1 /* 2 * Copyright (C) 2013-2014 Renesas Electronics Europe Ltd. 3 * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of version 2 of the GNU General Public License as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/bitmap.h> 11 #include <linux/bitops.h> 12 #include <linux/clk.h> 13 #include <linux/dma-mapping.h> 14 #include <linux/dmaengine.h> 15 #include <linux/err.h> 16 #include <linux/interrupt.h> 17 #include <linux/io.h> 18 #include <linux/log2.h> 19 #include <linux/module.h> 20 #include <linux/of.h> 21 #include <linux/of_device.h> 22 #include <linux/of_dma.h> 23 #include <linux/platform_device.h> 24 #include <linux/slab.h> 25 26 #include <dt-bindings/dma/nbpfaxi.h> 27 28 #include "dmaengine.h" 29 30 #define NBPF_REG_CHAN_OFFSET 0 31 #define NBPF_REG_CHAN_SIZE 0x40 32 33 /* Channel Current Transaction Byte register */ 34 #define NBPF_CHAN_CUR_TR_BYTE 0x20 35 36 /* Channel Status register */ 37 #define NBPF_CHAN_STAT 0x24 38 #define NBPF_CHAN_STAT_EN 1 39 #define NBPF_CHAN_STAT_TACT 4 40 #define NBPF_CHAN_STAT_ERR 0x10 41 #define NBPF_CHAN_STAT_END 0x20 42 #define NBPF_CHAN_STAT_TC 0x40 43 #define NBPF_CHAN_STAT_DER 0x400 44 45 /* Channel Control register */ 46 #define NBPF_CHAN_CTRL 0x28 47 #define NBPF_CHAN_CTRL_SETEN 1 48 #define NBPF_CHAN_CTRL_CLREN 2 49 #define NBPF_CHAN_CTRL_STG 4 50 #define NBPF_CHAN_CTRL_SWRST 8 51 #define NBPF_CHAN_CTRL_CLRRQ 0x10 52 #define NBPF_CHAN_CTRL_CLREND 0x20 53 #define NBPF_CHAN_CTRL_CLRTC 0x40 54 #define NBPF_CHAN_CTRL_SETSUS 0x100 55 #define NBPF_CHAN_CTRL_CLRSUS 0x200 56 57 /* Channel Configuration register */ 58 #define NBPF_CHAN_CFG 0x2c 59 #define NBPF_CHAN_CFG_SEL 7 /* terminal SELect: 0..7 */ 60 #define NBPF_CHAN_CFG_REQD 8 /* REQuest Direction: DMAREQ is 0: input, 1: output */ 61 #define NBPF_CHAN_CFG_LOEN 0x10 /* LOw ENable: low DMA request line is: 0: inactive, 1: active */ 62 #define NBPF_CHAN_CFG_HIEN 0x20 /* HIgh ENable: high DMA request line is: 0: inactive, 1: active */ 63 #define NBPF_CHAN_CFG_LVL 0x40 /* LeVeL: DMA request line is sensed as 0: edge, 1: level */ 64 #define NBPF_CHAN_CFG_AM 0x700 /* ACK Mode: 0: Pulse mode, 1: Level mode, b'1x: Bus Cycle */ 65 #define NBPF_CHAN_CFG_SDS 0xf000 /* Source Data Size: 0: 8 bits,... , 7: 1024 bits */ 66 #define NBPF_CHAN_CFG_DDS 0xf0000 /* Destination Data Size: as above */ 67 #define NBPF_CHAN_CFG_SAD 0x100000 /* Source ADdress counting: 0: increment, 1: fixed */ 68 #define NBPF_CHAN_CFG_DAD 0x200000 /* Destination ADdress counting: 0: increment, 1: fixed */ 69 #define NBPF_CHAN_CFG_TM 0x400000 /* Transfer Mode: 0: single, 1: block TM */ 70 #define NBPF_CHAN_CFG_DEM 0x1000000 /* DMAEND interrupt Mask */ 71 #define NBPF_CHAN_CFG_TCM 0x2000000 /* DMATCO interrupt Mask */ 72 #define NBPF_CHAN_CFG_SBE 0x8000000 /* Sweep Buffer Enable */ 73 #define NBPF_CHAN_CFG_RSEL 0x10000000 /* RM: Register Set sELect */ 74 #define NBPF_CHAN_CFG_RSW 0x20000000 /* RM: Register Select sWitch */ 75 #define NBPF_CHAN_CFG_REN 0x40000000 /* RM: Register Set Enable */ 76 #define NBPF_CHAN_CFG_DMS 0x80000000 /* 0: register mode (RM), 1: link mode (LM) */ 77 78 #define NBPF_CHAN_NXLA 0x38 79 #define NBPF_CHAN_CRLA 0x3c 80 81 /* Link Header field */ 82 #define NBPF_HEADER_LV 1 83 #define NBPF_HEADER_LE 2 84 #define NBPF_HEADER_WBD 4 85 #define NBPF_HEADER_DIM 8 86 87 #define NBPF_CTRL 0x300 88 #define NBPF_CTRL_PR 1 /* 0: fixed priority, 1: round robin */ 89 #define NBPF_CTRL_LVINT 2 /* DMAEND and DMAERR signalling: 0: pulse, 1: level */ 90 91 #define NBPF_DSTAT_ER 0x314 92 #define NBPF_DSTAT_END 0x318 93 94 #define NBPF_DMA_BUSWIDTHS \ 95 (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \ 96 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ 97 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ 98 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \ 99 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)) 100 101 struct nbpf_config { 102 int num_channels; 103 int buffer_size; 104 }; 105 106 /* 107 * We've got 3 types of objects, used to describe DMA transfers: 108 * 1. high-level descriptor, containing a struct dma_async_tx_descriptor object 109 * in it, used to communicate with the user 110 * 2. hardware DMA link descriptors, that we pass to DMAC for DMA transfer 111 * queuing, these must be DMAable, using either the streaming DMA API or 112 * allocated from coherent memory - one per SG segment 113 * 3. one per SG segment descriptors, used to manage HW link descriptors from 114 * (2). They do not have to be DMAable. They can either be (a) allocated 115 * together with link descriptors as mixed (DMA / CPU) objects, or (b) 116 * separately. Even if allocated separately it would be best to link them 117 * to link descriptors once during channel resource allocation and always 118 * use them as a single object. 119 * Therefore for both cases (a) and (b) at run-time objects (2) and (3) shall be 120 * treated as a single SG segment descriptor. 