1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * Copyright (C) 2019 Xilinx, Inc. 4 * 5 * Author: Naga Sureshkumar Relli <nagasure@xilinx.com> 6 */ 7 8#include <linux/clk.h> 9#include <linux/delay.h> 10#include <linux/interrupt.h> 11#include <linux/io.h> 12#include <linux/module.h> 13#include <linux/of_irq.h> 14#include <linux/of_address.h> 15#include <linux/platform_device.h> 16#include <linux/spi/spi.h> 17#include <linux/workqueue.h> 18#include <linux/spi/spi-mem.h> 19 20/* Register offset definitions */ 21#define ZYNQ_QSPI_CONFIG_OFFSET 0x00 /* Configuration Register, RW */ 22#define ZYNQ_QSPI_STATUS_OFFSET 0x04 /* Interrupt Status Register, RO */ 23#define ZYNQ_QSPI_IEN_OFFSET 0x08 /* Interrupt Enable Register, WO */ 24#define ZYNQ_QSPI_IDIS_OFFSET 0x0C /* Interrupt Disable Reg, WO */ 25#define ZYNQ_QSPI_IMASK_OFFSET 0x10 /* Interrupt Enabled Mask Reg,RO */ 26#define ZYNQ_QSPI_ENABLE_OFFSET 0x14 /* Enable/Disable Register, RW */ 27#define ZYNQ_QSPI_DELAY_OFFSET 0x18 /* Delay Register, RW */ 28#define ZYNQ_QSPI_TXD_00_00_OFFSET 0x1C /* Transmit 4-byte inst, WO */ 29#define ZYNQ_QSPI_TXD_00_01_OFFSET 0x80 /* Transmit 1-byte inst, WO */ 30#define ZYNQ_QSPI_TXD_00_10_OFFSET 0x84 /* Transmit 2-byte inst, WO */ 31#define ZYNQ_QSPI_TXD_00_11_OFFSET 0x88 /* Transmit 3-byte inst, WO */ 32#define ZYNQ_QSPI_RXD_OFFSET 0x20 /* Data Receive Register, RO */ 33#define ZYNQ_QSPI_SIC_OFFSET 0x24 /* Slave Idle Count Register, RW */ 34#define ZYNQ_QSPI_TX_THRESH_OFFSET 0x28 /* TX FIFO Watermark Reg, RW */ 35#define ZYNQ_QSPI_RX_THRESH_OFFSET 0x2C /* RX FIFO Watermark Reg, RW */ 36#define ZYNQ_QSPI_GPIO_OFFSET 0x30 /* GPIO Register, RW */ 37#define ZYNQ_QSPI_LINEAR_CFG_OFFSET 0xA0 /* Linear Adapter Config Ref, RW */ 38#define ZYNQ_QSPI_MOD_ID_OFFSET 0xFC /* Module ID Register, RO */ 39 40/* 41 * QSPI Configuration Register bit Masks 42 * 43 * This register contains various control bits that effect the operation 44 * of the QSPI controller 45 */ 46#define ZYNQ_QSPI_CONFIG_IFMODE_MASK BIT(31) /* Flash Memory Interface */ 47#define ZYNQ_QSPI_CONFIG_MANSRT_MASK BIT(16) /* Manual TX Start */ 48#define ZYNQ_QSPI_CONFIG_MANSRTEN_MASK BIT(15) /* Enable Manual TX Mode */ 49#define ZYNQ_QSPI_CONFIG_SSFORCE_MASK BIT(14) /* Manual Chip Select */ 50#define ZYNQ_QSPI_CONFIG_BDRATE_MASK GENMASK(5, 3) /* Baud Rate Mask */ 51#define ZYNQ_QSPI_CONFIG_CPHA_MASK BIT(2) /* Clock Phase Control */ 52#define ZYNQ_QSPI_CONFIG_CPOL_MASK BIT(1) /* Clock Polarity Control */ 53#define ZYNQ_QSPI_CONFIG_FWIDTH_MASK GENMASK(7, 6) /* FIFO width */ 54#define ZYNQ_QSPI_CONFIG_MSTREN_MASK BIT(0) /* Master Mode */ 55 56/* 57 * QSPI Configuration Register - Baud rate and target select 58 * 59 * These are the values used in the calculation of baud rate divisor and 60 * setting the target select. 