1 // SPDX-License-Identifier: GPL-2.0
3 * TUSB6010 USB 2.0 OTG Dual Role controller OMAP DMA interface
5 * Copyright (C) 2006 Nokia Corporation
6 * Tony Lindgren <tony@atomide.com>
8 #include <linux/module.h>
9 #include <linux/kernel.h>
10 #include <linux/errno.h>
11 #include <linux/usb.h>
12 #include <linux/platform_device.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/slab.h>
15 #include <linux/dmaengine.h>
17 #include "musb_core.h"
20 #define to_chdat(c) ((struct tusb_omap_dma_ch *)(c)->private_data)
22 #define MAX_DMAREQ 5 /* REVISIT: Really 6, but req5 not OK */
24 struct tusb_dma_data {
26 struct dma_chan *chan;
29 struct tusb_omap_dma_ch {
32 unsigned long phys_offset;
35 struct musb_hw_ep *hw_ep;
37 struct tusb_dma_data *dma_data;
39 struct tusb_omap_dma *tusb_dma;
45 u16 transfer_packet_sz;
50 struct tusb_omap_dma {
51 struct dma_controller controller;
54 struct tusb_dma_data dma_pool[MAX_DMAREQ];
55 unsigned multichannel:1;
59 * Allocate dmareq0 to the current channel unless it's already taken
61 static inline int tusb_omap_use_shared_dmareq(struct tusb_omap_dma_ch *chdat)
63 u32 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
66 dev_dbg(chdat->musb->controller, "ep%i dmareq0 is busy for ep%i\n",
67 chdat->epnum, reg & 0xf);
72 reg = (1 << 4) | chdat->epnum;
76 musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
81 static inline void tusb_omap_free_shared_dmareq(struct tusb_omap_dma_ch *chdat)
83 u32 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
85 if ((reg & 0xf) != chdat->epnum) {
86 printk(KERN_ERR "ep%i trying to release dmareq0 for ep%i\n",
87 chdat->epnum, reg & 0xf);
90 musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, 0);
94 * See also musb_dma_completion in plat_uds.c and musb_g_[tx|rx]() in
97 static void tusb_omap_dma_cb(void *data)
99 struct dma_channel *channel = (struct dma_channel *)data;
100 struct tusb_omap_dma_ch *chdat = to_chdat(channel);
101 struct tusb_omap_dma *tusb_dma = chdat->tusb_dma;
102 struct musb *musb = chdat->musb;
103 struct device *dev = musb->controller;
104 struct musb_hw_ep *hw_ep = chdat->hw_ep;
105 void __iomem *ep_conf = hw_ep->conf;
106 void __iomem *mbase = musb->mregs;
107 unsigned long remaining, flags, pio;
109 spin_lock_irqsave(&musb->lock, flags);
111 dev_dbg(musb->controller, "ep%i %s dma callback\n",
112 chdat->epnum, chdat->tx ? "tx" : "rx");
115 remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
117 remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
119 remaining = TUSB_EP_CONFIG_XFR_SIZE(remaining);
121 /* HW issue #10: XFR_SIZE may get corrupt on DMA (both async & sync) */
122 if (unlikely(remaining > chdat->transfer_len)) {
123 dev_dbg(musb->controller, "Corrupt %s XFR_SIZE: 0x%08lx\n",
124 chdat->tx ? "tx" : "rx", remaining);
128 channel->actual_len = chdat->transfer_len - remaining;
129 pio = chdat->len - channel->actual_len;
131 dev_dbg(musb->controller, "DMA remaining %lu/%u\n", remaining, chdat->transfer_len);
133 /* Transfer remaining 1 - 31 bytes */
134 if (pio > 0 && pio < 32) {
137 dev_dbg(musb->controller, "Using PIO for remaining %lu bytes\n", pio);
138 buf = phys_to_virt((u32)chdat->dma_addr) + chdat->transfer_len;
140 dma_unmap_single(dev, chdat->dma_addr,
143 musb_write_fifo(hw_ep, pio, buf);
145 dma_unmap_single(dev, chdat->dma_addr,
148 musb_read_fifo(hw_ep, pio, buf);
150 channel->actual_len += pio;
153 if (!tusb_dma->multichannel)
154 tusb_omap_free_shared_dmareq(chdat);
156 channel->status = MUSB_DMA_STATUS_FREE;
158 musb_dma_completion(musb, chdat->epnum, chdat->tx);
160 /* We must terminate short tx transfers manually by setting TXPKTRDY.
