xref: /openbmc/linux/drivers/usb/mtu3/mtu3_qmu.c (revision 4a3fad70)
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 
26 #define QMU_CHECKSUM_LEN	16
27 
28 #define GPD_FLAGS_HWO	BIT(0)
29 #define GPD_FLAGS_BDP	BIT(1)
30 #define GPD_FLAGS_BPS	BIT(2)
31 #define GPD_FLAGS_IOC	BIT(7)
32 
33 #define GPD_EXT_FLAG_ZLP	BIT(5)
34 #define GPD_EXT_NGP(x)		(((x) & 0xf) << 4)
35 #define GPD_EXT_BUF(x)		(((x) & 0xf) << 0)
36 
37 #define HILO_GEN64(hi, lo) (((u64)(hi) << 32) + (lo))
38 #define HILO_DMA(hi, lo)	\
39 	((dma_addr_t)HILO_GEN64((le32_to_cpu(hi)), (le32_to_cpu(lo))))
40 
41 static dma_addr_t read_txq_cur_addr(void __iomem *mbase, u8 epnum)
42 {
43 	u32 txcpr;
44 	u32 txhiar;
45 
46 	txcpr = mtu3_readl(mbase, USB_QMU_TQCPR(epnum));
47 	txhiar = mtu3_readl(mbase, USB_QMU_TQHIAR(epnum));
48 
49 	return HILO_DMA(QMU_CUR_GPD_ADDR_HI(txhiar), txcpr);
50 }
51 
52 static dma_addr_t read_rxq_cur_addr(void __iomem *mbase, u8 epnum)
53 {
54 	u32 rxcpr;
55 	u32 rxhiar;
56 
57 	rxcpr = mtu3_readl(mbase, USB_QMU_RQCPR(epnum));
58 	rxhiar = mtu3_readl(mbase, USB_QMU_RQHIAR(epnum));
59 
60 	return HILO_DMA(QMU_CUR_GPD_ADDR_HI(rxhiar), rxcpr);
61 }
62 
63 static void write_txq_start_addr(void __iomem *mbase, u8 epnum, dma_addr_t dma)
64 {
65 	u32 tqhiar;
66 
67 	mtu3_writel(mbase, USB_QMU_TQSAR(epnum),
68 		    cpu_to_le32(lower_32_bits(dma)));
69 	tqhiar = mtu3_readl(mbase, USB_QMU_TQHIAR(epnum));
70 	tqhiar &= ~QMU_START_ADDR_HI_MSK;
71 	tqhiar |= QMU_START_ADDR_HI(upper_32_bits(dma));
72 	mtu3_writel(mbase, USB_QMU_TQHIAR(epnum), tqhiar);
73 }
74 
75 static void write_rxq_start_addr(void __iomem *mbase, u8 epnum, dma_addr_t dma)
76 {
77 	u32 rqhiar;
78 
79 	mtu3_writel(mbase, USB_QMU_RQSAR(epnum),
80 		    cpu_to_le32(lower_32_bits(dma)));
81 	rqhiar = mtu3_readl(mbase, USB_QMU_RQHIAR(epnum));
82 	rqhiar &= ~QMU_START_ADDR_HI_MSK;
83 	rqhiar |= QMU_START_ADDR_HI(upper_32_bits(dma));
84 	mtu3_writel(mbase, USB_QMU_RQHIAR(epnum), rqhiar);
85 }
86 
87 static struct qmu_gpd *gpd_dma_to_virt(struct mtu3_gpd_ring *ring,
88 		dma_addr_t dma_addr)
89 {
90 	dma_addr_t dma_base = ring->dma;
91 	struct qmu_gpd *gpd_head = ring->start;
92 	u32 offset = (dma_addr - dma_base) / sizeof(*gpd_head);
93 
94 	if (offset >= MAX_GPD_NUM)
95 		return NULL;
96 
97 	return gpd_head + offset;
98 }
99 
100 static dma_addr_t gpd_virt_to_dma(struct mtu3_gpd_ring *ring,
101 		struct qmu_gpd *gpd)
102 {
103 	dma_addr_t dma_base = ring->dma;
104 	struct qmu_gpd *gpd_head = ring->start;
105 	u32 offset;
106 
107 	offset = gpd - gpd_head;
108 	if (offset >= MAX_GPD_NUM)
109 		return 0;
110 
111 	return dma_base + (offset * sizeof(*gpd));
112 }
113 
114 static void gpd_ring_init(struct mtu3_gpd_ring *ring, struct qmu_gpd *gpd)
115 {
116 	ring->start = gpd;
