1 // SPDX-License-Identifier: GPL-2.0
3 * mtu3_qmu.c - Queue Management Unit driver for device controller
5 * Copyright (C) 2016 MediaTek Inc.
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.
18 * For more detailed information, please refer to QMU Programming Guide
21 #include <linux/dmapool.h>
22 #include <linux/iopoll.h>
26 #define QMU_CHECKSUM_LEN 16
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)
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)
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))))
41 static dma_addr_t read_txq_cur_addr(void __iomem *mbase, u8 epnum)
46 txcpr = mtu3_readl(mbase, USB_QMU_TQCPR(epnum));
47 txhiar = mtu3_readl(mbase, USB_QMU_TQHIAR(epnum));
49 return HILO_DMA(QMU_CUR_GPD_ADDR_HI(txhiar), txcpr);
52 static dma_addr_t read_rxq_cur_addr(void __iomem *mbase, u8 epnum)
57 rxcpr = mtu3_readl(mbase, USB_QMU_RQCPR(epnum));
58 rxhiar = mtu3_readl(mbase, USB_QMU_RQHIAR(epnum));
60 return HILO_DMA(QMU_CUR_GPD_ADDR_HI(rxhiar), rxcpr);
63 static void write_txq_start_addr(void __iomem *mbase, u8 epnum, dma_addr_t dma)
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);
75 static void write_rxq_start_addr(void __iomem *mbase, u8 epnum, dma_addr_t dma)
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);
87 static struct qmu_gpd *gpd_dma_to_virt(struct mtu3_gpd_ring *ring,
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);
94 if (offset >= MAX_GPD_NUM)
97 return gpd_head + offset;
100 static dma_addr_t gpd_virt_to_dma(struct mtu3_gpd_ring *ring,
103 dma_addr_t dma_base = ring->dma;
104 struct qmu_gpd *gpd_head = ring->start;
107 offset = gpd - gpd_head;
108 if (offset >= MAX_GPD_NUM)
111 return dma_base + (offset * sizeof(*gpd));
114 static void gpd_ring_init(struct mtu3_gpd_ring *ring, struct qmu_gpd *gpd)
119 ring->end = gpd + MAX_GPD_NUM - 1;
122 static void reset_gpd_list(struct mtu3_ep *mep)
124 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
125 struct qmu_gpd *gpd = ring->start;
128 gpd->flag &= ~GPD_FLAGS_HWO;
129 gpd_ring_init(ring, gpd);
133 int mtu3_gpd_ring_alloc(struct mtu3_ep *mep)
136 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
138 /* software own all gpds as default */
139 gpd = dma_pool_zalloc(mep->mtu->qmu_gpd_pool, GFP_ATOMIC, &ring->dma);
143 gpd_ring_init(ring, gpd);
148 void mtu3_gpd_ring_free(struct mtu3_ep *mep)
150 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
152 dma_pool_free(mep->mtu->qmu_gpd_pool,
153 ring->start, ring->dma);
154 memset(ring, 0, sizeof(*ring));
157 void mtu3_qmu_resume(struct mtu3_ep *mep)
159 struct mtu3 *mtu = mep->mtu;
160 void __iomem *mbase = mtu->mac_base;
161 int epnum = mep->epnum;