121 */ 122 123 struct nbpf_link_reg { 124 u32 header; 125 u32 src_addr; 126 u32 dst_addr; 127 u32 transaction_size; 128 u32 config; 129 u32 interval; 130 u32 extension; 131 u32 next; 132 } __packed; 133 134 struct nbpf_device; 135 struct nbpf_channel; 136 struct nbpf_desc; 137 138 struct nbpf_link_desc { 139 struct nbpf_link_reg *hwdesc; 140 dma_addr_t hwdesc_dma_addr; 141 struct nbpf_desc *desc; 142 struct list_head node; 143 }; 144 145 /** 146 * struct nbpf_desc - DMA transfer descriptor 147 * @async_tx: dmaengine object 148 * @user_wait: waiting for a user ack 149 * @length: total transfer length 150 * @sg: list of hardware descriptors, represented by struct nbpf_link_desc 151 * @node: member in channel descriptor lists 152 */ 153 struct nbpf_desc { 154 struct dma_async_tx_descriptor async_tx; 155 bool user_wait; 156 size_t length; 157 struct nbpf_channel *chan; 158 struct list_head sg; 159 struct list_head node; 160 }; 161 162 /* Take a wild guess: allocate 4 segments per descriptor */ 163 #define NBPF_SEGMENTS_PER_DESC 4 164 #define NBPF_DESCS_PER_PAGE ((PAGE_SIZE - sizeof(struct list_head)) / \ 165 (sizeof(struct nbpf_desc) + \ 166 NBPF_SEGMENTS_PER_DESC * \ 167 (sizeof(struct nbpf_link_desc) + sizeof(struct nbpf_link_reg)))) 168 #define NBPF_SEGMENTS_PER_PAGE (NBPF_SEGMENTS_PER_DESC * NBPF_DESCS_PER_PAGE) 169 170 struct nbpf_desc_page { 171 struct list_head node; 172 struct nbpf_desc desc[NBPF_DESCS_PER_PAGE]; 173 struct nbpf_link_desc ldesc[NBPF_SEGMENTS_PER_PAGE]; 174 struct nbpf_link_reg hwdesc[NBPF_SEGMENTS_PER_PAGE]; 175 }; 176 177 /** 178 * struct nbpf_channel - one DMAC channel 179 * @dma_chan: standard dmaengine channel object 180 * @base: register address base 181 * @nbpf: DMAC 182 * @name: IRQ name 183 * @irq: IRQ number 184 * @slave_addr: address for slave DMA 185 * @slave_width:slave data size in bytes 186 * @slave_burst:maximum slave burst size in bytes 187 * @terminal: DMA terminal, assigned to this channel 188 * @dmarq_cfg: DMA request line configuration - high / low, edge / level for NBPF_CHAN_CFG 189 * @flags: configuration flags from DT 190 * @lock: protect descriptor lists 191 * @free_links: list of free link descriptors 192 * @free: list of free descriptors 193 * @queued: list of queued descriptors 194 * @active: list of descriptors, scheduled for processing 195 * @done: list of completed descriptors, waiting post-processing 196 * @desc_page: list of additionally allocated descriptor pages - if any 197 */ 198 struct nbpf_channel { 199 struct dma_chan dma_chan; 200 struct tasklet_struct tasklet; 201 void __iomem *base; 202 struct nbpf_device *nbpf; 203 char name[16]; 204 int irq; 205 dma_addr_t slave_src_addr; 206 size_t slave_src_width; 207 size_t slave_src_burst; 208 dma_addr_t slave_dst_addr; 209 size_t slave_dst_width; 210 size_t slave_dst_burst; 211 unsigned int terminal; 212 u32 dmarq_cfg; 213 unsigned long flags; 214 spinlock_t lock; 215 struct list_head free_links; 216 struct list_head free; 217 struct list_head queued; 218 struct list_head active; 219 struct list_head done; 220 struct list_head desc_page; 221 struct nbpf_desc *running; 222 bool paused; 223 }; 224 225 struct nbpf_device { 226 struct dma_device dma_dev; 227 void __iomem *base; 228 u32 max_burst_mem_read; 229 u32 max_burst_mem_write; 230 struct clk *clk; 231 const struct nbpf_config *config; 232 unsigned int eirq; 233 struct nbpf_channel chan[]; 234 }; 235 236 enum nbpf_model { 237 NBPF1B4, 238 NBPF1B8, 239 NBPF1B16, 240 NBPF4B4, 241 NBPF4B8, 242 NBPF4B16, 243 NBPF8B4, 244 NBPF8B8, 245 NBPF8B16, 246 }; 247 248 static struct nbpf_config nbpf_cfg[] = { 249 [NBPF1B4] = { 250 .num_channels = 1, 251 .buffer_size = 4, 252 }, 253 [NBPF1B8] = { 254 .num_channels = 1, 255 .buffer_size = 8, 256 }, 257 [NBPF1B16] = { 258 .num_channels = 1, 259 .buffer_size = 16, 260 }, 261 [NBPF4B4] = { 262 .num_channels = 4, 263 .buffer_size = 4, 264 }, 265 [NBPF4B8] = { 266 .num_channels = 4, 267 .buffer_size = 8, 268 }, 269 [NBPF4B16] = { 270 .num_channels = 4, 271 .buffer_size = 16, 272 }, 273 [NBPF8B4] = { 274 .num_channels = 8, 275 .buffer_size = 4, 276 }, 277 [NBPF8B8] = { 278 .num_channels = 8, 279 .buffer_size = 8, 280 }, 281 [NBPF8B16] = { 282 .num_channels = 8, 283 .buffer_size = 16, 284 }, 285 }; 286 287 #define nbpf_to_chan(d) container_of(d, struct nbpf_channel, dma_chan) 288 289 /* 290 * dmaengine drivers seem to have a lot in common and instead of sharing more 291 * code, they reimplement those common algorithms independently. In this driver 292 * we try to separate the hardware-specific part from the (largely) generic 293 * part. This improves code readability and makes it possible in the future to 294 * reuse the generic code in form of a helper library. That generic code should 295 * be suitable for various DMA controllers, using transfer descriptors in RAM 296 * and pushing one SG list at a time to the DMA controller. 297 */ 298 299 /* Hardware-specific part */ 300 301 static inline u32 nbpf_chan_read(struct nbpf_channel *chan, 302 unsigned int offset) 303 { 304 u32 data = ioread32(chan->base + offset); 305 dev_dbg(chan->dma_chan.device->dev, "%s(0x%p + 0x%x) = 0x%x\n", 306 __func__, chan->base, offset, data); 307 return data; 308 } 309 310 static inline void nbpf_chan_write(struct nbpf_channel *chan, 311 unsigned int offset, u32 data) 312 { 313 iowrite32(data, chan->base + offset); 314 dev_dbg(chan->dma_chan.device->dev, "%s(0x%p + 0x%x) = 0x%x\n", 315 __func__, chan->base, offset, data); 316 } 317 318 static inline u32 nbpf_read(struct nbpf_device *nbpf, 319 unsigned int offset) 320 { 321 u32 data = ioread32(nbpf->base + offset); 322 dev_dbg(nbpf->dma_dev.dev, "%s(0x%p + 0x%x) = 0x%x\n", 323 __func__, nbpf->base, offset, data); 324 return data; 325 } 326 327 static inline void nbpf_write(struct nbpf_device *nbpf, 328 unsigned int offset, u32 data) 329 { 330 iowrite32(data, nbpf->base + offset); 331 dev_dbg(nbpf->dma_dev.dev, "%s(0x%p + 0x%x) = 0x%x\n", 332 __func__, nbpf->base, offset, data); 333 } 334 335 static void nbpf_chan_halt(struct nbpf_channel *chan) 336 { 337 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_CLREN); 338 } 339 340 static bool nbpf_status_get(struct nbpf_channel *chan) 341 { 342 u32 status = nbpf_read(chan->nbpf, NBPF_DSTAT_END); 343 344 return status & BIT(chan - chan->nbpf->chan); 345 } 346 347 static void nbpf_status_ack(struct nbpf_channel *chan) 348 { 349 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_CLREND); 350 } 351 352 static u32 nbpf_error_get(struct nbpf_device *nbpf) 353 { 354 return nbpf_read(nbpf, NBPF_DSTAT_ER); 355 } 356 357 static struct nbpf_channel *nbpf_error_get_channel(struct nbpf_device *nbpf, u32 error) 358 { 359 return nbpf->chan + __ffs(error); 360 } 361 362 static void nbpf_error_clear(struct nbpf_channel *chan) 363 { 364 u32 status; 365 int i; 366 367 /* Stop the channel, make sure DMA has been aborted */ 368 nbpf_chan_halt(chan); 369 370 for (i = 1000; i; i--) { 371 status = nbpf_chan_read(chan, NBPF_CHAN_STAT); 372 if (!