161 * REVISIT: This same problem may occur with other MUSB dma as well.
162 * Easy to test with g_ether by pinging the MUSB board with ping -s54.
164 if ((chdat->transfer_len < chdat->packet_sz)
165 || (chdat->transfer_len % chdat->packet_sz != 0)) {
169 dev_dbg(musb->controller, "terminating short tx packet\n");
170 musb_ep_select(mbase, chdat->epnum);
171 csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
172 csr |= MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY
173 | MUSB_TXCSR_P_WZC_BITS;
174 musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
178 spin_unlock_irqrestore(&musb->lock, flags);
181 static int tusb_omap_dma_program(struct dma_channel *channel, u16 packet_sz,
182 u8 rndis_mode, dma_addr_t dma_addr, u32 len)
184 struct tusb_omap_dma_ch *chdat = to_chdat(channel);
185 struct tusb_omap_dma *tusb_dma = chdat->tusb_dma;
186 struct musb *musb = chdat->musb;
187 struct device *dev = musb->controller;
188 struct musb_hw_ep *hw_ep = chdat->hw_ep;
189 void __iomem *mbase = musb->mregs;
190 void __iomem *ep_conf = hw_ep->conf;
191 dma_addr_t fifo_addr = hw_ep->fifo_sync;
195 struct tusb_dma_data *dma_data;
196 struct dma_async_tx_descriptor *dma_desc;
197 struct dma_slave_config dma_cfg;
198 enum dma_transfer_direction dma_dir;
202 if (unlikely(dma_addr & 0x1) || (len < 32) || (len > packet_sz))
206 * HW issue #10: Async dma will eventually corrupt the XFR_SIZE
207 * register which will cause missed DMA interrupt. We could try to
208 * use a timer for the callback, but it is unsafe as the XFR_SIZE
209 * register is corrupt, and we won't know if the DMA worked.
215 * Because of HW issue #10, it seems like mixing sync DMA and async
216 * PIO access can confuse the DMA. Make sure XFR_SIZE is reset before
217 * using the channel for DMA.
220 dma_remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET);
222 dma_remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET);
224 dma_remaining = TUSB_EP_CONFIG_XFR_SIZE(dma_remaining);
226 dev_dbg(musb->controller, "Busy %s dma, not using: %08x\n",
227 chdat->tx ? "tx" : "rx", dma_remaining);
231 chdat->transfer_len = len & ~0x1f;
234 chdat->transfer_packet_sz = chdat->transfer_len;
236 chdat->transfer_packet_sz = packet_sz;
238 dma_data = chdat->dma_data;
239 if (!tusb_dma->multichannel) {
240 if (tusb_omap_use_shared_dmareq(chdat) != 0) {
241 dev_dbg(musb->controller, "could not get dma for ep%i\n", chdat->epnum);
244 if (dma_data->dmareq < 0) {
245 /* REVISIT: This should get blocked earlier, happens
246 * with MSC ErrorRecoveryTest
253 chdat->packet_sz = packet_sz;
255 channel->actual_len = 0;
256 chdat->dma_addr = dma_addr;
257 channel->status = MUSB_DMA_STATUS_BUSY;
259 /* Since we're recycling dma areas, we need to clean or invalidate */
261 dma_dir = DMA_MEM_TO_DEV;
262 dma_map_single(dev, phys_to_virt(dma_addr), len,
265 dma_dir = DMA_DEV_TO_MEM;
266 dma_map_single(dev, phys_to_virt(dma_addr), len,
270 memset(&dma_cfg, 0, sizeof(dma_cfg));
