDCR_BURSTSZ_MSK (0x7 << 6) /* Burst Size */
60 #define TDCR_BURSTSZ_4B (0x0 << 6)
61 #define TDCR_BURSTSZ_8B (0x1 << 6)
62 #define TDCR_BURSTSZ_16B (0x3 << 6)
63 #define TDCR_BURSTSZ_32B (0x6 << 6)
64 #define TDCR_BURSTSZ_64B (0x7 << 6)
65 #define TDCR_BURSTSZ_SQU_32B (0x7 << 6)
66 #define TDCR_BURSTSZ_128B (0x5 << 6)
67 #define TDCR_DSTDIR_MSK (0x3 << 4) /* Dst Direction */
68 #define TDCR_DSTDIR_ADDR_HOLD (0x2 << 4) /* Dst Addr Hold */
69 #define TDCR_DSTDIR_ADDR_INC (0x0 << 4) /* Dst Addr Increment */
70 #define TDCR_SRCDIR_MSK (0x3 << 2) /* Src Direction */
71 #define TDCR_SRCDIR_ADDR_HOLD (0x2 << 2) /* Src Addr Hold */
72 #define TDCR_SRCDIR_ADDR_INC (0x0 << 2) /* Src Addr Increment */
73 #define TDCR_DSTDESCCONT (0x1 << 1)
74 #define TDCR_SRCDESTCONT (0x1 << 0)
75
76 /* Two-Channel DMA Int Mask Register */
77 #define TDIMR_COMP (0x1 << 0)
78
79 /* Two-Channel DMA Int Status Register */
80 #define TDISR_COMP (0x1 << 0)
81
82 /*
83 * Two-Channel DMA Descriptor Struct
84 * NOTE: desc's buf must be aligned to 16 bytes.
85 */
86 struct mmp_tdma_desc {
87 u32 byte_cnt;
88 u32 src_addr;
89 u32 dst_addr;
90 u32 nxt_desc;
91 };
92
93 enum mmp_tdma_type {
94 MMP_AUD_TDMA = 0,
95 PXA910_SQU,
96 };
97
98 #define TDMA_ALIGNMENT 3
99 #define TDMA_MAX_XFER_BYTES SZ_64K
100
101 struct mmp_tdma_chan {
102 struct device *dev;
103 struct dma_chan chan;
104 struct dma_async_tx_descriptor desc;
105 struct tasklet_struct tasklet;
106
107 struct mmp_tdma_desc *desc_arr;
108 phys_addr_t desc_arr_phys;
109 int desc_num;
110 enum dma_transfer_direction dir;
111 dma_addr_t dev_addr;
112 u32 burst_sz;
113 enum dma_slave_buswidth buswidth;
114 enum dma_status status;
115
116 int idx;
117 enum mmp_tdma_type type;
118 int irq;
119 unsigned long reg_base;
120
121 size_t buf_len;
122 size_t period_len;
123 size_t pos;
124 };
125
126 #define TDMA_CHANNEL_NUM 2
127 struct mmp_tdma_device {
128 struct device *dev;
129 void __iomem *base;
130 struct dma_device device;
131 struct mmp_tdma_chan *tdmac[TDMA_CHANNEL_NUM];
132 };
133
134 #define to_mmp_tdma_chan(dchan) container_of(dchan, struct mmp_tdma_chan, chan)
135
136 static void mmp_tdma_chan_set_desc(struct mmp_tdma_chan *tdmac, dma_addr_t phys)
137 {
138 writel(phys, tdmac->reg_base + TDNDPR);
139 writel(readl(tdmac->reg_base + TDCR) | TDCR_FETCHND,
140 tdmac->reg_base + TDCR);
141 }
142
143 static void mmp_tdma_enable_chan(struct mmp_tdma_chan *tdmac)
144 {
145 /* enable irq */
146 writel(TDIMR_COMP, tdmac->reg_base + TDIMR);
147 /* enable dma chan */
148 writel(readl(tdmac->reg_base + TDCR) | TDCR_CHANEN,
149 tdmac->reg_base + TDCR);
150 tdmac->status = DMA_IN_PROGRESS;
151 }
152
153 static void mmp_tdma_disable_chan(struct mmp_tdma_chan *tdmac)
154 {
155 writel(readl(tdmac->reg_base + TDCR) & ~TDCR_CHANEN,
156 tdmac->reg_base + TDCR);
157
158 /* disable irq */
159 writel(0, tdmac->reg_base + TDIMR);
160
161 tdmac->status = DMA_SUCCESS;
162 }
163
164 static void mmp_tdma_resume_chan(struct mmp_tdma_chan *tdmac)
165 {
166 writel(readl(tdmac->reg_base + TDCR) | TDCR_CHANEN,
167 tdmac->reg_base + TDCR);