(status & NBPF_CHAN_STAT_TACT)) 373 break; 374 cpu_relax(); 375 } 376 377 if (!i) 378 dev_err(chan->dma_chan.device->dev, 379 "%s(): abort timeout, channel status 0x%x\n", __func__, status); 380 381 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_SWRST); 382 } 383 384 static int nbpf_start(struct nbpf_desc *desc) 385 { 386 struct nbpf_channel *chan = desc->chan; 387 struct nbpf_link_desc *ldesc = list_first_entry(&desc->sg, struct nbpf_link_desc, node); 388 389 nbpf_chan_write(chan, NBPF_CHAN_NXLA, (u32)ldesc->hwdesc_dma_addr); 390 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_SETEN | NBPF_CHAN_CTRL_CLRSUS); 391 chan->paused = false; 392 393 /* Software trigger MEMCPY - only MEMCPY uses the block mode */ 394 if (ldesc->hwdesc->config & NBPF_CHAN_CFG_TM) 395 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_STG); 396 397 dev_dbg(chan->nbpf->dma_dev.dev, "%s(): next 0x%x, cur 0x%x\n", __func__, 398 nbpf_chan_read(chan, NBPF_CHAN_NXLA), nbpf_chan_read(chan, NBPF_CHAN_CRLA)); 399 400 return 0; 401 } 402 403 static void nbpf_chan_prepare(struct nbpf_channel *chan) 404 { 405 chan->dmarq_cfg = (chan->flags & NBPF_SLAVE_RQ_HIGH ? NBPF_CHAN_CFG_HIEN : 0) | 406 (chan->flags & NBPF_SLAVE_RQ_LOW ? NBPF_CHAN_CFG_LOEN : 0) | 407 (chan->flags & NBPF_SLAVE_RQ_LEVEL ? 408 NBPF_CHAN_CFG_LVL | (NBPF_CHAN_CFG_AM & 0x200) : 0) | 409 chan->terminal; 410 } 411 412 static void nbpf_chan_prepare_default(struct nbpf_channel *chan) 413 { 414 /* Don't output DMAACK */ 415 chan->dmarq_cfg = NBPF_CHAN_CFG_AM & 0x400; 416 chan->terminal = 0; 417 chan->flags = 0; 418 } 419 420 static void nbpf_chan_configure(struct nbpf_channel *chan) 421 { 422 /* 423 * We assume, that only the link mode and DMA request line configuration 424 * have to be set in the configuration register manually. Dynamic 425 * per-transfer configuration will be loaded from transfer descriptors. 426 */ 427 nbpf_chan_write(chan, NBPF_CHAN_CFG, NBPF_CHAN_CFG_DMS | chan->dmarq_cfg); 428 } 429 430 static u32 nbpf_xfer_ds(struct nbpf_device *nbpf, size_t size, 431 enum dma_transfer_direction direction) 432 { 433 int max_burst = nbpf->config->buffer_size * 8; 434 435 if (nbpf->max_burst_mem_read || nbpf->max_burst_mem_write) { 436 switch (direction) { 437 case DMA_MEM_TO_MEM: 438 max_burst = min_not_zero(nbpf->max_burst_mem_read, 439 nbpf->max_burst_mem_write); 440 break; 441 case DMA_MEM_TO_DEV: 442 if (nbpf->max_burst_mem_read) 443 max_burst = nbpf->max_burst_mem_read; 444 break; 445 case DMA_DEV_TO_MEM: 446 if (nbpf->max_burst_mem_write) 447 max_burst = nbpf->max_burst_mem_write; 448 break; 449 case DMA_DEV_TO_DEV: 450 default: 451 break; 452 } 453 } 454 455 /* Maximum supported bursts depend on the buffer size */ 456 return min_t(int, __ffs(size), ilog2(max_burst)); 457 } 458 459 static size_t nbpf_xfer_size(struct nbpf_device *nbpf, 460 enum dma_slave_buswidth width, u32 burst) 461 { 462 size_t size; 463 464 if (!burst) 465 burst = 1; 466 467 switch (width) { 468 case DMA_SLAVE_BUSWIDTH_8_BYTES: 469 size = 8 * burst; 470 break; 471 472 case DMA_SLAVE_BUSWIDTH_4_BYTES: 473 size = 4 * burst; 474 break; 475 476 case DMA_SLAVE_BUSWIDTH_2_BYTES: 477 size = 2 * burst; 478 break; 479 480 default: 481 pr_warn("%s(): invalid bus width %u\n", __func__, width); 482 case DMA_SLAVE_BUSWIDTH_1_BYTE: 483 size = burst; 484 } 485 486 return nbpf_xfer_ds(nbpf, size, DMA_TRANS_NONE); 487 } 488 489 /* 490 * We need a way to recognise slaves, whose data is sent "raw" over the bus, 491 * i.e. it isn't known in advance how many bytes will be received. Therefore 492 * the slave driver has to provide a "large enough" buffer and either read the 493 * buffer, when it is full, or detect, that some data has arrived, then wait for 494 * a timeout, if no more data arrives - receive what's already there. We want to 495 * handle such slaves in a special way to allow an optimised mode for other 496 * users, for whom the amount of data is known in advance. So far there's no way 497 * to recognise such slaves. We use a data-width check to distinguish between 498 * the SD host and the PL011 UART. 499 */ 500 501 static int nbpf_prep_one(struct nbpf_link_desc *ldesc, 502 enum dma_transfer_direction direction, 503 dma_addr_t src, dma_addr_t dst, size_t size, bool last) 504 { 505 struct nbpf_link_reg *hwdesc = ldesc->hwdesc; 506 struct nbpf_desc *desc = ldesc->desc; 507 struct nbpf_channel *chan = desc->chan; 508 struct device *dev = chan->dma_chan.device->dev; 509 size_t mem_xfer, slave_xfer; 510 bool can_burst; 511 512 hwdesc->header = NBPF_HEADER_WBD | NBPF_HEADER_LV | 513 (last ? NBPF_HEADER_LE : 0); 514 515 hwdesc->src_addr = src; 516 hwdesc->dst_addr = dst; 517 hwdesc->transaction_size = size; 518 519 /* 520 * set config: SAD, DAD, DDS, SDS, etc. 521 * Note on transfer sizes: the DMAC can perform unaligned DMA transfers, 522 * but it is important to have transaction size a multiple of both 523 * receiver and transmitter transfer sizes. It is also possible to use 524 * different RAM and device transfer sizes, and it does work well with 525 * some devices, e.g. with V08R07S01E SD host controllers, which can use 526 * 128 byte transfers. But this doesn't work with other devices, 527 * especially when the transaction size is unknown. This is the case, 528 * e.g. with serial drivers like amba-pl011.c. For reception it sets up 529 * the transaction size of 4K and if fewer bytes are received, it 530 * pauses DMA and reads out data received via DMA as well as those left 531 * in the Rx FIFO. For this to work with the RAM side using burst 532 * transfers we enable the SBE bit and terminate the transfer in our 533 * .device_pause handler. 