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 int ret; 668 669 dma_chan = dma_request_chan(tspi->dev, dma_to_memory ? "rx" : "tx"); 670 if (IS_ERR(dma_chan)) { 671 ret = PTR_ERR(dma_chan); 672 if (ret != -EPROBE_DEFER) 673 dev_err(tspi->dev, 674 "Dma channel is not available: %d\n", ret); 675 return ret; 676 } 677 678 dma_buf = dma_alloc_coherent(tspi->dev, tspi->dma_buf_size, 679 &dma_phys, GFP_KERNEL); 680 if (!dma_buf) { 681 dev_err(tspi->dev, " Not able to allocate the dma buffer\n"); 682 dma_release_channel(dma_chan); 683 return -ENOMEM; 684 } 685 686 if (dma_to_memory) { 687 tspi->rx_dma_chan = dma_chan; 688 tspi->rx_dma_buf = dma_buf; 689 tspi->rx_dma_phys = dma_phys; 690 } else { 691 tspi->tx_dma_chan = dma_chan; 692 tspi->tx_dma_buf = dma_buf; 693 tspi->tx_dma_phys = dma_phys; 694 } 695 return 0; 696 } 697 698 static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, 699 bool dma_to_memory) 700 { 701 u32 *dma_buf; 702 dma_addr_t dma_phys; 703 struct dma_chan *dma_chan; 704 705 if (dma_to_memory) { 706 dma_buf = tspi->rx_dma_buf; 707 dma_chan = tspi->rx_dma_chan; 708 dma_phys = tspi->rx_dma_phys; 709 tspi->rx_dma_chan = NULL; 710 tspi->rx_dma_buf = NULL; 711 } else { 712 dma_buf = tspi->tx_dma_buf; 713 dma_chan = tspi->tx_dma_chan; 714 dma_phys = tspi->tx_dma_phys; 715 tspi->tx_dma_buf = NULL; 716 tspi->tx_dma_chan = NULL; 717 } 718 if (!dma_chan) 719 return; 720 721 dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys); 722 dma_release_channel(dma_chan); 723 } 724 725 static int tegra_spi_set_hw_cs_timing(struct spi_device *spi, 726 struct spi_delay *setup, 727 struct spi_delay *hold, 728 struct spi_delay *inactive) 729 { 730 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 731 u8 setup_dly, hold_dly, inactive_dly; 732 u32 setup_hold; 733 u32 spi_cs_timing; 734 u32 inactive_cycles; 735 u8 cs_state; 736 737 if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) || 738 (hold && hold->unit != SPI_DELAY_UNIT_SCK) || 739 (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) { 740 dev_err(&spi->dev, 741 "Invalid delay unit %d, should be SPI_DELAY_UNIT_SCK\n", 742 SPI_DELAY_UNIT_SCK); 743 return -EINVAL; 744 } 745 746 setup_dly = setup ? setup->value : 0; 747 hold_dly = hold ? hold->value : 0; 748 inactive_dly = inactive ? inactive->value : 0; 749 750 setup_dly = min_t(u8, setup_dly, MAX_SETUP_HOLD_CYCLES); 751 hold_dly = min_t(u8, hold_dly, MAX_SETUP_HOLD_CYCLES); 752 if (setup_dly && hold_dly) { 753 setup_hold = SPI_SETUP_HOLD(setup_dly - 1, hold_dly - 1); 754 spi_cs_timing = SPI_CS_SETUP_HOLD(tspi->spi_cs_timing1, 755 spi->chip_select, 756 setup_hold); 757 if (tspi->spi_cs_timing1 != spi_cs_timing) { 758 tspi->spi_cs_timing1 = spi_cs_timing; 759 tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING1); 760 } 761 } 762 763 inactive_cycles = min_t(u8, inactive_dly, MAX_INACTIVE_CYCLES); 764 if (inactive_cycles) 765 inactive_cycles--; 766 cs_state = inactive_cycles ? 