164 offset = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
166 mtu3_writel(mbase, offset, QMU_Q_RESUME);
167 if (!(mtu3_readl(mbase, offset) & QMU_Q_ACTIVE))
168 mtu3_writel(mbase, offset, QMU_Q_RESUME);
171 static struct qmu_gpd *advance_enq_gpd(struct mtu3_gpd_ring *ring)
173 if (ring->enqueue < ring->end)
176 ring->enqueue = ring->start;
178 return ring->enqueue;
181 static struct qmu_gpd *advance_deq_gpd(struct mtu3_gpd_ring *ring)
183 if (ring->dequeue < ring->end)
186 ring->dequeue = ring->start;
188 return ring->dequeue;
191 /* check if a ring is emtpy */
192 static int gpd_ring_empty(struct mtu3_gpd_ring *ring)
194 struct qmu_gpd *enq = ring->enqueue;
195 struct qmu_gpd *next;
197 if (ring->enqueue < ring->end)
202 /* one gpd is reserved to simplify gpd preparation */
203 return next == ring->dequeue;
206 int mtu3_prepare_transfer(struct mtu3_ep *mep)
208 return gpd_ring_empty(&mep->gpd_ring);
211 static int mtu3_prepare_tx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
214 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
215 struct qmu_gpd *gpd = ring->enqueue;
216 struct usb_request *req = &mreq->request;
220 /* set all fields to zero as default value */
221 memset(gpd, 0, sizeof(*gpd));
223 gpd->buffer = cpu_to_le32(lower_32_bits(req->dma));
224 ext_addr = GPD_EXT_BUF(upper_32_bits(req->dma));
225 gpd->buf_len = cpu_to_le16(req->length);
226 gpd->flag |= GPD_FLAGS_IOC;
228 /* get the next GPD */
229 enq = advance_enq_gpd(ring);
230 enq_dma = gpd_virt_to_dma(ring, enq);
231 dev_dbg(mep->mtu->dev, "TX-EP%d queue gpd=%p, enq=%p, qdma=%pad\n",
232 mep->epnum, gpd, enq, &enq_dma);
234 enq->flag &= ~GPD_FLAGS_HWO;
235 gpd->next_gpd = cpu_to_le32(lower_32_bits(enq_dma));
236 ext_addr |= GPD_EXT_NGP(upper_32_bits(enq_dma));
237 gpd->tx_ext_addr = cpu_to_le16(ext_addr);
240 gpd->ext_flag |= GPD_EXT_FLAG_ZLP;
242 gpd->flag |= GPD_FLAGS_HWO;
249 static int mtu3_prepare_rx_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
252 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
253 struct qmu_gpd *gpd = ring->enqueue;
254 struct usb_request *req = &mreq->request;
258 /* set all fields to zero as default value */
259 memset(gpd, 0, sizeof(*gpd));
261 gpd->buffer = cpu_to_le32(lower_32_bits(req->dma));
262 ext_addr = GPD_EXT_BUF(upper_32_bits(req->dma));
263 gpd->data_buf_len = cpu_to_le16(req->length);
264 gpd->flag |= GPD_FLAGS_IOC;
266 /* get the next GPD */
267 enq = advance_enq_gpd(ring);
268 enq_dma = gpd_virt_to_dma(ring, enq);
269 dev_dbg(mep->mtu->dev, "RX-EP%d queue gpd=%p, enq=%p, qdma=%pad\n",
270 mep->epnum, gpd, enq, &enq_dma);
272 enq->flag &= ~GPD_FLAGS_HWO;
