1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * SPI driver for NVIDIA's Tegra114 SPI Controller. 4 * 5 * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved. 6 */ 7 8 #include <linux/clk.h> 9 #include <linux/completion.h> 10 #include <linux/delay.h> 11 #include <linux/dmaengine.h> 12 #include <linux/dma-mapping.h> 13 #include <linux/dmapool.h> 14 #include <linux/err.h> 15 #include <linux/interrupt.h> 16 #include <linux/io.h> 17 #include <linux/kernel.h> 18 #include <linux/kthread.h> 19 #include <linux/module.h> 20 #include <linux/platform_device.h> 21 #include <linux/pm_runtime.h> 22 #include <linux/of.h> 23 #include <linux/of_device.h> 24 #include <linux/reset.h> 25 #include <linux/spi/spi.h> 26 27 #define SPI_COMMAND1 0x000 28 #define SPI_BIT_LENGTH(x) (((x) & 0x1f) << 0) 29 #define SPI_PACKED (1 << 5) 30 #define SPI_TX_EN (1 << 11) 31 #define SPI_RX_EN (1 << 12) 32 #define SPI_BOTH_EN_BYTE (1 << 13) 33 #define SPI_BOTH_EN_BIT (1 << 14) 34 #define SPI_LSBYTE_FE (1 << 15) 35 #define SPI_LSBIT_FE (1 << 16) 36 #define SPI_BIDIROE (1 << 17) 37 #define SPI_IDLE_SDA_DRIVE_LOW (0 << 18) 38 #define SPI_IDLE_SDA_DRIVE_HIGH (1 << 18) 39 #define SPI_IDLE_SDA_PULL_LOW (2 << 18) 40 #define SPI_IDLE_SDA_PULL_HIGH (3 << 18) 41 #define SPI_IDLE_SDA_MASK (3 << 18) 42 #define SPI_CS_SW_VAL (1 << 20) 43 #define SPI_CS_SW_HW (1 << 21) 44 /* SPI_CS_POL_INACTIVE bits are default high */ 45 /* n from 0 to 3 */ 46 #define SPI_CS_POL_INACTIVE(n) (1 << (22 + (n))) 47 #define SPI_CS_POL_INACTIVE_MASK (0xF << 22) 48 49 #define SPI_CS_SEL_0 (0 << 26) 50 #define SPI_CS_SEL_1 (1 << 26) 51 #define SPI_CS_SEL_2 (2 << 26) 52 #define SPI_CS_SEL_3 (3 << 26) 53 #define SPI_CS_SEL_MASK (3 << 26) 54 #define SPI_CS_SEL(x) (((x) & 0x3) << 26) 55 #define SPI_CONTROL_MODE_0 (0 << 28) 56 #define SPI_CONTROL_MODE_1 (1 << 28) 57 #define SPI_CONTROL_MODE_2 (2 << 28) 58 #define SPI_CONTROL_MODE_3 (3 << 28) 59 #define SPI_CONTROL_MODE_MASK (3 << 28) 60 #define SPI_MODE_SEL(x) (((x) & 0x3) << 28) 61 #define SPI_M_S (1 << 30) 62 #define SPI_PIO (1 << 31) 63 64 #define SPI_COMMAND2 0x004 65 #define SPI_TX_TAP_DELAY(x) (((x) & 0x3F) << 6) 66 #define SPI_RX_TAP_DELAY(x) (((x) & 0x3F) << 0) 67 68 #define SPI_CS_TIMING1 0x008 69 #define SPI_SETUP_HOLD(setup, hold) (((setup) << 4) | (hold)) 70 #define SPI_CS_SETUP_HOLD(reg, cs, val) \ 71 ((((val) & 0xFFu) << ((cs) * 8)) | \ 72 ((reg) & ~(0xFFu << ((cs) * 8)))) 73 74 #define SPI_CS_TIMING2 0x00C 75 #define CYCLES_BETWEEN_PACKETS_0(x) (((x) & 0x1F) << 0) 76 #define CS_ACTIVE_BETWEEN_PACKETS_0 (1 << 5) 77 #define CYCLES_BETWEEN_PACKETS_1(x) (((x) & 0x1F) << 8) 78 #define CS_ACTIVE_BETWEEN_PACKETS_1 (1 << 13) 79 #define CYCLES_BETWEEN_PACKETS_2(x) (((x) & 0x1F) << 16) 80 #define CS_ACTIVE_BETWEEN_PACKETS_2 (1 << 21) 81 #define CYCLES_BETWEEN_PACKETS_3(x) (((x) & 0x1F) << 24) 82 #define CS_ACTIVE_BETWEEN_PACKETS_3 (1 << 29) 83 #define SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(reg, cs, val) \ 84 (reg = (((val) & 0x1) << ((cs) * 8 + 5)) | \ 85 ((reg) & ~(1 << ((cs) * 8 + 5)))) 86 #define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val) \ 87 (reg = (((val) & 0x1F) << ((cs) * 8)) | \ 88 ((reg) & ~(0x1F << ((cs) * 8)))) 89 #define MAX_SETUP_HOLD_CYCLES 16 90 #define MAX_INACTIVE_CYCLES 32 91 92 #define SPI_TRANS_STATUS 0x010 93 #define SPI_BLK_CNT(val) (((val) >> 0) & 0xFFFF) 94 #define SPI_SLV_IDLE_COUNT(val) (((val) >> 16) & 0xFF) 95 #define SPI_RDY (1 << 30) 96 97 #define SPI_FIFO_STATUS 0x014 98 #define SPI_RX_FIFO_EMPTY (1 << 0) 99 #define SPI_RX_FIFO_FULL (1 << 1) 100 #define SPI_TX_FIFO_EMPTY (1 << 2) 101 #define SPI_TX_FIFO_FULL (1 << 3) 102 #define SPI_RX_FIFO_UNF (1 << 4) 103 #define SPI_RX_FIFO_OVF (1 << 5) 104 #define SPI_TX_FIFO_UNF (1 << 6) 105 #define SPI_TX_FIFO_OVF (1 << 7) 106 #define SPI_ERR (1 << 8) 107 #define SPI_TX_FIFO_FLUSH (1 << 14) 108 #define SPI_RX_FIFO_FLUSH (1 << 15) 109 #define SPI_TX_FIFO_EMPTY_COUNT(val) (((val) >> 16) & 0x7F) 110 #define SPI_RX_FIFO_FULL_COUNT(val) (((val) >> 23) & 0x7F) 111 #define SPI_FRAME_END (1 << 30) 112 #define SPI_CS_INACTIVE (1 << 31) 113 114 #define SPI_FIFO_ERROR (SPI_RX_FIFO_UNF | \ 115 SPI_RX_FIFO_OVF | SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF) 116 #define SPI_FIFO_EMPTY (SPI_RX_FIFO_EMPTY | SPI_TX_FIFO_EMPTY) 117 118 #define SPI_TX_DATA 0x018 119 #define SPI_RX_DATA 0x01C 120 121 #define SPI_DMA_CTL 0x020 122 #define SPI_TX_TRIG_1 (0 << 15) 123 #define SPI_TX_TRIG_4 (1 << 15) 124 #define SPI_TX_TRIG_8 (2 << 15) 125 #define SPI_TX_TRIG_16 (3 << 15) 126 #define SPI_TX_TRIG_MASK (3 << 15) 127 #define SPI_RX_TRIG_1 (0 << 19) 128 #define SPI_RX_TRIG_4 (1 << 19) 129 #define SPI_RX_TRIG_8 (2 << 19) 130 #define SPI_RX_TRIG_16 (3 << 19) 131 #define SPI_RX_TRIG_MASK (3 << 19) 132 #define SPI_IE_TX (1 << 28) 133 #define SPI_IE_RX (1 << 29) 134 #define SPI_CONT (1 << 30) 135 #define SPI_DMA (1 << 31) 136 #define SPI_DMA_EN SPI_DMA 137 138 #define SPI_DMA_BLK 0x024 139 #define SPI_DMA_BLK_SET(x) (((x) & 0xFFFF) << 0) 140 141 #define SPI_TX_FIFO 0x108 142 #define SPI_RX_FIFO 0x188 143 #define SPI_INTR_MASK 0x18c 144 #define SPI_INTR_ALL_MASK (0x1fUL << 25) 145 #define MAX_CHIP_SELECT 4 146 #define SPI_FIFO_DEPTH 64 147 #define DATA_DIR_TX (1 << 0) 148 #define DATA_DIR_RX (1 << 1) 149 150 #define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) 151 #define DEFAULT_SPI_DMA_BUF_LEN (16*1024) 152 #define TX_FIFO_EMPTY_COUNT_MAX SPI_TX_FIFO_EMPTY_COUNT(0x40) 153 #define RX_FIFO_FULL_COUNT_ZERO SPI_RX_FIFO_FULL_COUNT(0) 154 #define MAX_HOLD_CYCLES 16 155 #define SPI_DEFAULT_SPEED 25000000 156 157 struct tegra_spi_soc_data { 158 bool has_intr_mask_reg; 159 }; 160 161 struct tegra_spi_client_data { 162 int tx_clk_tap_delay; 163 int rx_clk_tap_delay; 164 }; 165 166 struct tegra_spi_data { 167 struct device *dev; 168 struct