534 */ 535 mem_xfer = nbpf_xfer_ds(chan->nbpf, size, direction); 536 537 switch (direction) { 538 case DMA_DEV_TO_MEM: 539 can_burst = chan->slave_src_width >= 3; 540 slave_xfer = min(mem_xfer, can_burst ? 541 chan->slave_src_burst : chan->slave_src_width); 542 /* 543 * Is the slave narrower than 64 bits, i.e. isn't using the full 544 * bus width and cannot use bursts? 545 */ 546 if (mem_xfer > chan->slave_src_burst && !can_burst) 547 mem_xfer = chan->slave_src_burst; 548 /* Device-to-RAM DMA is unreliable without REQD set */ 549 hwdesc->config = NBPF_CHAN_CFG_SAD | (NBPF_CHAN_CFG_DDS & (mem_xfer << 16)) | 550 (NBPF_CHAN_CFG_SDS & (slave_xfer << 12)) | NBPF_CHAN_CFG_REQD | 551 NBPF_CHAN_CFG_SBE; 552 break; 553 554 case DMA_MEM_TO_DEV: 555 slave_xfer = min(mem_xfer, chan->slave_dst_width >= 3 ? 556 chan->slave_dst_burst : chan->slave_dst_width); 557 hwdesc->config = NBPF_CHAN_CFG_DAD | (NBPF_CHAN_CFG_SDS & (mem_xfer << 12)) | 558 (NBPF_CHAN_CFG_DDS & (slave_xfer << 16)) | NBPF_CHAN_CFG_REQD; 559 break; 560 561 case DMA_MEM_TO_MEM: 562 hwdesc->config = NBPF_CHAN_CFG_TCM | NBPF_CHAN_CFG_TM | 563 (NBPF_CHAN_CFG_SDS & (mem_xfer << 12)) | 564 (NBPF_CHAN_CFG_DDS & (mem_xfer << 16)); 565 break; 566 567 default: 568 return -EINVAL; 569 } 570 571 hwdesc->config |= chan->dmarq_cfg | (last ? 0 : NBPF_CHAN_CFG_DEM) | 572 NBPF_CHAN_CFG_DMS; 573 574 dev_dbg(dev, "%s(): desc @ %pad: hdr 0x%x, cfg 0x%x, %zu @ %pad -> %pad\n", 575 __func__, &ldesc->hwdesc_dma_addr, hwdesc->header, 576 hwdesc->config, size, &src, &dst); 577 578 dma_sync_single_for_device(dev, ldesc->hwdesc_dma_addr, sizeof(*hwdesc), 579 DMA_TO_DEVICE); 580 581 return 0; 582 } 583 584 static size_t nbpf_bytes_left(struct nbpf_channel *chan) 585 { 586 return nbpf_chan_read(chan, NBPF_CHAN_CUR_TR_BYTE); 587 } 588 589 static void nbpf_configure(struct nbpf_device *nbpf) 590 { 591 nbpf_write(nbpf, NBPF_CTRL, NBPF_CTRL_LVINT); 592 } 593 594 /* Generic part */ 595 596 /* DMA ENGINE functions */ 597 static void nbpf_issue_pending(struct dma_chan *dchan) 598 { 599 struct nbpf_channel *chan = nbpf_to_chan(dchan); 600 unsigned long flags; 601 602 dev_dbg(dchan->device->dev, "Entry %s()\n", __func__); 603 604 spin_lock_irqsave(&chan->lock, flags); 605 if (list_empty(&chan->queued)) 606 goto unlock; 607 608 list_splice_tail_init(&chan->queued, &chan->active); 609 610 if (!chan->running) { 611 struct nbpf_desc *desc = list_first_entry(&chan->active, 612 struct nbpf_desc, node); 613 if (!nbpf_start(desc)) 614 chan->running = desc; 615 } 616 617 unlock: 618 spin_unlock_irqrestore(&chan->lock, flags); 619 } 620 621 static enum dma_status nbpf_tx_status(struct dma_chan *dchan, 622 dma_cookie_t cookie, struct dma_tx_state *state) 623 { 624 struct nbpf_channel *chan = nbpf_to_chan(dchan); 625 enum dma_status status = dma_cookie_status(dchan, cookie, state); 626 627 if (state) { 628 dma_cookie_t running; 629 unsigned long flags; 630 631 spin_lock_irqsave(&chan->lock, flags); 632 running = chan->running ? chan->running->async_tx.cookie : -EINVAL; 633 634 if (cookie == running) { 635 state->residue = nbpf_bytes_left(chan); 636 dev_dbg(dchan->device->dev, "%s(): residue %u\n", __func__, 637 state->residue); 638 } else if (status == DMA_IN_PROGRESS) { 639 struct nbpf_desc *desc; 640 bool found = false; 641 642 list_for_each_entry(desc, &chan->active, node) 643 if (desc->async_tx.cookie == cookie) { 644 found = true; 645 break; 646 } 647 648 if (!found) 649 list_for_each_entry(desc, &chan->queued, node) 650 if (desc->async_tx.cookie == cookie) { 651 found = true; 652 break; 653 654 } 655 656 state->residue = found ? desc->length : 0; 657 } 658 659 spin_unlock_irqrestore(&chan->lock, flags); 660 } 661 662 if (chan->paused) 663 status = DMA_PAUSED; 664 665 return status; 666 } 667 668 static dma_cookie_t nbpf_tx_submit(struct dma_async_tx_descriptor *tx) 669 { 670 struct nbpf_desc *desc = container_of(tx, struct nbpf_desc, async_tx); 671 struct nbpf_channel *chan = desc->chan; 672 unsigned long flags; 673 dma_cookie_t cookie; 674 675 spin_lock_irqsave(&chan->lock, flags); 676 cookie = dma_cookie_assign(tx); 677 list_add_tail(&desc->node, &chan->queued); 678 spin_unlock_irqrestore(&chan->lock, flags); 679 680 dev_dbg(chan->dma_chan.device->dev, "Entry %s(%d)\n", __func__, cookie); 681 682 return cookie; 683 } 684 685 static int nbpf_desc_page_alloc(struct nbpf_channel *chan) 686 { 687 struct dma_chan *dchan = &chan->dma_chan; 688 struct nbpf_desc_page *dpage = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA); 689 struct nbpf_link_desc *ldesc; 690 struct nbpf_link_reg *hwdesc; 691 struct nbpf_desc *desc; 692 LIST_HEAD(head); 693 LIST_HEAD(lhead); 694 int i; 695 struct device *dev = dchan->device->dev; 696 697 if (!dpage) 698 return -ENOMEM; 699 700 dev_dbg(dev, "%s(): alloc %lu descriptors, %lu segments, total alloc %zu\n", 701 __func__, NBPF_DESCS_PER_PAGE, NBPF_SEGMENTS_PER_PAGE, sizeof(*dpage)); 702 703 for (i = 0, ldesc = dpage->ldesc, hwdesc = dpage->hwdesc; 704 i < ARRAY_SIZE(dpage->ldesc); 705 i++, ldesc++, hwdesc++) { 706 ldesc->hwdesc = hwdesc; 707 list_add_tail(&ldesc->node, &lhead); 708 ldesc->hwdesc_dma_addr = dma_map_single(dchan->device->dev, 709 hwdesc, sizeof(*hwdesc), DMA_TO_DEVICE); 710 711 dev_dbg(dev, "%s(): mapped 0x%p to %pad\n", __func__, 712 