117 	ring->enqueue = gpd;
118 	ring->dequeue = gpd;
119 	ring->end = gpd + MAX_GPD_NUM - 1;
120 }
121 
122 static void reset_gpd_list(struct mtu3_ep *mep)
123 {
124 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
125 	struct qmu_gpd *gpd = ring->start;
126 
127 	if (gpd) {
128 		gpd->flag &= ~GPD_FLAGS_HWO;
129 		gpd_ring_init(ring, gpd);
130 	}
131 }
132 
133 int mtu3_gpd_ring_alloc(struct mtu3_ep *mep)
134 {
135 	struct qmu_gpd *gpd;
136 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
137 
138 	/* software own all gpds as default */
139 	gpd = dma_pool_zalloc(mep->mtu->qmu_gpd_pool, GFP_ATOMIC, &ring->dma);
140 	if (gpd == NULL)
141 		return -ENOMEM;
142 
143 	gpd_ring_init(ring, gpd);
144 
145 	return 0;
146 }
147 
148 void mtu3_gpd_ring_free(struct mtu3_ep *mep)
149 {
150 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
151 
152 	dma_pool_free(mep->mtu->qmu_gpd_pool,
153 			ring->start, ring->dma);
154 	memset(ring, 0, sizeof(*ring));
155 }
156 
157 /*
158  * calculate check sum of a gpd or bd
159  * add "noinline" and "mb" to prevent wrong calculation
160  */
161 static noinline u8 qmu_calc_checksum(u8 *data)
162 {
163 	u8 chksum = 0;
164 	int i;
165 
166 	data[1] = 0x0;  /* set checksum to 0 */
167 
168 	mb();	/* ensure the gpd/bd is really up-to-date */
169 	for (i = 0; i < QMU_CHECKSUM_LEN; i++)
170 		chksum += data[i];
171 
172 	/* Default: HWO=1, @flag[bit0] */
173 	chksum += 1;
174 
175 	return 0xFF - chksum;
176 }
177 
178 void mtu3_qmu_resume(struct mtu3_ep *mep)
179 {
180 	struct mtu3 *mtu = mep->mtu;
181 	void __iomem *mbase = mtu->mac_base;
182 	int epnum = mep->epnum;
183 	u32 offset;
184 
185 	offset = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
186 
187 	mtu3_writel(mbase, offset, QMU_Q_RESUME);
188 	if (!(mtu3_readl(mbase, offset) & QMU_Q_ACTIVE))
189 		mtu3_writel(mbase, offset, QMU_Q_RESUME);
190 }
191 
192 static struct qmu_gpd *advance_enq_gpd(struct mtu3_gpd_ring *ring)
193 {
194 	if (ring->enqueue < ring->end)
195 		ring->enqueue++;
196 	else
197 		ring->enqueue = ring->start;
198 
199 	return ring->enqueue;
200 }
201 
202 static struct qmu_gpd *advance_deq_gpd(struct mtu3_gpd_ring *ring)
203 {
204 	if (ring->dequeue < ring->end)
205 		ring->dequeue++;
206 	else
207 		ring->dequeue = ring->start;
208 
209 	return ring->dequeue;
210 }
211 
212 /* check if a ring is emtpy */
213 static int gpd_ring_empty(struct mtu3_gpd_ring *ring)
214 {
215 	struct qmu_gpd *enq = ring->enqueue;
216 	struct qmu_gpd *next;
217 
218 	if (ring->enqueue < ring->end)
219 		next = enq + 1;
220 	else
221 		next = ring->start;
222 
223 	/* one gpd is reserved to simplify gpd preparation */
224 	return next == ring->dequeue;
225 }
226 
227 int mtu3_prepare_transfer(struct mtu3_ep *mep)
228 {
