xref: /linux/drivers/usb/mtu3/mtu3_qmu.c (revision 0e9b70c1e3623fa110fb6be553e644524228ef60)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * mtu3_qmu.c - Queue Management Unit driver for device controller
4  *
5  * Copyright (C) 2016 MediaTek Inc.
6  *
7  * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
8  */
9 
10 /*
11  * Queue Management Unit (QMU) is designed to unload SW effort
12  * to serve DMA interrupts.
13  * By preparing General Purpose Descriptor (GPD) and Buffer Descriptor (BD),
14  * SW links data buffers and triggers QMU to send / receive data to
15  * host / from device at a time.
16  * And now only GPD is supported.
17  *
18  * For more detailed information, please refer to QMU Programming Guide
19  */
20 
21 #include <linux/dmapool.h>
22 #include <linux/iopoll.h>
23 
24 #include "mtu3.h"
25 #include "mtu3_trace.h"
26 
27 #define QMU_CHECKSUM_LEN	16
28 
29 #define GPD_FLAGS_HWO	BIT(0)
30 #define GPD_FLAGS_BDP	BIT(1)
31 #define GPD_FLAGS_BPS	BIT(2)
32 #define GPD_FLAGS_ZLP	BIT(6)
33 #define GPD_FLAGS_IOC	BIT(7)
34 #define GET_GPD_HWO(gpd)	(le32_to_cpu((gpd)->dw0_info) & GPD_FLAGS_HWO)
35 
36 #define GPD_RX_BUF_LEN_OG(x)	(((x) & 0xffff) << 16)
37 #define GPD_RX_BUF_LEN_EL(x)	(((x) & 0xfffff) << 12)
38 #define GPD_RX_BUF_LEN(mtu, x)	\
39 ({				\
40 	typeof(x) x_ = (x);	\
41 	((mtu)->gen2cp) ? GPD_RX_BUF_LEN_EL(x_) : GPD_RX_BUF_LEN_OG(x_); \
42 })
43 
44 #define GPD_DATA_LEN_OG(x)	((x) & 0xffff)
45 #define GPD_DATA_LEN_EL(x)	((x) & 0xfffff)
46 #define GPD_DATA_LEN(mtu, x)	\
47 ({				\
48 	typeof(x) x_ = (x);	\
49 	((mtu)->gen2cp) ? GPD_DATA_LEN_EL(x_) : GPD_DATA_LEN_OG(x_); \
50 })
51 
52 #define GPD_EXT_FLAG_ZLP	BIT(29)
53 #define GPD_EXT_NGP_OG(x)	(((x) & 0xf) << 20)
54 #define GPD_EXT_BUF_OG(x)	(((x) & 0xf) << 16)
55 #define GPD_EXT_NGP_EL(x)	(((x) & 0xf) << 28)
56 #define GPD_EXT_BUF_EL(x)	(((x) & 0xf) << 24)
57 #define GPD_EXT_NGP(mtu, x)	\
58 ({				\
59 	typeof(x) x_ = (x);	\
60 	((mtu)->gen2cp) ? GPD_EXT_NGP_EL(x_) : GPD_EXT_NGP_OG(x_); \
61 })
62 
63 #define GPD_EXT_BUF(mtu, x)	\
64 ({				\
65 	typeof(x) x_ = (x);	\
66 	((mtu)->gen2cp) ? GPD_EXT_BUF_EL(x_) : GPD_EXT_BUF_OG(x_); \
67 })
68 
69 #define HILO_GEN64(hi, lo) (((u64)(hi) << 32) + (lo))
70 #define HILO_DMA(hi, lo)	\
71 	((dma_addr_t)HILO_GEN64((le32_to_cpu(hi)), (le32_to_cpu(lo))))
72 
73 static dma_addr_t read_txq_cur_addr(void __iomem *mbase, u8 epnum)
74 {
75 	u32 txcpr;
76 	u32 txhiar;
77 
78 	txcpr = mtu3_readl(mbase, USB_QMU_TQCPR(epnum));
79 	txhiar = mtu3_readl(mbase, USB_QMU_TQHIAR(epnum));
80 
81 	return HILO_DMA(QMU_CUR_GPD_ADDR_HI(txhiar), txcpr);
82 }
83 
84 static dma_addr_t read_rxq_cur_addr(void __iomem *mbase, u8 epnum)
85 {
86 	u32 rxcpr;
87 	u32 rxhiar;
88 
89 	rxcpr = mtu3_readl(mbase, USB_QMU_RQCPR(epnum));
90 	rxhiar = mtu3_readl(mbase, USB_QMU_RQHIAR(epnum));
91 
92 	return HILO_DMA(QMU_CUR_GPD_ADDR_HI(rxhiar), rxcpr);
93 }
94 
95 static void write_txq_start_addr(void __iomem *mbase, u8 epnum, dma_addr_t dma)