0 : 1; 767 spi_cs_timing = tspi->spi_cs_timing2; 768 SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select, 769 cs_state); 770 SPI_SET_CYCLES_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select, 771 inactive_cycles); 772 if (tspi->spi_cs_timing2 != spi_cs_timing) { 773 tspi->spi_cs_timing2 = spi_cs_timing; 774 tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING2); 775 } 776 777 return 0; 778 } 779 780 static u32 tegra_spi_setup_transfer_one(struct spi_device *spi, 781 struct spi_transfer *t, 782 bool is_first_of_msg, 783 bool is_single_xfer) 784 { 785 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 786 struct tegra_spi_client_data *cdata = spi->controller_data; 787 u32 speed = t->speed_hz; 788 u8 bits_per_word = t->bits_per_word; 789 u32 command1, command2; 790 int req_mode; 791 u32 tx_tap = 0, rx_tap = 0; 792 793 if (speed != tspi->cur_speed) { 794 clk_set_rate(tspi->clk, speed); 795 tspi->cur_speed = speed; 796 } 797 798 tspi->cur_spi = spi; 799 tspi->cur_pos = 0; 800 tspi->cur_rx_pos = 0; 801 tspi->cur_tx_pos = 0; 802 tspi->curr_xfer = t; 803 804 if (is_first_of_msg) { 805 tegra_spi_clear_status(tspi); 806 807 command1 = tspi->def_command1_reg; 808 command1 |= SPI_BIT_LENGTH(bits_per_word - 1); 809 810 command1 &= ~SPI_CONTROL_MODE_MASK; 811 req_mode = spi->mode & 0x3; 812 if (req_mode == SPI_MODE_0) 813 command1 |= SPI_CONTROL_MODE_0; 814 else if (req_mode == SPI_MODE_1) 815 command1 |= SPI_CONTROL_MODE_1; 816 else if (req_mode == SPI_MODE_2) 817 command1 |= SPI_CONTROL_MODE_2; 818 else if (req_mode == SPI_MODE_3) 819 command1 |= SPI_CONTROL_MODE_3; 820 821 if (spi->mode & SPI_LSB_FIRST) 822 command1 |= SPI_LSBIT_FE; 823 else 824 command1 &= ~SPI_LSBIT_FE; 825 826 if (spi->mode & SPI_3WIRE) 827 command1 |= SPI_BIDIROE; 828 else 829 command1 &= ~SPI_BIDIROE; 830 831 if (tspi->cs_control) { 832 if (tspi->cs_control != spi) 833 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 834 tspi->cs_control = NULL; 835 } else 836 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 837 838 /* GPIO based chip select control */ 839 if (spi->cs_gpiod) 840 gpiod_set_value(spi->cs_gpiod, 1); 841 842 if (is_single_xfer && !(t->cs_change)) { 843 tspi->use_hw_based_cs = true; 844 command1 &= ~(SPI_CS_SW_HW | SPI_CS_SW_VAL); 845 } else { 846 tspi->use_hw_based_cs = false; 847 command1 |= SPI_CS_SW_HW; 848 if (spi->mode & SPI_CS_HIGH) 849 command1 |= SPI_CS_SW_VAL; 850 else 851 command1 &= ~SPI_CS_SW_VAL; 852 } 853 854 if (tspi->last_used_cs != spi->chip_select) { 855 if (cdata && cdata->tx_clk_tap_delay) 856 tx_tap = cdata->tx_clk_tap_delay; 857 if (cdata && cdata->rx_clk_tap_delay) 858 rx_tap = cdata->rx_clk_tap_delay; 859 command2 = SPI_TX_TAP_DELAY(tx_tap) | 860 SPI_RX_TAP_DELAY(rx_tap); 861 if (command2 != tspi->def_command2_reg) 862 tegra_spi_writel(tspi, command2, SPI_COMMAND2); 863 tspi->last_used_cs = spi->chip_select; 864 } 865 866 } else { 867 command1 = tspi->command1_reg; 868 command1 &= ~SPI_BIT_LENGTH(~0); 869 command1 |= SPI_BIT_LENGTH(bits_per_word - 1); 870 } 871 872 return command1; 873 } 874 875 static int tegra_spi_start_transfer_one(struct spi_device *spi, 876 struct spi_transfer *t, u32 command1) 877 { 878 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 879 unsigned total_fifo_words; 880 int ret; 881 882 total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t); 883 884 if (t->rx_nbits == SPI_NBITS_DUAL || t->tx_nbits == SPI_NBITS_DUAL) 885 command1 |= SPI_BOTH_EN_BIT; 886 else 887 command1 &= ~SPI_BOTH_EN_BIT; 888 889 if (tspi->is_packed) 