1// SPDX-License-Identifier: GPL-2.0 2/* 3 * Support for Macronix external hardware ECC engine for NAND devices, also 4 * called DPE for Data Processing Engine. 5 * 6 * Copyright �� 2019 Macronix 7 * Author: Miquel Raynal <miquel.raynal@bootlin.com> 8 */ 9 10#include <linux/dma-mapping.h> 11#include <linux/init.h> 12#include <linux/interrupt.h> 13#include <linux/io.h> 14#include <linux/iopoll.h> 15#include <linux/kernel.h> 16#include <linux/module.h> 17#include <linux/mtd/mtd.h> 18#include <linux/mtd/nand.h> 19#include <linux/mtd/nand-ecc-mxic.h> 20#include <linux/mutex.h> 21#include <linux/of.h> 22#include <linux/of_platform.h> 23#include <linux/platform_device.h> 24#include <linux/slab.h> 25 26/* DPE Configuration */ 27#define DP_CONFIG 0x00 28#define ECC_EN BIT(0) 29#define ECC_TYP(idx) (((idx) << 3) & GENMASK(6, 3)) 30/* DPE Interrupt Status */ 31#define INTRPT_STS 0x04 32#define TRANS_CMPLT BIT(0) 33#define SDMA_MAIN BIT(1) 34#define SDMA_SPARE BIT(2) 35#define ECC_ERR BIT(3) 36#define TO_SPARE BIT(4) 37#define TO_MAIN BIT(5) 38/* DPE Interrupt Status Enable */ 39#define INTRPT_STS_EN 0x08 40/* DPE Interrupt Signal Enable */ 41#define INTRPT_SIG_EN 0x0C 42/* Host Controller Configuration */ 43#define HC_CONFIG 0x10 44#define DEV2MEM 0 /* TRANS_TYP_DMA in the spec */ 45#define MEM2MEM BIT(4) /* TRANS_TYP_IO in the spec */ 46#define MAPPING BIT(5) /* TRANS_TYP_MAPPING in the spec */ 47#define ECC_PACKED 0 /* LAYOUT_TYP_INTEGRATED in the spec */ 48#define ECC_INTERLEAVED BIT(2) /* LAYOUT_TYP_DISTRIBUTED in the spec */ 49#define BURST_TYP_FIXED 0 50#define BURST_TYP_INCREASING BIT(0) 51/* Host Controller Slave Address */ 52#define HC_SLV_ADDR 0x14 53/* ECC Chunk Size */ 54#define CHUNK_SIZE 0x20 55/* Main Data Size */ 56#define MAIN_SIZE 0x24 57/* Spare Data Size */ 58#define SPARE_SIZE 0x28 59#define META_SZ(reg) ((reg) & GENMASK(7, 0)) 60#define PARITY_SZ(reg) (((reg) & GENMASK(15, 8)) >> 8) 61#define RSV_SZ(reg) (((reg) & GENMASK(23, 16)) >> 16) 62#define SPARE_SZ(reg) ((reg) >> 24) 63/* ECC Chunk Count */ 64#define CHUNK_CNT 0x30 65/* SDMA Control */ 66#define SDMA_CTRL 0x40 67#define WRITE_NAND 0 68#define READ_NAND BIT(1) 69#define CONT_NAND BIT(29) 70#define CONT_SYSM BIT(30) /* Continue System Memory? */ 71#define SDMA_STRT BIT(31) 72/* SDMA Address of Main Data */ 73#define SDMA_MAIN_ADDR 0x44 74/* SDMA Address of Spare Data */ 75#define SDMA_SPARE_ADDR 0x48 76/* DPE Version Number */ 77#define DP_VER 0xD0 78#define DP_VER_OFFSET 16 79 80/* Status bytes between each chunk of spare data */ 81#define STAT_BYTES 4 82#define NO_ERR 0x00 83#define MAX_CORR_ERR 0x28 84#define UNCORR_ERR 0xFE 85#define ERASED_CHUNK 0xFF 86 87struct mxic_ecc_engine { 88 struct device *dev; 89 void __iomem *regs; 90 int irq; 91 struct completion complete; 92 struct nand_ecc_engine external_engine; 93 struct nand_ecc_engine pipelined_engine; 94 struct mutex lock; 95}; 96 97struct mxic_ecc_ctx { 98 /* ECC machinery */ 99 unsigned int data_step_sz; 100 unsigned int oob_step_sz; 101 unsigned int parity_sz; 102 unsigned int meta_sz; 103 u8 *status; 104 int steps; 105 106 /* DMA boilerplate */ 107 struct nand_ecc_req_tweak_ctx req_ctx; 108 u8 *oobwithstat; 