272 /* Use 16-bit transfer if dma_addr is not 32-bit aligned */
273 if ((dma_addr & 0x3) == 0) {
274 dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
275 dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
278 dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
279 dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
282 fifo_addr = hw_ep->fifo_async;
285 dev_dbg(musb->controller,
286 "ep%i %s dma: %pad len: %u(%u) packet_sz: %i(%i)\n",
287 chdat->epnum, chdat->tx ? "tx" : "rx", &dma_addr,
288 chdat->transfer_len, len, chdat->transfer_packet_sz, packet_sz);
290 dma_cfg.src_addr = fifo_addr;
291 dma_cfg.dst_addr = fifo_addr;
292 dma_cfg.src_port_window_size = port_window;
293 dma_cfg.src_maxburst = port_window;
294 dma_cfg.dst_port_window_size = port_window;
295 dma_cfg.dst_maxburst = port_window;
297 ret = dmaengine_slave_config(dma_data->chan, &dma_cfg);
299 dev_err(musb->controller, "DMA slave config failed: %d\n", ret);
303 dma_desc = dmaengine_prep_slave_single(dma_data->chan, dma_addr,
304 chdat->transfer_len, dma_dir,
305 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
307 dev_err(musb->controller, "DMA prep_slave_single failed\n");
311 dma_desc->callback = tusb_omap_dma_cb;
312 dma_desc->callback_param = channel;
313 dmaengine_submit(dma_desc);
315 dev_dbg(musb->controller,
316 "ep%i %s using %i-bit %s dma from %pad to %pad\n",
317 chdat->epnum, chdat->tx ? "tx" : "rx",
318 dma_cfg.src_addr_width * 8,
319 ((dma_addr & 0x3) == 0) ? "sync" : "async",
320 (dma_dir == DMA_MEM_TO_DEV) ? &dma_addr : &fifo_addr,
321 (dma_dir == DMA_MEM_TO_DEV) ? &fifo_addr : &dma_addr);
324 * Prepare MUSB for DMA transfer
326 musb_ep_select(mbase, chdat->epnum);
328 csr = musb_readw(hw_ep->regs, MUSB_TXCSR);
329 csr |= (MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB
330 | MUSB_TXCSR_DMAMODE | MUSB_TXCSR_MODE);
331 csr &= ~MUSB_TXCSR_P_UNDERRUN;
332 musb_writew(hw_ep->regs, MUSB_TXCSR, csr);
334 csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
335 csr |= MUSB_RXCSR_DMAENAB;
336 csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAMODE);
337 musb_writew(hw_ep->regs, MUSB_RXCSR,
338 csr | MUSB_RXCSR_P_WZC_BITS);
341 /* Start DMA transfer */
342 dma_async_issue_pending(dma_data->chan);
345 /* Send transfer_packet_sz packets at a time */
346 psize = musb_readl(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET);
348 psize |= chdat->transfer_packet_sz;
349 musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET, psize);
351 musb_writel(ep_conf, TUSB_EP_TX_OFFSET,
352 TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
354 /* Receive transfer_packet_sz packets at a time */
355 psize = musb_readl(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET);
356 psize &= ~(0x7ff << 16);
357 psize |= (chdat->transfer_packet_sz << 16);
358 musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET, psize);
360 musb_writel(ep_conf, TUSB_EP_RX_OFFSET,