hwdesc, &ldesc->hwdesc_dma_addr); 713 } 714 715 for (i = 0, desc = dpage->desc; 716 i < ARRAY_SIZE(dpage->desc); 717 i++, desc++) { 718 dma_async_tx_descriptor_init(&desc->async_tx, dchan); 719 desc->async_tx.tx_submit = nbpf_tx_submit; 720 desc->chan = chan; 721 INIT_LIST_HEAD(&desc->sg); 722 list_add_tail(&desc->node, &head); 723 } 724 725 /* 726 * This function cannot be called from interrupt context, so, no need to 727 * save flags 728 */ 729 spin_lock_irq(&chan->lock); 730 list_splice_tail(&lhead, &chan->free_links); 731 list_splice_tail(&head, &chan->free); 732 list_add(&dpage->node, &chan->desc_page); 733 spin_unlock_irq(&chan->lock); 734 735 return ARRAY_SIZE(dpage->desc); 736 } 737 738 static void nbpf_desc_put(struct nbpf_desc *desc) 739 { 740 struct nbpf_channel *chan = desc->chan; 741 struct nbpf_link_desc *ldesc, *tmp; 742 unsigned long flags; 743 744 spin_lock_irqsave(&chan->lock, flags); 745 list_for_each_entry_safe(ldesc, tmp, &desc->sg, node) 746 list_move(&ldesc->node, &chan->free_links); 747 748 list_add(&desc->node, &chan->free); 749 spin_unlock_irqrestore(&chan->lock, flags); 750 } 751 752 static void nbpf_scan_acked(struct nbpf_channel *chan) 753 { 754 struct nbpf_desc *desc, *tmp; 755 unsigned long flags; 756 LIST_HEAD(head); 757 758 spin_lock_irqsave(&chan->lock, flags); 759 list_for_each_entry_safe(desc, tmp, &chan->done, node) 760 if (async_tx_test_ack(&desc->async_tx) && desc->user_wait) { 761 list_move(&desc->node, &head); 762 desc->user_wait = false; 763 } 764 spin_unlock_irqrestore(&chan->lock, flags); 765 766 list_for_each_entry_safe(desc, tmp, &head, node) { 767 list_del(&desc->node); 768 nbpf_desc_put(desc); 769 } 770 } 771 772 /* 773 * We have to allocate descriptors with the channel lock dropped. This means, 774 * before we re-acquire the lock buffers can be taken already, so we have to 775 * re-check after re-acquiring the lock and possibly retry, if buffers are gone 776 * again. 777 */ 778 static struct nbpf_desc *nbpf_desc_get(struct nbpf_channel *chan, size_t len) 779 { 780 struct nbpf_desc *desc = NULL; 781 struct nbpf_link_desc *ldesc, *prev = NULL; 782 783 nbpf_scan_acked(chan); 784 785 spin_lock_irq(&chan->lock); 786 787 do { 788 int i = 0, ret; 789 790 if (list_empty(&chan->free)) { 791 /* No more free descriptors */ 792 spin_unlock_irq(&chan->lock); 793 ret = nbpf_desc_page_alloc(chan); 794 if (ret < 0) 795 return NULL; 796 spin_lock_irq(&chan->lock); 797 continue; 798 } 799 desc = list_first_entry(&chan->free, struct nbpf_desc, node); 800 list_del(&desc->node); 801 802 do { 803 if (list_empty(&chan->free_links)) { 804 /* No more free link descriptors */ 805 spin_unlock_irq(&chan->lock); 806 ret = nbpf_desc_page_alloc(chan); 807 if (ret < 0) { 808 nbpf_desc_put(desc); 809 return NULL; 810 } 811 spin_lock_irq(&chan->lock); 812 continue; 813 } 814 815 ldesc = list_first_entry(&chan->free_links, 816 struct nbpf_link_desc, node); 817 ldesc->desc = desc; 818 if (prev) 819 prev->hwdesc->next = (u32)ldesc->hwdesc_dma_addr; 820 821 prev = ldesc; 822 list_move_tail(&ldesc->node, &desc->sg); 823 824 i++; 825 } while (i < len); 826 } while (!desc); 827 828 prev->hwdesc->next = 0; 829 830 spin_unlock_irq(&chan->lock); 831 832 return desc; 833 } 834 835 static void nbpf_chan_idle(struct nbpf_channel *chan) 836 { 837 struct nbpf_desc *desc, *tmp; 838 unsigned long flags; 839 LIST_HEAD(head); 840 841 spin_lock_irqsave(&chan->lock, flags); 842 843 list_splice_init(&chan->done, &head); 844 list_splice_init(&chan->active, &head); 845 list_splice_init(&chan->queued, &head); 846 847 chan->running = NULL; 848 849 spin_unlock_irqrestore(&chan->lock, flags); 850 851 list_for_each_entry_safe(desc, tmp, &head, node) { 852 dev_dbg(chan->nbpf->dma_dev.dev, "%s(): force-free desc %p cookie %d\n", 853 __func__, desc, desc->async_tx.cookie); 854 list_del(&desc->node); 855 nbpf_desc_put(desc); 856 } 857 } 858 859 static int nbpf_pause(struct dma_chan *dchan) 860 { 861 struct nbpf_channel *chan = nbpf_to_chan(dchan); 862 863 dev_dbg(dchan->device->dev, "Entry %s\n", __func__); 864 865 chan->paused = true; 866 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_SETSUS); 867 /* See comment in nbpf_prep_one() */ 868 nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_CLREN); 869 870 return 0; 871 } 872 873 static int nbpf_terminate_all(struct dma_chan *dchan) 874 { 875 struct nbpf_channel *chan = nbpf_to_chan(dchan); 876 877 dev_dbg(dchan->device->dev, "Entry %s\n", __func__); 878 dev_dbg(dchan->device->dev, "Terminating\n"); 879 880 nbpf_chan_halt(chan); 881 nbpf_chan_idle(chan); 882 883 return 0; 884 } 885 886 static int nbpf_config(struct dma_chan *dchan, 887 struct dma_slave_config *config) 888 { 889 struct nbpf_channel *chan = nbpf_to_chan(dchan); 890 891 dev_dbg(dchan->device->dev, "Entry %s\n", __func__); 892 893 /* 894 * We could check config->slave_id to match chan->terminal here, 895 * but with DT they would be coming from the same source, so 896 * such a check would be superflous 897 */ 898 899 chan->slave_dst_addr = config->dst_addr; 900 chan->slave_dst_width = nbpf_xfer_size(chan->nbpf, 901 config->dst_addr_width, 1); 902 chan->slave_dst_burst = nbpf_xfer_size(chan->nbpf, 903 config->dst_addr_width, 904 config->dst_maxburst); 905 chan->slave_src_addr = config->src_addr; 906 chan->slave_src_width = nbpf_xfer_size(chan->nbpf, 907 config->src_addr_width, 1); 908 chan->slave_src_burst = nbpf_xfer_size(chan->nbpf, 909 config->src_addr_width, 910 config->src_maxburst); 911 912 return 0; 913 } 914 915 static struct dma_async_tx_descriptor *nbpf_prep_sg(struct nbpf_channel *chan, 916 struct scatterlist *src_sg, struct scatterlist *dst_sg, 917 size_t len, enum dma_transfer_direction direction, 918 