273 gpd->next_gpd = cpu_to_le32(lower_32_bits(enq_dma));
274 ext_addr |= GPD_EXT_NGP(upper_32_bits(enq_dma));
275 gpd->rx_ext_addr = cpu_to_le16(ext_addr);
276 gpd->flag |= GPD_FLAGS_HWO;
283 void mtu3_insert_gpd(struct mtu3_ep *mep, struct mtu3_request *mreq)
287 mtu3_prepare_tx_gpd(mep, mreq);
289 mtu3_prepare_rx_gpd(mep, mreq);
292 int mtu3_qmu_start(struct mtu3_ep *mep)
294 struct mtu3 *mtu = mep->mtu;
295 void __iomem *mbase = mtu->mac_base;
296 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
297 u8 epnum = mep->epnum;
300 /* set QMU start address */
301 write_txq_start_addr(mbase, epnum, ring->dma);
302 mtu3_setbits(mbase, MU3D_EP_TXCR0(epnum), TX_DMAREQEN);
303 /* send zero length packet according to ZLP flag in GPD */
304 mtu3_setbits(mbase, U3D_QCR1, QMU_TX_ZLP(epnum));
305 mtu3_writel(mbase, U3D_TQERRIESR0,
306 QMU_TX_LEN_ERR(epnum) | QMU_TX_CS_ERR(epnum));
308 if (mtu3_readl(mbase, USB_QMU_TQCSR(epnum)) & QMU_Q_ACTIVE) {
309 dev_warn(mtu->dev, "Tx %d Active Now!\n", epnum);
312 mtu3_writel(mbase, USB_QMU_TQCSR(epnum), QMU_Q_START);
315 write_rxq_start_addr(mbase, epnum, ring->dma);
316 mtu3_setbits(mbase, MU3D_EP_RXCR0(epnum), RX_DMAREQEN);
317 /* don't expect ZLP */
318 mtu3_clrbits(mbase, U3D_QCR3, QMU_RX_ZLP(epnum));
319 /* move to next GPD when receive ZLP */
320 mtu3_setbits(mbase, U3D_QCR3, QMU_RX_COZ(epnum));
321 mtu3_writel(mbase, U3D_RQERRIESR0,
322 QMU_RX_LEN_ERR(epnum) | QMU_RX_CS_ERR(epnum));
323 mtu3_writel(mbase, U3D_RQERRIESR1, QMU_RX_ZLP_ERR(epnum));
325 if (mtu3_readl(mbase, USB_QMU_RQCSR(epnum)) & QMU_Q_ACTIVE) {
326 dev_warn(mtu->dev, "Rx %d Active Now!\n", epnum);
329 mtu3_writel(mbase, USB_QMU_RQCSR(epnum), QMU_Q_START);
335 /* may called in atomic context */
336 void mtu3_qmu_stop(struct mtu3_ep *mep)
338 struct mtu3 *mtu = mep->mtu;
339 void __iomem *mbase = mtu->mac_base;
340 int epnum = mep->epnum;
345 qcsr = mep->is_in ? USB_QMU_TQCSR(epnum) : USB_QMU_RQCSR(epnum);
347 if (!(mtu3_readl(mbase, qcsr) & QMU_Q_ACTIVE)) {
348 dev_dbg(mtu->dev, "%s's qmu is inactive now!\n", mep->name);
351 mtu3_writel(mbase, qcsr, QMU_Q_STOP);
353 ret = readl_poll_timeout_atomic(mbase + qcsr, value,
354 !(value & QMU_Q_ACTIVE), 1, 1000);
356 dev_err(mtu->dev, "stop %s's qmu failed\n", mep->name);
360 dev_dbg(mtu->dev, "%s's qmu stop now!\n", mep->name);
363 void mtu3_qmu_flush(struct mtu3_ep *mep)
366 dev_dbg(mep->mtu->dev, "%s flush QMU %s\n", __func__,
367 ((mep->is_in) ? "TX" : "RX"));
375 * QMU can't transfer zero length packet directly (a hardware limit
376 * on old SoCs), so when needs to send ZLP, we intentionally trigger
377 * a length error interrupt, and in the ISR sends a ZLP by BMU.