168 tdmac->status = DMA_IN_PROGRESS;
169 }
170
171 static void mmp_tdma_pause_chan(struct mmp_tdma_chan *tdmac)
172 {
173 writel(readl(tdmac->reg_base + TDCR) & ~TDCR_CHANEN,
174 tdmac->reg_base + TDCR);
175 tdmac->status = DMA_PAUSED;
176 }
177
178 static int mmp_tdma_config_chan(struct mmp_tdma_chan *tdmac)
179 {
180 unsigned int tdcr;
181
182 mmp_tdma_disable_chan(tdmac);
183
184 if (tdmac->dir == DMA_MEM_TO_DEV)
185 tdcr = TDCR_DSTDIR_ADDR_HOLD | TDCR_SRCDIR_ADDR_INC;
186 else if (tdmac->dir == DMA_DEV_TO_MEM)
187 tdcr = TDCR_SRCDIR_ADDR_HOLD | TDCR_DSTDIR_ADDR_INC;
188
189 if (tdmac->type == MMP_AUD_TDMA) {
190 tdcr |= TDCR_PACKMOD;
191
192 switch (tdmac->burst_sz) {
193 case 4:
194 tdcr |= TDCR_BURSTSZ_4B;
195 break;
196 case 8:
197 tdcr |= TDCR_BURSTSZ_8B;
198 break;
199 case 16:
200 tdcr |= TDCR_BURSTSZ_16B;
201 break;
202 case 32:
203 tdcr |= TDCR_BURSTSZ_32B;
204 break;
205 case 64:
206 tdcr |= TDCR_BURSTSZ_64B;
207 break;
208 case 128:
209 tdcr |= TDCR_BURSTSZ_128B;
210 break;
211 default:
212 dev_err(tdmac->dev, "mmp_tdma: unknown burst size.\n");
213 return -EINVAL;
214 }
215
216 switch (tdmac->buswidth) {
217 case DMA_SLAVE_BUSWIDTH_1_BYTE:
218 tdcr |= TDCR_SSZ_8_BITS;
219 break;
220 case DMA_SLAVE_BUSWIDTH_2_BYTES:
221 tdcr |= TDCR_SSZ_16_BITS;
222 break;
223 case DMA_SLAVE_BUSWIDTH_4_BYTES:
224 tdcr |= TDCR_SSZ_32_BITS;
225 break;
226 default:
227 dev_err(tdmac->dev, "mmp_tdma: unknown bus size.\n");
228 return -EINVAL;
229 }
230 } else if (tdmac->type == PXA910_SQU) {
231 tdcr |= TDCR_BURSTSZ_SQU_32B;
232 tdcr |= TDCR_SSPMOD;
233 }
234
235 writel(tdcr, tdmac->reg_base + TDCR);
236 return 0;
237 }
238
239 static int mmp_tdma_clear_chan_irq(struct mmp_tdma_chan *tdmac)
240 {
241 u32 reg = readl(tdmac->reg_base + TDISR);
242
243 if (reg & TDISR_COMP) {
244 /* clear irq */
245 reg &= ~TDISR_COMP;
246 writel(reg, tdmac->reg_base + TDISR);
247
248 return 0;
249 }
250 return -EAGAIN;
251 }
252
253 static irqreturn_t mmp_tdma_chan_handler(int irq, void *dev_id)
254 {
255 struct mmp_tdma_chan *tdmac = dev_id;
256
257 if (mmp_tdma_clear_chan_irq(tdmac) == 0) {
258 tdmac->pos = (tdmac->pos + tdmac->period_len) % tdmac->buf_len;
259 tasklet_schedule(&tdmac->tasklet);
260 return IRQ_HANDLED;
261 } else
262 return IRQ_NONE;
263 }
264
265 static irqreturn_t mmp_tdma_int_handler(int irq, void *dev_id)
266 {
267 struct mmp_tdma_device *tdev = dev_id;
268 int i, ret;
269 int irq_num = 0;
270
271 for (i = 0; i < TDMA_CHANNEL_NUM; i++) {
272 struct mmp_tdma_chan *tdmac = tdev->tdmac[i];
273
274 ret = mmp_tdma_chan_handler(irq, tdmac);
275 if (ret == IRQ_HANDLED)
276 irq_num++;
277 }
278
279 if (irq_num)
280 return IRQ_HANDLED;
281 else
282 return IRQ_NONE;
283 }
284
285 static void dma_do_tasklet(unsigned long data)
286 {
287 struct mmp_tdma_chan *tdmac = (struct mmp_tdma_chan *)data;
288
289 if (tdmac->desc.callback)
290 tdmac->desc.callback(tdmac->desc.callback_param);
291
292 }
293
294 static void mmp_tdma_free_descriptor(struct mmp_tdma_chan *tdmac)
295 {
296 struct gen_pool *gpool;
