1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * drivers/usb/musb/ux500_dma.c 4 * 5 * U8500 DMA support code 6 * 7 * Copyright (C) 2009 STMicroelectronics 8 * Copyright (C) 2011 ST-Ericsson SA 9 * Authors: 10 * Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com> 11 * Praveena Nadahally <praveen.nadahally@stericsson.com> 12 * Rajaram Regupathy <ragupathy.rajaram@stericsson.com> 13 */ 14 15 #include <linux/device.h> 16 #include <linux/interrupt.h> 17 #include <linux/platform_device.h> 18 #include <linux/dma-mapping.h> 19 #include <linux/dmaengine.h> 20 #include <linux/pfn.h> 21 #include <linux/sizes.h> 22 #include <linux/platform_data/usb-musb-ux500.h> 23 #include "musb_core.h" 24 25 static const char *iep_chan_names[] = { "iep_1_9", "iep_2_10", "iep_3_11", "iep_4_12", 26 "iep_5_13", "iep_6_14", "iep_7_15", "iep_8" }; 27 static const char *oep_chan_names[] = { "oep_1_9", "oep_2_10", "oep_3_11", "oep_4_12", 28 "oep_5_13", "oep_6_14", "oep_7_15", "oep_8" }; 29 30 struct ux500_dma_channel { 31 struct dma_channel channel; 32 struct ux500_dma_controller *controller; 33 struct musb_hw_ep *hw_ep; 34 struct dma_chan *dma_chan; 35 unsigned int cur_len; 36 dma_cookie_t cookie; 37 u8 ch_num; 38 u8 is_tx; 39 u8 is_allocated; 40 }; 41 42 struct ux500_dma_controller { 43 struct dma_controller controller; 44 struct ux500_dma_channel rx_channel[UX500_MUSB_DMA_NUM_RX_TX_CHANNELS]; 45 struct ux500_dma_channel tx_channel[UX500_MUSB_DMA_NUM_RX_TX_CHANNELS]; 46 void *private_data; 47 dma_addr_t phy_base; 48 }; 49 50 /* Work function invoked from DMA callback to handle rx transfers. */ 51 static void ux500_dma_callback(void *private_data) 52 { 53 struct dma_channel *channel = private_data; 54 struct ux500_dma_channel *ux500_channel = channel->private_data; 55 struct musb_hw_ep *hw_ep = ux500_channel->hw_ep; 56 struct musb *musb = hw_ep->musb; 57 unsigned long flags; 58 59 dev_dbg(musb->controller, "DMA rx transfer done on hw_ep=%d\n", 60 hw_ep->epnum); 61 62 spin_lock_irqsave(&musb->lock, flags); 63 ux500_channel->channel.actual_len = ux500_channel->cur_len; 64 ux500_channel->channel.status = MUSB_DMA_STATUS_FREE; 65 musb_dma_completion(musb, hw_ep->epnum, ux500_channel->is_tx); 66 spin_unlock_irqrestore(&musb->lock, flags); 67 68 } 69 70 static bool ux500_configure_channel(struct dma_channel *channel, 71 u16 packet_sz, u8 mode, 72 dma_addr_t dma_addr, u32 len) 73 { 74 struct ux500_dma_channel *ux500_channel = channel->private_data; 75 struct musb_hw_ep *hw_ep = ux500_channel->hw_ep; 76 struct dma_chan *dma_chan = ux500_channel->dma_chan; 77 struct dma_async_tx_descriptor *dma_desc; 78 enum dma_transfer_direction direction; 79 struct scatterlist sg; 80 struct dma_slave_config slave_conf; 81 enum dma_slave_buswidth addr_width; 82 struct musb *musb = ux500_channel->controller->private_data; 83 dma_addr_t usb_fifo_addr = (musb->io.fifo_offset(hw_ep->epnum) + 84 ux500_channel->controller->phy_base); 85 86 dev_dbg(musb->controller, 87 "packet_sz=%d, mode=%d, dma_addr=0x%llx, len=%d is_tx=%d\n", 88 packet_sz, mode, (unsigned long