spi_master *master; 169 spinlock_t lock; 170 171 struct clk *clk; 172 struct reset_control *rst; 173 void __iomem *base; 174 phys_addr_t phys; 175 unsigned irq; 176 u32 cur_speed; 177 178 struct spi_device *cur_spi; 179 struct spi_device *cs_control; 180 unsigned cur_pos; 181 unsigned words_per_32bit; 182 unsigned bytes_per_word; 183 unsigned curr_dma_words; 184 unsigned cur_direction; 185 186 unsigned cur_rx_pos; 187 unsigned cur_tx_pos; 188 189 unsigned dma_buf_size; 190 unsigned max_buf_size; 191 bool is_curr_dma_xfer; 192 bool use_hw_based_cs; 193 194 struct completion rx_dma_complete; 195 struct completion tx_dma_complete; 196 197 u32 tx_status; 198 u32 rx_status; 199 u32 status_reg; 200 bool is_packed; 201 202 u32 command1_reg; 203 u32 dma_control_reg; 204 u32 def_command1_reg; 205 u32 def_command2_reg; 206 u32 spi_cs_timing1; 207 u32 spi_cs_timing2; 208 u8 last_used_cs; 209 210 struct completion xfer_completion; 211 struct spi_transfer *curr_xfer; 212 struct dma_chan *rx_dma_chan; 213 u32 *rx_dma_buf; 214 dma_addr_t rx_dma_phys; 215 struct dma_async_tx_descriptor *rx_dma_desc; 216 217 struct dma_chan *tx_dma_chan; 218 u32 *tx_dma_buf; 219 dma_addr_t tx_dma_phys; 220 struct dma_async_tx_descriptor *tx_dma_desc; 221 const struct tegra_spi_soc_data *soc_data; 222 }; 223 224 static int tegra_spi_runtime_suspend(struct device *dev); 225 static int tegra_spi_runtime_resume(struct device *dev); 226 227 static inline u32 tegra_spi_readl(struct tegra_spi_data *tspi, 228 unsigned long reg) 229 { 230 return readl(tspi->base + reg); 231 } 232 233 static inline void tegra_spi_writel(struct tegra_spi_data *tspi, 234 u32 val, unsigned long reg) 235 { 236 writel(val, tspi->base + reg); 237 238 /* Read back register to make sure that register writes completed */ 239 if (reg != SPI_TX_FIFO) 240 readl(tspi->base + SPI_COMMAND1); 241 } 242 243 static void tegra_spi_clear_status(struct tegra_spi_data *tspi) 244 { 245 u32 val; 246 247 /* Write 1 to clear status register */ 248 val = tegra_spi_readl(tspi, SPI_TRANS_STATUS); 249 tegra_spi_writel(tspi, val, SPI_TRANS_STATUS); 250 251 /* Clear fifo status error if any */ 252 val = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 253 if (val & SPI_ERR) 254 tegra_spi_writel(tspi, SPI_ERR | SPI_FIFO_ERROR, 255 SPI_FIFO_STATUS); 256 } 257 258 static unsigned tegra_spi_calculate_curr_xfer_param( 259 struct spi_device *spi, struct tegra_spi_data *tspi, 260 struct spi_transfer *t) 261 { 262 unsigned remain_len = t->len - tspi->cur_pos; 263 unsigned max_word; 264 unsigned bits_per_word = t->bits_per_word; 265 unsigned max_len; 266 unsigned total_fifo_words; 267 268 tspi->bytes_per_word = DIV_ROUND_UP(bits_per_word, 8); 269 270 if ((bits_per_word == 8 || bits_per_word == 16 || 271 bits_per_word == 32) && t->len > 3) { 272 tspi->is_packed = true; 273 tspi->words_per_32bit = 32/bits_per_word; 274 } else { 275 tspi->is_packed = false; 276 tspi->words_per_32bit = 1; 277 } 278 279 if (tspi->is_packed) { 280 max_len = min(remain_len, tspi->max_buf_size); 281 tspi->curr_dma_words = max_len/tspi->bytes_per_word; 282 total_fifo_words = (max_len + 3) / 4; 283 } else { 284 max_word = (remain_len - 1) / tspi->bytes_per_word + 1; 285 max_word = min(max_word, tspi->max_buf_size/4); 286 tspi->curr_dma_words = max_word; 287 total_fifo_words = max_word; 288 } 289 return total_fifo_words; 290 } 291 292 static unsigned tegra_spi_fill_tx_fifo_from_client_txbuf( 293 struct tegra_spi_data *tspi, struct spi_transfer *t) 294 { 295 unsigned nbytes; 296 unsigned tx_empty_count; 297 u32 fifo_status; 298 unsigned max_n_32bit; 299 unsigned i, count; 300 unsigned int written_words; 301 unsigned fifo_words_left; 302 u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; 303 304 fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 305 tx_empty_count = SPI_TX_FIFO_EMPTY_COUNT(fifo_status); 306 307 if (tspi->is_packed) { 308 fifo_words_left = tx_empty_count * tspi->words_per_32bit; 309 written_words = min(fifo_words_left, tspi->curr_dma_words); 310 nbytes = written_words * tspi->bytes_per_word; 311 max_n_32bit = DIV_ROUND_UP(nbytes, 4); 312 for (count = 0; count < max_n_32bit; count++) { 313 u32 x = 0; 314 315 for (i = 0; (i < 4) && nbytes; i++, nbytes--) 316 x |= (u32)(*tx_buf++) << (i * 8); 317 tegra_spi_writel(tspi, x, SPI_TX_FIFO); 318 } 319 320 tspi->cur_tx_pos += written_words * tspi->bytes_per_word; 321 } else { 322 unsigned int write_bytes; 323 max_n_32bit = min(tspi->curr_dma_words, tx_empty_count); 324 written_words = max_n_32bit; 325 nbytes = written_words * tspi->bytes_per_word; 326 if (nbytes > t->len - tspi->cur_pos) 327 nbytes = t->len - tspi->cur_pos; 328 write_bytes = nbytes; 329 for (count = 0; count < max_n_32bit; count++) { 330 u32 x = 0; 331 332 for (i = 0; nbytes && (i < tspi->bytes_per_word); 333 i++, nbytes--) 334 x |= (u32)(*tx_buf++) << (i * 8); 335 tegra_spi_writel(tspi, x, SPI_TX_FIFO); 336 } 337 338 tspi->cur_tx_pos += write_bytes; 339 } 340 341 return written_words; 342 } 343 344 static unsigned int tegra_spi_read_rx_fifo_to_client_rxbuf( 345 struct tegra_spi_data *tspi, struct spi_transfer *t) 346 { 347 unsigned rx_full_count; 348 u32 fifo_status; 349 unsigned i, count; 350 unsigned int read_words = 0; 351 unsigned len; 352 u8 *rx_buf = (u8 *)t->rx_buf + tspi->cur_rx_pos; 353 354 fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 355 rx_full_count = SPI_RX_FIFO_FULL_COUNT(fifo_status); 356 if (tspi->is_packed) { 357 len = tspi->curr_dma_words * tspi->bytes_per_word; 358 for (count = 0; count < rx_full_count; count++) { 359 u32 x = tegra_spi_readl(tspi, SPI_RX_FIFO); 360 361 for (i = 0; len && (i < 4); i++, len--) 362 *rx_buf++ = (x >> i*8) & 0xFF; 363 } 364 read_words += tspi->curr_dma_words; 365 tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; 366 } else { 367 u32 rx_mask = ((u32)1 << t->bits_per_word) - 1; 368 u8 bytes_per_word = tspi->bytes_per_word; 369 unsigned int read_bytes; 370 371 len = rx_full_count * bytes_per_word; 372 if (len > t->len - tspi->cur_pos) 373 len = t->len - tspi->cur_pos; 374 read_bytes = len; 375 for (count = 0; count < rx_full_count; count++) { 376 u32 x = tegra_spi_readl(tspi, SPI_RX_FIFO) & rx_mask; 377 378 for (i = 0; len && (i < bytes_per_word); i++, len--) 379 *rx_buf++ = (x >> (i*8)) & 0xFF; 380 } 381 read_words += rx_full_count; 382 tspi->cur_rx_pos += read_bytes; 383 } 384 385 return read_words; 386 } 387 388 static void tegra_spi_copy_client_txbuf_to_spi_txbuf( 389 struct tegra_spi_data *tspi, struct spi_transfer *t) 390 { 391 /* Make the dma buffer to read by cpu */ 392 dma_sync_single_for_cpu(tspi->dev, tspi->tx_dma_phys, 393 tspi->dma_buf_size, DMA_TO_DEVICE); 394 395 if (tspi->is_packed) { 396 unsigned len = tspi->curr_dma_words * tspi->bytes_per_word; 397 398 memcpy(tspi->tx_dma_buf, t->tx_buf + tspi->cur_pos, len); 399 tspi->cur_tx_pos += tspi->curr_dma_words * tspi->bytes_per_word; 400 } else { 401 unsigned int i; 402 unsigned int count; 403 u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos; 404 unsigned consume = tspi->curr_dma_words * tspi->bytes_per_word; 405 unsigned int write_bytes; 406 407 if (consume > t->len - tspi->cur_pos) 408 consume = t->len - tspi->cur_pos; 409 write_bytes = consume; 410 for (count = 0; count < tspi->curr_dma_words; count++) { 411 u32 x = 0; 412 413 for (i = 0; consume && (i < tspi->bytes_per_word); 414 i++, consume--) 415 x |= (u32)(*tx_buf++) << (i * 8); 416 tspi->tx_dma_buf[count] = x; 417 } 418 419 tspi->cur_tx_pos += write_bytes; 420 } 421 422 /* Make the dma buffer to read by dma */ 423 dma_sync_single_for_device(tspi->dev, tspi->tx_dma_phys, 424 tspi->dma_buf_size, DMA_TO_DEVICE); 425 } 426 427 static void tegra_spi_copy_spi_rxbuf_to_client_rxbuf( 428 struct tegra_spi_data *tspi, struct spi_transfer *t) 429 { 430 /* Make the dma buffer to read by cpu */ 431 dma_sync_single_for_cpu(tspi->dev, tspi->rx_dma_phys, 432 tspi->dma_buf_size, DMA_FROM_DEVICE); 433 434 if (tspi->is_packed) { 435 unsigned len = tspi->curr_dma_words * tspi->bytes_per_word; 436 437 memcpy(t->rx_buf + tspi->cur_rx_pos, tspi->rx_dma_buf, len); 438 tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word; 439 } else { 440 unsigned int i; 441 unsigned int count; 442 unsigned char *rx_buf = t->rx_buf + tspi->cur_rx_pos; 443 u32 rx_mask = ((u32)1 << t->bits_per_word) - 1; 444 unsigned consume = tspi->curr_dma_words * tspi->bytes_per_word; 445 unsigned int read_bytes; 446 447 if (consume > t->len - tspi->cur_pos) 448 consume = t->len - tspi->cur_pos; 449 read_bytes = consume; 450 for (count = 0; count < tspi->curr_dma_words; count++) { 451 u32 x = tspi->rx_dma_buf[count] & rx_mask; 452 453 for (i = 0; consume && (i < tspi->bytes_per_word); 454 i++, consume--) 455 *rx_buf++ = (x >> (i*8)) & 0xFF; 456 } 457 458 tspi->cur_rx_pos += read_bytes; 459 } 460 461 /* Make the dma buffer to read by dma */ 462 dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, 463 tspi->dma_buf_size, DMA_FROM_DEVICE); 464 } 465 466 static void tegra_spi_dma_complete(void *args) 467 { 468 struct completion *dma_complete = args; 469 470 complete(dma_complete); 471 } 472 473 static int tegra_spi_start_tx_dma(struct tegra_spi_data *tspi, int len) 474 { 475 reinit_completion(&tspi->tx_dma_complete); 476 tspi->tx_dma_desc = dmaengine_prep_slave_single(tspi->tx_dma_chan, 477 tspi->tx_dma_phys, len, DMA_MEM_TO_DEV, 478 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 479 if (!tspi->tx_dma_desc) { 480 dev_err(tspi->dev, "Not able to get desc for Tx\n"); 481 return -EIO; 482 } 483 484 tspi->tx_dma_desc->callback = tegra_spi_dma_complete; 485 tspi->tx_dma_desc->callback_param = &tspi->tx_dma_complete; 486 487 dmaengine_submit(tspi->tx_dma_desc); 488 dma_async_issue_pending(tspi->tx_dma_chan); 489 return 0; 490 } 491 492 static int tegra_spi_start_rx_dma(struct tegra_spi_data *tspi, int len) 493 { 494 reinit_completion(&tspi->rx_dma_complete); 495 tspi->rx_dma_desc = dmaengine_prep_slave_single(tspi->rx_dma_chan, 496 tspi->rx_dma_phys, len, DMA_DEV_TO_MEM, 497 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 498 if (!tspi->rx_dma_desc) { 499 dev_err(tspi->dev, "Not able to get desc for Rx\n"); 500 return -EIO; 501 } 502 503 tspi->rx_dma_desc->callback = tegra_spi_dma_complete; 504 tspi->rx_dma_desc->callback_param = &tspi->rx_dma_complete; 505 506 dmaengine_submit(tspi->rx_dma_desc); 507 dma_async_issue_pending(tspi->rx_dma_chan); 508 return 0; 509 } 510 511 static int tegra_spi_flush_fifos(struct tegra_spi_data *tspi) 512 { 513 unsigned long timeout = jiffies + HZ; 514 u32 status; 515 516 status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 517 if ((status & SPI_FIFO_EMPTY) != SPI_FIFO_EMPTY) { 518 status |= SPI_RX_FIFO_FLUSH | SPI_TX_FIFO_FLUSH; 519 tegra_spi_writel(tspi, status, SPI_FIFO_STATUS); 520 while ((status & SPI_FIFO_EMPTY) != SPI_FIFO_EMPTY) { 521 status = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 522 if (time_after(jiffies, timeout)) { 523 dev_err(tspi->dev, 524 "timeout waiting for fifo flush\n"); 525 return -EIO; 526 } 527 528 udelay(1); 529 } 530 } 531 532 return 0; 533 } 534 535 static int tegra_spi_start_dma_based_transfer( 536 struct tegra_spi_data *tspi, struct spi_transfer *t) 537 { 538 u32 val; 539 unsigned int len; 540 int ret = 0; 541 u8 dma_burst; 542 struct dma_slave_config dma_sconfig = {0}; 543 544 val = SPI_DMA_BLK_SET(tspi->curr_dma_words - 1); 545 tegra_spi_writel(tspi, val, SPI_DMA_BLK); 546 547 if (tspi->is_packed) 548 len = DIV_ROUND_UP(tspi->curr_dma_words * tspi->bytes_per_word, 549 4) * 4; 550 else 551 len = tspi->curr_dma_words * 4; 552 553 /* Set attention level based on length of transfer */ 554 