1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/arch/arm/plat-omap/dma.c 4 * 5 * Copyright (C) 2003 - 2008 Nokia Corporation 6 * Author: Juha Yrjölä <juha.yrjola@nokia.com> 7 * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com> 8 * Graphics DMA and LCD DMA graphics tranformations 9 * by Imre Deak <imre.deak@nokia.com> 10 * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc. 11 * Merged to support both OMAP1 and OMAP2 by Tony Lindgren <tony@atomide.com> 12 * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc. 13 * 14 * Copyright (C) 2009 Texas Instruments 15 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com> 16 * 17 * Support functions for the OMAP internal DMA channels. 18 * 19 * Copyright (C) 2010 Texas Instruments Incorporated - https://www.ti.com/ 20 * Converted DMA library into DMA platform driver. 21 * - G, Manjunath Kondaiah <manjugk@ti.com> 22 */ 23 24 #include <linux/module.h> 25 #include <linux/init.h> 26 #include <linux/sched.h> 27 #include <linux/spinlock.h> 28 #include <linux/errno.h> 29 #include <linux/interrupt.h> 30 #include <linux/irq.h> 31 #include <linux/io.h> 32 #include <linux/slab.h> 33 #include <linux/delay.h> 34 35 #include <linux/omap-dma.h> 36 37 #include <linux/soc/ti/omap1-io.h> 38 #include <linux/soc/ti/omap1-soc.h> 39 40 #include "tc.h" 41 42 /* 43 * MAX_LOGICAL_DMA_CH_COUNT: the maximum number of logical DMA 44 * channels that an instance of the SDMA IP block can support. Used 45 * to size arrays. (The actual maximum on a particular SoC may be less 46 * than this -- for example, OMAP1 SDMA instances only support 17 logical 47 * DMA channels.) 48 */ 49 #define MAX_LOGICAL_DMA_CH_COUNT 32 50 51 #undef DEBUG 52 53 #define OMAP_DMA_ACTIVE 0x01 54 55 #define OMAP_FUNC_MUX_ARM_BASE (0xfffe1000 + 0xec) 56 57 static struct omap_system_dma_plat_info *p; 58 static struct omap_dma_dev_attr *d; 59 static int enable_1510_mode; 60 static u32 errata; 61 62 struct dma_link_info { 63 int *linked_dmach_q; 64 int no_of_lchs_linked; 65 66 int q_count; 67 int q_tail; 68 int q_head; 69 70 int chain_state; 71 int chain_mode; 72 73 }; 74 75 static int dma_lch_count; 76 static int dma_chan_count; 77 static int omap_dma_reserve_channels; 78 79 static DEFINE_SPINLOCK(dma_chan_lock); 80 static struct omap_dma_lch *dma_chan; 81 omap_disable_channel_irq(int lch)82 static inline void omap_disable_channel_irq(int lch) 83 { 84 /* disable channel interrupts */ 85 p->dma_write(0, CICR, lch); 86 /* Clear CSR */ 87 p->dma_read(CSR, lch); 88 } 89 set_gdma_dev(int req,int dev)90 static inline void set_gdma_dev(int req, int dev) 91 { 92 u32 reg = OMAP_FUNC_MUX_ARM_BASE + ((req - 1) / 5) * 4; 93 int shift = ((req - 1) % 5) * 6; 94 u32 l; 95 96 l = omap_readl(reg); 97 l &= ~(0x3f << shift); 98 l |= (dev - 1) << shift; 99 omap_writel(l, reg); 100 } 101 102 #if IS_ENABLED(CONFIG_FB_OMAP) omap_set_dma_priority(int lch,int dst_port,int priority)103 void omap_set_dma_priority(int lch, int dst_port, int priority) 104 { 105 unsigned long reg; 106 u32 l; 107 108 if (dma_omap1()) { 109 switch (dst_port) { 110 case