long) dma_addr, 89 len, ux500_channel->is_tx); 90 91 ux500_channel->cur_len = len; 92 93 sg_init_table(&sg, 1); 94 sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_addr)), len, 95 offset_in_page(dma_addr)); 96 sg_dma_address(&sg) = dma_addr; 97 sg_dma_len(&sg) = len; 98 99 direction = ux500_channel->is_tx ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM; 100 addr_width = (len & 0x3) ? DMA_SLAVE_BUSWIDTH_1_BYTE : 101 DMA_SLAVE_BUSWIDTH_4_BYTES; 102 103 slave_conf.direction = direction; 104 slave_conf.src_addr = usb_fifo_addr; 105 slave_conf.src_addr_width = addr_width; 106 slave_conf.src_maxburst = 16; 107 slave_conf.dst_addr = usb_fifo_addr; 108 slave_conf.dst_addr_width = addr_width; 109 slave_conf.dst_maxburst = 16; 110 slave_conf.device_fc = false; 111 112 dmaengine_slave_config(dma_chan, &slave_conf); 113 114 dma_desc = dmaengine_prep_slave_sg(dma_chan, &sg, 1, direction, 115 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 116 if (!dma_desc) 117 return false; 118 119 dma_desc->callback = ux500_dma_callback; 120 dma_desc->callback_param = channel; 121 ux500_channel->cookie = dma_desc->tx_submit(dma_desc); 122 123 dma_async_issue_pending(dma_chan); 124 125 return true; 126 } 127 128 static struct dma_channel *ux500_dma_channel_allocate(struct dma_controller *c, 129 struct musb_hw_ep *hw_ep, u8 is_tx) 130 { 131 struct ux500_dma_controller *controller = container_of(c, 132 struct ux500_dma_controller, controller); 133 struct ux500_dma_channel *ux500_channel = NULL; 134 struct musb *musb = controller->private_data; 135 u8 ch_num = hw_ep->epnum - 1; 136 137 /* 8 DMA channels (0 - 7). Each DMA channel can only be allocated 138 * to specified hw_ep. For example DMA channel 0 can only be allocated 139 * to hw_ep 1 and 9. 140 */ 141 if (ch_num > 7) 142 ch_num -= 8; 143 144 if (ch_num >= UX500_MUSB_DMA_NUM_RX_TX_CHANNELS) 145 return NULL; 146 147 ux500_channel = is_tx ? &(controller->tx_channel[ch_num]) : 148 &(controller->rx_channel[ch_num]) ; 149 150 /* Check if channel is already used. */ 151 if (ux500_channel->is_allocated) 152 return NULL; 153 154 ux500_channel->hw_ep = hw_ep; 155 ux500_channel->is_allocated = 1; 156 157 dev_dbg(musb->controller, "hw_ep=%d, is_tx=0x%x, channel=%d\n", 158 hw_ep->epnum, is_tx, ch_num); 159 160 return &(ux500_channel->channel); 161 } 162 163 static void ux500_dma_channel_release(struct dma_channel *channel) 164 { 165 struct ux500_dma_channel *ux500_channel = channel->private_data; 166 struct musb *musb = ux500_channel->controller->private_data; 167 168 dev_dbg(musb->controller, "channel=%d\n", ux500_channel->ch_num); 169 170 if (ux500_channel->is_allocated) { 171 ux500_channel->is_allocated = 0; 172 channel->status = MUSB_DMA_STATUS_FREE; 173 channel->actual_len = 0; 174 } 175 } 176 177 static int ux500_dma_is_compatible(struct dma_channel *channel, 178 u16 maxpacket, void *buf, u32 length) 179 { 180 if ((maxpacket & 0x3) || 181 ((unsigned long int) buf & 0x3) || 182 (length < 512) || 183 (length & 0x3)) 184 return false; 185 else 186 return true; 187 } 188 189 static int