109 struct scatterlist sg[2]; 110 struct nand_page_io_req *req; 111 unsigned int pageoffs; 112}; 113 114static struct mxic_ecc_engine *ext_ecc_eng_to_mxic(struct nand_ecc_engine *eng) 115{ 116 return container_of(eng, struct mxic_ecc_engine, external_engine); 117} 118 119static struct mxic_ecc_engine *pip_ecc_eng_to_mxic(struct nand_ecc_engine *eng) 120{ 121 return container_of(eng, struct mxic_ecc_engine, pipelined_engine); 122} 123 124static struct mxic_ecc_engine *nand_to_mxic(struct nand_device *nand) 125{ 126 struct nand_ecc_engine *eng = nand->ecc.engine; 127 128 if (eng->integration == NAND_ECC_ENGINE_INTEGRATION_EXTERNAL) 129 return ext_ecc_eng_to_mxic(eng); 130 else 131 return pip_ecc_eng_to_mxic(eng); 132} 133 134static int mxic_ecc_ooblayout_ecc(struct mtd_info *mtd, int section, 135 struct mtd_oob_region *oobregion) 136{ 137 struct nand_device *nand = mtd_to_nanddev(mtd); 138 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 139 140 if (section < 0 || section >= ctx->steps) 141 return -ERANGE; 142 143 oobregion->offset = (section * ctx->oob_step_sz) + ctx->meta_sz; 144 oobregion->length = ctx->parity_sz; 145 146 return 0; 147} 148 149static int mxic_ecc_ooblayout_free(struct mtd_info *mtd, int section, 150 struct mtd_oob_region *oobregion) 151{ 152 struct nand_device *nand = mtd_to_nanddev(mtd); 153 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 154 155 if (section < 0 || section >= ctx->steps) 156 return -ERANGE; 157 158 if (!section) { 159 oobregion->offset = 2; 160 oobregion->length = ctx->meta_sz - 2; 161 } else { 162 oobregion->offset = section * ctx->oob_step_sz; 163 oobregion->length = ctx->meta_sz; 164 } 165 166 return 0; 167} 168 169static const struct mtd_ooblayout_ops mxic_ecc_ooblayout_ops = { 170 .ecc = mxic_ecc_ooblayout_ecc, 171 .free = mxic_ecc_ooblayout_free, 172}; 173 174static void mxic_ecc_disable_engine(struct mxic_ecc_engine *mxic) 175{ 176 u32 reg; 177 178 reg = readl(mxic->regs + DP_CONFIG); 179 reg &= ~ECC_EN; 180 writel(reg, mxic->regs + DP_CONFIG); 181} 182 183static void mxic_ecc_enable_engine(struct mxic_ecc_engine *mxic) 184{ 185 u32 reg; 186 187 reg = readl(mxic->regs + DP_CONFIG); 188 reg |= ECC_EN; 189 writel(reg, mxic->regs + DP_CONFIG); 190} 191 192static void mxic_ecc_disable_int(struct mxic_ecc_engine *mxic) 193{ 194 writel(0, mxic->regs + INTRPT_SIG_EN); 195} 196 197static void mxic_ecc_enable_int(struct mxic_ecc_engine *mxic) 198{ 199 writel(TRANS_CMPLT, mxic->regs + INTRPT_SIG_EN); 200} 201 202static irqreturn_t mxic_ecc_isr(int irq, void *dev_id) 203{ 204 struct mxic_ecc_engine *mxic = dev_id; 205 u32 sts; 206 207 sts = readl(mxic->regs + INTRPT_STS); 208 if (!sts) 209 return IRQ_NONE; 210 211 if (sts & TRANS_CMPLT) 212 complete(&mxic->complete); 213 214 writel(sts, mxic->regs + INTRPT_STS); 215 216 return IRQ_HANDLED; 217} 218 219static int mxic_ecc_init_ctx(struct nand_device *nand, struct device *dev) 220{ 221 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 222 struct nand_ecc_props *conf = &nand->ecc.ctx.conf; 223 struct nand_ecc_props *reqs = &nand->ecc.requirements; 224 struct nand_ecc_props *user = &nand->ecc.user_conf; 225 struct mtd_info *mtd = nanddev_to_mtd(nand); 226 int step_size = 0, strength = 0, desired_correction = 0, steps, idx; 227 static const int possible_strength[] = {4, 8, 40, 48}; 228 static const int spare_size[] = {32, 32, 96, 96}; 229 struct mxic_ecc_ctx *ctx; 230 u32 spare_reg; 231 int ret; 232 233 ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL); 234 if (!ctx) 235 return -ENOMEM; 236 237 nand->ecc.ctx.priv = ctx; 238 239 /* Only large page NAND chips may use BCH */ 240 if (mtd->oobsize < 64) { 241 pr_err("BCH cannot be used with small page NAND chips\n"); 242 return -EINVAL; 243 } 244 245 mtd_set_ooblayout(mtd, &mxic_ecc_ooblayout_ops); 246 247 /* Enable all status bits */ 248 writel(TRANS_CMPLT | SDMA_MAIN | SDMA_SPARE | ECC_ERR | 249 TO_SPARE | TO_MAIN, mxic->regs + INTRPT_STS_EN); 250 251 /* Configure the correction depending on the NAND device topology */ 252 if (user->step_size && user->strength) { 253 step_size = user->step_size; 254 strength = user->strength; 255 } else if (reqs->step_size && reqs->strength) { 256 step_size = reqs->step_size; 257 strength = reqs->strength; 258 } 259 260 if (step_size && strength) { 261 steps = mtd->writesize / step_size; 262 desired_correction = steps * strength; 263 } 264 265 /* Step size is fixed to 1kiB, strength may vary (4 possible values) */ 266 conf->step_size = SZ_1K; 267 steps = mtd->writesize / conf->step_size; 268 269 ctx->status = devm_kzalloc(dev, steps * sizeof(u8), GFP_KERNEL); 270 if (!ctx->status) 271 return -ENOMEM; 272 273 if (desired_correction) { 274 strength = desired_correction / steps; 275 276 for (idx = 0; idx < ARRAY_SIZE(possible_strength); idx++) 277 if (possible_strength[idx] >= strength) 278 break; 279 280 idx = min_t(unsigned int, idx, 281 ARRAY_SIZE(possible_strength) - 1); 282 } else { 283 /* Missing data, maximize the correction */ 284 idx = ARRAY_SIZE(possible_strength) - 1; 285 } 286 287 /* Tune the selected strength until it fits in the OOB area */ 288 for (; idx >= 0; idx--) { 289 if (spare_size[idx] * steps <= mtd->oobsize) 290 break; 291 } 292 293 /* This engine cannot be used with this NAND device */ 294 if (idx < 0) 295 return -EINVAL; 296 297 /* Configure the engine for the desired strength */ 298 writel(ECC_TYP(idx), mxic->regs + DP_CONFIG); 299 conf->strength = possible_strength[idx]; 300 spare_reg = readl(mxic->regs + SPARE_SIZE); 301 302 ctx->steps = steps; 303 ctx->data_step_sz = mtd->writesize / steps; 304 ctx->oob_step_sz = mtd->oobsize / steps; 305 ctx->parity_sz = PARITY_SZ(spare_reg); 306 ctx->meta_sz = META_SZ(spare_reg); 307 308 /* Ensure buffers will contain enough bytes to store the STAT_BYTES */ 309 ctx->req_ctx.oob_buffer_size = nanddev_per_page_oobsize(nand) + 310 (ctx->steps * STAT_BYTES); 311 ret = nand_ecc_init_req_tweaking(&ctx->req_ctx, nand); 312 if (ret) 313 return ret; 314 315 ctx->oobwithstat = kmalloc(mtd->oobsize + (ctx->steps * STAT_BYTES), 316 GFP_KERNEL); 317 if (!ctx->oobwithstat) { 318 ret = -ENOMEM; 319 goto cleanup_req_tweak; 320 } 321 322 sg_init_table(ctx->sg, 2); 323 324 /* Configuration dump and sanity checks */ 325 dev_err(dev, "DPE version number: %d\n", 326 readl(mxic->regs + DP_VER) >> DP_VER_OFFSET); 327 dev_err(dev, "Chunk size: %d\n", readl(mxic->regs + CHUNK_SIZE)); 328 dev_err(dev, "Main size: %d\n", readl(mxic->regs + MAIN_SIZE)); 329 dev_err(dev, "Spare size: %d\n", SPARE_SZ(spare_reg)); 330 dev_err(dev, "Rsv size: %ld\n", RSV_SZ(spare_reg)); 331 dev_err(dev, "Parity size: %d\n", ctx->parity_sz); 332 dev_err(dev, "Meta size: %d\n", ctx->meta_sz); 333 334 if ((ctx->meta_sz + ctx->parity_sz + RSV_SZ(spare_reg)) != 335 SPARE_SZ(spare_reg)) { 336 dev_err(dev, "Wrong OOB configuration: %d + %d + %ld != %d\n", 337 ctx->meta_sz, ctx->parity_sz, RSV_SZ(spare_reg), 338 SPARE_SZ(spare_reg)); 339 ret = -EINVAL; 340 goto free_oobwithstat; 341 } 342 343 if (ctx->oob_step_sz != SPARE_SZ(spare_reg)) { 344 dev_err(dev, "Wrong OOB configuration: %d != %d\n", 345 ctx->oob_step_sz, SPARE_SZ(spare_reg)); 346 ret = -EINVAL; 347 goto free_oobwithstat; 348 } 349 350 return 0; 351 352free_oobwithstat: 353 kfree(ctx->oobwithstat); 354cleanup_req_tweak: 355 nand_ecc_cleanup_req_tweaking(&ctx->req_ctx); 356 357 return ret; 358} 359 360static int mxic_ecc_init_ctx_external(struct nand_device *nand) 361{ 362 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 363 struct device *dev = nand->ecc.engine->dev; 364 int ret; 365 366 dev_info(dev, "Macronix ECC engine in external mode\n"); 367 368 ret = mxic_ecc_init_ctx(nand, dev); 369 if (ret) 370 return ret; 371 372 /* Trigger each step manually */ 373 writel(1, mxic->regs + CHUNK_CNT); 374 writel(BURST_TYP_INCREASING | ECC_PACKED | MEM2MEM, 375 mxic->regs + HC_CONFIG); 376 377 return 0; 378} 379 380static int mxic_ecc_init_ctx_pipelined(struct nand_device *nand) 381{ 382 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 383 struct mxic_ecc_ctx *ctx; 384 struct device *dev; 385 int ret; 386 387 dev = nand_ecc_get_engine_dev(nand->ecc.engine->dev); 388 if (!dev) 389 return -EINVAL; 390 391 dev_info(dev, "Macronix ECC engine in pipelined/mapping mode\n"); 392 393 ret = mxic_ecc_init_ctx(nand, dev); 394 if (ret) 395 return ret; 396 397 ctx = nand_to_ecc_ctx(nand); 398 399 /* All steps should be handled in one go directly by the internal DMA */ 400 writel(ctx->steps, mxic->regs + CHUNK_CNT); 401 402 /* 403 * Interleaved ECC scheme cannot be used otherwise factory bad block 404 * markers would be lost. A packed layout is mandatory. 405 */ 406 writel(BURST_TYP_INCREASING | ECC_PACKED | MAPPING, 407 mxic->regs + HC_CONFIG); 408 409 return 0; 410} 411 412static void mxic_ecc_cleanup_ctx(struct nand_device *nand) 413{ 414 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 415 416 if (ctx) { 417 nand_ecc_cleanup_req_tweaking(&ctx->req_ctx); 418 kfree(ctx->oobwithstat); 419 } 420} 421 422static int mxic_ecc_data_xfer_wait_for_completion(struct mxic_ecc_engine *mxic) 423{ 424 u32 val; 425 int ret; 426 427 if (mxic->irq) { 428 reinit_completion(&mxic->complete); 429 mxic_ecc_enable_int(mxic); 430 ret = wait_for_completion_timeout(&mxic->complete, 431 msecs_to_jiffies(1000)); 432 ret = ret ? 0 : -ETIMEDOUT; 433 mxic_ecc_disable_int(mxic); 434 } else { 435 ret = readl_poll_timeout(mxic->regs + INTRPT_STS, val, 436 val & TRANS_CMPLT, 10, USEC_PER_SEC); 437 writel(val, mxic->regs + INTRPT_STS); 438 } 439 440 if (ret) { 441 dev_err(mxic->dev, "Timeout on data xfer completion\n"); 442 return -ETIMEDOUT; 443 } 444 445 return 0; 446} 447 448static int mxic_ecc_process_data(struct mxic_ecc_engine *mxic, 449 unsigned int direction) 450{ 451 unsigned int dir = (direction == NAND_PAGE_READ) ? 