OMAP_DMA_PORT_OCP_T1: /* FFFECC00 */ 111 reg = OMAP_TC_OCPT1_PRIOR; 112 break; 113 case OMAP_DMA_PORT_OCP_T2: /* FFFECCD0 */ 114 reg = OMAP_TC_OCPT2_PRIOR; 115 break; 116 case OMAP_DMA_PORT_EMIFF: /* FFFECC08 */ 117 reg = OMAP_TC_EMIFF_PRIOR; 118 break; 119 case OMAP_DMA_PORT_EMIFS: /* FFFECC04 */ 120 reg = OMAP_TC_EMIFS_PRIOR; 121 break; 122 default: 123 BUG(); 124 return; 125 } 126 l = omap_readl(reg); 127 l &= ~(0xf << 8); 128 l |= (priority & 0xf) << 8; 129 omap_writel(l, reg); 130 } 131 } 132 EXPORT_SYMBOL(omap_set_dma_priority); 133 #endif 134 135 #if IS_ENABLED(CONFIG_USB_OMAP) 136 #ifdef CONFIG_ARCH_OMAP15XX 137 /* Returns 1 if the DMA module is in OMAP1510-compatible mode, 0 otherwise */ omap_dma_in_1510_mode(void)138 static int omap_dma_in_1510_mode(void) 139 { 140 return enable_1510_mode; 141 } 142 #else 143 #define omap_dma_in_1510_mode() 0 144 #endif 145 omap_set_dma_transfer_params(int lch,int data_type,int elem_count,int frame_count,int sync_mode,int dma_trigger,int src_or_dst_synch)146 void omap_set_dma_transfer_params(int lch, int data_type, int elem_count, 147 int frame_count, int sync_mode, 148 int dma_trigger, int src_or_dst_synch) 149 { 150 u32 l; 151 u16 ccr; 152 153 l = p->dma_read(CSDP, lch); 154 l &= ~0x03; 155 l |= data_type; 156 p->dma_write(l, CSDP, lch); 157 158 ccr = p->dma_read(CCR, lch); 159 ccr &= ~(1 << 5); 160 if (sync_mode == OMAP_DMA_SYNC_FRAME) 161 ccr |= 1 << 5; 162 p->dma_write(ccr, CCR, lch); 163 164 ccr = p->dma_read(CCR2, lch); 165 ccr &= ~(1 << 2); 166 if (sync_mode == OMAP_DMA_SYNC_BLOCK) 167 ccr |= 1 << 2; 168 p->dma_write(ccr, CCR2, lch); 169 p->dma_write(elem_count, CEN, lch); 170 p->dma_write(frame_count, CFN, lch); 171 } 172 EXPORT_SYMBOL(omap_set_dma_transfer_params); 173 omap_set_dma_channel_mode(int lch,enum omap_dma_channel_mode mode)174 void omap_set_dma_channel_mode(int lch, enum omap_dma_channel_mode mode) 175 { 176 if (!dma_omap15xx()) { 177 u32 l; 178 179 l = p->dma_read(LCH_CTRL, lch); 180 l &= ~0x7; 181 l |= mode; 182 p->dma_write(l, LCH_CTRL, lch); 183 } 184 } 185 EXPORT_SYMBOL(omap_set_dma_channel_mode); 186 187 /* Note that src_port is only for omap1 */ omap_set_dma_src_params(int lch,int src_port,int src_amode,unsigned long src_start,int src_ei,int src_fi)188 void omap_set_dma_src_params(int lch, int src_port, int src_amode, 189 unsigned long src_start, 190 int src_ei, int src_fi) 191 { 192 u32 l; 193 u16 w; 194 195 w = p->dma_read(CSDP, lch); 196 w &= ~(0x1f << 2); 197 w |= src_port << 2; 198 p->dma_write(w, CSDP, lch); 199 200 l = p->dma_read(CCR, lch); 201 l &= ~(0x03 << 12); 202 l |= src_amode << 12; 203 p->dma_write(l, CCR, lch); 204 205 p->dma_write(src_start, CSSA, lch); 206 207 p->dma_write(src_ei, CSEI, lch); 208 p->dma_write(src_fi, CSFI, lch); 209 } 210 EXPORT_SYMBOL(omap_set_dma_src_params); 211 omap_set_dma_src_data_pack(int lch,int enable)212 void omap_set_dma_src_data_pack(int lch, int enable) 213 { 214 u32 l; 215 216 l = p->dma_read(CSDP, lch); 217 l &= ~(1 << 6); 218 if (enable) 219 l |= (1 << 6); 220 p->dma_write(l, CSDP, lch); 221 } 