229 	return gpd_ring_empty(&mep->gpd_ring);
230 }
231 
232 static int mtu3_prepare_tx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
233 {
234 	struct qmu_gpd *enq;
235 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
236 	struct qmu_gpd *gpd = ring->enqueue;
237 	struct usb_request *req = &mreq->request;
238 	dma_addr_t enq_dma;
239 	u16 ext_addr;
240 
241 	/* set all fields to zero as default value */
242 	memset(gpd, 0, sizeof(*gpd));
243 
244 	gpd->buffer = cpu_to_le32(lower_32_bits(req->dma));
245 	ext_addr = GPD_EXT_BUF(upper_32_bits(req->dma));
246 	gpd->buf_len = cpu_to_le16(req->length);
247 	gpd->flag |= GPD_FLAGS_IOC;
248 
249 	/* get the next GPD */
250 	enq = advance_enq_gpd(ring);
251 	enq_dma = gpd_virt_to_dma(ring, enq);
252 	dev_dbg(mep->mtu->dev, "TX-EP%d queue gpd=%p, enq=%p, qdma=%pad\n",
253 		mep->epnum, gpd, enq, &enq_dma);
254 
255 	enq->flag &= ~GPD_FLAGS_HWO;
256 	gpd->next_gpd = cpu_to_le32(lower_32_bits(enq_dma));
257 	ext_addr |= GPD_EXT_NGP(upper_32_bits(enq_dma));
258 	gpd->tx_ext_addr = cpu_to_le16(ext_addr);
259 
260 	if (req->zero)
261 		gpd->ext_flag |= GPD_EXT_FLAG_ZLP;
262 
263 	gpd->chksum = qmu_calc_checksum((u8 *)gpd);
264 	gpd->flag |= GPD_FLAGS_HWO;
265 
266 	mreq->gpd = gpd;
267 
268 	return 0;
269 }
270 
271 static int mtu3_prepare_rx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
272 {
273 	struct qmu_gpd *enq;
274 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
275 	struct qmu_gpd *gpd = ring->enqueue;
276 	struct usb_request *req = &mreq->request;
277 	dma_addr_t enq_dma;
278 	u16 ext_addr;
279 
280 	/* set all fields to zero as default value */
281 	memset(gpd, 0, sizeof(*gpd));
282 
283 	gpd->buffer = cpu_to_le32(lower_32_bits(req->dma));
284 	ext_addr = GPD_EXT_BUF(upper_32_bits(req->dma));
285 	gpd->data_buf_len = cpu_to_le16(req->length);
286 	gpd->flag |= GPD_FLAGS_IOC;
287 
288 	/* get the next GPD */
289 	enq = advance_enq_gpd(ring);
290 	enq_dma = gpd_virt_to_dma(ring, enq);
291 	dev_dbg(mep->mtu->dev, "RX-EP%d queue gpd=%p, enq=%p, qdma=%pad\n",
292 		mep->epnum, gpd, enq, &enq_dma);
293 
294 	enq->flag &= ~GPD_FLAGS_HWO;
295 	gpd->next_gpd = cpu_to_le32(lower_32_bits(enq_dma));
296 	ext_addr |= GPD_EXT_NGP(upper_32_bits(enq_dma));
297 	gpd->rx_ext_addr = cpu_to_le16(ext_addr);
298 	gpd->chksum = qmu_calc_checksum((u8 *)gpd);
299 	gpd->flag |= GPD_FLAGS_HWO;
300 
301 	mreq->gpd = gpd;
302 
303 	return 0;
304 }
305 
306 void mtu3_insert_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
307 {
308 
309 	if (mep->is_in)
310 		mtu3_prepare_tx_gpd(mep, mreq);
311 	else
312 		mtu3_prepare_rx_gpd(mep, mreq);
313 }
314 
315 int mtu3_qmu_start(struct mtu3_ep *mep)
316 {
317 	struct mtu3 *mtu = mep->mtu;
318 	void __iomem *mbase = mtu->mac_base;