if (len & 0xF) { 555 val |= SPI_TX_TRIG_1 | SPI_RX_TRIG_1; 556 dma_burst = 1; 557 } else if (((len) >> 4) & 0x1) { 558 val |= SPI_TX_TRIG_4 | SPI_RX_TRIG_4; 559 dma_burst = 4; 560 } else { 561 val |= SPI_TX_TRIG_8 | SPI_RX_TRIG_8; 562 dma_burst = 8; 563 } 564 565 if (!tspi->soc_data->has_intr_mask_reg) { 566 if (tspi->cur_direction & DATA_DIR_TX) 567 val |= SPI_IE_TX; 568 569 if (tspi->cur_direction & DATA_DIR_RX) 570 val |= SPI_IE_RX; 571 } 572 573 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 574 tspi->dma_control_reg = val; 575 576 dma_sconfig.device_fc = true; 577 if (tspi->cur_direction & DATA_DIR_TX) { 578 dma_sconfig.dst_addr = tspi->phys + SPI_TX_FIFO; 579 dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 580 dma_sconfig.dst_maxburst = dma_burst; 581 ret = dmaengine_slave_config(tspi->tx_dma_chan, &dma_sconfig); 582 if (ret < 0) { 583 dev_err(tspi->dev, 584 "DMA slave config failed: %d\n", ret); 585 return ret; 586 } 587 588 tegra_spi_copy_client_txbuf_to_spi_txbuf(tspi, t); 589 ret = tegra_spi_start_tx_dma(tspi, len); 590 if (ret < 0) { 591 dev_err(tspi->dev, 592 "Starting tx dma failed, err %d\n", ret); 593 return ret; 594 } 595 } 596 597 if (tspi->cur_direction & DATA_DIR_RX) { 598 dma_sconfig.src_addr = tspi->phys + SPI_RX_FIFO; 599 dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 600 dma_sconfig.src_maxburst = dma_burst; 601 ret = dmaengine_slave_config(tspi->rx_dma_chan, &dma_sconfig); 602 if (ret < 0) { 603 dev_err(tspi->dev, 604 "DMA slave config failed: %d\n", ret); 605 return ret; 606 } 607 608 /* Make the dma buffer to read by dma */ 609 dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys, 610 tspi->dma_buf_size, DMA_FROM_DEVICE); 611 612 ret = tegra_spi_start_rx_dma(tspi, len); 613 if (ret < 0) { 614 dev_err(tspi->dev, 615 "Starting rx dma failed, err %d\n", ret); 616 if (tspi->cur_direction & DATA_DIR_TX) 617 dmaengine_terminate_all(tspi->tx_dma_chan); 618 return ret; 619 } 620 } 621 tspi->is_curr_dma_xfer = true; 622 tspi->dma_control_reg = val; 623 624 val |= SPI_DMA_EN; 625 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 626 return ret; 627 } 628 629 static int tegra_spi_start_cpu_based_transfer( 630 struct tegra_spi_data *tspi, struct spi_transfer *t) 631 { 632 u32 val; 633 unsigned cur_words; 634 635 if (tspi->cur_direction & DATA_DIR_TX) 636 cur_words = tegra_spi_fill_tx_fifo_from_client_txbuf(tspi, t); 637 else 638 cur_words = tspi->curr_dma_words; 639 640 val = SPI_DMA_BLK_SET(cur_words - 1); 641 tegra_spi_writel(tspi, val, SPI_DMA_BLK); 642 643 val = 0; 644 if (tspi->cur_direction & DATA_DIR_TX) 645 val |= SPI_IE_TX; 646 647 if (tspi->cur_direction & DATA_DIR_RX) 648 val |= SPI_IE_RX; 649 650 tegra_spi_writel(tspi, val, SPI_DMA_CTL); 651 tspi->dma_control_reg = val; 652 653 tspi->is_curr_dma_xfer = false; 654 655 val = tspi->command1_reg; 656 val |= SPI_PIO; 657 tegra_spi_writel(tspi, val, SPI_COMMAND1); 658 return 0; 659 } 660 661 static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi, 662 bool dma_to_memory) 663 { 664 struct dma_chan *dma_chan; 665 u32 *dma_buf; 666 dma_addr_t dma_phys; 667 668 dma_chan = dma_request_chan(tspi->dev, dma_to_memory ? "rx" : "tx"); 669 if (IS_ERR(dma_chan)) 670 return dev_err_probe(tspi->dev, PTR_ERR(dma_chan), 671 "Dma channel is not available\n"); 672 673 dma_buf = dma_alloc_coherent(tspi->dev, tspi->dma_buf_size, 674 &dma_phys, GFP_KERNEL); 675 if (!dma_buf) { 676 dev_err(tspi->dev, " Not able to allocate the dma buffer\n"); 677 dma_release_channel(dma_chan); 678 return -ENOMEM; 679 } 680 681 if (dma_to_memory) { 682 tspi->rx_dma_chan = dma_chan; 683 tspi->rx_dma_buf = dma_buf; 684 tspi->rx_dma_phys = dma_phys; 685 } else { 686 tspi->tx_dma_chan = dma_chan; 687 tspi->tx_dma_buf = dma_buf; 688 tspi->tx_dma_phys = dma_phys; 689 } 690 return 0; 691 } 692 693 static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, 694 bool dma_to_memory) 695 { 696 u32 *dma_buf; 697 dma_addr_t dma_phys; 698 struct dma_chan *dma_chan; 699 700 if (dma_to_memory) { 701 dma_buf = tspi->rx_dma_buf; 702 dma_chan = tspi->rx_dma_chan; 703 dma_phys = tspi->rx_dma_phys; 704 tspi->rx_dma_chan = NULL; 705 tspi->rx_dma_buf = NULL; 706 } else { 707 dma_buf = tspi->tx_dma_buf; 708 dma_chan = tspi->tx_dma_chan; 709 dma_phys = tspi->tx_dma_phys; 710 tspi->tx_dma_buf = NULL; 711 tspi->tx_dma_chan = NULL; 712 } 713 if (!dma_chan) 714 return; 715 716 dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); 717 dma_release_channel(dma_chan); 718 } 719 720 static int tegra_spi_set_hw_cs_timing(struct spi_device *spi) 721 { 722 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 723 struct spi_delay *setup = &spi->cs_setup; 724 struct spi_delay *hold = &spi->cs_hold; 725 struct spi_delay *inactive = &spi->cs_inactive; 726 u8 setup_dly, hold_dly, inactive_dly; 727 u32 setup_hold; 728 u32 spi_cs_timing; 729 u32 inactive_cycles; 730 u8 cs_state; 731 732 if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) || 733 (hold && hold->unit != SPI_DELAY_UNIT_SCK) || 734 (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) { 735 dev_err(&spi->dev, 736 "Invalid delay unit %d, should be SPI_DELAY_UNIT_SCK\n", 737 SPI_DELAY_UNIT_SCK); 738 return -EINVAL; 739 } 740 741 setup_dly = setup ? setup->value : 0; 742 hold_dly = hold ? hold->value : 0; 743 inactive_dly = inactive ? inactive->value : 0; 744 745 setup_dly = min_t(u8, setup_dly, MAX_SETUP_HOLD_CYCLES); 746 hold_dly = min_t(u8, hold_dly, MAX_SETUP_HOLD_CYCLES); 747 if (setup_dly && hold_dly) { 748 setup_hold = SPI_SETUP_HOLD(setup_dly - 1, hold_dly - 1); 749 spi_cs_timing = SPI_CS_SETUP_HOLD(tspi->spi_cs_timing1, 750 spi->chip_select, 751 setup_hold); 752 if (tspi->spi_cs_timing1 != spi_cs_timing) { 753 tspi->spi_cs_timing1 = spi_cs_timing; 754 tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING1); 755 } 756 } 757 758 inactive_cycles = min_t(u8, inactive_dly, MAX_INACTIVE_CYCLES); 759 if (inactive_cycles) 760 inactive_cycles--; 761 cs_state = inactive_cycles ? 