ux500_dma_channel_program(struct dma_channel *channel, 190 u16 packet_sz, u8 mode, 191 dma_addr_t dma_addr, u32 len) 192 { 193 int ret; 194 195 BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN || 196 channel->status == MUSB_DMA_STATUS_BUSY); 197 198 channel->status = MUSB_DMA_STATUS_BUSY; 199 channel->actual_len = 0; 200 ret = ux500_configure_channel(channel, packet_sz, mode, dma_addr, len); 201 if (!ret) 202 channel->status = MUSB_DMA_STATUS_FREE; 203 204 return ret; 205 } 206 207 static int ux500_dma_channel_abort(struct dma_channel *channel) 208 { 209 struct ux500_dma_channel *ux500_channel = channel->private_data; 210 struct ux500_dma_controller *controller = ux500_channel->controller; 211 struct musb *musb = controller->private_data; 212 void __iomem *epio = musb->endpoints[ux500_channel->hw_ep->epnum].regs; 213 u16 csr; 214 215 dev_dbg(musb->controller, "channel=%d, is_tx=%d\n", 216 ux500_channel->ch_num, ux500_channel->is_tx); 217 218 if (channel->status == MUSB_DMA_STATUS_BUSY) { 219 if (ux500_channel->is_tx) { 220 csr = musb_readw(epio, MUSB_TXCSR); 221 csr &= ~(MUSB_TXCSR_AUTOSET | 222 MUSB_TXCSR_DMAENAB | 223 MUSB_TXCSR_DMAMODE); 224 musb_writew(epio, MUSB_TXCSR, csr); 225 } else { 226 csr = musb_readw(epio, MUSB_RXCSR); 227 csr &= ~(MUSB_RXCSR_AUTOCLEAR | 228 MUSB_RXCSR_DMAENAB | 229 MUSB_RXCSR_DMAMODE); 230 musb_writew(epio, MUSB_RXCSR, csr); 231 } 232 233 dmaengine_terminate_all(ux500_channel->dma_chan); 234 channel->status = MUSB_DMA_STATUS_FREE; 235 } 236 return 0; 237 } 238 239 static void ux500_dma_controller_stop(struct ux500_dma_controller *controller) 240 { 241 struct ux500_dma_channel *ux500_channel; 242 struct dma_channel *channel; 243 u8 ch_num; 244 245 for (ch_num = 0; ch_num < UX500_MUSB_DMA_NUM_RX_TX_CHANNELS; ch_num++) { 246 channel = &controller->rx_channel[ch_num].channel; 247 ux500_channel = channel->private_data; 248 249 ux500_dma_channel_release(channel); 250 251 if (ux500_channel->dma_chan) 252 dma_release_channel(ux500_channel->dma_chan); 253 } 254 255 for (ch_num = 0; ch_num < UX500_MUSB_DMA_NUM_RX_TX_CHANNELS; ch_num++) { 256 channel = &controller->tx_channel[ch_num].channel; 257 ux500_channel = channel->private_data; 258 259 ux500_dma_channel_release(channel); 260 261 if (ux500_channel->dma_chan) 262 dma_release_channel(ux500_channel->dma_chan); 263 } 264 } 265 266 static int ux500_dma_controller_start(struct ux500_dma_controller *controller) 267 { 268 struct ux500_dma_channel *ux500_channel = NULL; 269 struct musb *musb = controller->private_data; 270 struct device *dev = musb->controller; 271 struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); 272 struct ux500_musb_board_data *data; 273 struct dma_channel *dma_channel = NULL; 274 char **chan_names; 275 u32 ch_num; 276 u8 dir; 277 u8 is_tx = 0; 278 279 void **param_array; 280 struct ux500_dma_channel *channel_array; 281 dma_cap_mask_t mask; 282 283 if (!plat) { 284 dev_err(musb->controller, "No platform data\n"); 285 return -EINVAL; 286 } 287 288 data = plat->board_data; 289 290 dma_cap_zero(mask); 291 