319 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
320 	u8 epnum = mep->epnum;
321 
322 	if (mep->is_in) {
323 		/* set QMU start address */
324 		write_txq_start_addr(mbase, epnum, ring->dma);
325 		mtu3_setbits(mbase, MU3D_EP_TXCR0(epnum), TX_DMAREQEN);
326 		mtu3_setbits(mbase, U3D_QCR0, QMU_TX_CS_EN(epnum));
327 		/* send zero length packet according to ZLP flag in GPD */
328 		mtu3_setbits(mbase, U3D_QCR1, QMU_TX_ZLP(epnum));
329 		mtu3_writel(mbase, U3D_TQERRIESR0,
330 				QMU_TX_LEN_ERR(epnum) | QMU_TX_CS_ERR(epnum));
331 
332 		if (mtu3_readl(mbase, USB_QMU_TQCSR(epnum)) & QMU_Q_ACTIVE) {
333 			dev_warn(mtu->dev, "Tx %d Active Now!\n", epnum);
334 			return 0;
335 		}
336 		mtu3_writel(mbase, USB_QMU_TQCSR(epnum), QMU_Q_START);
337 
338 	} else {
339 		write_rxq_start_addr(mbase, epnum, ring->dma);
340 		mtu3_setbits(mbase, MU3D_EP_RXCR0(epnum), RX_DMAREQEN);
341 		mtu3_setbits(mbase, U3D_QCR0, QMU_RX_CS_EN(epnum));
342 		/* don't expect ZLP */
343 		mtu3_clrbits(mbase, U3D_QCR3, QMU_RX_ZLP(epnum));
344 		/* move to next GPD when receive ZLP */
345 		mtu3_setbits(mbase, U3D_QCR3, QMU_RX_COZ(epnum));
346 		mtu3_writel(mbase, U3D_RQERRIESR0,
347 				QMU_RX_LEN_ERR(epnum) | QMU_RX_CS_ERR(epnum));
348 		mtu3_writel(mbase, U3D_RQERRIESR1, QMU_RX_ZLP_ERR(epnum));
349 
350 		if (mtu3_readl(mbase, USB_QMU_RQCSR(epnum)) & QMU_Q_ACTIVE) {
351 			dev_warn(mtu->dev, "Rx %d Active Now!\n", epnum);
352 			return 0;
353 		}
354 		mtu3_writel(mbase, USB_QMU_RQCSR(epnum), QMU_Q_START);
355 	}
356 
357 	return 0;
358 }
359 
360 /* may called in atomic context */
361 void mtu3_qmu_stop(struct mtu3_ep *mep)
362 {
363 	struct mtu3 *mtu = mep->mtu;
364 	void __iomem *mbase = mtu->mac_base;
365 	int epnum = mep->epnum;
366 	u32 value = 0;
367 	u32 qcsr;
368 	int ret;
369 
370 	qcsr = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
371 
372 	if (!(mtu3_readl(mbase, qcsr) & QMU_Q_ACTIVE)) {
373 		dev_dbg(mtu->dev, "%s's qmu is inactive now!\n", mep->name);
374 		return;
375 	}
376 	mtu3_writel(mbase, qcsr, QMU_Q_STOP);
377 
378 	ret = readl_poll_timeout_atomic(mbase + qcsr, value,
379 			!(value & QMU_Q_ACTIVE), 1, 1000);
380 	if (ret) {
381 		dev_err(mtu->dev, "stop %s's qmu failed\n", mep->name);
382 		return;
383 	}
384 
385 	dev_dbg(mtu->dev, "%s's qmu stop now!\n", mep->name);
386 }
387 
388 void mtu3_qmu_flush(struct mtu3_ep *mep)
389 {
390 
391 	dev_dbg(mep->mtu->dev, "%s flush QMU %s\n", __func__,
392 		((mep->is_in) ? "TX" : "RX"));
393 
394 	/*Stop QMU */
395 	mtu3_qmu_stop(mep);
396 	reset_gpd_list(mep);
397 }
398 
399 /*
400  * QMU can't transfer zero length packet directly (a hardware limit
401  * on old SoCs), so when needs to send ZLP, we intentionally trigger
402  * a length error interrupt, and in the ISR sends a ZLP by BMU.