0 : 1; 762 spi_cs_timing = tspi->spi_cs_timing2; 763 SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select, 764 cs_state); 765 SPI_SET_CYCLES_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select, 766 inactive_cycles); 767 if (tspi->spi_cs_timing2 != spi_cs_timing) { 768 tspi->spi_cs_timing2 = spi_cs_timing; 769 tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING2); 770 } 771 772 return 0; 773 } 774 775 static u32 tegra_spi_setup_transfer_one(struct spi_device *spi, 776 struct spi_transfer *t, 777 bool is_first_of_msg, 778 bool is_single_xfer) 779 { 780 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 781 struct tegra_spi_client_data *cdata = spi->controller_data; 782 u32 speed = t->speed_hz; 783 u8 bits_per_word = t->bits_per_word; 784 u32 command1, command2; 785 int req_mode; 786 u32 tx_tap = 0, rx_tap = 0; 787 788 if (speed != tspi->cur_speed) { 789 clk_set_rate(tspi->clk, speed); 790 tspi->cur_speed = speed; 791 } 792 793 tspi->cur_spi = spi; 794 tspi->cur_pos = 0; 795 tspi->cur_rx_pos = 0; 796 tspi->cur_tx_pos = 0; 797 tspi->curr_xfer = t; 798 799 if (is_first_of_msg) { 800 tegra_spi_clear_status(tspi); 801 802 command1 = tspi->def_command1_reg; 803 command1 |= SPI_BIT_LENGTH(bits_per_word - 1); 804 805 command1 &= ~SPI_CONTROL_MODE_MASK; 806 req_mode = spi->mode & 0x3; 807 if (req_mode == SPI_MODE_0) 808 command1 |= SPI_CONTROL_MODE_0; 809 else if (req_mode == SPI_MODE_1) 810 command1 |= SPI_CONTROL_MODE_1; 811 else if (req_mode == SPI_MODE_2) 812 command1 |= SPI_CONTROL_MODE_2; 813 else if (req_mode == SPI_MODE_3) 814 command1 |= SPI_CONTROL_MODE_3; 815 816 if (spi->mode & SPI_LSB_FIRST) 817 command1 |= SPI_LSBIT_FE; 818 else 819 command1 &= ~SPI_LSBIT_FE; 820 821 if (spi->mode & SPI_3WIRE) 822 command1 |= SPI_BIDIROE; 823 else 824 command1 &= ~SPI_BIDIROE; 825 826 if (tspi->cs_control) { 827 if (tspi->cs_control != spi) 828 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 829 tspi->cs_control = NULL; 830 } else 831 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 832 833 /* GPIO based chip select control */ 834 if (spi->cs_gpiod) 835 gpiod_set_value(spi->cs_gpiod, 1); 836 837 if (is_single_xfer && !(t->cs_change)) { 838 tspi->use_hw_based_cs = true; 839 command1 &= ~(SPI_CS_SW_HW | SPI_CS_SW_VAL); 840 } else { 841 tspi->use_hw_based_cs = false; 842 command1 |= SPI_CS_SW_HW; 843 if (spi->mode & SPI_CS_HIGH) 844 command1 |= SPI_CS_SW_VAL; 845 else 846 command1 &= ~SPI_CS_SW_VAL; 847 } 848 849 if (tspi->last_used_cs != spi->chip_select) { 850 if (cdata && cdata->tx_clk_tap_delay) 851 tx_tap = cdata->tx_clk_tap_delay; 852 if (cdata && cdata->rx_clk_tap_delay) 853 rx_tap = cdata->rx_clk_tap_delay; 854 command2 = SPI_TX_TAP_DELAY(tx_tap) | 855 SPI_RX_TAP_DELAY(rx_tap); 856 if (command2 != tspi->def_command2_reg) 857 tegra_spi_writel(tspi, command2, SPI_COMMAND2); 858 tspi->last_used_cs = spi->chip_select; 859 } 860 861 } else { 862 command1 = tspi->command1_reg; 863 command1 &= ~SPI_BIT_LENGTH(~0); 864 command1 |= SPI_BIT_LENGTH(bits_per_word - 1); 865 } 866 867 return command1; 868 } 869 870 static int tegra_spi_start_transfer_one(struct spi_device *spi, 871 struct spi_transfer *t, u32 command1) 872 { 873 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 874 unsigned total_fifo_words; 875 int ret; 876 877 total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t); 878 879 if (t->rx_nbits == SPI_NBITS_DUAL || t->tx_nbits == SPI_NBITS_DUAL) 880 command1 |= SPI_BOTH_EN_BIT; 881 else 882 command1 &= ~SPI_BOTH_EN_BIT; 883 884 if (tspi->is_packed) 885 command1 |= SPI_PACKED; 886 else 887 command1 &= ~SPI_PACKED; 888 889 command1 &= ~(SPI_CS_SEL_MASK | SPI_TX_EN | SPI_RX_EN); 890 tspi->cur_direction = 0; 891 if (t->rx_buf) { 892 command1 |= SPI_RX_EN; 893 tspi->cur_direction |= DATA_DIR_RX; 894 } 895 if (t->tx_buf) { 896 command1 |= SPI_TX_EN; 897 tspi->cur_direction |= DATA_DIR_TX; 898 } 899 command1 |= SPI_CS_SEL(spi->chip_select); 900 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 901 tspi->command1_reg = command1; 902 903 dev_dbg(tspi->dev, "The def 0x%x and written 0x%x\n", 904 tspi->def_command1_reg, (unsigned)command1); 905 906 ret = tegra_spi_flush_fifos(tspi); 907 if (ret < 0) 908 return ret; 909 if (total_fifo_words > SPI_FIFO_DEPTH) 910 ret = tegra_spi_start_dma_based_transfer(tspi, t); 911 else 912 ret = tegra_spi_start_cpu_based_transfer(tspi, t); 913 return ret; 914 } 915 916 static struct tegra_spi_client_data 917 *tegra_spi_parse_cdata_dt(struct spi_device *spi) 918 { 919 struct tegra_spi_client_data *cdata; 920 struct device_node *slave_np; 921 922 slave_np = spi->dev.of_node; 923 if (!slave_np) { 924 dev_dbg(&spi->dev, "device node not found\n"); 925 return NULL; 926 } 927 928 cdata = kzalloc(sizeof(*cdata), GFP_KERNEL); 929 if (!cdata) 930 return NULL; 931 932 of_property_read_u32(slave_np, "nvidia,tx-clk-tap-delay", 933 &cdata->tx_clk_tap_delay); 934 of_property_read_u32(slave_np, "nvidia,rx-clk-tap-delay", 935 &cdata->rx_clk_tap_delay); 936 return cdata; 937 } 938 939 static void tegra_spi_cleanup(struct spi_device *spi) 940 { 941 struct tegra_spi_client_data *cdata = spi->controller_data; 942 943 spi->controller_data = NULL; 944 if (spi->dev.of_node) 945 kfree(cdata); 946 } 947 948 static int tegra_spi_setup(struct spi_device *spi) 949 { 950 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 951 struct tegra_spi_client_data *cdata = spi->controller_data; 952 u32 val; 953 unsigned long flags; 954 int ret; 955 956 dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n", 957 spi->bits_per_word, 958 spi->mode & SPI_CPOL ? "" : "~", 959 spi->mode & SPI_CPHA ? "" : "~", 960 