96 {
97 	u32 tqhiar;
98 
99 	mtu3_writel(mbase, USB_QMU_TQSAR(epnum),
100 		    cpu_to_le32(lower_32_bits(dma)));
101 	tqhiar = mtu3_readl(mbase, USB_QMU_TQHIAR(epnum));
102 	tqhiar &= ~QMU_START_ADDR_HI_MSK;
103 	tqhiar |= QMU_START_ADDR_HI(upper_32_bits(dma));
104 	mtu3_writel(mbase, USB_QMU_TQHIAR(epnum), tqhiar);
105 }
106 
107 static void write_rxq_start_addr(void __iomem *mbase, u8 epnum, dma_addr_t dma)
108 {
109 	u32 rqhiar;
110 
111 	mtu3_writel(mbase, USB_QMU_RQSAR(epnum),
112 		    cpu_to_le32(lower_32_bits(dma)));
113 	rqhiar = mtu3_readl(mbase, USB_QMU_RQHIAR(epnum));
114 	rqhiar &= ~QMU_START_ADDR_HI_MSK;
115 	rqhiar |= QMU_START_ADDR_HI(upper_32_bits(dma));
116 	mtu3_writel(mbase, USB_QMU_RQHIAR(epnum), rqhiar);
117 }
118 
119 static struct qmu_gpd *gpd_dma_to_virt(struct mtu3_gpd_ring *ring,
120 		dma_addr_t dma_addr)
121 {
122 	dma_addr_t dma_base = ring->dma;
123 	struct qmu_gpd *gpd_head = ring->start;
124 	u32 offset = (dma_addr - dma_base) / sizeof(*gpd_head);
125 
126 	if (offset >= MAX_GPD_NUM)
127 		return NULL;
128 
129 	return gpd_head + offset;
130 }
131 
132 static dma_addr_t gpd_virt_to_dma(struct mtu3_gpd_ring *ring,
133 		struct qmu_gpd *gpd)
134 {
135 	dma_addr_t dma_base = ring->dma;
136 	struct qmu_gpd *gpd_head = ring->start;
137 	u32 offset;
138 
139 	offset = gpd - gpd_head;
140 	if (offset >= MAX_GPD_NUM)
141 		return 0;
142 
143 	return dma_base + (offset * sizeof(*gpd));
144 }
145 
146 static void gpd_ring_init(struct mtu3_gpd_ring *ring, struct qmu_gpd *gpd)
147 {
148 	ring->start = gpd;
149 	ring->enqueue = gpd;
150 	ring->dequeue = gpd;
151 	ring->end = gpd + MAX_GPD_NUM - 1;
152 }
153 
154 static void reset_gpd_list(struct mtu3_ep *mep)
155 {
156 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
157 	struct qmu_gpd *gpd = ring->start;
158 
159 	if (gpd) {
160 		gpd->dw0_info &= cpu_to_le32(~GPD_FLAGS_HWO);
161 		gpd_ring_init(ring, gpd);
162 	}
163 }
164 
165 int mtu3_gpd_ring_alloc(struct mtu3_ep *mep)
166 {
167 	struct qmu_gpd *gpd;
168 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
169 
170 	/* software own all gpds as default */
171 	gpd = dma_pool_zalloc(mep->mtu->qmu_gpd_pool, GFP_ATOMIC, &ring->dma);
172 	if (gpd == NULL)
173 		return -ENOMEM;
174 
175 	gpd_ring_init(ring, gpd);
176 
177 	return 0;
178 }
179 
180 void mtu3_gpd_ring_free(struct mtu3_ep *mep)
181 {
182 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
183 
184 	dma_pool_free(mep->mtu->qmu_gpd_pool,
185 			ring->start, ring->dma);
186 	memset(ring, 0, sizeof(*ring));
187 }
188 
189 void mtu3_qmu_resume(struct mtu3_ep *mep)
190 {
191 	struct mtu3 *mtu = mep->mtu;
192 	void __iomem *mbase = mtu->mac_base;
193 	int epnum = mep->epnum;
194 	u32 offset;
195 
196 	offset = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
197 
198 	mtu3_writel(mbase, offset, QMU_Q_RESUME);
199 	if (!(mtu3_readl(mbase, offset) & QMU_Q_ACTIVE))