297 int size = tdmac->desc_num * sizeof(struct mmp_tdma_desc);
298
299 gpool = sram_get_gpool("asram");
300 if (tdmac->desc_arr)
301 gen_pool_free(gpool, (unsigned long)tdmac->desc_arr,
302 size);
303 tdmac->desc_arr = NULL;
304
305 return;
306 }
307
308 static dma_cookie_t mmp_tdma_tx_submit(struct dma_async_tx_descriptor *tx)
309 {
310 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(tx->chan);
311
312 mmp_tdma_chan_set_desc(tdmac, tdmac->desc_arr_phys);
313
314 return 0;
315 }
316
317 static int mmp_tdma_alloc_chan_resources(struct dma_chan *chan)
318 {
319 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
320 int ret;
321
322 dma_async_tx_descriptor_init(&tdmac->desc, chan);
323 tdmac->desc.tx_submit = mmp_tdma_tx_submit;
324
325 if (tdmac->irq) {
326 ret = devm_request_irq(tdmac->dev, tdmac->irq,
327 mmp_tdma_chan_handler, IRQF_DISABLED, "tdma", tdmac);
328 if (ret)
329 return ret;
330 }
331 return 1;
332 }
333
334 static void mmp_tdma_free_chan_resources(struct dma_chan *chan)
335 {
336 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
337
338 if (tdmac->irq)
339 devm_free_irq(tdmac->dev, tdmac->irq, tdmac);
340 mmp_tdma_free_descriptor(tdmac);
341 return;
342 }
343
344 struct mmp_tdma_desc *mmp_tdma_alloc_descriptor(struct mmp_tdma_chan *tdmac)
345 {
346 struct gen_pool *gpool;
347 int size = tdmac->desc_num * sizeof(struct mmp_tdma_desc);
348
349 gpool = sram_get_gpool("asram");
350 if (!gpool)
351 return NULL;
352
353 tdmac->desc_arr = (void *)gen_pool_alloc(gpool, size);
354 if (!tdmac->desc_arr)
355 return NULL;
356
357 tdmac->desc_arr_phys = gen_pool_virt_to_phys(gpool,
358 (unsigned long)tdmac->desc_arr);
359
360 return tdmac->desc_arr;
361 }
362
363 static struct dma_async_tx_descriptor *mmp_tdma_prep_dma_cyclic(
364 struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
365 size_t period_len, enum dma_transfer_direction direction,
366 unsigned long flags, void *context)
367 {
368 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
369 struct mmp_tdma_desc *desc;
370 int num_periods = buf_len / period_len;
371 int i = 0, buf = 0;
372
373 if (tdmac->status != DMA_SUCCESS)
374 return NULL;
375
376 if (period_len > TDMA_MAX_XFER_BYTES) {
377 dev_err(tdmac->dev,
378 "maximum period size exceeded: %d > %d\n",
379 period_len, TDMA_MAX_XFER_BYTES);
380 goto err_out;
381 }
382
383 tdmac->status = DMA_IN_PROGRESS;
384 tdmac->desc_num = num_periods;
385 desc = mmp_tdma_alloc_descriptor(tdmac);
386 if (!desc)
387 goto err_out;
388
389 while (buf < buf_len) {
390 desc = &tdmac->desc_arr[i];
391
392 if (i + 1 == num_periods)
393 desc->nxt_desc = tdmac->desc_arr_phys;
394 else
395 desc->nxt_desc = tdmac->desc_arr_phys +
396 sizeof(*desc) * (i + 1);
397
398 if (direction == DMA_MEM_TO_DEV) {
399 desc->src_addr = dma_addr;
400 desc->dst_addr = tdmac->dev_addr;
401 } else {
402 desc->src_addr = tdmac->dev_addr;
403 desc->dst_addr = dma_addr;
404 }
405 desc->byte_cnt = period_len;
406 dma_addr += period_len;
407 buf += period_len;
408 i++;
409 }
410
411 tdmac->buf_len = buf_len;
412 tdmac->period_len = period_len;