403  */
404 static void qmu_tx_zlp_error_handler(struct mtu3 *mtu, u8 epnum)
405 {
406 	struct mtu3_ep *mep = mtu->in_eps + epnum;
407 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
408 	void __iomem *mbase = mtu->mac_base;
409 	struct qmu_gpd *gpd_current = NULL;
410 	struct usb_request *req = NULL;
411 	struct mtu3_request *mreq;
412 	dma_addr_t cur_gpd_dma;
413 	u32 txcsr = 0;
414 	int ret;
415 
416 	mreq = next_request(mep);
417 	if (mreq && mreq->request.length == 0)
418 		req = &mreq->request;
419 	else
420 		return;
421 
422 	cur_gpd_dma = read_txq_cur_addr(mbase, epnum);
423 	gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
424 
425 	if (le16_to_cpu(gpd_current->buf_len) != 0) {
426 		dev_err(mtu->dev, "TX EP%d buffer length error(!=0)\n", epnum);
427 		return;
428 	}
429 
430 	dev_dbg(mtu->dev, "%s send ZLP for req=%p\n", __func__, mreq);
431 
432 	mtu3_clrbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_DMAREQEN);
433 
434 	ret = readl_poll_timeout_atomic(mbase + MU3D_EP_TXCR0(mep->epnum),
435 			txcsr, !(txcsr & TX_FIFOFULL), 1, 1000);
436 	if (ret) {
437 		dev_err(mtu->dev, "%s wait for fifo empty fail\n", __func__);
438 		return;
439 	}
440 	mtu3_setbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_TXPKTRDY);
441 
442 	/* by pass the current GDP */
443 	gpd_current->flag |= GPD_FLAGS_BPS;
444 	gpd_current->chksum = qmu_calc_checksum((u8 *)gpd_current);
445 	gpd_current->flag |= GPD_FLAGS_HWO;
446 
447 	/*enable DMAREQEN, switch back to QMU mode */
448 	mtu3_setbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_DMAREQEN);
449 	mtu3_qmu_resume(mep);
450 }
451 
452 /*
453  * NOTE: request list maybe is already empty as following case:
454  * queue_tx --> qmu_interrupt(clear interrupt pending, schedule tasklet)-->
455  * queue_tx --> process_tasklet(meanwhile, the second one is transferred,
456  * tasklet process both of them)-->qmu_interrupt for second one.
457  * To avoid upper case, put qmu_done_tx in ISR directly to process it.
458  */
459 static void qmu_done_tx(struct mtu3 *mtu, u8 epnum)
460 {
461 	struct mtu3_ep *mep = mtu->in_eps + epnum;
462 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
463 	void __iomem *mbase = mtu->mac_base;
464 	struct qmu_gpd *gpd = ring->dequeue;
465 	struct qmu_gpd *gpd_current = NULL;
466 	struct usb_request *request = NULL;
467 	struct mtu3_request *mreq;
468 	dma_addr_t cur_gpd_dma;
469 
470 	/*transfer phy address got from QMU register to virtual address */
471 	cur_gpd_dma = read_txq_cur_addr(mbase, epnum);
472 	gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
473 
474 	dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
475 		__func__, epnum, gpd, gpd_current, ring->enqueue);
476 
477 	while (gpd != gpd_current && !(gpd->flag & GPD_FLAGS_HWO)) {
478 
479 		mreq = next_request(mep);
480 
481 		if (mreq == NULL || mreq->gpd != gpd) {
482 			dev_err(mtu->dev, "no correct TX req is found\n");
483 			break;
484 		}
485 
486 		request = &mreq->request;
487 		request->actual = le16_to_cpu(gpd->buf_len);
488 		mtu3_req_complete(mep, request, 0);
489 
490 		gpd = advance_deq_gpd(ring);
491 	}
492 
493 	dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
494 		__func__, epnum, ring->dequeue, ring->enqueue);
495 
496 }
497 
498 static void qmu_done_rx(struct mtu3 *mtu, u8 epnum)
499 {
500 	struct mtu3_ep *mep = mtu->out_eps + epnum;
501 	struct mtu3_gpd_ring *ring = &mep->gpd_ring;
502 	void __iomem *mbase = mtu->mac_base;
503 	struct qmu_gpd *gpd = ring->dequeue;
504 	struct qmu_gpd *gpd_current = NULL;
505 	struct usb_request *req = NULL;