361 TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len));
367 static int tusb_omap_dma_abort(struct dma_channel *channel)
369 struct tusb_omap_dma_ch *chdat = to_chdat(channel);
372 dmaengine_terminate_all(chdat->dma_data->chan);
374 channel->status = MUSB_DMA_STATUS_FREE;
379 static inline int tusb_omap_dma_allocate_dmareq(struct tusb_omap_dma_ch *chdat)
381 u32 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
382 int i, dmareq_nr = -1;
384 for (i = 0; i < MAX_DMAREQ; i++) {
385 int cur = (reg & (0xf << (i * 5))) >> (i * 5);
395 reg |= (chdat->epnum << (dmareq_nr * 5));
397 reg |= ((1 << 4) << (dmareq_nr * 5));
398 musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
400 chdat->dma_data = &chdat->tusb_dma->dma_pool[dmareq_nr];
405 static inline void tusb_omap_dma_free_dmareq(struct tusb_omap_dma_ch *chdat)
409 if (!chdat || !chdat->dma_data || chdat->dma_data->dmareq < 0)
412 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP);
413 reg &= ~(0x1f << (chdat->dma_data->dmareq * 5));
414 musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg);
416 chdat->dma_data = NULL;
419 static struct dma_channel *dma_channel_pool[MAX_DMAREQ];
421 static struct dma_channel *
422 tusb_omap_dma_allocate(struct dma_controller *c,
423 struct musb_hw_ep *hw_ep,
427 struct tusb_omap_dma *tusb_dma;
429 struct dma_channel *channel = NULL;
430 struct tusb_omap_dma_ch *chdat = NULL;
431 struct tusb_dma_data *dma_data = NULL;
433 tusb_dma = container_of(c, struct tusb_omap_dma, controller);
434 musb = tusb_dma->controller.musb;
436 /* REVISIT: Why does dmareq5 not work? */
437 if (hw_ep->epnum == 0) {
438 dev_dbg(musb->controller, "Not allowing DMA for ep0 %s\n", tx ? "tx" : "rx");
442 for (i = 0; i < MAX_DMAREQ; i++) {
443 struct dma_channel *ch = dma_channel_pool[i];
444 if (ch->status == MUSB_DMA_STATUS_UNKNOWN) {
445 ch->status = MUSB_DMA_STATUS_FREE;
447 chdat = ch->private_data;
455 chdat->musb = tusb_dma->controller.musb;
456 chdat->tbase = tusb_dma->tbase;
457 chdat->hw_ep = hw_ep;
458 chdat->epnum = hw_ep->epnum;
459 chdat->completed_len = 0;
460 chdat->tusb_dma = tusb_dma;
466 channel->max_len = 0x7fffffff;
467 channel->desired_mode = 0;
468 channel->actual_len = 0;
470 if (!chdat->dma_data) {
471 if (tusb_dma->multichannel) {
472 ret = tusb_omap_dma_allocate_dmareq(chdat);
476 chdat->dma_data = &tusb_dma->dma_pool[0];
480 dma_data = chdat->dma_data;
482 dev_dbg(musb->controller, "ep%i %s dma: %s dmareq%i\n",
484 chdat->tx ? "tx" : "rx",
485 tusb_dma->multichannel ? "shared" : "dedicated",
491 tusb_omap_dma_free_dmareq(chdat);
493 dev_dbg(musb->controller, "ep%i: Could not get a DMA channel\n", chdat->epnum);
494 channel->status = MUSB_DMA_STATUS_UNKNOWN;
499 static void tusb_omap_dma_release(struct dma_channel *channel)
501 struct tusb_omap_dma_ch *chdat = to_chdat(channel);
502 struct musb *musb = chdat->musb;
504 dev_dbg(musb->controller, "Release for ep%i\n", chdat->epnum);