413 tdmac->pos = 0;
414
415 return &tdmac->desc;
416
417 err_out:
418 tdmac->status = DMA_ERROR;
419 return NULL;
420 }
421
422 static int mmp_tdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
423 unsigned long arg)
424 {
425 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
426 struct dma_slave_config *dmaengine_cfg = (void *)arg;
427 int ret = 0;
428
429 switch (cmd) {
430 case DMA_TERMINATE_ALL:
431 mmp_tdma_disable_chan(tdmac);
432 break;
433 case DMA_PAUSE:
434 mmp_tdma_pause_chan(tdmac);
435 break;
436 case DMA_RESUME:
437 mmp_tdma_resume_chan(tdmac);
438 break;
439 case DMA_SLAVE_CONFIG:
440 if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
441 tdmac->dev_addr = dmaengine_cfg->src_addr;
442 tdmac->burst_sz = dmaengine_cfg->src_maxburst;
443 tdmac->buswidth = dmaengine_cfg->src_addr_width;
444 } else {
445 tdmac->dev_addr = dmaengine_cfg->dst_addr;
446 tdmac->burst_sz = dmaengine_cfg->dst_maxburst;
447 tdmac->buswidth = dmaengine_cfg->dst_addr_width;
448 }
449 tdmac->dir = dmaengine_cfg->direction;
450 return mmp_tdma_config_chan(tdmac);
451 default:
452 ret = -ENOSYS;
453 }
454
455 return ret;
456 }
457
458 static enum dma_status mmp_tdma_tx_status(struct dma_chan *chan,
459 dma_cookie_t cookie, struct dma_tx_state *txstate)
460 {
461 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
462
463 dma_set_residue(txstate, tdmac->buf_len - tdmac->pos);
464
465 return tdmac->status;
466 }
467
468 static void mmp_tdma_issue_pending(struct dma_chan *chan)
469 {
470 struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
471
472 mmp_tdma_enable_chan(tdmac);
473 }
474
475 static int mmp_tdma_remove(struct platform_device *pdev)
476 {
477 struct mmp_tdma_device *tdev = platform_get_drvdata(pdev);
478
479 dma_async_device_unregister(&tdev->device);
480 return 0;
481 }
482
483 static int mmp_tdma_chan_init(struct mmp_tdma_device *tdev,
484 int idx, int irq, int type)
485 {
486 struct mmp_tdma_chan *tdmac;
487
488 if (idx >= TDMA_CHANNEL_NUM) {
489 dev_err(tdev->dev, "too many channels for device!\n");
490 return -EINVAL;
491 }
492
493 /* alloc channel */
494 tdmac = devm_kzalloc(tdev->dev, sizeof(*tdmac), GFP_KERNEL);
495 if (!tdmac) {
496 dev_err(tdev->dev, "no free memory for DMA channels!\n");
497 return -ENOMEM;
498 }
499 if (irq)
500 tdmac->irq = irq;
501 tdmac->dev = tdev->dev;
502 tdmac->chan.device = &tdev->device;
503 tdmac->idx = idx;
504 tdmac->type = type;
505 tdmac->reg_base = (unsigned long)tdev->base + idx * 4;
506 tdmac->status = DMA_SUCCESS;
507 tdev->tdmac[tdmac->idx] = tdmac;
508 tasklet_init(&tdmac->tasklet, dma_do_tasklet, (unsigned long)tdmac);
509
510 /* add the channel to tdma_chan list */
511 list_add_tail(&tdmac->chan.device_node,
512 &tdev->device.channels);
513 return 0;
514 }
515
516 static struct of_device_id mmp_tdma_dt_ids[] = {
517 { .compatible = "marvell,adma-1.0", .data = (void *)MMP_AUD_TDMA},
518 { .compatible = "marvell,pxa910-squ", .data = (void *)PXA910_SQU},
519 {}
520 };
521 MODULE_DEVICE_TABLE(of, mmp_tdma_dt_ids);
522
523 static int mmp_tdma_probe(struct platform_device *pdev)