222 EXPORT_SYMBOL(omap_set_dma_src_data_pack); 223 omap_set_dma_src_burst_mode(int lch,enum omap_dma_burst_mode burst_mode)224 void omap_set_dma_src_burst_mode(int lch, enum omap_dma_burst_mode burst_mode) 225 { 226 unsigned int burst = 0; 227 u32 l; 228 229 l = p->dma_read(CSDP, lch); 230 l &= ~(0x03 << 7); 231 232 switch (burst_mode) { 233 case OMAP_DMA_DATA_BURST_DIS: 234 break; 235 case OMAP_DMA_DATA_BURST_4: 236 burst = 0x2; 237 break; 238 case OMAP_DMA_DATA_BURST_8: 239 /* 240 * not supported by current hardware on OMAP1 241 * w |= (0x03 << 7); 242 */ 243 fallthrough; 244 case OMAP_DMA_DATA_BURST_16: 245 /* OMAP1 don't support burst 16 */ 246 fallthrough; 247 default: 248 BUG(); 249 } 250 251 l |= (burst << 7); 252 p->dma_write(l, CSDP, lch); 253 } 254 EXPORT_SYMBOL(omap_set_dma_src_burst_mode); 255 256 /* Note that dest_port is only for OMAP1 */ omap_set_dma_dest_params(int lch,int dest_port,int dest_amode,unsigned long dest_start,int dst_ei,int dst_fi)257 void omap_set_dma_dest_params(int lch, int dest_port, int dest_amode, 258 unsigned long dest_start, 259 int dst_ei, int dst_fi) 260 { 261 u32 l; 262 263 l = p->dma_read(CSDP, lch); 264 l &= ~(0x1f << 9); 265 l |= dest_port << 9; 266 p->dma_write(l, CSDP, lch); 267 268 l = p->dma_read(CCR, lch); 269 l &= ~(0x03 << 14); 270 l |= dest_amode << 14; 271 p->dma_write(l, CCR, lch); 272 273 p->dma_write(dest_start, CDSA, lch); 274 275 p->dma_write(dst_ei, CDEI, lch); 276 p->dma_write(dst_fi, CDFI, lch); 277 } 278 EXPORT_SYMBOL(omap_set_dma_dest_params); 279 omap_set_dma_dest_data_pack(int lch,int enable)280 void omap_set_dma_dest_data_pack(int lch, int enable) 281 { 282 u32 l; 283 284 l = p->dma_read(CSDP, lch); 285 l &= ~(1 << 13); 286 if (enable) 287 l |= 1 << 13; 288 p->dma_write(l, CSDP, lch); 289 } 290 EXPORT_SYMBOL(omap_set_dma_dest_data_pack); 291 omap_set_dma_dest_burst_mode(int lch,enum omap_dma_burst_mode burst_mode)292 void omap_set_dma_dest_burst_mode(int lch, enum omap_dma_burst_mode burst_mode) 293 { 294 unsigned int burst = 0; 295 u32 l; 296 297 l = p->dma_read(CSDP, lch); 298 l &= ~(0x03 << 14); 299 300 switch (burst_mode) { 301 case OMAP_DMA_DATA_BURST_DIS: 302 break; 303 case OMAP_DMA_DATA_BURST_4: 304 burst = 0x2; 305 break; 306 case OMAP_DMA_DATA_BURST_8: 307 burst = 0x3; 308 break; 309 case OMAP_DMA_DATA_BURST_16: 310 /* OMAP1 don't support burst 16 */ 311 fallthrough; 312 default: 313 printk(KERN_ERR "Invalid DMA burst mode\n"); 314 BUG(); 315 return; 316 } 317 l |= (burst << 14); 318 p->dma_write(l, CSDP, lch); 319 } 320 EXPORT_SYMBOL(omap_set_dma_dest_burst_mode); 321 omap_enable_channel_irq(int lch)322 static inline void omap_enable_channel_irq(int lch) 323 { 324 /* Clear CSR */ 325 p->dma_read(CSR, lch); 326 327 /* Enable some nice interrupts. */ 328 p->dma_write(dma_chan[lch].enabled_irqs, CICR, lch); 329 } 330 omap_disable_dma_irq(int lch,u16 bits)331 void omap_disable_dma_irq(int lch, u16 bits) 332 { 333 dma_chan[lch].enabled_irqs &= ~bits; 334 } 335 EXPORT_SYMBOL(omap_disable_dma_irq); 336 enable_lnk(int lch)337 static inline void