200 		mtu3_writel(mbase, offset, QMU_Q_RESUME);
201 }
202 
203 static struct qmu_gpd *advance_enq_gpd(struct mtu3_gpd_ring *ring)
204 {
205 	if (ring->enqueue < ring->end)
206 		ring->enqueue++;
207 	else
208 		ring->enqueue = ring->start;
209 
210 	return ring->enqueue;
211 }
212 
213 static struct qmu_gpd *advance_deq_gpd(struct mtu3_gpd_ring *ring)
214 {
215 	if (ring->dequeue < ring->end)
216 		ring->dequeue++;
217 	else
218 		ring->dequeue = ring->start;
219 
220 	return ring->dequeue;
221 }
222 
223 /* check if a ring is emtpy */
224 static int gpd_ring_empty(struct mtu3_gpd_ring *ring)
225 {
226 	struct qmu_gpd *enq = ring->enqueue;
227 	struct qmu_gpd *next;
228 
229 	if (ring->enqueue < ring->end)
230 		next = enq + 1;
231 	else
232 		next = ring->start;
233 
234 	/* one gpd is reserved to simplify gpd preparation */
235 	return next == ring->dequeue;
236 }
237 
238 int mtu3_prepare_transfer(struct mtu3_ep *mep)
239 {
240 	return gpd_ring_empty(&mep->gpd_ring);
241 }
242 
243 static int mtu3_prepare_tx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
244 {
245 	struct qmu_gpd *enq;
246 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
247 	struct qmu_gpd *gpd = ring->enqueue;
248 	struct usb_request *req = &mreq->request;
249 	struct mtu3 *mtu = mep->mtu;
250 	dma_addr_t enq_dma;
251 	u32 ext_addr;
252 
253 	gpd->dw0_info = 0;	/* SW own it */
254 	gpd->buffer = cpu_to_le32(lower_32_bits(req->dma));
255 	ext_addr = GPD_EXT_BUF(mtu, upper_32_bits(req->dma));
256 	gpd->dw3_info = cpu_to_le32(GPD_DATA_LEN(mtu, req->length));
257 
258 	/* get the next GPD */
259 	enq = advance_enq_gpd(ring);
260 	enq_dma = gpd_virt_to_dma(ring, enq);
261 	dev_dbg(mep->mtu->dev, "TX-EP%d queue gpd=%p, enq=%p, qdma=%pad\n",
262 		mep->epnum, gpd, enq, &enq_dma);
263 
264 	enq->dw0_info &= cpu_to_le32(~GPD_FLAGS_HWO);
265 	gpd->next_gpd = cpu_to_le32(lower_32_bits(enq_dma));
266 	ext_addr |= GPD_EXT_NGP(mtu, upper_32_bits(enq_dma));
267 	gpd->dw0_info = cpu_to_le32(ext_addr);
268 
269 	if (req->zero) {
270 		if (mtu->gen2cp)
271 			gpd->dw0_info |= cpu_to_le32(GPD_FLAGS_ZLP);
272 		else
273 			gpd->dw3_info |= cpu_to_le32(GPD_EXT_FLAG_ZLP);
274 	}
275 
276 	/* prevent reorder, make sure GPD's HWO is set last */
277 	mb();
278 	gpd->dw0_info |= cpu_to_le32(GPD_FLAGS_IOC | GPD_FLAGS_HWO);
279 
280 	mreq->gpd = gpd;
281 	trace_mtu3_prepare_gpd(mep, gpd);
282 
283 	return 0;
284 }
285 
286 static int mtu3_prepare_rx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
287 {
288 	struct qmu_gpd *enq;
289 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
290 	struct qmu_gpd *gpd = ring->enqueue;
291 	struct usb_request *req = &mreq->request;
292 	struct mtu3 *mtu = mep->mtu;
293 	dma_addr_t enq_dma;
294 	u32 ext_addr;
295 
296 	gpd->dw0_info = 0;	/* SW own it */
297 	gpd->buffer = cpu_to_le32(lower_32_bits(req->dma));
298 	ext_addr = GPD_EXT_BUF(mtu, upper_32_bits(req->dma));