890 command1 |= SPI_PACKED; 891 else 892 command1 &= ~SPI_PACKED; 893 894 command1 &= ~(SPI_CS_SEL_MASK | SPI_TX_EN | SPI_RX_EN); 895 tspi->cur_direction = 0; 896 if (t->rx_buf) { 897 command1 |= SPI_RX_EN; 898 tspi->cur_direction |= DATA_DIR_RX; 899 } 900 if (t->tx_buf) { 901 command1 |= SPI_TX_EN; 902 tspi->cur_direction |= DATA_DIR_TX; 903 } 904 command1 |= SPI_CS_SEL(spi->chip_select); 905 tegra_spi_writel(tspi, command1, SPI_COMMAND1); 906 tspi->command1_reg = command1; 907 908 dev_dbg(tspi->dev, "The def 0x%x and written 0x%x\n", 909 tspi->def_command1_reg, (unsigned)command1); 910 911 ret = tegra_spi_flush_fifos(tspi); 912 if (ret < 0) 913 return ret; 914 if (total_fifo_words > SPI_FIFO_DEPTH) 915 ret = tegra_spi_start_dma_based_transfer(tspi, t); 916 else 917 ret = tegra_spi_start_cpu_based_transfer(tspi, t); 918 return ret; 919 } 920 921 static struct tegra_spi_client_data 922 *tegra_spi_parse_cdata_dt(struct spi_device *spi) 923 { 924 struct tegra_spi_client_data *cdata; 925 struct device_node *slave_np; 926 927 slave_np = spi->dev.of_node; 928 if (!slave_np) { 929 dev_dbg(&spi->dev, "device node not found\n"); 930 return NULL; 931 } 932 933 cdata = kzalloc(sizeof(*cdata), GFP_KERNEL); 934 if (!cdata) 935 return NULL; 936 937 of_property_read_u32(slave_np, "nvidia,tx-clk-tap-delay", 938 &cdata->tx_clk_tap_delay); 939 of_property_read_u32(slave_np, "nvidia,rx-clk-tap-delay", 940 &cdata->rx_clk_tap_delay); 941 return cdata; 942 } 943 944 static void tegra_spi_cleanup(struct spi_device *spi) 945 { 946 struct tegra_spi_client_data *cdata = spi->controller_data; 947 948 spi->controller_data = NULL; 949 if (spi->dev.of_node) 950 kfree(cdata); 951 } 952 953 static int tegra_spi_setup(struct spi_device *spi) 954 { 955 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 956 struct tegra_spi_client_data *cdata = spi->controller_data; 957 u32 val; 958 unsigned long flags; 959 int ret; 960 961 dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n", 962 spi->bits_per_word, 963 spi->mode & SPI_CPOL ? "" : "~", 964 spi->mode & SPI_CPHA ? "" : "~", 965 spi->max_speed_hz); 966 967 if (!cdata) { 968 cdata = tegra_spi_parse_cdata_dt(spi); 969 spi->controller_data = cdata; 970 } 971 972 ret = pm_runtime_get_sync(tspi->dev); 973 if (ret < 0) { 974 dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret); 975 if (cdata) 976 tegra_spi_cleanup(spi); 977 return ret; 978 } 979 980 if (tspi->soc_data->has_intr_mask_reg) { 981 val = tegra_spi_readl(tspi, SPI_INTR_MASK); 982 val &= ~SPI_INTR_ALL_MASK; 983 tegra_spi_writel(tspi, val, SPI_INTR_MASK); 984 } 985 986 spin_lock_irqsave(&tspi->lock, flags); 987 /* GPIO based chip select control */ 988 if (spi->cs_gpiod) 989 gpiod_set_value(spi->cs_gpiod, 0); 990 991 val = tspi->def_command1_reg; 992 if (spi->mode & SPI_CS_HIGH) 993 val &= ~SPI_CS_POL_INACTIVE(spi->chip_select); 994 else 995 val |= SPI_CS_POL_INACTIVE(spi->chip_select); 996 tspi->def_command1_reg = val; 997 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 998 spin_unlock_irqrestore(&tspi->lock, flags); 999 1000 pm_runtime_put(tspi->dev); 1001 return 0; 1002 } 1003 1004 static void tegra_spi_transfer_end(struct spi_device *spi) 1005 { 1006 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); 1007 int cs_val = (spi->mode & SPI_CS_HIGH) ? 