379 static void qmu_tx_zlp_error_handler(struct mtu3 *mtu, u8 epnum)
381 struct mtu3_ep *mep = mtu->in_eps + epnum;
382 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
383 void __iomem *mbase = mtu->mac_base;
384 struct qmu_gpd *gpd_current = NULL;
385 struct usb_request *req = NULL;
386 struct mtu3_request *mreq;
387 dma_addr_t cur_gpd_dma;
391 mreq = next_request(mep);
392 if (mreq && mreq->request.length == 0)
393 req = &mreq->request;
397 cur_gpd_dma = read_txq_cur_addr(mbase, epnum);
398 gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
400 if (le16_to_cpu(gpd_current->buf_len) != 0) {
401 dev_err(mtu->dev, "TX EP%d buffer length error(!=0)\n", epnum);
405 dev_dbg(mtu->dev, "%s send ZLP for req=%p\n", __func__, req);
407 mtu3_clrbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_DMAREQEN);
409 ret = readl_poll_timeout_atomic(mbase + MU3D_EP_TXCR0(mep->epnum),
410 txcsr, !(txcsr & TX_FIFOFULL), 1, 1000);
412 dev_err(mtu->dev, "%s wait for fifo empty fail\n", __func__);
415 mtu3_setbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_TXPKTRDY);
417 /* by pass the current GDP */
418 gpd_current->flag |= GPD_FLAGS_BPS;
419 gpd_current->flag |= GPD_FLAGS_HWO;
421 /*enable DMAREQEN, switch back to QMU mode */
422 mtu3_setbits(mbase, MU3D_EP_TXCR0(mep->epnum), TX_DMAREQEN);
423 mtu3_qmu_resume(mep);
427 * NOTE: request list maybe is already empty as following case:
428 * queue_tx --> qmu_interrupt(clear interrupt pending, schedule tasklet)-->
429 * queue_tx --> process_tasklet(meanwhile, the second one is transferred,
430 * tasklet process both of them)-->qmu_interrupt for second one.
431 * To avoid upper case, put qmu_done_tx in ISR directly to process it.
433 static void qmu_done_tx(struct mtu3 *mtu, u8 epnum)
435 struct mtu3_ep *mep = mtu->in_eps + epnum;
436 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
437 void __iomem *mbase = mtu->mac_base;
438 struct qmu_gpd *gpd = ring->dequeue;
439 struct qmu_gpd *gpd_current = NULL;
440 struct usb_request *request = NULL;
441 struct mtu3_request *mreq;
442 dma_addr_t cur_gpd_dma;
444 /*transfer phy address got from QMU register to virtual address */
445 cur_gpd_dma = read_txq_cur_addr(mbase, epnum);
446 gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
448 dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
449 __func__, epnum, gpd, gpd_current, ring->enqueue);
451 while (gpd != gpd_current && !(gpd->flag & GPD_FLAGS_HWO)) {
453 mreq = next_request(mep);
455 if (mreq == NULL || mreq->gpd != gpd) {
456 dev_err(mtu->dev, "no correct TX req is found\n");
460 request = &mreq->request;
461 request->actual = le16_to_cpu(gpd->buf_len);
462 mtu3_req_complete(mep, request, 0);
464 gpd = advance_deq_gpd(ring);
467 dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
468 __func__, epnum, ring->dequeue, ring->enqueue);
472 static void qmu_done_rx(struct mtu3 *mtu, u8 epnum)
474 struct mtu3_ep *mep = mtu->out_eps + epnum;
475 struct mtu3_gpd_ring *ring = &mep->gpd_ring;
476 void __iomem *mbase = mtu->mac_base;