452 READ_NAND : WRITE_NAND; 453 int ret; 454 455 mxic_ecc_enable_engine(mxic); 456 457 /* Trigger processing */ 458 writel(SDMA_STRT | dir, mxic->regs + SDMA_CTRL); 459 460 /* Wait for completion */ 461 ret = mxic_ecc_data_xfer_wait_for_completion(mxic); 462 463 mxic_ecc_disable_engine(mxic); 464 465 return ret; 466} 467 468int mxic_ecc_process_data_pipelined(struct nand_ecc_engine *eng, 469 unsigned int direction, dma_addr_t dirmap) 470{ 471 struct mxic_ecc_engine *mxic = pip_ecc_eng_to_mxic(eng); 472 473 if (dirmap) 474 writel(dirmap, mxic->regs + HC_SLV_ADDR); 475 476 return mxic_ecc_process_data(mxic, direction); 477} 478EXPORT_SYMBOL_GPL(mxic_ecc_process_data_pipelined); 479 480static void mxic_ecc_extract_status_bytes(struct mxic_ecc_ctx *ctx) 481{ 482 u8 *buf = ctx->oobwithstat; 483 int next_stat_pos; 484 int step; 485 486 /* Extract the ECC status */ 487 for (step = 0; step < ctx->steps; step++) { 488 next_stat_pos = ctx->oob_step_sz + 489 ((STAT_BYTES + ctx->oob_step_sz) * step); 490 491 ctx->status[step] = buf[next_stat_pos]; 492 } 493} 494 495static void mxic_ecc_reconstruct_oobbuf(struct mxic_ecc_ctx *ctx, 496 u8 *dst, const u8 *src) 497{ 498 int step; 499 500 /* Reconstruct the OOB buffer linearly (without the ECC status bytes) */ 501 for (step = 0; step < ctx->steps; step++) 502 memcpy(dst + (step * ctx->oob_step_sz), 503 src + (step * (ctx->oob_step_sz + STAT_BYTES)), 504 ctx->oob_step_sz); 505} 506 507static void mxic_ecc_add_room_in_oobbuf(struct mxic_ecc_ctx *ctx, 508 u8 *dst, const u8 *src) 509{ 510 int step; 511 512 /* Add some space in the OOB buffer for the status bytes */ 513 for (step = 0; step < ctx->steps; step++) 514 memcpy(dst + (step * (ctx->oob_step_sz + STAT_BYTES)), 515 src + (step * ctx->oob_step_sz), 516 ctx->oob_step_sz); 517} 518 519static int mxic_ecc_count_biterrs(struct mxic_ecc_engine *mxic, 520 struct nand_device *nand) 521{ 522 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 523 struct mtd_info *mtd = nanddev_to_mtd(nand); 524 struct device *dev = mxic->dev; 525 unsigned int max_bf = 0; 526 bool failure = false; 527 int step; 528 529 for (step = 0; step < ctx->steps; step++) { 530 u8 stat = ctx->status[step]; 531 532 if (stat == NO_ERR) { 533 dev_dbg(dev, "ECC step %d: no error\n", step); 534 } else if (stat == ERASED_CHUNK) { 535 dev_dbg(dev, "ECC step %d: erased\n", step); 536 } else if (stat == UNCORR_ERR || stat > MAX_CORR_ERR) { 537 dev_dbg(dev, "ECC step %d: uncorrectable\n", step); 538 mtd->ecc_stats.failed++; 539 failure = true; 540 } else { 541 dev_dbg(dev, "ECC step %d: %d bits corrected\n", 542 step, stat); 543 max_bf = max_t(unsigned int, max_bf, stat); 544 mtd->ecc_stats.corrected += stat; 545 } 546 } 547 548 return failure ? -EBADMSG : max_bf; 549} 550 551/* External ECC engine helpers */ 552static int mxic_ecc_prepare_io_req_external(struct nand_device *nand, 553 struct nand_page_io_req *req) 554{ 555 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 