0 : 1; 1008 1009 /* GPIO based chip select control */ 1010 if (spi->cs_gpiod) 1011 gpiod_set_value(spi->cs_gpiod, 0); 1012 1013 if (!tspi->use_hw_based_cs) { 1014 if (cs_val) 1015 tspi->command1_reg |= SPI_CS_SW_VAL; 1016 else 1017 tspi->command1_reg &= ~SPI_CS_SW_VAL; 1018 tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); 1019 } 1020 1021 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 1022 } 1023 1024 static void tegra_spi_dump_regs(struct tegra_spi_data *tspi) 1025 { 1026 dev_dbg(tspi->dev, "============ SPI REGISTER DUMP ============\n"); 1027 dev_dbg(tspi->dev, "Command1: 0x%08x | Command2: 0x%08x\n", 1028 tegra_spi_readl(tspi, SPI_COMMAND1), 1029 tegra_spi_readl(tspi, SPI_COMMAND2)); 1030 dev_dbg(tspi->dev, "DMA_CTL: 0x%08x | DMA_BLK: 0x%08x\n", 1031 tegra_spi_readl(tspi, SPI_DMA_CTL), 1032 tegra_spi_readl(tspi, SPI_DMA_BLK)); 1033 dev_dbg(tspi->dev, "TRANS_STAT: 0x%08x | FIFO_STATUS: 0x%08x\n", 1034 tegra_spi_readl(tspi, SPI_TRANS_STATUS), 1035 tegra_spi_readl(tspi, SPI_FIFO_STATUS)); 1036 } 1037 1038 static int tegra_spi_transfer_one_message(struct spi_master *master, 1039 struct spi_message *msg) 1040 { 1041 bool is_first_msg = true; 1042 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1043 struct spi_transfer *xfer; 1044 struct spi_device *spi = msg->spi; 1045 int ret; 1046 bool skip = false; 1047 int single_xfer; 1048 1049 msg->status = 0; 1050 msg->actual_length = 0; 1051 1052 single_xfer = list_is_singular(&msg->transfers); 1053 list_for_each_entry(xfer, &msg->transfers, transfer_list) { 1054 u32 cmd1; 1055 1056 reinit_completion(&tspi->xfer_completion); 1057 1058 cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg, 1059 single_xfer); 1060 1061 if (!xfer->len) { 1062 ret = 0; 1063 skip = true; 1064 goto complete_xfer; 1065 } 1066 1067 ret = tegra_spi_start_transfer_one(spi, xfer, cmd1); 1068 if (ret < 0) { 1069 dev_err(tspi->dev, 1070 "spi can not start transfer, err %d\n", ret); 1071 goto complete_xfer; 1072 } 1073 1074 is_first_msg = false; 1075 ret = wait_for_completion_timeout(&tspi->xfer_completion, 1076 SPI_DMA_TIMEOUT); 1077 if (WARN_ON(ret == 0)) { 1078 dev_err(tspi->dev, 1079 "spi transfer timeout, err %d\n", ret); 1080 if (tspi->is_curr_dma_xfer && 1081 (tspi->cur_direction & DATA_DIR_TX)) 1082 dmaengine_terminate_all(tspi->tx_dma_chan); 1083 if (tspi->is_curr_dma_xfer && 1084 (tspi->cur_direction & DATA_DIR_RX)) 1085 dmaengine_terminate_all(tspi->rx_dma_chan); 1086 ret = -EIO; 1087 tegra_spi_dump_regs(tspi); 1088 tegra_spi_flush_fifos(tspi); 1089 reset_control_assert(tspi->rst); 1090 udelay(2); 1091 reset_control_deassert(tspi->rst); 1092 tspi->last_used_cs = master->num_chipselect + 1; 1093 goto complete_xfer; 1094 } 1095 1096 if (tspi->tx_status || tspi->rx_status) { 1097 dev_err(tspi->dev, "Error in Transfer\n"); 1098 ret = -EIO; 1099 tegra_spi_dump_regs(tspi); 1100 goto complete_xfer; 1101 } 1102 msg->actual_length += xfer->len; 1103 1104 complete_xfer: 1105 if (ret < 0 || skip) { 1106 tegra_spi_transfer_end(spi); 1107 spi_transfer_delay_exec(xfer); 1108 goto exit; 1109 } else if (list_is_last(&xfer->transfer_list, 1110 &msg->transfers)) { 1111 if (xfer->cs_change) 1112 