unsigned long flags) 919 { 920 struct nbpf_link_desc *ldesc; 921 struct scatterlist *mem_sg; 922 struct nbpf_desc *desc; 923 bool inc_src, inc_dst; 924 size_t data_len = 0; 925 int i = 0; 926 927 switch (direction) { 928 case DMA_DEV_TO_MEM: 929 mem_sg = dst_sg; 930 inc_src = false; 931 inc_dst = true; 932 break; 933 934 case DMA_MEM_TO_DEV: 935 mem_sg = src_sg; 936 inc_src = true; 937 inc_dst = false; 938 break; 939 940 default: 941 case DMA_MEM_TO_MEM: 942 mem_sg = src_sg; 943 inc_src = true; 944 inc_dst = true; 945 } 946 947 desc = nbpf_desc_get(chan, len); 948 if (!desc) 949 return NULL; 950 951 desc->async_tx.flags = flags; 952 desc->async_tx.cookie = -EBUSY; 953 desc->user_wait = false; 954 955 /* 956 * This is a private descriptor list, and we own the descriptor. No need 957 * to lock. 958 */ 959 list_for_each_entry(ldesc, &desc->sg, node) { 960 int ret = nbpf_prep_one(ldesc, direction, 961 sg_dma_address(src_sg), 962 sg_dma_address(dst_sg), 963 sg_dma_len(mem_sg), 964 i == len - 1); 965 if (ret < 0) { 966 nbpf_desc_put(desc); 967 return NULL; 968 } 969 data_len += sg_dma_len(mem_sg); 970 if (inc_src) 971 src_sg = sg_next(src_sg); 972 if (inc_dst) 973 dst_sg = sg_next(dst_sg); 974 mem_sg = direction == DMA_DEV_TO_MEM ? dst_sg : src_sg; 975 i++; 976 } 977 978 desc->length = data_len; 979 980 /* The user has to return the descriptor to us ASAP via .tx_submit() */ 981 return &desc->async_tx; 982 } 983 984 static struct dma_async_tx_descriptor *nbpf_prep_memcpy( 985 struct dma_chan *dchan, dma_addr_t dst, dma_addr_t src, 986 size_t len, unsigned long flags) 987 { 988 struct nbpf_channel *chan = nbpf_to_chan(dchan); 989 struct scatterlist dst_sg; 990 struct scatterlist src_sg; 991 992 sg_init_table(&dst_sg, 1); 993 sg_init_table(&src_sg, 1); 994 995 sg_dma_address(&dst_sg) = dst; 996 sg_dma_address(&src_sg) = src; 997 998 sg_dma_len(&dst_sg) = len; 999 sg_dma_len(&src_sg) = len; 1000 1001 dev_dbg(dchan->device->dev, "%s(): %zu @ %pad -> %pad\n", 1002 __func__, len, &src, &dst); 1003 1004 return nbpf_prep_sg(chan, &src_sg, &dst_sg, 1, 1005 DMA_MEM_TO_MEM, flags); 1006 } 1007 1008 static struct dma_async_tx_descriptor *nbpf_prep_slave_sg( 1009 struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len, 1010 enum dma_transfer_direction direction, unsigned long flags, void *context) 1011 { 1012 struct nbpf_channel *chan = nbpf_to_chan(dchan); 1013 struct scatterlist slave_sg; 1014 1015 dev_dbg(dchan->device->dev, "Entry %s()\n", __func__); 1016 1017 sg_init_table(&slave_sg, 1); 1018 1019 switch (direction) { 1020 case DMA_MEM_TO_DEV: 1021 sg_dma_address(&slave_sg) = chan->slave_dst_addr; 1022 return nbpf_prep_sg(chan, sgl, &slave_sg, sg_len, 1023 direction, flags); 1024 1025 case DMA_DEV_TO_MEM: 1026 sg_dma_address(&slave_sg) = chan->slave_src_addr; 1027 return nbpf_prep_sg(chan, &slave_sg, sgl, sg_len, 1028 direction, flags); 1029 1030 default: 1031 return NULL; 1032 } 1033 } 1034 1035 static int nbpf_alloc_chan_resources(struct dma_chan *dchan) 1036 { 1037 struct nbpf_channel *chan = nbpf_to_chan(dchan); 1038 int ret; 1039 1040 INIT_LIST_HEAD(&chan->free); 1041 INIT_LIST_HEAD(&chan->free_links); 1042 INIT_LIST_HEAD(&chan->queued); 1043 INIT_LIST_HEAD(&chan->active); 1044 INIT_LIST_HEAD(&chan->done); 1045 1046 ret = nbpf_desc_page_alloc(chan); 1047 if (ret < 0) 1048 return ret; 1049 1050 dev_dbg(dchan->device->dev, "Entry %s(): terminal %u\n", __func__, 1051 chan->terminal); 1052 1053 nbpf_chan_configure(chan); 1054 1055 return ret; 1056 } 1057 1058 static void nbpf_free_chan_resources(struct dma_chan *dchan) 1059 { 1060 struct nbpf_channel *chan = nbpf_to_chan(dchan); 1061 struct nbpf_desc_page *dpage, *tmp; 1062 1063 dev_dbg(dchan->device->dev, "Entry %s()\n", __func__); 1064 1065 nbpf_chan_halt(chan); 1066 nbpf_chan_idle(chan); 1067 /* Clean up for if a channel is re-used for MEMCPY after slave DMA */ 1068 nbpf_chan_prepare_default(chan); 1069 1070 list_for_each_entry_safe(dpage, tmp, &chan->desc_page, node) { 1071 struct nbpf_link_desc *ldesc; 1072 int i; 1073 list_del(&dpage->node); 1074 for (i = 0, ldesc = dpage->ldesc; 1075 i < ARRAY_SIZE(dpage->ldesc); 1076 i++, ldesc++) 1077 dma_unmap_single(dchan->device->dev, ldesc->hwdesc_dma_addr, 1078 sizeof(*ldesc->hwdesc), DMA_TO_DEVICE); 1079 free_page((unsigned long)dpage); 1080 } 1081 } 1082 1083 static struct dma_chan *nbpf_of_xlate(struct of_phandle_args *dma_spec, 1084 struct of_dma *ofdma) 1085 { 1086 struct nbpf_device *nbpf = ofdma->of_dma_data; 1087 struct dma_chan *dchan; 1088 struct nbpf_channel *chan; 1089 1090 if (dma_spec->args_count != 2) 1091 return NULL; 1092 1093 dchan = dma_get_any_slave_channel(&nbpf->dma_dev); 1094 if (!dchan) 1095 return NULL; 1096 1097 dev_dbg(dchan->device->dev, "Entry %s(%s)\n", __func__, 1098 dma_spec->np->name); 1099 1100 chan = nbpf_to_chan(dchan); 1101 1102 chan->terminal = dma_spec->args[0]; 1103 chan->flags = dma_spec->args[1]; 1104 1105 nbpf_chan_prepare(chan); 1106 nbpf_chan_configure(chan); 1107 1108 return dchan; 1109 } 1110 1111 static void nbpf_chan_tasklet(unsigned long data) 1112 { 1113 struct nbpf_channel *chan = (struct nbpf_channel *)data; 1114 struct nbpf_desc *desc, *tmp; 1115 struct dmaengine_desc_callback cb; 1116 1117 while (!list_empty(&chan->done)) { 1118 bool found = false, must_put, recycling = false; 1119 1120 spin_lock_irq(&chan->lock); 1121 1122 list_for_each_entry_safe(desc, tmp, &chan->done, node) { 1123 if (!desc->user_wait) { 1124 /* Newly completed descriptor, have to process */ 1125 found = true; 1126 break; 1127 } else if (async_tx_test_ack(&desc->async_tx)) { 1128 /* 1129 * This descriptor was waiting for a user ACK, 1130 * it can be recycled now. 1131 */ 1132 list_del(&desc->node); 