477 struct qmu_gpd *gpd = ring->dequeue;
478 struct qmu_gpd *gpd_current = NULL;
479 struct usb_request *req = NULL;
480 struct mtu3_request *mreq;
481 dma_addr_t cur_gpd_dma;
483 cur_gpd_dma = read_rxq_cur_addr(mbase, epnum);
484 gpd_current = gpd_dma_to_virt(ring, cur_gpd_dma);
486 dev_dbg(mtu->dev, "%s EP%d, last=%p, current=%p, enq=%p\n",
487 __func__, epnum, gpd, gpd_current, ring->enqueue);
489 while (gpd != gpd_current && !(gpd->flag & GPD_FLAGS_HWO)) {
491 mreq = next_request(mep);
493 if (mreq == NULL || mreq->gpd != gpd) {
494 dev_err(mtu->dev, "no correct RX req is found\n");
497 req = &mreq->request;
499 req->actual = le16_to_cpu(gpd->buf_len);
500 mtu3_req_complete(mep, req, 0);
502 gpd = advance_deq_gpd(ring);
505 dev_dbg(mtu->dev, "%s EP%d, deq=%p, enq=%p, complete\n",
506 __func__, epnum, ring->dequeue, ring->enqueue);
509 static void qmu_done_isr(struct mtu3 *mtu, u32 done_status)
513 for (i = 1; i < mtu->num_eps; i++) {
514 if (done_status & QMU_RX_DONE_INT(i))
516 if (done_status & QMU_TX_DONE_INT(i))
521 static void qmu_exception_isr(struct mtu3 *mtu, u32 qmu_status)
523 void __iomem *mbase = mtu->mac_base;
527 if ((qmu_status & RXQ_CSERR_INT) || (qmu_status & RXQ_LENERR_INT)) {
528 errval = mtu3_readl(mbase, U3D_RQERRIR0);
529 for (i = 1; i < mtu->num_eps; i++) {
530 if (errval & QMU_RX_CS_ERR(i))
531 dev_err(mtu->dev, "Rx %d CS error!\n", i);
533 if (errval & QMU_RX_LEN_ERR(i))
534 dev_err(mtu->dev, "RX %d Length error\n", i);
536 mtu3_writel(mbase, U3D_RQERRIR0, errval);
539 if (qmu_status & RXQ_ZLPERR_INT) {
540 errval = mtu3_readl(mbase, U3D_RQERRIR1);
541 for (i = 1; i < mtu->num_eps; i++) {
542 if (errval & QMU_RX_ZLP_ERR(i))
543 dev_dbg(mtu->dev, "RX EP%d Recv ZLP\n", i);
545 mtu3_writel(mbase, U3D_RQERRIR1, errval);
548 if ((qmu_status & TXQ_CSERR_INT) || (qmu_status & TXQ_LENERR_INT)) {
549 errval = mtu3_readl(mbase, U3D_TQERRIR0);
550 for (i = 1; i < mtu->num_eps; i++) {
551 if (errval & QMU_TX_CS_ERR(i))
552 dev_err(mtu->dev, "Tx %d checksum error!\n", i);
554 if (errval & QMU_TX_LEN_ERR(i))
555 qmu_tx_zlp_error_handler(mtu, i);
557 mtu3_writel(mbase, U3D_TQERRIR0, errval);
561 irqreturn_t mtu3_qmu_isr(struct mtu3 *mtu)
563 void __iomem *mbase = mtu->mac_base;
567 /* U3D_QISAR1 is read update */
568 qmu_status = mtu3_readl(mbase, U3D_QISAR1);
569 qmu_status &= mtu3_readl(mbase, U3D_QIER1);
571 qmu_done_status = mtu3_readl(mbase, U3D_QISAR0);
572 qmu_done_status &= mtu3_readl(mbase, U3D_QIER0);
573 mtu3_writel(mbase, U3D_QISAR0, qmu_done_status); /* W1C */
574 dev_dbg(mtu->dev, "=== QMUdone[tx=%x, rx=%x] QMUexp[%x] ===\n",
575 (qmu_done_status & 0xFFFF), qmu_done_status >> 16,
579 qmu_done_isr(mtu, qmu_done_status);
582 qmu_exception_isr(mtu, qmu_status);
587 int mtu3_qmu_init(struct mtu3 *mtu)
590 compiletime_assert(QMU_GPD_SIZE == 16, "QMU_GPD size SHOULD be 16B");
592 mtu->qmu_gpd_pool = dma_pool_create("QMU_GPD", mtu->dev,
593 QMU_GPD_RING_SIZE, QMU_GPD_SIZE, 0);
595 if (!mtu->qmu_gpd_pool)
601 void mtu3_qmu_exit(struct mtu3 *mtu)
603 dma_pool_destroy(mtu->qmu_gpd_pool);