tspi->cs_control = spi; 1113 else { 1114 tegra_spi_transfer_end(spi); 1115 spi_transfer_delay_exec(xfer); 1116 } 1117 } else if (xfer->cs_change) { 1118 tegra_spi_transfer_end(spi); 1119 spi_transfer_delay_exec(xfer); 1120 } 1121 1122 } 1123 ret = 0; 1124 exit: 1125 msg->status = ret; 1126 spi_finalize_current_message(master); 1127 return ret; 1128 } 1129 1130 static irqreturn_t handle_cpu_based_xfer(struct tegra_spi_data *tspi) 1131 { 1132 struct spi_transfer *t = tspi->curr_xfer; 1133 unsigned long flags; 1134 1135 spin_lock_irqsave(&tspi->lock, flags); 1136 if (tspi->tx_status || tspi->rx_status) { 1137 dev_err(tspi->dev, "CpuXfer ERROR bit set 0x%x\n", 1138 tspi->status_reg); 1139 dev_err(tspi->dev, "CpuXfer 0x%08x:0x%08x\n", 1140 tspi->command1_reg, tspi->dma_control_reg); 1141 tegra_spi_dump_regs(tspi); 1142 tegra_spi_flush_fifos(tspi); 1143 complete(&tspi->xfer_completion); 1144 spin_unlock_irqrestore(&tspi->lock, flags); 1145 reset_control_assert(tspi->rst); 1146 udelay(2); 1147 reset_control_deassert(tspi->rst); 1148 return IRQ_HANDLED; 1149 } 1150 1151 if (tspi->cur_direction & DATA_DIR_RX) 1152 tegra_spi_read_rx_fifo_to_client_rxbuf(tspi, t); 1153 1154 if (tspi->cur_direction & DATA_DIR_TX) 1155 tspi->cur_pos = tspi->cur_tx_pos; 1156 else 1157 tspi->cur_pos = tspi->cur_rx_pos; 1158 1159 if (tspi->cur_pos == t->len) { 1160 complete(&tspi->xfer_completion); 1161 goto exit; 1162 } 1163 1164 tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, tspi, t); 1165 tegra_spi_start_cpu_based_transfer(tspi, t); 1166 exit: 1167 spin_unlock_irqrestore(&tspi->lock, flags); 1168 return IRQ_HANDLED; 1169 } 1170 1171 static irqreturn_t handle_dma_based_xfer(struct tegra_spi_data *tspi) 1172 { 1173 struct spi_transfer *t = tspi->curr_xfer; 1174 long wait_status; 1175 int err = 0; 1176 unsigned total_fifo_words; 1177 unsigned long flags; 1178 1179 /* Abort dmas if any error */ 1180 if (tspi->cur_direction & DATA_DIR_TX) { 1181 if (tspi->tx_status) { 1182 dmaengine_terminate_all(tspi->tx_dma_chan); 1183 err += 1; 1184 } else { 1185 wait_status = wait_for_completion_interruptible_timeout( 1186 &tspi->tx_dma_complete, SPI_DMA_TIMEOUT); 1187 if (wait_status <= 0) { 1188 dmaengine_terminate_all(tspi->tx_dma_chan); 1189 dev_err(tspi->dev, "TxDma Xfer failed\n"); 1190 err += 1; 1191 } 1192 } 1193 } 1194 1195 if (tspi->cur_direction & DATA_DIR_RX) { 1196 if (tspi->rx_status) { 1197 dmaengine_terminate_all(tspi->rx_dma_chan); 1198 err += 2; 1199 } else { 1200 wait_status = wait_for_completion_interruptible_timeout( 1201 &tspi->rx_dma_complete, SPI_DMA_TIMEOUT); 1202 if (wait_status <= 0) { 1203 dmaengine_terminate_all(tspi->rx_dma_chan); 1204 dev_err(tspi->dev, "RxDma Xfer failed\n"); 1205 err += 2; 1206 } 1207 } 1208 } 1209 1210 spin_lock_irqsave(&tspi->lock, flags); 1211 if (err) { 1212 dev_err(tspi->dev, "DmaXfer: ERROR bit set 0x%x\n", 1213 tspi->status_reg); 1214 dev_err(tspi->dev, "DmaXfer 0x%08x:0x%08x\n", 1215 tspi->command1_reg, tspi->dma_control_reg); 1216 tegra_spi_dump_regs(tspi); 1217 tegra_spi_flush_fifos(tspi); 1218 complete(&tspi->xfer_completion); 1219 spin_unlock_irqrestore(&tspi->lock, flags); 1220 reset_control_assert(tspi->rst); 1221 udelay(2); 1222 reset_control_deassert(tspi->rst); 1223 