299 	gpd->dw0_info = cpu_to_le32(GPD_RX_BUF_LEN(mtu, req->length));
300 
301 	/* get the next GPD */
302 	enq = advance_enq_gpd(ring);
303 	enq_dma = gpd_virt_to_dma(ring, enq);
304 	dev_dbg(mep->mtu->dev, "RX-EP%d queue gpd=%p, enq=%p, qdma=%pad\n",
305 		mep->epnum, gpd, enq, &enq_dma);
306 
307 	enq->dw0_info &= cpu_to_le32(~GPD_FLAGS_HWO);
308 	gpd->next_gpd = cpu_to_le32(lower_32_bits(enq_dma));
309 	ext_addr |= GPD_EXT_NGP(mtu, upper_32_bits(enq_dma));
310 	gpd->dw3_info = cpu_to_le32(ext_addr);
311 	/* prevent reorder, make sure GPD's HWO is set last */
312 	mb();
313 	gpd->dw0_info |= cpu_to_le32(GPD_FLAGS_IOC | GPD_FLAGS_HWO);
314 
315 	mreq->gpd = gpd;
316 	trace_mtu3_prepare_gpd(mep, gpd);
317 
318 	return 0;
319 }
320 
321 void mtu3_insert_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
322 {
323 
324 	if (mep->is_in)
325 		mtu3_prepare_tx_gpd(mep, mreq);
326 	else
327 		mtu3_prepare_rx_gpd(mep, mreq);
328 }
329 
330 int mtu3_qmu_start(struct mtu3_ep *mep)
331 {
332 	struct mtu3 *mtu = mep->mtu;
333 	void __iomem *mbase = mtu->mac_base;
334 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
335 	u8 epnum = mep->epnum;
336 
337 	if (mep->is_in) {
338 		/* set QMU start address */
339 		write_txq_start_addr(mbase, epnum, ring->dma);
340 		mtu3_setbits(mbase, MU3D_EP_TXCR0(epnum), TX_DMAREQEN);
341 		/* send zero length packet according to ZLP flag in GPD */
342 		mtu3_setbits(mbase, U3D_QCR1, QMU_TX_ZLP(epnum));
343 		mtu3_writel(mbase, U3D_TQERRIESR0,
344 				QMU_TX_LEN_ERR(epnum) | QMU_TX_CS_ERR(epnum));
345 
346 		if (mtu3_readl(mbase, USB_QMU_TQCSR(epnum)) & QMU_Q_ACTIVE) {
347 			dev_warn(mtu->dev, "Tx %d Active Now!\n", epnum);
348 			return 0;
349 		}
350 		mtu3_writel(mbase, USB_QMU_TQCSR(epnum), QMU_Q_START);
351 
352 	} else {
353 		write_rxq_start_addr(mbase, epnum, ring->dma);
354 		mtu3_setbits(mbase, MU3D_EP_RXCR0(epnum), RX_DMAREQEN);
355 		/* don't expect ZLP */
356 		mtu3_clrbits(mbase, U3D_QCR3, QMU_RX_ZLP(epnum));
357 		/* move to next GPD when receive ZLP */
358 		mtu3_setbits(mbase, U3D_QCR3, QMU_RX_COZ(epnum));
359 		mtu3_writel(mbase, U3D_RQERRIESR0,
360 				QMU_RX_LEN_ERR(epnum) | QMU_RX_CS_ERR(epnum));
361 		mtu3_writel(mbase, U3D_RQERRIESR1, QMU_RX_ZLP_ERR(epnum));
362 
363 		if (mtu3_readl(mbase, USB_QMU_RQCSR(epnum)) & QMU_Q_ACTIVE) {
364 			dev_warn(mtu->dev, "Rx %d Active Now!\n", epnum);
365 			return 0;
366 		}
367 		mtu3_writel(mbase, USB_QMU_RQCSR(epnum), QMU_Q_START);
368 	}
369 
370 	return 0;
371 }
372 
373 /* may called in atomic context */
374 void mtu3_qmu_stop(struct mtu3_ep *mep)
375 {
376 	struct mtu3 *mtu = mep->mtu;
377 	void __iomem *mbase = mtu->mac_base;
378 	int epnum = mep->epnum;
379 	u32 value = 0;
380 	u32 qcsr;
381 	int ret;
382 
383 	qcsr = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
384 
385 	if (!(mtu3_readl(mbase, qcsr) & QMU_Q_ACTIVE)) {
386 		dev_dbg(mtu->dev, "%s's qmu is inactive now!\n", mep->name);
387 		return;