556 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 557 struct mtd_info *mtd = nanddev_to_mtd(nand); 558 int offset, nents, step, ret; 559 560 if (req->mode == MTD_OPS_RAW) 561 return 0; 562 563 nand_ecc_tweak_req(&ctx->req_ctx, req); 564 ctx->req = req; 565 566 if (req->type == NAND_PAGE_READ) 567 return 0; 568 569 mxic_ecc_add_room_in_oobbuf(ctx, ctx->oobwithstat, 570 ctx->req->oobbuf.out); 571 572 sg_set_buf(&ctx->sg[0], req->databuf.out, req->datalen); 573 sg_set_buf(&ctx->sg[1], ctx->oobwithstat, 574 req->ooblen + (ctx->steps * STAT_BYTES)); 575 576 nents = dma_map_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); 577 if (!nents) 578 return -EINVAL; 579 580 mutex_lock(&mxic->lock); 581 582 for (step = 0; step < ctx->steps; step++) { 583 writel(sg_dma_address(&ctx->sg[0]) + (step * ctx->data_step_sz), 584 mxic->regs + SDMA_MAIN_ADDR); 585 writel(sg_dma_address(&ctx->sg[1]) + (step * (ctx->oob_step_sz + STAT_BYTES)), 586 mxic->regs + SDMA_SPARE_ADDR); 587 ret = mxic_ecc_process_data(mxic, ctx->req->type); 588 if (ret) 589 break; 590 } 591 592 mutex_unlock(&mxic->lock); 593 594 dma_unmap_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); 595 596 if (ret) 597 return ret; 598 599 /* Retrieve the calculated ECC bytes */ 600 for (step = 0; step < ctx->steps; step++) { 601 offset = ctx->meta_sz + (step * ctx->oob_step_sz); 602 mtd_ooblayout_get_eccbytes(mtd, 603 (u8 *)ctx->req->oobbuf.out + offset, 604 ctx->oobwithstat + (step * STAT_BYTES), 605 step * ctx->parity_sz, 606 ctx->parity_sz); 607 } 608 609 return 0; 610} 611 612static int mxic_ecc_finish_io_req_external(struct nand_device *nand, 613 struct nand_page_io_req *req) 614{ 615 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 616 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 617 int nents, step, ret; 618 619 if (req->mode == MTD_OPS_RAW) 620 return 0; 621 622 if (req->type == NAND_PAGE_WRITE) { 623 nand_ecc_restore_req(&ctx->req_ctx, req); 624 return 0; 625 } 626 627 /* Copy the OOB buffer and add room for the ECC engine status bytes */ 628 mxic_ecc_add_room_in_oobbuf(ctx, ctx->oobwithstat, ctx->req->oobbuf.in); 629 630 sg_set_buf(&ctx->sg[0], req->databuf.in, req->datalen); 631 sg_set_buf(&ctx->sg[1], ctx->oobwithstat, 632 req->ooblen + (ctx->steps * STAT_BYTES)); 633 nents = dma_map_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); 634 if (!nents) 635 return -EINVAL; 636 637 mutex_lock(&mxic->lock); 638 639 for (step = 0; step < ctx->steps; step++) { 640 writel(sg_dma_address(&ctx->sg[0]) + (step * ctx->data_step_sz), 641 mxic->regs + SDMA_MAIN_ADDR); 642 writel(sg_dma_address(&ctx->sg[1]) + (step * (ctx->oob_step_sz + STAT_BYTES)), 643 mxic->regs + SDMA_SPARE_ADDR); 644 ret = mxic_ecc_process_data(mxic, ctx->req->type); 645 if (ret) 646 break; 647 } 648 649 mutex_unlock(&mxic->lock); 650 651 dma_unmap_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); 652 653 if (ret) { 654 nand_ecc_restore_req(&ctx->req_ctx, req); 655 return ret; 656 } 657 658 /* Extract the status bytes and reconstruct the buffer */ 659 mxic_ecc_extract_status_bytes(ctx); 660 mxic_ecc_reconstruct_oobbuf(ctx, ctx->req->oobbuf.in, ctx->oobwithstat); 