enable_lnk(int lch) 338 { 339 u32 l; 340 341 l = p->dma_read(CLNK_CTRL, lch); 342 343 l &= ~(1 << 14); 344 345 /* Set the ENABLE_LNK bits */ 346 if (dma_chan[lch].next_lch != -1) 347 l = dma_chan[lch].next_lch | (1 << 15); 348 349 p->dma_write(l, CLNK_CTRL, lch); 350 } 351 disable_lnk(int lch)352 static inline void disable_lnk(int lch) 353 { 354 u32 l; 355 356 l = p->dma_read(CLNK_CTRL, lch); 357 358 /* Disable interrupts */ 359 omap_disable_channel_irq(lch); 360 361 /* Set the STOP_LNK bit */ 362 l |= 1 << 14; 363 364 p->dma_write(l, CLNK_CTRL, lch); 365 dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE; 366 } 367 #endif 368 omap_request_dma(int dev_id,const char * dev_name,void (* callback)(int lch,u16 ch_status,void * data),void * data,int * dma_ch_out)369 int omap_request_dma(int dev_id, const char *dev_name, 370 void (*callback)(int lch, u16 ch_status, void *data), 371 void *data, int *dma_ch_out) 372 { 373 int ch, free_ch = -1; 374 unsigned long flags; 375 struct omap_dma_lch *chan; 376 377 WARN(strcmp(dev_name, "DMA engine"), "Using deprecated platform DMA API - please update to DMA engine"); 378 379 spin_lock_irqsave(&dma_chan_lock, flags); 380 for (ch = 0; ch < dma_chan_count; ch++) { 381 if (free_ch == -1 && dma_chan[ch].dev_id == -1) { 382 free_ch = ch; 383 /* Exit after first free channel found */ 384 break; 385 } 386 } 387 if (free_ch == -1) { 388 spin_unlock_irqrestore(&dma_chan_lock, flags); 389 return -EBUSY; 390 } 391 chan = dma_chan + free_ch; 392 chan->dev_id = dev_id; 393 394 if (p->clear_lch_regs) 395 p->clear_lch_regs(free_ch); 396 397 spin_unlock_irqrestore(&dma_chan_lock, flags); 398 399 chan->dev_name = dev_name; 400 chan->callback = callback; 401 chan->data = data; 402 chan->flags = 0; 403 404 chan->enabled_irqs = OMAP_DMA_DROP_IRQ | OMAP_DMA_BLOCK_IRQ; 405 406 chan->enabled_irqs |= OMAP1_DMA_TOUT_IRQ; 407 408 if (dma_omap16xx()) { 409 /* If the sync device is set, configure it dynamically. */ 410 if (dev_id != 0) { 411 set_gdma_dev(free_ch + 1, dev_id); 412 dev_id = free_ch + 1; 413 } 414 /* 415 * Disable the 1510 compatibility mode and set the sync device 416 * id. 417 */ 418 p->dma_write(dev_id | (1 << 10), CCR, free_ch); 419 } else { 420 p->dma_write(dev_id, CCR, free_ch); 421 } 422 423 *dma_ch_out = free_ch; 424 425 return 0; 426 } 427 EXPORT_SYMBOL(omap_request_dma); 428 omap_free_dma(int lch)429 void omap_free_dma(int lch) 430 { 431 unsigned long flags; 432 433 if (dma_chan[lch].dev_id == -1) { 434 pr_err("omap_dma: trying to free unallocated DMA channel %d\n", 435 lch); 436 return; 437 } 438 439 /* Disable all DMA interrupts for the channel. */ 440 omap_disable_channel_irq(lch); 441 442 /* Make sure the DMA transfer is stopped. */ 443 p->dma_write(0, CCR, lch); 444 445 spin_lock_irqsave(&dma_chan_lock, flags); 446 dma_chan[lch].dev_id = -1; 447 dma_chan[lch].next_lch = -1; 448 dma_chan[lch].callback = NULL; 449 spin_unlock_irqrestore(&dma_chan_lock, flags); 450 } 451 EXPORT_SYMBOL(omap_free_dma); 452 453 /* 454 * Clears any DMA state so the DMA engine is ready to restart with new buffers 455 * through omap_start_dma(). Any buffers in flight are discarded. 