388 	}
389 	mtu3_writel(mbase, qcsr, QMU_Q_STOP);
390 
391 	if (mep->is_in)
392 		mtu3_setbits(mbase, MU3D_EP_TXCR0(epnum), TX_FLUSHFIFO);
393 
394 	ret = readl_poll_timeout_atomic(mbase + qcsr, value,
395 			!(value & QMU_Q_ACTIVE), 1, 1000);
396 	if (ret) {
397 		dev_err(mtu->dev, "stop %s's qmu failed\n", mep->name);
398 		return;
399 	}
400 
401 	/* flush fifo again to make sure the fifo is empty */
402 	if (mep->is_in)
403 		mtu3_setbits(mbase, MU3D_EP_TXCR0(epnum), TX_FLUSHFIFO);
404 
405 	dev_dbg(mtu->dev, "%s's qmu stop now!\n", mep->name);
406 }
407 
408 void mtu3_qmu_flush(struct mtu3_ep *mep)
409 {
410 
411 	dev_dbg(mep->mtu->dev, "%s flush QMU %s\n", __func__,
412 		((mep->is_in) ? "TX" : "RX"));
413 
414 	/*Stop QMU */
415 	mtu3_qmu_stop(mep);
416 	reset_gpd_list(mep);
417 }
418 
419 /*
420  * QMU can't transfer zero length packet directly (a hardware limit
421  * on old SoCs), so when needs to send ZLP, we intentionally trigger
422  * a length error interrupt, and in the ISR sends a ZLP by BMU.
423  */
424 static void qmu_tx_zlp_error_handler(struct mtu3 *mtu, u8 epnum)
425 {
426 	struct mtu3_ep *mep = mtu->in_eps + epnum;
427 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
428 	void __iomem *mbase = mtu->mac_base;
429 	struct qmu_gpd *gpd_current = NULL;
430 	struct mtu3_request *mreq;
431 	dma_addr_t cur_gpd_dma;
432 	u32 txcsr = 0;
433 	int ret;
434 
435 	mreq = next_request(mep);
436 	if (mreq && mreq->request.length != 0)
437 		return;
438 
439 	cur_gpd_dma = read_txq_cur_addr(mbase, epnum);
440 	gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
441 
442 	if (GPD_DATA_LEN(mtu, le32_to_cpu(gpd_current->dw3_info)) != 0) {
443 		dev_err(mtu->dev, "TX EP%d buffer length error(!=0)\n", epnum);
444 		return;
445 	}
446 
447 	dev_dbg(mtu->dev, "%s send ZLP for req=%p\n", __func__, mreq);
448 	trace_mtu3_zlp_exp_gpd(mep, gpd_current);
449 
450 	mtu3_clrbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_DMAREQEN);
451 
452 	ret = readl_poll_timeout_atomic(mbase + MU3D_EP_TXCR0(mep->epnum),
453 			txcsr, !(txcsr & TX_FIFOFULL), 1, 1000);
454 	if (ret) {
455 		dev_err(mtu->dev, "%s wait for fifo empty fail\n", __func__);
456 		return;
457 	}
458 	mtu3_setbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_TXPKTRDY);
459 	/* prevent reorder, make sure GPD's HWO is set last */
460 	mb();
461 	/* by pass the current GDP */
462 	gpd_current->dw0_info |= cpu_to_le32(GPD_FLAGS_BPS | GPD_FLAGS_HWO);
463 
464 	/*enable DMAREQEN, switch back to QMU mode */
465 	mtu3_setbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_DMAREQEN);
466 	mtu3_qmu_resume(mep);
467 }
468 
469 /*
470  * NOTE: request list maybe is already empty as following case:
471  * queue_tx --> qmu_interrupt(clear interrupt pending, schedule tasklet)-->
472  * queue_tx --> process_tasklet(meanwhile, the second one is transferred,
473  * tasklet process both of them)-->qmu_interrupt for second one.