spi->max_speed_hz); 961 962 if (!cdata) { 963 cdata = tegra_spi_parse_cdata_dt(spi); 964 spi->controller_data = cdata; 965 } 966 967 ret = pm_runtime_get_sync(tspi->dev); 968 if (ret < 0) { 969 pm_runtime_put_noidle(tspi->dev); 970 dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret); 971 if (cdata) 972 tegra_spi_cleanup(spi); 973 return ret; 974 } 975 976 if (tspi->soc_data->has_intr_mask_reg) { 977 val = tegra_spi_readl(tspi, SPI_INTR_MASK); 978 val &= ~SPI_INTR_ALL_MASK; 979 tegra_spi_writel(tspi, val, SPI_INTR_MASK); 980 } 981 982 spin_lock_irqsave(&tspi->lock, flags); 983 /* GPIO based chip select control */ 984 if (spi->cs_gpiod) 985 gpiod_set_value(spi->cs_gpiod, 0); 986 987 val = tspi->def_command1_reg; 988 if (spi->mode & SPI_CS_HIGH) 989 val &= ~SPI_CS_POL_INACTIVE(spi->chip_select); 990 else 991 val |= SPI_CS_POL_INACTIVE(spi->chip_select); 992 tspi->def_command1_reg = val; 993 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 994 spin_unlock_irqrestore(&tspi->lock, flags); 995 996 pm_runtime_put(tspi->dev); 997 return 0; 998 } 999 1000 static void tegra_spi_transfer_end(struct spi_device *spi) 1001 { 1002 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 1003 int cs_val = (spi->mode & SPI_CS_HIGH) ? 0 : 1; 1004 1005 /* GPIO based chip select control */ 1006 if (spi->cs_gpiod) 1007 gpiod_set_value(spi->cs_gpiod, 0); 1008 1009 if (!tspi->use_hw_based_cs) { 1010 if (cs_val) 1011 tspi->command1_reg |= SPI_CS_SW_VAL; 1012 else 1013 tspi->command1_reg &= ~SPI_CS_SW_VAL; 1014 tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); 1015 } 1016 1017 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 1018 } 1019 1020 static void tegra_spi_dump_regs(struct tegra_spi_data *tspi) 1021 { 1022 dev_dbg(tspi->dev, "============ SPI REGISTER DUMP ============\n"); 1023 dev_dbg(tspi->dev, "Command1: 0x%08x | Command2: 0x%08x\n", 1024 tegra_spi_readl(tspi, SPI_COMMAND1), 1025 tegra_spi_readl(tspi, SPI_COMMAND2)); 1026 dev_dbg(tspi->dev, "DMA_CTL: 0x%08x | DMA_BLK: 0x%08x\n", 1027 tegra_spi_readl(tspi, SPI_DMA_CTL), 1028 tegra_spi_readl(tspi, SPI_DMA_BLK)); 1029 dev_dbg(tspi->dev, "TRANS_STAT: 0x%08x | FIFO_STATUS: 0x%08x\n", 1030 tegra_spi_readl(tspi, SPI_TRANS_STATUS), 1031 tegra_spi_readl(tspi, SPI_FIFO_STATUS)); 1032 } 1033 1034 static int tegra_spi_transfer_one_message(struct spi_master *master, 1035 struct spi_message *msg) 1036 { 1037 bool is_first_msg = true; 1038 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1039 struct spi_transfer *xfer; 1040 struct spi_device *spi = msg->spi; 1041 int ret; 1042 bool skip = false; 1043 int single_xfer; 1044 1045 msg->status = 0; 1046 msg->actual_length = 0; 1047 1048 single_xfer = list_is_singular(&msg->transfers); 1049 list_for_each_entry(xfer, &msg->transfers, transfer_list) { 1050 u32 cmd1; 1051 1052 reinit_completion(&tspi->xfer_completion); 1053 1054 cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg, 1055 single_xfer); 1056 1057 if (!xfer->len) { 1058 ret = 0; 1059 skip = true; 1060 goto complete_xfer; 1061 } 1062 1063 ret = tegra_spi_start_transfer_one(spi, xfer, cmd1); 1064 if (ret < 0) { 1065 dev_err(tspi->dev, 1066 "spi can not start transfer, err %d\n", ret); 1067 goto complete_xfer; 1068 } 1069 1070 is_first_msg = false; 1071 ret = wait_for_completion_timeout(&tspi->xfer_completion, 1072 SPI_DMA_TIMEOUT); 1073 if (WARN_ON(ret == 0)) { 1074 dev_err(tspi->dev, "spi transfer timeout\n"); 1075 if (tspi->is_curr_dma_xfer && 1076 (tspi->cur_direction & DATA_DIR_TX)) 1077 dmaengine_terminate_all(tspi->tx_dma_chan); 1078 if (tspi->is_curr_dma_xfer && 1079 (tspi->cur_direction & DATA_DIR_RX)) 1080 dmaengine_terminate_all(tspi->rx_dma_chan); 1081 ret = -EIO; 1082 tegra_spi_dump_regs(tspi); 1083 tegra_spi_flush_fifos(tspi); 1084 reset_control_assert(tspi->rst); 1085 udelay(2); 1086 reset_control_deassert(tspi->rst); 1087 tspi->last_used_cs = master->num_chipselect + 1; 1088 goto complete_xfer; 1089 } 1090 1091 if (tspi->tx_status || tspi->rx_status) { 1092 dev_err(tspi->dev, "Error in Transfer\n"); 1093 ret = -EIO; 1094 tegra_spi_dump_regs(tspi); 1095 goto complete_xfer; 1096 } 1097 msg->actual_length += xfer->len; 1098 1099 complete_xfer: 1100 if (ret < 0 || skip) { 1101 tegra_spi_transfer_end(spi); 1102 spi_transfer_delay_exec(xfer); 1103 goto exit; 1104 } else if (list_is_last(&xfer->transfer_list, 1105 &msg->transfers)) { 1106 if (xfer->cs_change) 1107 tspi->cs_control = spi; 1108 else { 1109 tegra_spi_transfer_end(spi); 1110 spi_transfer_delay_exec(xfer); 1111 } 1112 } else if (xfer->cs_change) { 1113 tegra_spi_transfer_end(spi); 1114 spi_transfer_delay_exec(xfer); 1115 } 1116 1117 } 1118 ret = 0; 1119 exit: 1120 msg->status = ret; 1121 spi_finalize_current_message(master); 1122 return ret; 1123 } 1124 1125 static irqreturn_t handle_cpu_based_xfer(struct tegra_spi_data *tspi) 1126 { 1127 struct spi_transfer *t = tspi->curr_xfer; 1128 unsigned long flags; 1129 1130 spin_lock_irqsave(&tspi->lock, flags); 1131 if (tspi->tx_status || tspi->rx_status) { 1132 dev_err(tspi->dev, "CpuXfer ERROR bit set 0x%x\n", 1133 tspi->status_reg); 1134 dev_err(tspi->dev, "CpuXfer 0x%08x:0x%08x\n", 1135 tspi->command1_reg, tspi->dma_control_reg); 1136 tegra_spi_dump_regs(tspi); 1137 tegra_spi_flush_fifos(tspi); 1138 complete(&tspi->xfer_completion); 1139 spin_unlock_irqrestore(&tspi->lock, flags); 1140 reset_control_assert(tspi->rst); 1141 udelay(2); 1142 reset_control_deassert(tspi->rst); 1143 return IRQ_HANDLED; 1144 } 1145 1146 if (tspi->cur_direction & DATA_DIR_RX) 1147 tegra_spi_read_rx_fifo_to_client_rxbuf(tspi, t); 1148 1149 if (tspi->cur_direction & DATA_DIR_TX) 1150 tspi->cur_pos = tspi->cur_tx_pos; 1151 else 1152 tspi->cur_pos = tspi->cur_rx_pos; 1153 1154 if (tspi->cur_pos == t->len) { 1155 complete(&tspi->xfer_completion); 1156 goto exit; 1157 } 1158 1159 tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, tspi, t); 1160 tegra_spi_start_cpu_based_transfer(tspi, t); 1161 exit: 1162 spin_unlock_irqrestore(&tspi->lock, flags); 1163 return IRQ_HANDLED; 1164 } 1165 1166 static irqreturn_t handle_dma_based_xfer(struct tegra_spi_data *tspi) 1167 { 1168 struct spi_transfer *t = tspi->curr_xfer; 1169 long wait_status; 1170 int err = 0; 1171 unsigned total_fifo_words; 1172 unsigned long flags; 1173 1174 /* Abort dmas if any error */ 1175 if (tspi->cur_direction & DATA_DIR_TX) { 1176 if (tspi->tx_status) { 1177 dmaengine_terminate_all(tspi->tx_dma_chan); 1178 err += 1; 1179 } else { 1180 wait_status = wait_for_completion_interruptible_timeout( 1181 &tspi->tx_dma_complete, SPI_DMA_TIMEOUT); 1182 if (wait_status <= 0) { 1183 dmaengine_terminate_all(tspi->tx_dma_chan); 1184 dev_err(tspi->dev, "TxDma Xfer failed\n"); 1185 err += 1; 1186 } 1187 } 1188 } 1189 1190 if (tspi->cur_direction & DATA_DIR_RX) { 1191 if (tspi->rx_status) { 1192 dmaengine_terminate_all(tspi->rx_dma_chan); 1193 err += 2; 1194 } else { 1195 wait_status = wait_for_completion_interruptible_timeout( 1196 &tspi->rx_dma_complete, SPI_DMA_TIMEOUT); 1197 if (wait_status <= 0) { 1198 dmaengine_terminate_all(tspi->rx_dma_chan); 1199 dev_err(tspi->dev, "RxDma Xfer failed\n"); 1200 err += 2; 1201 } 1202 } 1203 } 1204 1205 spin_lock_irqsave(&tspi->lock, flags); 1206 if (err) { 1207 dev_err(tspi->dev, "DmaXfer: ERROR bit set 0x%x\n", 1208 tspi->status_reg); 1209 dev_err(tspi->dev, "DmaXfer 0x%08x:0x%08x\n", 1210 tspi->command1_reg, tspi->dma_control_reg); 1211 tegra_spi_dump_regs(tspi); 1212 tegra_spi_flush_fifos(tspi); 1213 complete(&tspi->xfer_completion); 1214 spin_unlock_irqrestore(&tspi->lock, flags); 1215 reset_control_assert(tspi->rst); 1216 udelay(2); 1217 reset_control_deassert(tspi->rst); 1218 return IRQ_HANDLED; 1219 } 1220 1221 if (tspi->cur_direction & DATA_DIR_RX) 1222 tegra_spi_copy_spi_rxbuf_to_client_rxbuf(tspi, t); 1223 1224 if (tspi->cur_direction & DATA_DIR_TX) 1225 tspi->cur_pos = tspi->cur_tx_pos; 1226 else 1227 tspi->cur_pos = tspi->cur_rx_pos; 1228 1229 if (tspi->cur_pos == t->len) { 1230 complete(&tspi->xfer_completion); 1231 goto exit; 1232 } 1233 1234 /* Continue transfer in current message */ 1235 total_fifo_words = tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, 1236 tspi, t); 1237 if (total_fifo_words > SPI_FIFO_DEPTH) 1238 err = tegra_spi_start_dma_based_transfer(tspi, t); 1239 else 1240 err = tegra_spi_start_cpu_based_transfer(tspi, t); 1241 1242 exit: 1243 spin_unlock_irqrestore(&tspi->lock, flags); 1244 return IRQ_HANDLED; 1245 } 1246 1247 static irqreturn_t tegra_spi_isr_thread(int irq, void *context_data) 1248 { 1249 struct tegra_spi_data *tspi = context_data; 1250 1251 if (!tspi->is_curr_dma_xfer) 1252 return handle_cpu_based_xfer(tspi); 1253 return handle_dma_based_xfer(tspi); 1254 } 1255 1256 static irqreturn_t tegra_spi_isr(int irq, void *context_data) 1257 { 1258 struct tegra_spi_data *tspi = context_data; 1259 1260 tspi->status_reg = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 1261 if (tspi->cur_direction & DATA_DIR_TX) 1262 tspi->tx_status = tspi->status_reg & 1263 (SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF); 1264 1265 if (tspi->cur_direction & DATA_DIR_RX) 1266 tspi->rx_status = tspi->status_reg & 1267 (SPI_RX_FIFO_OVF | SPI_RX_FIFO_UNF); 1268 tegra_spi_clear_status(tspi); 1269 1270 return IRQ_WAKE_THREAD; 1271 } 1272 1273 static struct tegra_spi_soc_data tegra114_spi_soc_data = { 1274 .has_intr_mask_reg = false, 1275 }; 1276 1277 static struct tegra_spi_soc_data tegra124_spi_soc_data = { 1278 .has_intr_mask_reg = false, 1279 }; 1280 1281 static struct tegra_spi_soc_data tegra210_spi_soc_data = { 1282 .has_intr_mask_reg = true, 1283 }; 1284 1285 static const struct of_device_id tegra_spi_of_match[] = { 1286 { 1287 .compatible = "nvidia,tegra114-spi", 1288 .data = &tegra114_spi_soc_data, 1289 }, { 1290 .compatible = "nvidia,tegra124-spi", 1291 .data = &tegra124_spi_soc_data, 1292 }, { 1293 .compatible = "nvidia,tegra210-spi", 1294 .data = &tegra210_spi_soc_data, 1295 }, 1296 {} 1297 }; 1298 MODULE_DEVICE_TABLE(of, tegra_spi_of_match); 1299 1300 static int tegra_spi_probe(struct platform_device *pdev) 1301 { 1302 struct spi_master *master; 1303 struct tegra_spi_data *tspi; 1304 struct resource *r; 1305 int ret, spi_irq; 1306 int bus_num; 1307 1308 master = spi_alloc_master(&pdev->dev, sizeof(*tspi)); 1309 if (!master) { 1310 dev_err(&pdev->dev, "master allocation failed\n"); 1311 return -ENOMEM; 1312 } 1313 platform_set_drvdata(pdev, master); 1314 tspi = spi_master_get_devdata(master); 1315 1316 if (of_property_read_u32(pdev->dev.of_node, "spi-max-frequency", 1317 &master->max_speed_hz)) 1318 master->max_speed_hz = 25000000; /* 25MHz */ 1319 1320 /* the spi->mode bits understood by this driver: */ 1321 master->use_gpio_descriptors = true; 1322 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST | 1323 SPI_TX_DUAL | SPI_RX_DUAL | SPI_3WIRE; 1324 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); 1325 master->setup = tegra_spi_setup; 1326 master->cleanup = tegra_spi_cleanup; 1327 master->transfer_one_message = tegra_spi_transfer_one_message; 1328 master->set_cs_timing = tegra_spi_set_hw_cs_timing; 1329 master->num_chipselect = MAX_CHIP_SELECT; 1330 master->auto_runtime_pm = true; 1331 bus_num = of_alias_get_id(pdev->dev.of_node, "spi"); 1332 if (bus_num >= 0) 1333 master->bus_num = bus_num; 1334 1335 tspi->master = master; 1336 tspi->dev = &pdev->dev; 1337 spin_lock_init(&tspi->lock); 1338 1339 tspi->soc_data = of_device_get_match_data(&pdev->dev); 1340 if (!tspi->soc_data) { 1341 dev_err(&pdev->dev, "unsupported tegra\n"); 1342 ret = -ENODEV; 1343 goto exit_free_master; 1344 } 1345 1346 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1347 