506 	struct mtu3_request *mreq;
507 	dma_addr_t cur_gpd_dma;
508 
509 	cur_gpd_dma = read_rxq_cur_addr(mbase, epnum);
510 	gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
511 
512 	dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
513 		__func__, epnum, gpd, gpd_current, ring->enqueue);
514 
515 	while (gpd != gpd_current && !(gpd->flag & GPD_FLAGS_HWO)) {
516 
517 		mreq = next_request(mep);
518 
519 		if (mreq == NULL || mreq->gpd != gpd) {
520 			dev_err(mtu->dev, "no correct RX req is found\n");
521 			break;
522 		}
523 		req = &mreq->request;
524 
525 		req->actual = le16_to_cpu(gpd->buf_len);
526 		mtu3_req_complete(mep, req, 0);
527 
528 		gpd = advance_deq_gpd(ring);
529 	}
530 
531 	dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
532 		__func__, epnum, ring->dequeue, ring->enqueue);
533 }
534 
535 static void qmu_done_isr(struct mtu3 *mtu, u32 done_status)
536 {
537 	int i;
538 
539 	for (i = 1; i < mtu->num_eps; i++) {
540 		if (done_status & QMU_RX_DONE_INT(i))
541 			qmu_done_rx(mtu, i);
542 		if (done_status & QMU_TX_DONE_INT(i))
543 			qmu_done_tx(mtu, i);
544 	}
545 }
546 
547 static void qmu_exception_isr(struct mtu3 *mtu, u32 qmu_status)
548 {
549 	void __iomem *mbase = mtu->mac_base;
550 	u32 errval;
551 	int i;
552 
553 	if ((qmu_status & RXQ_CSERR_INT) || (qmu_status & RXQ_LENERR_INT)) {
554 		errval = mtu3_readl(mbase, U3D_RQERRIR0);
555 		for (i = 1; i < mtu->num_eps; i++) {
556 			if (errval & QMU_RX_CS_ERR(i))
557 				dev_err(mtu->dev, "Rx %d CS error!\n", i);
558 
559 			if (errval & QMU_RX_LEN_ERR(i))
560 				dev_err(mtu->dev, "RX %d Length error\n", i);
561 		}
562 		mtu3_writel(mbase, U3D_RQERRIR0, errval);
563 	}
564 
565 	if (qmu_status & RXQ_ZLPERR_INT) {
566 		errval = mtu3_readl(mbase, U3D_RQERRIR1);
567 		for (i = 1; i < mtu->num_eps; i++) {
568 			if (errval & QMU_RX_ZLP_ERR(i))
569 				dev_dbg(mtu->dev, "RX EP%d Recv ZLP\n", i);
570 		}
571 		mtu3_writel(mbase, U3D_RQERRIR1, errval);
572 	}
573 
574 	if ((qmu_status & TXQ_CSERR_INT) || (qmu_status & TXQ_LENERR_INT)) {
575 		errval = mtu3_readl(mbase, U3D_TQERRIR0);
576 		for (i = 1; i < mtu->num_eps; i++) {
577 			if (errval & QMU_TX_CS_ERR(i))
578 				dev_err(mtu->dev, "Tx %d checksum error!\n", i);
579 
580 			if (errval & QMU_TX_LEN_ERR(i))
581 				qmu_tx_zlp_error_handler(mtu, i);
582 		}
583 		mtu3_writel(mbase, U3D_TQERRIR0, errval);
584 	}
585 }
586 
587 irqreturn_t mtu3_qmu_isr(struct mtu3 *mtu)
588 {
589 	void __iomem *mbase = mtu->mac_base;
590 	u32 qmu_status;
591 	u32 qmu_done_status;
592 
593 	/* U3D_QISAR1 is read update */
594 	qmu_status = mtu3_readl(mbase, U3D_QISAR1);
595 	qmu_status &= mtu3_readl(mbase, U3D_QIER1);
596 
597 	qmu_done_status = mtu3_readl(mbase, U3D_QISAR0);
598 	qmu_done_status &= mtu3_readl(mbase, U3D_QIER0);
599 	mtu3_writel(mbase, U3D_QISAR0, qmu_done_status); /* W1C */
600 	dev_dbg(mtu->dev, "=== QMUdone[tx=%x, rx=%x] QMUexp[%x] ===\n",
601 		(qmu_done_status & 0xFFFF), qmu_done_status >> 16,
602 		qmu_status);
603 
604 	if (qmu_done_status)
605 		qmu_done_isr(mtu, qmu_done_status);
606 
607 	if (qmu_status)
608 		qmu_exception_isr(mtu, qmu_status);
609 
610 	return IRQ_HANDLED;
611 }
612 
613 int mtu3_qmu_init(struct mtu3 *mtu)
614 {
615 
616 	compiletime_assert(QMU_GPD_SIZE == 16, "QMU_GPD size SHOULD be 16B");
617 
618 	mtu->qmu_gpd_pool = dma_pool_create("QMU_GPD", mtu->dev,
619 			QMU_GPD_RING_SIZE, QMU_GPD_SIZE, 0);
620 
621 	if (!mtu->qmu_gpd_pool)
622 		return -ENOMEM;
623 
624 	return 0;
625 }
626 
627 void mtu3_qmu_exit(struct mtu3 *mtu)
628 {
629 	dma_pool_destroy(mtu->qmu_gpd_pool);
630 }
631