return IRQ_HANDLED; 1224 } 1225 1226 if (tspi->cur_direction & DATA_DIR_RX) 1227 tegra_spi_copy_spi_rxbuf_to_client_rxbuf(tspi, t); 1228 1229 if (tspi->cur_direction & DATA_DIR_TX) 1230 tspi->cur_pos = tspi->cur_tx_pos; 1231 else 1232 tspi->cur_pos = tspi->cur_rx_pos; 1233 1234 if (tspi->cur_pos == t->len) { 1235 complete(&tspi->xfer_completion); 1236 goto exit; 1237 } 1238 1239 /* Continue transfer in current message */ 1240 total_fifo_words = tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, 1241 tspi, t); 1242 if (total_fifo_words > SPI_FIFO_DEPTH) 1243 err = tegra_spi_start_dma_based_transfer(tspi, t); 1244 else 1245 err = tegra_spi_start_cpu_based_transfer(tspi, t); 1246 1247 exit: 1248 spin_unlock_irqrestore(&tspi->lock, flags); 1249 return IRQ_HANDLED; 1250 } 1251 1252 static irqreturn_t tegra_spi_isr_thread(int irq, void *context_data) 1253 { 1254 struct tegra_spi_data *tspi = context_data; 1255 1256 if (!tspi->is_curr_dma_xfer) 1257 return handle_cpu_based_xfer(tspi); 1258 return handle_dma_based_xfer(tspi); 1259 } 1260 1261 static irqreturn_t tegra_spi_isr(int irq, void *context_data) 1262 { 1263 struct tegra_spi_data *tspi = context_data; 1264 1265 tspi->status_reg = tegra_spi_readl(tspi, SPI_FIFO_STATUS); 1266 if (tspi->cur_direction & DATA_DIR_TX) 1267 tspi->tx_status = tspi->status_reg & 1268 (SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF); 1269 1270 if (tspi->cur_direction & DATA_DIR_RX) 1271 tspi->rx_status = tspi->status_reg & 1272 (SPI_RX_FIFO_OVF | SPI_RX_FIFO_UNF); 1273 tegra_spi_clear_status(tspi); 1274 1275 return IRQ_WAKE_THREAD; 1276 } 1277 1278 static struct tegra_spi_soc_data tegra114_spi_soc_data = { 1279 .has_intr_mask_reg = false, 1280 }; 1281 1282 static struct tegra_spi_soc_data tegra124_spi_soc_data = { 1283 .has_intr_mask_reg = false, 1284 }; 1285 1286 static struct tegra_spi_soc_data tegra210_spi_soc_data = { 1287 .has_intr_mask_reg = true, 1288 }; 1289 1290 static const struct of_device_id tegra_spi_of_match[] = { 1291 { 1292 .compatible = "nvidia,tegra114-spi", 1293 .data = &tegra114_spi_soc_data, 1294 }, { 1295 .compatible = "nvidia,tegra124-spi", 1296 .data = &tegra124_spi_soc_data, 1297 }, { 1298 .compatible = "nvidia,tegra210-spi", 1299 .data = &tegra210_spi_soc_data, 1300 }, 1301 {} 1302 }; 1303 MODULE_DEVICE_TABLE(of, tegra_spi_of_match); 1304 1305 static int tegra_spi_probe(struct platform_device *pdev) 1306 { 1307 struct spi_master *master; 1308 struct tegra_spi_data *tspi; 1309 struct resource *r; 1310 int ret, spi_irq; 1311 int bus_num; 1312 1313 master = spi_alloc_master(&pdev->dev, sizeof(*tspi)); 1314 if (!master) { 1315 dev_err(&pdev->dev, "master allocation failed\n"); 1316 return -ENOMEM; 1317 } 1318 platform_set_drvdata(pdev, master); 1319 tspi = spi_master_get_devdata(master); 1320 1321 if (of_property_read_u32(pdev->dev.of_node, "spi-max-frequency", 1322 &master->max_speed_hz)) 1323 master->max_speed_hz = 25000000; /* 25MHz */ 1324 1325 /* the spi->mode bits understood by this driver: */ 1326 master->use_gpio_descriptors = true; 1327 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST | 1328 SPI_TX_DUAL | SPI_RX_DUAL | SPI_3WIRE; 1329 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); 1330 master->setup = tegra_spi_setup; 1331 master->cleanup = tegra_spi_cleanup; 1332 master->transfer_one_message = tegra_spi_transfer_one_message; 1333 master->set_cs_timing = tegra_spi_set_hw_cs_timing; 1334 master->num_chipselect = MAX_CHIP_SELECT; 1335 master->auto_runtime_pm = true; 1336 bus_num = of_alias_get_id(pdev->dev.of_node, "spi"); 1337 if (bus_num >= 0) 1338 master->bus_num = bus_num; 1339 1340 tspi->master = master; 1341 tspi->dev = &pdev->dev; 1342 spin_lock_init(&tspi->lock); 1343 1344 tspi->soc_data = of_device_get_match_data(&pdev->dev); 1345 if (!tspi->soc_data) { 1346 dev_err(&pdev->dev, "unsupported tegra\n"); 1347 ret = -ENODEV; 1348 goto exit_free_master; 1349 } 1350 1351 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1352 tspi->base = devm_ioremap_resource(&pdev->dev, r); 1353 if (IS_ERR(tspi->base)) { 1354 ret = PTR_ERR(tspi->base); 1355 goto exit_free_master; 1356 } 1357 tspi->phys = r->start; 1358 1359 spi_irq = platform_get_irq(pdev, 0); 1360 tspi->irq = spi_irq; 1361 1362 tspi->clk = devm_clk_get(&pdev->dev, "spi"); 1363 if (IS_ERR(tspi->clk)) { 1364 dev_err(&pdev->dev, "can not get clock\n"); 1365 ret = PTR_ERR(tspi->clk); 1366 goto exit_free_master; 1367 } 1368 1369 tspi->rst = devm_reset_control_get_exclusive(&pdev->dev, "spi"); 1370 if (IS_ERR(tspi->rst)) { 1371 dev_err(&pdev->dev, "can not get reset\n"); 1372 ret = PTR_ERR(tspi->rst); 1373 goto exit_free_master; 1374 } 1375 1376 tspi->max_buf_size = SPI_FIFO_DEPTH << 2; 1377 tspi->dma_buf_size = DEFAULT_SPI_DMA_BUF_LEN; 1378 1379 ret = tegra_spi_init_dma_param(tspi, true); 1380 if (ret < 0) 1381 goto exit_free_master; 1382 ret = tegra_spi_init_dma_param(tspi, false); 1383 if (ret < 0) 1384 goto exit_rx_dma_free; 1385 tspi->max_buf_size = tspi->dma_buf_size; 1386 init_completion(&tspi->tx_dma_complete); 1387 init_completion(&tspi->rx_dma_complete); 1388 1389 init_completion(&tspi->xfer_completion); 1390 1391 pm_runtime_enable(&pdev->dev); 1392 if (!pm_runtime_enabled(&pdev->dev)) { 1393 ret = tegra_spi_runtime_resume(&pdev->dev); 1394 if (ret) 1395 goto exit_pm_disable; 1396 } 1397 1398 ret = pm_runtime_get_sync(&pdev->dev); 1399 if (ret < 0) { 1400 dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret); 1401 goto exit_pm_disable; 1402 } 1403 1404 reset_control_assert(tspi->rst); 1405 udelay(2); 1406 reset_control_deassert(tspi->rst); 1407 tspi->def_command1_reg = SPI_M_S; 1408 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); 1409 tspi->spi_cs_timing1 = tegra_spi_readl(tspi, SPI_CS_TIMING1); 1410 tspi->spi_cs_timing2 = tegra_spi_readl(tspi, SPI_CS_TIMING2); 1411 tspi->def_command2_reg = tegra_spi_readl(tspi, SPI_COMMAND2); 1412 tspi->last_used_cs = master->num_chipselect + 1; 1413 pm_runtime_put(&pdev->dev); 1414 ret = request_threaded_irq(tspi->irq, tegra_spi_isr, 1415 tegra_spi_isr_thread, IRQF_ONESHOT, 1416 dev_name(&pdev->dev), tspi); 1417 if (ret < 0) { 1418 dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n", 1419 tspi->irq); 1420 goto exit_pm_disable; 1421 } 1422 1423 master->dev.of_node = pdev->dev.of_node; 1424 ret = devm_spi_register_master(&pdev->dev, master); 1425 if (ret < 0) { 1426 dev_err(&pdev->dev, "can not register to master err %d\n", ret); 1427 goto exit_free_irq; 1428 } 1429 return