661 662 nand_ecc_restore_req(&ctx->req_ctx, req); 663 664 return mxic_ecc_count_biterrs(mxic, nand); 665} 666 667/* Pipelined ECC engine helpers */ 668static int mxic_ecc_prepare_io_req_pipelined(struct nand_device *nand, 669 struct nand_page_io_req *req) 670{ 671 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 672 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 673 int nents; 674 675 if (req->mode == MTD_OPS_RAW) 676 return 0; 677 678 nand_ecc_tweak_req(&ctx->req_ctx, req); 679 ctx->req = req; 680 681 /* Copy the OOB buffer and add room for the ECC engine status bytes */ 682 mxic_ecc_add_room_in_oobbuf(ctx, ctx->oobwithstat, ctx->req->oobbuf.in); 683 684 sg_set_buf(&ctx->sg[0], req->databuf.in, req->datalen); 685 sg_set_buf(&ctx->sg[1], ctx->oobwithstat, 686 req->ooblen + (ctx->steps * STAT_BYTES)); 687 688 nents = dma_map_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); 689 if (!nents) 690 return -EINVAL; 691 692 mutex_lock(&mxic->lock); 693 694 writel(sg_dma_address(&ctx->sg[0]), mxic->regs + SDMA_MAIN_ADDR); 695 writel(sg_dma_address(&ctx->sg[1]), mxic->regs + SDMA_SPARE_ADDR); 696 697 return 0; 698} 699 700static int mxic_ecc_finish_io_req_pipelined(struct nand_device *nand, 701 struct nand_page_io_req *req) 702{ 703 struct mxic_ecc_engine *mxic = nand_to_mxic(nand); 704 struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); 705 int ret = 0; 706 707 if (req->mode == MTD_OPS_RAW) 708 return 0; 709 710 mutex_unlock(&mxic->lock); 711 712 dma_unmap_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); 713 714 if (req->type == NAND_PAGE_READ) { 715 mxic_ecc_extract_status_bytes(ctx); 716 mxic_ecc_reconstruct_oobbuf(ctx, ctx->req->oobbuf.in, 717 ctx->oobwithstat); 718 ret = mxic_ecc_count_biterrs(mxic, nand); 719 } 720 721 nand_ecc_restore_req(&ctx->req_ctx, req); 722 723 return ret; 724} 725 726static struct nand_ecc_engine_ops mxic_ecc_engine_external_ops = { 727 .init_ctx = mxic_ecc_init_ctx_external, 728 .cleanup_ctx = mxic_ecc_cleanup_ctx, 729 .prepare_io_req = mxic_ecc_prepare_io_req_external, 730 .finish_io_req = mxic_ecc_finish_io_req_external, 731}; 732 733static struct nand_ecc_engine_ops mxic_ecc_engine_pipelined_ops = { 734 .init_ctx = mxic_ecc_init_ctx_pipelined, 735 .cleanup_ctx = mxic_ecc_cleanup_ctx, 736 .prepare_io_req = mxic_ecc_prepare_io_req_pipelined, 737 .finish_io_req = mxic_ecc_finish_io_req_pipelined, 738}; 739 740struct nand_ecc_engine_ops *mxic_ecc_get_pipelined_ops(void) 741{ 742 return &mxic_ecc_engine_pipelined_ops; 743} 744EXPORT_SYMBOL_GPL(mxic_ecc_get_pipelined_ops); 745 746static struct platform_device * 747mxic_ecc_get_pdev(struct platform_device *spi_pdev) 748{ 749 struct platform_device *eng_pdev; 750 struct device_node *np; 751 752 /* Retrieve the nand-ecc-engine phandle */ 753 np = of_parse_phandle(spi_pdev->dev.of_node, "nand-ecc-engine", 0); 754 if (!np) 755 return NULL; 756 757 /* Jump to the engine's device node */ 758 eng_pdev = of_find_device_by_node(np); 759 of_node_put(np); 760 761 return eng_pdev; 762} 763 764void mxic_ecc_put_pipelined_engine(struct nand_ecc_engine *eng) 765{ 766 struct mxic_ecc_engine *mxic = pip_ecc_eng_to_mxic(eng); 767 768 