1133 spin_unlock_irq(&chan->lock); 1134 nbpf_desc_put(desc); 1135 recycling = true; 1136 break; 1137 } 1138 } 1139 1140 if (recycling) 1141 continue; 1142 1143 if (!found) { 1144 /* This can happen if TERMINATE_ALL has been called */ 1145 spin_unlock_irq(&chan->lock); 1146 break; 1147 } 1148 1149 dma_cookie_complete(&desc->async_tx); 1150 1151 /* 1152 * With released lock we cannot dereference desc, maybe it's 1153 * still on the "done" list 1154 */ 1155 if (async_tx_test_ack(&desc->async_tx)) { 1156 list_del(&desc->node); 1157 must_put = true; 1158 } else { 1159 desc->user_wait = true; 1160 must_put = false; 1161 } 1162 1163 dmaengine_desc_get_callback(&desc->async_tx, &cb); 1164 1165 /* ack and callback completed descriptor */ 1166 spin_unlock_irq(&chan->lock); 1167 1168 dmaengine_desc_callback_invoke(&cb, NULL); 1169 1170 if (must_put) 1171 nbpf_desc_put(desc); 1172 } 1173 } 1174 1175 static irqreturn_t nbpf_chan_irq(int irq, void *dev) 1176 { 1177 struct nbpf_channel *chan = dev; 1178 bool done = nbpf_status_get(chan); 1179 struct nbpf_desc *desc; 1180 irqreturn_t ret; 1181 bool bh = false; 1182 1183 if (!done) 1184 return IRQ_NONE; 1185 1186 nbpf_status_ack(chan); 1187 1188 dev_dbg(&chan->dma_chan.dev->device, "%s()\n", __func__); 1189 1190 spin_lock(&chan->lock); 1191 desc = chan->running; 1192 if (WARN_ON(!desc)) { 1193 ret = IRQ_NONE; 1194 goto unlock; 1195 } else { 1196 ret = IRQ_HANDLED; 1197 bh = true; 1198 } 1199 1200 list_move_tail(&desc->node, &chan->done); 1201 chan->running = NULL; 1202 1203 if (!list_empty(&chan->active)) { 1204 desc = list_first_entry(&chan->active, 1205 struct nbpf_desc, node); 1206 if (!nbpf_start(desc)) 1207 chan->running = desc; 1208 } 1209 1210 unlock: 1211 spin_unlock(&chan->lock); 1212 1213 if (bh) 1214 tasklet_schedule(&chan->tasklet); 1215 1216 return ret; 1217 } 1218 1219 static irqreturn_t nbpf_err_irq(int irq, void *dev) 1220 { 1221 struct nbpf_device *nbpf = dev; 1222 u32 error = nbpf_error_get(nbpf); 1223 1224 dev_warn(nbpf->dma_dev.dev, "DMA error IRQ %u\n", irq); 1225 1226 if (!error) 1227 return IRQ_NONE; 1228 1229 do { 1230 struct nbpf_channel *chan = nbpf_error_get_channel(nbpf, error); 1231 /* On error: abort all queued transfers, no callback */ 1232 nbpf_error_clear(chan); 1233 nbpf_chan_idle(chan); 1234 error = nbpf_error_get(nbpf); 1235 } while (error); 1236 1237 return IRQ_HANDLED; 1238 } 1239 1240 static int nbpf_chan_probe(struct nbpf_device *nbpf, int n) 1241 { 1242 struct dma_device *dma_dev = &nbpf->dma_dev; 1243 struct nbpf_channel *chan = nbpf->chan + n; 1244 int ret; 1245 1246 chan->nbpf = nbpf; 1247 chan->base = nbpf->base + NBPF_REG_CHAN_OFFSET + NBPF_REG_CHAN_SIZE * n; 1248 INIT_LIST_HEAD(&chan->desc_page); 1249 spin_lock_init(&chan->lock); 1250 chan->dma_chan.device = dma_dev; 1251 dma_cookie_init(&chan->dma_chan); 1252 nbpf_chan_prepare_default(chan); 1253 1254 dev_dbg(dma_dev->dev, "%s(): channel %d: -> %p\n", __func__, n, chan->base); 1255 1256 snprintf(chan->name, sizeof(chan->name), "nbpf %d", n); 1257 1258 tasklet_init(&chan->tasklet, nbpf_chan_tasklet, (unsigned long)chan); 1259 ret = devm_request_irq(dma_dev->dev, chan->irq, 1260 nbpf_chan_irq, IRQF_SHARED, 1261 chan->name, chan); 1262 if (ret < 0) 1263 return ret; 1264 1265 /* Add the channel to DMA device channel list */ 1266 list_add_tail(&chan->dma_chan.device_node, 1267 &dma_dev->channels); 1268 1269 return 0; 1270 } 1271 1272 static const struct of_device_id nbpf_match[] = { 1273 {.compatible = "renesas,nbpfaxi64dmac1b4", .data = &nbpf_cfg[NBPF1B4]}, 1274 {.compatible = "renesas,nbpfaxi64dmac1b8", .data = &nbpf_cfg[NBPF1B8]}, 1275 {.compatible = "renesas,nbpfaxi64dmac1b16", .data = &nbpf_cfg[NBPF1B16]}, 1276 {.compatible = "renesas,nbpfaxi64dmac4b4", .data = &nbpf_cfg[NBPF4B4]}, 1277 {.compatible = "renesas,nbpfaxi64dmac4b8", .data = &nbpf_cfg[NBPF4B8]}, 1278 {.compatible = "renesas,nbpfaxi64dmac4b16", .data = &nbpf_cfg[NBPF4B16]}, 1279 {.compatible = "renesas,nbpfaxi64dmac8b4", .data = &nbpf_cfg[NBPF8B4]}, 1280 {.compatible = "renesas,nbpfaxi64dmac8b8", .data = &nbpf_cfg[NBPF8B8]}, 1281 {.compatible = "renesas,nbpfaxi64dmac8b16", .data = &nbpf_cfg[NBPF8B16]}, 1282 {} 1283 }; 1284 MODULE_DEVICE_TABLE(of, nbpf_match); 1285 1286 static int nbpf_probe(struct platform_device *pdev) 1287 { 1288 struct device *dev = &pdev->dev; 1289 const struct of_device_id *of_id = of_match_device(nbpf_match, dev); 1290 struct device_node *np = dev->of_node; 1291 struct nbpf_device *nbpf; 1292 struct dma_device *dma_dev; 1293 struct resource *iomem, *irq_res; 1294 const struct nbpf_config *cfg; 1295 int num_channels; 1296 int ret, irq, eirq, i; 1297 int irqbuf[9] /* maximum 8 channels + error IRQ */; 1298 unsigned int irqs = 0; 1299 1300 BUILD_BUG_ON(sizeof(struct nbpf_desc_page) > PAGE_SIZE); 1301 1302 /* DT only */ 1303 if (!np || !of_id || !of_id->data) 1304 return -ENODEV; 1305 1306 cfg = of_id->data; 1307 num_channels = cfg->num_channels; 1308 1309 nbpf = devm_kzalloc(dev, sizeof(*nbpf) + num_channels * 1310 sizeof(nbpf->chan[0]), GFP_KERNEL); 1311 if (!nbpf) 1312 return -ENOMEM; 1313 1314 dma_dev = &nbpf->dma_dev; 1315 dma_dev->dev = dev; 1316 1317 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1318 nbpf->base = devm_ioremap_resource(dev, iomem); 1319 if (IS_ERR(nbpf->base)) 1320 return PTR_ERR(nbpf->base); 1321 1322 nbpf->clk = devm_clk_get(dev, NULL); 1323 if (IS_ERR(nbpf->clk)) 1324 return PTR_ERR(nbpf->clk); 1325 1326 of_property_read_u32(np, "max-burst-mem-read", 1327 &nbpf->max_burst_mem_read); 1328 of_property_read_u32(np, "max-burst-mem-write", 1329 &nbpf->max_burst_mem_write); 1330 1331 nbpf->config = cfg; 1332 1333 for (i = 0; irqs < ARRAY_SIZE(irqbuf); i++) { 1334 irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, i); 1335 if (!irq_res) 1336 break; 1337 1338 for (irq = irq_res->start; irq <= irq_res->end; 1339 irq++, irqs++) 1340 irqbuf[irqs] = irq; 1341 } 1342 1343 /* 1344 * 3 IRQ resource schemes are supported: 1345 * 1. 