524 {
525 enum mmp_tdma_type type;
526 const struct of_device_id *of_id;
527 struct mmp_tdma_device *tdev;
528 struct resource *iores;
529 int i, ret;
530 int irq = 0, irq_num = 0;
531 int chan_num = TDMA_CHANNEL_NUM;
532
533 of_id = of_match_device(mmp_tdma_dt_ids, &pdev->dev);
534 if (of_id)
535 type = (enum mmp_tdma_type) of_id->data;
536 else
537 type = platform_get_device_id(pdev)->driver_data;
538
539 /* always have couple channels */
540 tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
541 if (!tdev)
542 return -ENOMEM;
543
544 tdev->dev = &pdev->dev;
545
546 for (i = 0; i < chan_num; i++) {
547 if (platform_get_irq(pdev, i) > 0)
548 irq_num++;
549 }
550
551 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
552 if (!iores)
553 return -EINVAL;
554
555 tdev->base = devm_ioremap_resource(&pdev->dev, iores);
556 if (IS_ERR(tdev->base))
557 return PTR_ERR(tdev->base);
558
559 INIT_LIST_HEAD(&tdev->device.channels);
560
561 if (irq_num != chan_num) {
562 irq = platform_get_irq(pdev, 0);
563 ret = devm_request_irq(&pdev->dev, irq,
564 mmp_tdma_int_handler, IRQF_DISABLED, "tdma", tdev);
565 if (ret)
566 return ret;
567 }
568
569 /* initialize channel parameters */
570 for (i = 0; i < chan_num; i++) {
571 irq = (irq_num != chan_num) ? 0 : platform_get_irq(pdev, i);
572 ret = mmp_tdma_chan_init(tdev, i, irq, type);
573 if (ret)
574 return ret;
575 }
576
577 dma_cap_set(DMA_SLAVE, tdev->device.cap_mask);
578 dma_cap_set(DMA_CYCLIC, tdev->device.cap_mask);
579 tdev->device.dev = &pdev->dev;
580 tdev->device.device_alloc_chan_resources =
581 mmp_tdma_alloc_chan_resources;
582 tdev->device.device_free_chan_resources =
583 mmp_tdma_free_chan_resources;
584 tdev->device.device_prep_dma_cyclic = mmp_tdma_prep_dma_cyclic;
585 tdev->device.device_tx_status = mmp_tdma_tx_status;
586 tdev->device.device_issue_pending = mmp_tdma_issue_pending;
587 tdev->device.device_control = mmp_tdma_control;
588 tdev->device.copy_align = TDMA_ALIGNMENT;
589
590 dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
591 platform_set_drvdata(pdev, tdev);
592
593 ret = dma_async_device_register(&tdev->device);
594 if (ret) {
595 dev_err(tdev->device.dev, "unable to register\n");
596 return ret;
597 }
598
599 dev_info(tdev->device.dev, "initialized\n");
600 return 0;
601 }
602
603 static const struct platform_device_id mmp_tdma_id_table[] = {
604 { "mmp-adma", MMP_AUD_TDMA },
605 { "pxa910-squ", PXA910_SQU },
606 { },
607 };
608
609 static struct platform_driver mmp_tdma_driver = {
610 .driver = {
611 .name = "mmp-tdma",
612 .owner = THIS_MODULE,
613 .of_match_table = mmp_tdma_dt_ids,
614 },
615 .id_table = mmp_tdma_id_table,
616 .probe = mmp_tdma_probe,
617 .remove = mmp_tdma_remove,
618 };
619
620 module_platform_driver(mmp_tdma_driver);
621
622 MODULE_LICENSE("GPL");
623 MODULE_DESCRIPTION("MMP Two-Channel DMA Driver");
624 MODULE_ALIAS("platform:mmp-tdma");
625 MODULE_AUTHOR("Leo Yan <leoy@marvell.com>");
626 MODULE_AUTHOR("Zhangfei Gao <zhangfei.gao@marvell.com>");
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