474  * To avoid upper case, put qmu_done_tx in ISR directly to process it.
475  */
476 static void qmu_done_tx(struct mtu3 *mtu, u8 epnum)
477 {
478 	struct mtu3_ep *mep = mtu->in_eps + epnum;
479 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
480 	void __iomem *mbase = mtu->mac_base;
481 	struct qmu_gpd *gpd = ring->dequeue;
482 	struct qmu_gpd *gpd_current = NULL;
483 	struct usb_request *request = NULL;
484 	struct mtu3_request *mreq;
485 	dma_addr_t cur_gpd_dma;
486 
487 	/*transfer phy address got from QMU register to virtual address */
488 	cur_gpd_dma = read_txq_cur_addr(mbase, epnum);
489 	gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
490 
491 	dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
492 		__func__, epnum, gpd, gpd_current, ring->enqueue);
493 
494 	while (gpd != gpd_current && !GET_GPD_HWO(gpd)) {
495 
496 		mreq = next_request(mep);
497 
498 		if (mreq == NULL || mreq->gpd != gpd) {
499 			dev_err(mtu->dev, "no correct TX req is found\n");
500 			break;
501 		}
502 
503 		request = &mreq->request;
504 		request->actual = GPD_DATA_LEN(mtu, le32_to_cpu(gpd->dw3_info));
505 		trace_mtu3_complete_gpd(mep, gpd);
506 		mtu3_req_complete(mep, request, 0);
507 
508 		gpd = advance_deq_gpd(ring);
509 	}
510 
511 	dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
512 		__func__, epnum, ring->dequeue, ring->enqueue);
513 
514 }
515 
516 static void qmu_done_rx(struct mtu3 *mtu, u8 epnum)
517 {
518 	struct mtu3_ep *mep = mtu->out_eps + epnum;
519 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
520 	void __iomem *mbase = mtu->mac_base;
521 	struct qmu_gpd *gpd = ring->dequeue;
522 	struct qmu_gpd *gpd_current = NULL;
523 	struct usb_request *req = NULL;
524 	struct mtu3_request *mreq;
525 	dma_addr_t cur_gpd_dma;
526 
527 	cur_gpd_dma = read_rxq_cur_addr(mbase, epnum);
528 	gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
529 
530 	dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
531 		__func__, epnum, gpd, gpd_current, ring->enqueue);
532 
533 	while (gpd != gpd_current && !GET_GPD_HWO(gpd)) {
534 
535 		mreq = next_request(mep);
536 
537 		if (mreq == NULL || mreq->gpd != gpd) {
538 			dev_err(mtu->dev, "no correct RX req is found\n");
539 			break;
540 		}
541 		req = &mreq->request;
542 
543 		req->actual = GPD_DATA_LEN(mtu, le32_to_cpu(gpd->dw3_info));
544 		trace_mtu3_complete_gpd(mep, gpd);
545 		mtu3_req_complete(mep, req, 0);
546 
547 		gpd = advance_deq_gpd(ring);
548 	}
549 
550 	dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
551 		__func__, epnum, ring->dequeue, ring->enqueue);
552 }
553 
554 static void qmu_done_isr(struct mtu3 *mtu, u32 done_status)
555 {
556 	int i;
557 
558 	for (i = 1; i < mtu->num_eps; i++) {