456 */ omap_clear_dma(int lch)457 static void omap_clear_dma(int lch) 458 { 459 unsigned long flags; 460 461 local_irq_save(flags); 462 p->clear_dma(lch); 463 local_irq_restore(flags); 464 } 465 466 #if IS_ENABLED(CONFIG_USB_OMAP) omap_start_dma(int lch)467 void omap_start_dma(int lch) 468 { 469 u32 l; 470 471 /* 472 * The CPC/CDAC register needs to be initialized to zero 473 * before starting dma transfer. 474 */ 475 if (dma_omap15xx()) 476 p->dma_write(0, CPC, lch); 477 else 478 p->dma_write(0, CDAC, lch); 479 480 if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) { 481 int next_lch, cur_lch; 482 char dma_chan_link_map[MAX_LOGICAL_DMA_CH_COUNT]; 483 484 /* Set the link register of the first channel */ 485 enable_lnk(lch); 486 487 memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map)); 488 dma_chan_link_map[lch] = 1; 489 490 cur_lch = dma_chan[lch].next_lch; 491 do { 492 next_lch = dma_chan[cur_lch].next_lch; 493 494 /* The loop case: we've been here already */ 495 if (dma_chan_link_map[cur_lch]) 496 break; 497 /* Mark the current channel */ 498 dma_chan_link_map[cur_lch] = 1; 499 500 enable_lnk(cur_lch); 501 omap_enable_channel_irq(cur_lch); 502 503 cur_lch = next_lch; 504 } while (next_lch != -1); 505 } else if (IS_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS)) 506 p->dma_write(lch, CLNK_CTRL, lch); 507 508 omap_enable_channel_irq(lch); 509 510 l = p->dma_read(CCR, lch); 511 512 if (IS_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING)) 513 l |= OMAP_DMA_CCR_BUFFERING_DISABLE; 514 l |= OMAP_DMA_CCR_EN; 515 516 /* 517 * As dma_write() uses IO accessors which are weakly ordered, there 518 * is no guarantee that data in coherent DMA memory will be visible 519 * to the DMA device. Add a memory barrier here to ensure that any 520 * such data is visible prior to enabling DMA. 521 */ 522 mb(); 523 p->dma_write(l, CCR, lch); 524 525 dma_chan[lch].flags |= OMAP_DMA_ACTIVE; 526 } 527 EXPORT_SYMBOL(omap_start_dma); 528 omap_stop_dma(int lch)529 void omap_stop_dma(int lch) 530 { 531 u32 l; 532 533 /* Disable all interrupts on the channel */ 534 omap_disable_channel_irq(lch); 535 536 l = p->dma_read(CCR, lch); 537 if (IS_DMA_ERRATA(DMA_ERRATA_i541) && 538 (l & OMAP_DMA_CCR_SEL_SRC_DST_SYNC)) { 539 int i = 0; 540 u32 sys_cf; 541 542 /* Configure No-Standby */ 543 l = p->dma_read(OCP_SYSCONFIG, lch); 544 sys_cf = l; 545 l &= ~DMA_SYSCONFIG_MIDLEMODE_MASK; 546 l |= DMA_SYSCONFIG_MIDLEMODE(DMA_IDLEMODE_NO_IDLE); 547 p->dma_write(l , OCP_SYSCONFIG, 0); 548 549 l = p->dma_read(CCR, lch); 550 l &= ~OMAP_DMA_CCR_EN; 551 p->dma_write(l, CCR, lch); 552 553 /* Wait for sDMA FIFO drain */ 554 l = p->dma_read(CCR, lch); 555 while (i < 100 && (l & (OMAP_DMA_CCR_RD_ACTIVE | 556 OMAP_DMA_CCR_WR_ACTIVE))) { 557 udelay(5); 558 i++; 559 l = p->dma_read(CCR, lch); 560 } 561 if (i >= 100) 562 pr_err("DMA drain did not complete on lch %d\n", lch); 563 /* Restore OCP_SYSCONFIG */ 564 p->dma_write(sys_cf, OCP_SYSCONFIG, lch); 565 } else { 566 l &= ~OMAP_DMA_CCR_EN; 567 p->dma_write(l, CCR, lch); 568 } 569 570 /* 571 * Ensure that data transferred by DMA is visible to any access 572 * after DMA has been disabled. This is important for coherent 573 * DMA regions. 