dma_cap_set(DMA_SLAVE, mask); 292 293 /* Prepare the loop for RX channels */ 294 channel_array = controller->rx_channel; 295 param_array = data ? data->dma_rx_param_array : NULL; 296 chan_names = (char **)iep_chan_names; 297 298 for (dir = 0; dir < 2; dir++) { 299 for (ch_num = 0; 300 ch_num < UX500_MUSB_DMA_NUM_RX_TX_CHANNELS; 301 ch_num++) { 302 ux500_channel = &channel_array[ch_num]; 303 ux500_channel->controller = controller; 304 ux500_channel->ch_num = ch_num; 305 ux500_channel->is_tx = is_tx; 306 307 dma_channel = &(ux500_channel->channel); 308 dma_channel->private_data = ux500_channel; 309 dma_channel->status = MUSB_DMA_STATUS_FREE; 310 dma_channel->max_len = SZ_16M; 311 312 ux500_channel->dma_chan = 313 dma_request_chan(dev, chan_names[ch_num]); 314 315 if (IS_ERR(ux500_channel->dma_chan)) 316 ux500_channel->dma_chan = 317 dma_request_channel(mask, 318 data ? 319 data->dma_filter : 320 NULL, 321 param_array ? 322 param_array[ch_num] : 323 NULL); 324 325 if (!ux500_channel->dma_chan) { 326 ERR("Dma pipe allocation error dir=%d ch=%d\n", 327 dir, ch_num); 328 329 /* Release already allocated channels */ 330 ux500_dma_controller_stop(controller); 331 332 return -EBUSY; 333 } 334 335 } 336 337 /* Prepare the loop for TX channels */ 338 channel_array = controller->tx_channel; 339 param_array = data ? data->dma_tx_param_array : NULL; 340 chan_names = (char **)oep_chan_names; 341 is_tx = 1; 342 } 343 344 return 0; 345 } 346 347 void ux500_dma_controller_destroy(struct dma_controller *c) 348 { 349 struct ux500_dma_controller *controller = container_of(c, 350 struct ux500_dma_controller, controller); 351 352 ux500_dma_controller_stop(controller); 353 kfree(controller); 354 } 355 EXPORT_SYMBOL_GPL(ux500_dma_controller_destroy); 356 357 struct dma_controller * 358 ux500_dma_controller_create(struct musb *musb, void __iomem *base) 359 { 360 struct ux500_dma_controller *controller; 361 struct platform_device *pdev = to_platform_device(musb->controller); 362 struct resource *iomem; 363 int ret; 364 365 controller = kzalloc(sizeof(*controller), GFP_KERNEL); 366 if (!controller) 367 goto kzalloc_fail; 368 369 controller->private_data = musb; 370 371 /* Save physical address for DMA controller. */ 372 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 373 if (!iomem) { 374 dev_err(musb->controller, "no memory resource defined\n"); 375 goto plat_get_fail; 376 } 377 378 controller->phy_base = (dma_addr_t) iomem->start; 379 380 controller->controller.channel_alloc = ux500_dma_channel_allocate; 381 controller->controller.channel_release = ux500_dma_channel_release; 382 controller->controller.channel_program = ux500_dma_channel_program; 383 controller->controller.channel_abort = ux500_dma_channel_abort; 384 controller->controller.is_compatible = ux500_dma_is_compatible; 385 386 ret = ux500_dma_controller_start(controller); 387 if (ret) 388 goto plat_get_fail; 389 return &controller->controller; 390 391 plat_get_fail: 392 kfree(controller); 393 kzalloc_fail: 394 return NULL; 395 } 396 EXPORT_SYMBOL_GPL(ux500_dma_controller_create); 397