559 		if (done_status & QMU_RX_DONE_INT(i))
560 			qmu_done_rx(mtu, i);
561 		if (done_status & QMU_TX_DONE_INT(i))
562 			qmu_done_tx(mtu, i);
563 	}
564 }
565 
566 static void qmu_exception_isr(struct mtu3 *mtu, u32 qmu_status)
567 {
568 	void __iomem *mbase = mtu->mac_base;
569 	u32 errval;
570 	int i;
571 
572 	if ((qmu_status & RXQ_CSERR_INT) || (qmu_status & RXQ_LENERR_INT)) {
573 		errval = mtu3_readl(mbase, U3D_RQERRIR0);
574 		for (i = 1; i < mtu->num_eps; i++) {
575 			if (errval & QMU_RX_CS_ERR(i))
576 				dev_err(mtu->dev, "Rx %d CS error!\n", i);
577 
578 			if (errval & QMU_RX_LEN_ERR(i))
579 				dev_err(mtu->dev, "RX %d Length error\n", i);
580 		}
581 		mtu3_writel(mbase, U3D_RQERRIR0, errval);
582 	}
583 
584 	if (qmu_status & RXQ_ZLPERR_INT) {
585 		errval = mtu3_readl(mbase, U3D_RQERRIR1);
586 		for (i = 1; i < mtu->num_eps; i++) {
587 			if (errval & QMU_RX_ZLP_ERR(i))
588 				dev_dbg(mtu->dev, "RX EP%d Recv ZLP\n", i);
589 		}
590 		mtu3_writel(mbase, U3D_RQERRIR1, errval);
591 	}
592 
593 	if ((qmu_status & TXQ_CSERR_INT) || (qmu_status & TXQ_LENERR_INT)) {
594 		errval = mtu3_readl(mbase, U3D_TQERRIR0);
595 		for (i = 1; i < mtu->num_eps; i++) {
596 			if (errval & QMU_TX_CS_ERR(i))
597 				dev_err(mtu->dev, "Tx %d checksum error!\n", i);
598 
599 			if (errval & QMU_TX_LEN_ERR(i))
600 				qmu_tx_zlp_error_handler(mtu, i);
601 		}
602 		mtu3_writel(mbase, U3D_TQERRIR0, errval);
603 	}
604 }
605 
606 irqreturn_t mtu3_qmu_isr(struct mtu3 *mtu)
607 {
608 	void __iomem *mbase = mtu->mac_base;
609 	u32 qmu_status;
610 	u32 qmu_done_status;
611 
612 	/* U3D_QISAR1 is read update */
613 	qmu_status = mtu3_readl(mbase, U3D_QISAR1);
614 	qmu_status &= mtu3_readl(mbase, U3D_QIER1);
615 
616 	qmu_done_status = mtu3_readl(mbase, U3D_QISAR0);
617 	qmu_done_status &= mtu3_readl(mbase, U3D_QIER0);
618 	mtu3_writel(mbase, U3D_QISAR0, qmu_done_status); /* W1C */
619 	dev_dbg(mtu->dev, "=== QMUdone[tx=%x, rx=%x] QMUexp[%x] ===\n",
620 		(qmu_done_status & 0xFFFF), qmu_done_status >> 16,
621 		qmu_status);
622 	trace_mtu3_qmu_isr(qmu_done_status, qmu_status);
623 
624 	if (qmu_done_status)
625 		qmu_done_isr(mtu, qmu_done_status);
626 
627 	if (qmu_status)
628 		qmu_exception_isr(mtu, qmu_status);
629 
630 	return IRQ_HANDLED;
631 }
632 
633 int mtu3_qmu_init(struct mtu3 *mtu)
634 {
635 
636 	compiletime_assert(QMU_GPD_SIZE == 16, "QMU_GPD size SHOULD be 16B");
637 
638 	mtu->qmu_gpd_pool = dma_pool_create("QMU_GPD", mtu->dev,
639 			QMU_GPD_RING_SIZE, QMU_GPD_SIZE, 0);
640 
641 	if (!mtu->qmu_gpd_pool)
642 		return -ENOMEM;
643 
644 	return 0;
645 }
646 
647 void mtu3_qmu_exit(struct mtu3 *mtu)
648 {
649 	dma_pool_destroy(mtu->qmu_gpd_pool);
650 }
651