574 */ 575 mb(); 576 577 if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) { 578 int next_lch, cur_lch = lch; 579 char dma_chan_link_map[MAX_LOGICAL_DMA_CH_COUNT]; 580 581 memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map)); 582 do { 583 /* The loop case: we've been here already */ 584 if (dma_chan_link_map[cur_lch]) 585 break; 586 /* Mark the current channel */ 587 dma_chan_link_map[cur_lch] = 1; 588 589 disable_lnk(cur_lch); 590 591 next_lch = dma_chan[cur_lch].next_lch; 592 cur_lch = next_lch; 593 } while (next_lch != -1); 594 } 595 596 dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE; 597 } 598 EXPORT_SYMBOL(omap_stop_dma); 599 600 /* 601 * Allows changing the DMA callback function or data. This may be needed if 602 * the driver shares a single DMA channel for multiple dma triggers. 603 */ 604 /* 605 * Returns current physical source address for the given DMA channel. 606 * If the channel is running the caller must disable interrupts prior calling 607 * this function and process the returned value before re-enabling interrupt to 608 * prevent races with the interrupt handler. Note that in continuous mode there 609 * is a chance for CSSA_L register overflow between the two reads resulting 610 * in incorrect return value. 611 */ omap_get_dma_src_pos(int lch)612 dma_addr_t omap_get_dma_src_pos(int lch) 613 { 614 dma_addr_t offset = 0; 615 616 if (dma_omap15xx()) 617 offset = p->dma_read(CPC, lch); 618 else 619 offset = p->dma_read(CSAC, lch); 620 621 if (IS_DMA_ERRATA(DMA_ERRATA_3_3) && offset == 0) 622 offset = p->dma_read(CSAC, lch); 623 624 if (!dma_omap15xx()) { 625 /* 626 * CDAC == 0 indicates that the DMA transfer on the channel has 627 * not been started (no data has been transferred so far). 628 * Return the programmed source start address in this case. 629 */ 630 if (likely(p->dma_read(CDAC, lch))) 631 offset = p->dma_read(CSAC, lch); 632 else 633 offset = p->dma_read(CSSA, lch); 634 } 635 636 offset |= (p->dma_read(CSSA, lch) & 0xFFFF0000); 637 638 return offset; 639 } 640 EXPORT_SYMBOL(omap_get_dma_src_pos); 641 642 /* 643 * Returns current physical destination address for the given DMA channel. 644 * If the channel is running the caller must disable interrupts prior calling 645 * this function and process the returned value before re-enabling interrupt to 646 * prevent races with the interrupt handler. Note that in continuous mode there 647 * is a chance for CDSA_L register overflow between the two reads resulting 648 * in incorrect return value. 649 */ omap_get_dma_dst_pos(int lch)650 dma_addr_t omap_get_dma_dst_pos(int lch) 651 { 652 dma_addr_t offset = 0; 653 654 if (dma_omap15xx()) 655 offset = p->dma_read(CPC, lch); 656 else 657 offset = p->dma_read(CDAC, lch); 658 659 /* 660 * omap 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is 661 * read before the DMA controller finished disabling the channel. 