ret; 1430 1431 exit_free_irq: 1432 free_irq(spi_irq, tspi); 1433 exit_pm_disable: 1434 pm_runtime_disable(&pdev->dev); 1435 if (!pm_runtime_status_suspended(&pdev->dev)) 1436 tegra_spi_runtime_suspend(&pdev->dev); 1437 tegra_spi_deinit_dma_param(tspi, false); 1438 exit_rx_dma_free: 1439 tegra_spi_deinit_dma_param(tspi, true); 1440 exit_free_master: 1441 spi_master_put(master); 1442 return ret; 1443 } 1444 1445 static int tegra_spi_remove(struct platform_device *pdev) 1446 { 1447 struct spi_master *master = platform_get_drvdata(pdev); 1448 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1449 1450 free_irq(tspi->irq, tspi); 1451 1452 if (tspi->tx_dma_chan) 1453 tegra_spi_deinit_dma_param(tspi, false); 1454 1455 if (tspi->rx_dma_chan) 1456 tegra_spi_deinit_dma_param(tspi, true); 1457 1458 pm_runtime_disable(&pdev->dev); 1459 if (!pm_runtime_status_suspended(&pdev->dev)) 1460 tegra_spi_runtime_suspend(&pdev->dev); 1461 1462 return 0; 1463 } 1464 1465 #ifdef CONFIG_PM_SLEEP 1466 static int tegra_spi_suspend(struct device *dev) 1467 { 1468 struct spi_master *master = dev_get_drvdata(dev); 1469 1470 return spi_master_suspend(master); 1471 } 1472 1473 static int tegra_spi_resume(struct device *dev) 1474 { 1475 struct spi_master *master = dev_get_drvdata(dev); 1476 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1477 int ret; 1478 1479 ret = pm_runtime_get_sync(dev); 1480 if (ret < 0) { 1481 dev_err(dev, "pm runtime failed, e = %d\n", ret); 1482 return ret; 1483 } 1484 tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); 1485 tegra_spi_writel(tspi, tspi->def_command2_reg, SPI_COMMAND2); 1486 tspi->last_used_cs = master->num_chipselect + 1; 1487 pm_runtime_put(dev); 1488 1489 return spi_master_resume(master); 1490 } 1491 #endif 1492 1493 static int tegra_spi_runtime_suspend(struct device *dev) 1494 { 1495 struct spi_master *master = dev_get_drvdata(dev); 1496 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1497 1498 /* Flush all write which are in PPSB queue by reading back */ 1499 tegra_spi_readl(tspi, SPI_COMMAND1); 1500 1501 clk_disable_unprepare(tspi->clk); 1502 return 0; 1503 } 1504 1505 static int tegra_spi_runtime_resume(struct device *dev) 1506 { 1507 struct spi_master *master = dev_get_drvdata(dev); 1508 struct tegra_spi_data *tspi = spi_master_get_devdata(master); 1509 int ret; 1510 1511 ret = clk_prepare_enable(tspi->clk); 1512 if (ret < 0) { 1513 dev_err(tspi->dev, "clk_prepare failed: %d\n", ret); 1514 return ret; 1515 } 1516 return 0; 1517 } 1518 1519 static const struct dev_pm_ops tegra_spi_pm_ops = { 1520 SET_RUNTIME_PM_OPS(tegra_spi_runtime_suspend, 1521 tegra_spi_runtime_resume, NULL) 1522 SET_SYSTEM_SLEEP_PM_OPS(tegra_spi_suspend, tegra_spi_resume) 1523 }; 1524 static struct platform_driver tegra_spi_driver = { 1525 .driver = { 1526 .name = "spi-tegra114", 1527 .pm = &tegra_spi_pm_ops, 1528 .of_match_table = tegra_spi_of_match, 1529 }, 1530 .probe = tegra_spi_probe, 1531 .remove = tegra_spi_remove, 1532 }; 1533 module_platform_driver(tegra_spi_driver); 1534 1535 MODULE_ALIAS("platform:spi-tegra114"); 1536 MODULE_DESCRIPTION("NVIDIA Tegra114 SPI Controller Driver"); 1537 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 1538 MODULE_LICENSE("GPL v2"); 1539