tspi->base = devm_ioremap_resource(&pdev->dev, r); 1348 if (IS_ERR(tspi->base)) { 1349 ret = PTR_ERR(tspi->base); 1350 goto exit_free_master; 1351 } 1352 tspi->phys = r->start; 1353 1354 spi_irq = platform_get_irq(pdev, 0); 1355 tspi->irq = spi_irq; 1356 1357 tspi->clk = devm_clk_get(&pdev->dev, "spi"); 1358 if (IS_ERR(tspi->clk)) { 1359 dev_err(&pdev->dev, "can not get clock\n"); 1360 ret = PTR_ERR(tspi->clk); 1361 goto exit_free_master; 1362 } 1363 1364 tspi->rst = devm_reset_control_get_exclusive(&pdev->dev, "spi"); 1365 if (IS_ERR(tspi->rst)) { 1366 dev_err(&pdev->dev, "can not get reset\n"); 1367 ret = PTR_ERR(tspi->rst); 1368 goto exit_free_master; 1369 } 1370 1371 tspi->max_buf_size = SPI_FIFO_DEPTH << 2; 1372 tspi->dma_buf_size = DEFAULT_SPI_DMA_BUF_LEN; 1373 1374 ret = tegra_spi_init_dma_param(tspi, true); 1375 if (ret < 0) 1376 goto exit_free_master; 1377 ret = tegra_spi_init_dma_param(tspi, false); 1378 if (ret < 0) 1379 goto exit_rx_dma_free; 1380 tspi->max_buf_size = tspi->dma_buf_size; 1381 init_completion(&tspi->tx_dma_complete); 1382 init_completion(&tspi->rx_dma_complete); 1383 1384 init_completion(&tspi->xfer_completion); 1385 1386 pm_runtime_enable(&pdev->dev); 1387 if (!pm_runtime_enabled(&pdev->dev)) { 1388 ret = tegra_spi_runtime_resume(&pdev->dev); 1389 if (ret) 1390 goto exit_pm_disable; 1391 } 1392 1393 ret = pm_runtime_get_sync(&pdev->dev); 1394 if (ret < 0) { 1395 dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret); 1396 pm_runtime_put_noidle(&pdev->dev); 1397 goto exit_pm_disable; 1398 } 1399 1400 reset_control_assert(tspi->rst); 1401 udelay(2); 1402 reset_control_deassert(tspi->rst); 1403 tspi->def_command1_reg = SPI_M_S; 1404 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 1405 tspi->spi_cs_timing1 = tegra_spi_readl(tspi, SPI_CS_TIMING1); 1406 tspi->spi_cs_timing2 = tegra_spi_readl(tspi, SPI_CS_TIMING2); 1407 tspi->def_command2_reg = tegra_spi_readl(tspi, SPI_COMMAND2); 1408 tspi->last_used_cs = master->num_chipselect + 1; 1409 pm_runtime_put(&pdev->dev); 1410 ret = request_threaded_irq(tspi->irq, tegra_spi_isr, 1411 tegra_spi_isr_thread, IRQF_ONESHOT, 1412 dev_name(&pdev->dev), tspi); 1413 if (ret < 0) { 1414 dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", 1415 tspi->irq); 1416 goto exit_pm_disable; 1417 } 1418 1419 master->dev.of_node = pdev->dev.of_node; 1420 ret = devm_spi_register_master(&pdev->dev, master); 1421 if (ret < 0) { 1422 dev_err(&pdev->dev, "can not register to master err %d\n", ret); 1423 goto exit_free_irq; 1424 } 1425 return ret; 1426 1427 exit_free_irq: 1428 free_irq(spi_irq, tspi); 1429 exit_pm_disable: 1430 pm_runtime_disable(&pdev->dev); 1431 if (!pm_runtime_status_suspended(&pdev->dev)) 1432 tegra_spi_runtime_suspend(&pdev->dev); 1433 tegra_spi_deinit_dma_param(tspi, false); 1434 exit_rx_dma_free: 1435 tegra_spi_deinit_dma_param(tspi, true); 1436 exit_free_master: 1437 spi_master_put(master); 1438 return ret; 1439 } 1440 1441 static int tegra_spi_remove(struct platform_device *pdev) 1442 { 1443 struct spi_master *master = platform_get_drvdata(pdev); 1444 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1445 1446 free_irq(tspi->irq, tspi); 1447 1448 if (tspi->tx_dma_chan) 1449 tegra_spi_deinit_dma_param(tspi, false); 1450 1451 if (tspi->rx_dma_chan) 1452 tegra_spi_deinit_dma_param(tspi, true); 1453 1454 pm_runtime_disable(&pdev->dev); 1455 if (!pm_runtime_status_suspended(&pdev->dev)) 1456 tegra_spi_runtime_suspend(&pdev->dev); 1457 1458 return 0; 1459 } 1460 1461 #ifdef CONFIG_PM_SLEEP 1462 static int tegra_spi_suspend(struct device *dev) 1463 { 1464 struct spi_master *master = dev_get_drvdata(dev); 1465 1466 return spi_master_suspend(master); 1467 } 1468 1469 static int tegra_spi_resume(struct device *dev) 1470 { 1471 struct spi_master *master = dev_get_drvdata(dev); 1472 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1473 int ret; 1474 1475 ret = pm_runtime_get_sync(dev); 1476 if (ret < 0) { 1477 pm_runtime_put_noidle(dev); 1478 dev_err(dev, "pm runtime failed, e = %d\n", ret); 1479 return ret; 1480 } 1481 tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); 1482 tegra_spi_writel(tspi, tspi->def_command2_reg, SPI_COMMAND2); 1483 tspi->last_used_cs = master->num_chipselect + 1; 1484 pm_runtime_put(dev); 1485 1486 return spi_master_resume(master); 1487 } 1488 #endif 1489 1490 static int tegra_spi_runtime_suspend(struct device *dev) 1491 { 1492 struct spi_master *master = dev_get_drvdata(dev); 1493 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1494 1495 /* Flush all write which are in PPSB queue by reading back */ 1496 tegra_spi_readl(tspi, SPI_COMMAND1); 1497 1498 clk_disable_unprepare(tspi->clk); 1499 return 0; 1500 } 1501 1502 static int tegra_spi_runtime_resume(struct device *dev) 1503 { 1504 struct spi_master *master = dev_get_drvdata(dev); 1505 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1506 int ret; 1507 1508 ret = clk_prepare_enable(tspi->clk); 1509 if (ret < 0) { 1510 dev_err(tspi->dev, "clk_prepare failed: %d\n", ret); 1511 return ret; 1512 } 1513 return 0; 1514 } 1515 1516 static const struct dev_pm_ops tegra_spi_pm_ops = { 1517 SET_RUNTIME_PM_OPS(tegra_spi_runtime_suspend, 1518 tegra_spi_runtime_resume, NULL) 1519 SET_SYSTEM_SLEEP_PM_OPS(tegra_spi_suspend, tegra_spi_resume) 1520 }; 1521 static struct platform_driver tegra_spi_driver = { 1522 .driver = { 1523 .name = "spi-tegra114", 1524 .pm = &tegra_spi_pm_ops, 1525 .of_match_table = tegra_spi_of_match, 1526 }, 1527 .probe = tegra_spi_probe, 1528 .remove = tegra_spi_remove, 1529 }; 1530 module_platform_driver(tegra_spi_driver); 1531 1532 MODULE_ALIAS("platform:spi-tegra114"); 1533 MODULE_DESCRIPTION("NVIDIA Tegra114 SPI Controller Driver"); 1534 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 1535 MODULE_LICENSE("GPL v2"); 1536