662 */ 663 if (!dma_omap15xx() && offset == 0) { 664 offset = p->dma_read(CDAC, lch); 665 /* 666 * CDAC == 0 indicates that the DMA transfer on the channel has 667 * not been started (no data has been transferred so far). 668 * Return the programmed destination start address in this case. 669 */ 670 if (unlikely(!offset)) 671 offset = p->dma_read(CDSA, lch); 672 } 673 674 offset |= (p->dma_read(CDSA, lch) & 0xFFFF0000); 675 676 return offset; 677 } 678 EXPORT_SYMBOL(omap_get_dma_dst_pos); 679 omap_get_dma_active_status(int lch)680 int omap_get_dma_active_status(int lch) 681 { 682 return (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN) != 0; 683 } 684 EXPORT_SYMBOL(omap_get_dma_active_status); 685 #endif 686 omap_dma_running(void)687 int omap_dma_running(void) 688 { 689 int lch; 690 691 if (omap_lcd_dma_running()) 692 return 1; 693 694 for (lch = 0; lch < dma_chan_count; lch++) 695 if (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN) 696 return 1; 697 698 return 0; 699 } 700 701 /*----------------------------------------------------------------------------*/ 702 omap1_dma_handle_ch(int ch)703 static int omap1_dma_handle_ch(int ch) 704 { 705 u32 csr; 706 707 if (enable_1510_mode && ch >= 6) { 708 csr = dma_chan[ch].saved_csr; 709 dma_chan[ch].saved_csr = 0; 710 } else 711 csr = p->dma_read(CSR, ch); 712 if (enable_1510_mode && ch <= 2 && (csr >> 7) != 0) { 713 dma_chan[ch + 6].saved_csr = csr >> 7; 714 csr &= 0x7f; 715 } 716 if ((csr & 0x3f) == 0) 717 return 0; 718 if (unlikely(dma_chan[ch].dev_id == -1)) { 719 pr_warn("Spurious interrupt from DMA channel %d (CSR %04x)\n", 720 ch, csr); 721 return 0; 722 } 723 if (unlikely(csr & OMAP1_DMA_TOUT_IRQ)) 724 pr_warn("DMA timeout with device %d\n", dma_chan[ch].dev_id); 725 if (unlikely(csr & OMAP_DMA_DROP_IRQ)) 726 pr_warn("DMA synchronization event drop occurred with device %d\n", 727 dma_chan[ch].dev_id); 728 if (likely(csr & OMAP_DMA_BLOCK_IRQ)) 729 dma_chan[ch].flags &= ~OMAP_DMA_ACTIVE; 730 if (likely(dma_chan[ch].callback != NULL)) 731 dma_chan[ch].callback(ch, csr, dma_chan[ch].data); 732 733 return 1; 734 } 735 omap1_dma_irq_handler(int irq,void * dev_id)736 static irqreturn_t omap1_dma_irq_handler(int irq, void *dev_id) 737 { 738 int ch = ((int) dev_id) - 1; 739 int handled = 0; 740 741 for (;;) { 742 int handled_now = 0; 743 744 handled_now += omap1_dma_handle_ch(ch); 745 if (enable_1510_mode && dma_chan[ch + 6].saved_csr) 746 handled_now += omap1_dma_handle_ch(ch + 6); 747 if (!handled_now) 748 break; 749 handled += handled_now; 750 } 751 752 return handled ? IRQ_HANDLED : IRQ_NONE; 753 } 754 omap_get_plat_info(void)755 struct omap_system_dma_plat_info *omap_get_plat_info(void) 756 { 757 return p; 758 } 759 EXPORT_SYMBOL_GPL(omap_get_plat_info); 760 omap_system_dma_probe(struct platform_device * pdev)761 static int omap_system_dma_probe(struct platform_device *pdev) 762 { 763 int ch, ret = 0; 764 int dma_irq; 765 char irq_name[4]; 766 767 p = pdev->dev.platform_data; 768 if (!p) { 769 dev_err(&pdev->dev, 770 "%s: System DMA initialized without platform data\n", 771 __func__); 772 return -EINVAL; 773 } 774 775 d = p->dma_attr; 776 errata = p->errata; 777 778 if ((d->dev_caps & RESERVE_CHANNEL) && omap_dma_reserve_channels 779 && (omap_dma_reserve_channels < d->lch_count)) 780 d->lch_count = omap_dma_reserve_channels; 781 782 dma_lch_count = d->lch_count; 783 dma_chan_count = dma_lch_count; 784 enable_1510_mode = d->dev_caps & ENABLE_1510_MODE; 785 786 dma_chan = devm_kcalloc(&pdev->dev, dma_lch_count, 787 sizeof(*dma_chan), GFP_KERNEL); 788 if (!dma_chan) 789 return -ENOMEM; 790 791 for (ch = 0; ch < dma_chan_count; ch++) { 792 omap_clear_dma(ch); 793 794 dma_chan[ch].dev_id = -1; 795 dma_chan[ch].next_lch = -1; 796 797 if (ch >= 6 && enable_1510_mode) 798 continue; 799 800 /* 801 * request_irq() doesn't like dev_id (ie. ch) being 802 * zero, so we have to kludge around this. 803 */ 804 sprintf(&irq_name[0], "%d", ch); 805 dma_irq = platform_get_irq_byname(pdev, irq_name); 806 807 if (dma_irq < 0) { 808 ret = dma_irq; 809 goto exit_dma_irq_fail; 810 } 811 812 /* INT_DMA_LCD is handled in lcd_dma.c */ 813 if (dma_irq == INT_DMA_LCD) 814 continue; 815 816 ret = request_irq(dma_irq, 817 omap1_dma_irq_handler, 0, "DMA", 818 (void *) (ch + 1)); 819 if (ret != 0) 820 goto exit_dma_irq_fail; 821 } 822 823 /* reserve dma channels 0 and 1 in high security devices on 34xx */ 824 if (d->dev_caps & HS_CHANNELS_RESERVED) { 825 pr_info("Reserving DMA channels 0 and 1 for HS ROM code\n"); 826 dma_chan[0].dev_id = 0; 827 dma_chan[1].dev_id = 1; 828 } 829 p->show_dma_caps(); 830 return 0; 831 832 exit_dma_irq_fail: 833 return ret; 834 } 835 omap_system_dma_remove(struct platform_device * pdev)836 static void omap_system_dma_remove(struct platform_device *pdev) 837 { 838 int dma_irq, irq_rel = 0; 839 840 for ( ; irq_rel < dma_chan_count; irq_rel++) { 841 dma_irq = platform_get_irq(pdev, irq_rel); 842 free_irq(dma_irq, (void *)(irq_rel + 1)); 843 } 844 } 845 846 static struct platform_driver omap_system_dma_driver = { 847 .probe = omap_system_dma_probe, 848 .remove_new = omap_system_dma_remove, 849 .driver = { 850 .name = "omap_dma_system" 851 }, 852 }; 853 omap_system_dma_init(void)854 static int __init omap_system_dma_init(void) 855 { 856 return platform_driver_register(&omap_system_dma_driver); 857 } 858 arch_initcall(omap_system_dma_init); 859 omap_system_dma_exit(void)860 static void __exit omap_system_dma_exit(void) 861 { 862 platform_driver_unregister(&omap_system_dma_driver); 863 } 864 865 MODULE_DESCRIPTION("OMAP SYSTEM DMA DRIVER"); 866 MODULE_LICENSE("GPL"); 867 MODULE_AUTHOR("Texas Instruments Inc"); 868 869 /* 870 * Reserve the omap SDMA channels using cmdline bootarg 871 * "omap_dma_reserve_ch=". The valid range is 1 to 32 872 */ omap_dma_cmdline_reserve_ch(char * str)873 static int __init omap_dma_cmdline_reserve_ch(char *str) 874 { 875 if (get_option(&str, &omap_dma_reserve_channels) != 1) 876 omap_dma_reserve_channels = 0; 877 return 1; 878 } 879 880 __setup("omap_dma_reserve_ch=", omap_dma_cmdline_reserve_ch); 881 882 883