506 channel->status = MUSB_DMA_STATUS_UNKNOWN;
508 dmaengine_terminate_sync(chdat->dma_data->chan);
509 tusb_omap_dma_free_dmareq(chdat);
514 void tusb_dma_controller_destroy(struct dma_controller *c)
516 struct tusb_omap_dma *tusb_dma;
519 tusb_dma = container_of(c, struct tusb_omap_dma, controller);
520 for (i = 0; i < MAX_DMAREQ; i++) {
521 struct dma_channel *ch = dma_channel_pool[i];
523 kfree(ch->private_data);
527 /* Free up the DMA channels */
528 if (tusb_dma && tusb_dma->dma_pool[i].chan)
529 dma_release_channel(tusb_dma->dma_pool[i].chan);
534 EXPORT_SYMBOL_GPL(tusb_dma_controller_destroy);
536 static int tusb_omap_allocate_dma_pool(struct tusb_omap_dma *tusb_dma)
538 struct musb *musb = tusb_dma->controller.musb;
542 for (i = 0; i < MAX_DMAREQ; i++) {
543 struct tusb_dma_data *dma_data = &tusb_dma->dma_pool[i];
546 * Request DMA channels:
547 * - one channel in case of non multichannel mode
548 * - MAX_DMAREQ number of channels in multichannel mode
550 if (i == 0 || tusb_dma->multichannel) {
553 sprintf(ch_name, "dmareq%d", i);
554 dma_data->chan = dma_request_chan(musb->controller,
556 if (IS_ERR(dma_data->chan)) {
557 dev_err(musb->controller,
558 "Failed to request %s\n", ch_name);
559 ret = PTR_ERR(dma_data->chan);
563 dma_data->dmareq = i;
565 dma_data->dmareq = -1;
572 for (; i >= 0; i--) {
573 struct tusb_dma_data *dma_data = &tusb_dma->dma_pool[i];
575 if (dma_data->dmareq >= 0)
576 dma_release_channel(dma_data->chan);
582 struct dma_controller *
583 tusb_dma_controller_create(struct musb *musb, void __iomem *base)
585 void __iomem *tbase = musb->ctrl_base;
586 struct tusb_omap_dma *tusb_dma;
589 /* REVISIT: Get dmareq lines used from board-*.c */
591 musb_writel(musb->ctrl_base, TUSB_DMA_INT_MASK, 0x7fffffff);
592 musb_writel(musb->ctrl_base, TUSB_DMA_EP_MAP, 0);
594 musb_writel(tbase, TUSB_DMA_REQ_CONF,
595 TUSB_DMA_REQ_CONF_BURST_SIZE(2)
596 | TUSB_DMA_REQ_CONF_DMA_REQ_EN(0x3f)
597 | TUSB_DMA_REQ_CONF_DMA_REQ_ASSER(2));
599 tusb_dma = kzalloc(sizeof(struct tusb_omap_dma), GFP_KERNEL);
603 tusb_dma->controller.musb = musb;
604 tusb_dma->tbase = musb->ctrl_base;
606 tusb_dma->controller.channel_alloc = tusb_omap_dma_allocate;
607 tusb_dma->controller.channel_release = tusb_omap_dma_release;
608 tusb_dma->controller.channel_program = tusb_omap_dma_program;
609 tusb_dma->controller.channel_abort = tusb_omap_dma_abort;
611 if (musb->tusb_revision >= TUSB_REV_30)
612 tusb_dma->multichannel = 1;
614 for (i = 0; i < MAX_DMAREQ; i++) {
615 struct dma_channel *ch;
616 struct tusb_omap_dma_ch *chdat;
618 ch = kzalloc(sizeof(struct dma_channel), GFP_KERNEL);
622 dma_channel_pool[i] = ch;
624 chdat = kzalloc(sizeof(struct tusb_omap_dma_ch), GFP_KERNEL);
628 ch->status = MUSB_DMA_STATUS_UNKNOWN;
629 ch->private_data = chdat;
632 if (tusb_omap_allocate_dma_pool(tusb_dma))
635 return &tusb_dma->controller;
638 musb_dma_controller_destroy(&tusb_dma->controller);
642 EXPORT_SYMBOL_GPL(tusb_dma_controller_create);