1 shared IRQ for error and all channels 1346 * 2. 2 IRQs: one for error and one shared for all channels 1347 * 3. 1 IRQ for error and an own IRQ for each channel 1348 */ 1349 if (irqs != 1 && irqs != 2 && irqs != num_channels + 1) 1350 return -ENXIO; 1351 1352 if (irqs == 1) { 1353 eirq = irqbuf[0]; 1354 1355 for (i = 0; i <= num_channels; i++) 1356 nbpf->chan[i].irq = irqbuf[0]; 1357 } else { 1358 eirq = platform_get_irq_byname(pdev, "error"); 1359 if (eirq < 0) 1360 return eirq; 1361 1362 if (irqs == num_channels + 1) { 1363 struct nbpf_channel *chan; 1364 1365 for (i = 0, chan = nbpf->chan; i <= num_channels; 1366 i++, chan++) { 1367 /* Skip the error IRQ */ 1368 if (irqbuf[i] == eirq) 1369 i++; 1370 chan->irq = irqbuf[i]; 1371 } 1372 1373 if (chan != nbpf->chan + num_channels) 1374 return -EINVAL; 1375 } else { 1376 /* 2 IRQs and more than one channel */ 1377 if (irqbuf[0] == eirq) 1378 irq = irqbuf[1]; 1379 else 1380 irq = irqbuf[0]; 1381 1382 for (i = 0; i <= num_channels; i++) 1383 nbpf->chan[i].irq = irq; 1384 } 1385 } 1386 1387 ret = devm_request_irq(dev, eirq, nbpf_err_irq, 1388 IRQF_SHARED, "dma error", nbpf); 1389 if (ret < 0) 1390 return ret; 1391 nbpf->eirq = eirq; 1392 1393 INIT_LIST_HEAD(&dma_dev->channels); 1394 1395 /* Create DMA Channel */ 1396 for (i = 0; i < num_channels; i++) { 1397 ret = nbpf_chan_probe(nbpf, i); 1398 if (ret < 0) 1399 return ret; 1400 } 1401 1402 dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); 1403 dma_cap_set(DMA_SLAVE, dma_dev->cap_mask); 1404 dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask); 1405 1406 /* Common and MEMCPY operations */ 1407 dma_dev->device_alloc_chan_resources 1408 = nbpf_alloc_chan_resources; 1409 dma_dev->device_free_chan_resources = nbpf_free_chan_resources; 1410 dma_dev->device_prep_dma_memcpy = nbpf_prep_memcpy; 1411 dma_dev->device_tx_status = nbpf_tx_status; 1412 dma_dev->device_issue_pending = nbpf_issue_pending; 1413 1414 /* 1415 * If we drop support for unaligned MEMCPY buffer addresses and / or 1416 * lengths by setting 1417 * dma_dev->copy_align = 4; 1418 * then we can set transfer length to 4 bytes in nbpf_prep_one() for 1419 * DMA_MEM_TO_MEM 1420 */ 1421 1422 /* Compulsory for DMA_SLAVE fields */ 1423 dma_dev->device_prep_slave_sg = nbpf_prep_slave_sg; 1424 dma_dev->device_config = nbpf_config; 1425 dma_dev->device_pause = nbpf_pause; 1426 dma_dev->device_terminate_all = nbpf_terminate_all; 1427 1428 dma_dev->src_addr_widths = NBPF_DMA_BUSWIDTHS; 1429 dma_dev->dst_addr_widths = NBPF_DMA_BUSWIDTHS; 1430 dma_dev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); 1431 1432 platform_set_drvdata(pdev, nbpf); 1433 1434 ret = clk_prepare_enable(nbpf->clk); 1435 if (ret < 0) 1436 return ret; 1437 1438 nbpf_configure(nbpf); 1439 1440 ret = dma_async_device_register(dma_dev); 1441 if (ret < 0) 1442 goto e_clk_off; 1443 1444 ret = of_dma_controller_register(np, nbpf_of_xlate, nbpf); 1445 if (ret < 0) 1446 goto e_dma_dev_unreg; 1447 1448 return 0; 1449 1450 e_dma_dev_unreg: 1451 dma_async_device_unregister(dma_dev); 1452 e_clk_off: 1453 clk_disable_unprepare(nbpf->clk); 1454 1455 return ret; 1456 } 1457 1458 static int nbpf_remove(struct platform_device *pdev) 1459 { 1460 struct nbpf_device *nbpf = platform_get_drvdata(pdev); 1461 int i; 1462 1463 devm_free_irq(&pdev->dev, nbpf->eirq, nbpf); 1464 1465 for (i = 0; i < nbpf->config->num_channels; i++) { 1466 struct nbpf_channel *chan = nbpf->chan + i; 1467 1468 devm_free_irq(&pdev->dev, chan->irq, chan); 1469 1470 tasklet_kill(&chan->tasklet); 1471 } 1472 1473 of_dma_controller_free(pdev->dev.of_node); 1474 dma_async_device_unregister(&nbpf->dma_dev); 1475 clk_disable_unprepare(nbpf->clk); 1476 1477 return 0; 1478 } 1479 1480 static const struct platform_device_id nbpf_ids[] = { 1481 {"nbpfaxi64dmac1b4", (kernel_ulong_t)&nbpf_cfg[NBPF1B4]}, 1482 {"nbpfaxi64dmac1b8", (kernel_ulong_t)&nbpf_cfg[NBPF1B8]}, 1483 {"nbpfaxi64dmac1b16", (kernel_ulong_t)&nbpf_cfg[NBPF1B16]}, 1484 {"nbpfaxi64dmac4b4", (kernel_ulong_t)&nbpf_cfg[NBPF4B4]}, 1485 {"nbpfaxi64dmac4b8", (kernel_ulong_t)&nbpf_cfg[NBPF4B8]}, 1486 {"nbpfaxi64dmac4b16", (kernel_ulong_t)&nbpf_cfg[NBPF4B16]}, 1487 {"nbpfaxi64dmac8b4", (kernel_ulong_t)&nbpf_cfg[NBPF8B4]}, 1488 {"nbpfaxi64dmac8b8", (kernel_ulong_t)&nbpf_cfg[NBPF8B8]}, 1489 {"nbpfaxi64dmac8b16", (kernel_ulong_t)&nbpf_cfg[NBPF8B16]}, 1490 {}, 1491 }; 1492 MODULE_DEVICE_TABLE(platform, nbpf_ids); 1493 1494 #ifdef CONFIG_PM 1495 static int nbpf_runtime_suspend(struct device *dev) 1496 { 1497 struct nbpf_device *nbpf = platform_get_drvdata(to_platform_device(dev)); 1498 clk_disable_unprepare(nbpf->clk); 1499 return 0; 1500 } 1501 1502 static int nbpf_runtime_resume(struct device *dev) 1503 { 1504 struct nbpf_device *nbpf = platform_get_drvdata(to_platform_device(dev)); 1505 return clk_prepare_enable(nbpf->clk); 1506 } 1507 #endif 1508 1509 static const struct dev_pm_ops nbpf_pm_ops = { 1510 SET_RUNTIME_PM_OPS(nbpf_runtime_suspend, nbpf_runtime_resume, NULL) 1511 }; 1512 1513 static struct platform_driver nbpf_driver = { 1514 .driver = { 1515 .name = "dma-nbpf", 1516 .of_match_table = nbpf_match, 1517 .pm = &nbpf_pm_ops, 1518 }, 1519 .id_table = nbpf_ids, 1520 .probe = nbpf_probe, 1521 .remove = nbpf_remove, 1522 }; 1523 1524 module_platform_driver(nbpf_driver); 1525 1526 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>"); 1527 MODULE_DESCRIPTION("dmaengine driver for NBPFAXI64* DMACs"); 1528 MODULE_LICENSE("GPL v2"); 1529