platform_device_put(to_platform_device(mxic->dev)); 769} 770EXPORT_SYMBOL_GPL(mxic_ecc_put_pipelined_engine); 771 772struct nand_ecc_engine * 773mxic_ecc_get_pipelined_engine(struct platform_device *spi_pdev) 774{ 775 struct platform_device *eng_pdev; 776 struct mxic_ecc_engine *mxic; 777 778 eng_pdev = mxic_ecc_get_pdev(spi_pdev); 779 if (!eng_pdev) 780 return ERR_PTR(-ENODEV); 781 782 mxic = platform_get_drvdata(eng_pdev); 783 if (!mxic) { 784 platform_device_put(eng_pdev); 785 return ERR_PTR(-EPROBE_DEFER); 786 } 787 788 return &mxic->pipelined_engine; 789} 790EXPORT_SYMBOL_GPL(mxic_ecc_get_pipelined_engine); 791 792/* 793 * Only the external ECC engine is exported as the pipelined is SoC specific, so 794 * it is registered directly by the drivers that wrap it. 795 */ 796static int mxic_ecc_probe(struct platform_device *pdev) 797{ 798 struct device *dev = &pdev->dev; 799 struct mxic_ecc_engine *mxic; 800 int ret; 801 802 mxic = devm_kzalloc(&pdev->dev, sizeof(*mxic), GFP_KERNEL); 803 if (!mxic) 804 return -ENOMEM; 805 806 mxic->dev = &pdev->dev; 807 808 /* 809 * Both memory regions for the ECC engine itself and the AXI slave 810 * address are mandatory. 811 */ 812 mxic->regs = devm_platform_ioremap_resource(pdev, 0); 813 if (IS_ERR(mxic->regs)) { 814 dev_err(&pdev->dev, "Missing memory region\n"); 815 return PTR_ERR(mxic->regs); 816 } 817 818 mxic_ecc_disable_engine(mxic); 819 mxic_ecc_disable_int(mxic); 820 821 /* IRQ is optional yet much more efficient */ 822 mxic->irq = platform_get_irq_byname_optional(pdev, "ecc-engine"); 823 if (mxic->irq > 0) { 824 ret = devm_request_irq(&pdev->dev, mxic->irq, mxic_ecc_isr, 0, 825 "mxic-ecc", mxic); 826 if (ret) 827 return ret; 828 } else { 829 dev_info(dev, "Invalid or missing IRQ, fallback to polling\n"); 830 mxic->irq = 0; 831 } 832 833 mutex_init(&mxic->lock); 834 835 /* 836 * In external mode, the device is the ECC engine. In pipelined mode, 837 * the device is the host controller. The device is used to match the 838 * right ECC engine based on the DT properties. 839 */ 840 mxic->external_engine.dev = &pdev->dev; 841 mxic->external_engine.integration = NAND_ECC_ENGINE_INTEGRATION_EXTERNAL; 842 mxic->external_engine.ops = &mxic_ecc_engine_external_ops; 843 844 nand_ecc_register_on_host_hw_engine(&mxic->external_engine); 845 846 platform_set_drvdata(pdev, mxic); 847 848 return 0; 849} 850 851static void mxic_ecc_remove(struct platform_device *pdev) 852{ 853 struct mxic_ecc_engine *mxic = platform_get_drvdata(pdev); 854 855 nand_ecc_unregister_on_host_hw_engine(&mxic->external_engine); 856} 857 858static const struct of_device_id mxic_ecc_of_ids[] = { 859 { 860 .compatible = "mxicy,nand-ecc-engine-rev3", 861 }, 862 { /* sentinel */ }, 863}; 864MODULE_DEVICE_TABLE(of, mxic_ecc_of_ids); 865 866static struct platform_driver mxic_ecc_driver = { 867 .driver = { 868 .name = "mxic-nand-ecc-engine", 869 .of_match_table = mxic_ecc_of_ids, 870 }, 871 .probe = mxic_ecc_probe, 872 .remove_new = mxic_ecc_remove, 873}; 874module_platform_driver(mxic_ecc_driver); 875 876MODULE_LICENSE("GPL"); 877MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>"); 878MODULE_DESCRIPTION("Macronix NAND hardware ECC controller"); 879