61 */ 62#define ZYNQ_QSPI_CONFIG_BAUD_DIV_MAX GENMASK(2, 0) /* Baud rate maximum */ 63#define ZYNQ_QSPI_CONFIG_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift */ 64#define ZYNQ_QSPI_CONFIG_PCS BIT(10) /* Peripheral Chip Select */ 65 66/* 67 * QSPI Interrupt Registers bit Masks 68 * 69 * All the four interrupt registers (Status/Mask/Enable/Disable) have the same 70 * bit definitions. 71 */ 72#define ZYNQ_QSPI_IXR_RX_OVERFLOW_MASK BIT(0) /* QSPI RX FIFO Overflow */ 73#define ZYNQ_QSPI_IXR_TXNFULL_MASK BIT(2) /* QSPI TX FIFO Overflow */ 74#define ZYNQ_QSPI_IXR_TXFULL_MASK BIT(3) /* QSPI TX FIFO is full */ 75#define ZYNQ_QSPI_IXR_RXNEMTY_MASK BIT(4) /* QSPI RX FIFO Not Empty */ 76#define ZYNQ_QSPI_IXR_RXF_FULL_MASK BIT(5) /* QSPI RX FIFO is full */ 77#define ZYNQ_QSPI_IXR_TXF_UNDRFLOW_MASK BIT(6) /* QSPI TX FIFO Underflow */ 78#define ZYNQ_QSPI_IXR_ALL_MASK (ZYNQ_QSPI_IXR_RX_OVERFLOW_MASK | \ 79 ZYNQ_QSPI_IXR_TXNFULL_MASK | \ 80 ZYNQ_QSPI_IXR_TXFULL_MASK | \ 81 ZYNQ_QSPI_IXR_RXNEMTY_MASK | \ 82 ZYNQ_QSPI_IXR_RXF_FULL_MASK | \ 83 ZYNQ_QSPI_IXR_TXF_UNDRFLOW_MASK) 84#define ZYNQ_QSPI_IXR_RXTX_MASK (ZYNQ_QSPI_IXR_TXNFULL_MASK | \ 85 ZYNQ_QSPI_IXR_RXNEMTY_MASK) 86 87/* 88 * QSPI Enable Register bit Masks 89 * 90 * This register is used to enable or disable the QSPI controller 91 */ 92#define ZYNQ_QSPI_ENABLE_ENABLE_MASK BIT(0) /* QSPI Enable Bit Mask */ 93 94/* 95 * QSPI Linear Configuration Register 96 * 97 * It is named Linear Configuration but it controls other modes when not in 98 * linear mode also. 99 */ 100#define ZYNQ_QSPI_LCFG_TWO_MEM BIT(30) /* LQSPI Two memories */ 101#define ZYNQ_QSPI_LCFG_SEP_BUS BIT(29) /* LQSPI Separate bus */ 102#define ZYNQ_QSPI_LCFG_U_PAGE BIT(28) /* LQSPI Upper Page */ 103 104#define ZYNQ_QSPI_LCFG_DUMMY_SHIFT 8 105 106#define ZYNQ_QSPI_FAST_READ_QOUT_CODE 0x6B /* read instruction code */ 107#define ZYNQ_QSPI_FIFO_DEPTH 63 /* FIFO depth in words */ 108#define ZYNQ_QSPI_RX_THRESHOLD 32 /* Rx FIFO threshold level */ 109#define ZYNQ_QSPI_TX_THRESHOLD 1 /* Tx FIFO threshold level */ 110 111/* 112 * The modebits configurable by the driver to make the SPI support different 113 * data formats 114 */ 115#define ZYNQ_QSPI_MODEBITS (SPI_CPOL | SPI_CPHA) 116 117/* Maximum number of chip selects */ 118#define ZYNQ_QSPI_MAX_NUM_CS 2 119 120/** 121 * struct zynq_qspi - Defines qspi driver instance 122 * @dev: Pointer to the this device's information 123 * @regs: Virtual address of the QSPI controller registers 124 * @refclk: Pointer to the peripheral clock 125 * @pclk: Pointer to the APB clock 126 * @irq: IRQ number 127 * @txbuf: Pointer to the TX buffer 128 * @rxbuf: Pointer to the RX buffer 129 * @tx_bytes: Number of bytes left to transfer 130 * @rx_bytes: Number of bytes left to receive 131 * @data_completion: completion structure 132 */ 133struct zynq_qspi { 134 struct device *dev; 135 void __iomem *regs; 136 struct clk *refclk; 137 struct clk *pclk; 138 int irq; 139 u8 *txbuf; 140 u8 *rxbuf; 141 int tx_bytes; 142 int rx_bytes; 143 struct completion data_completion; 144}; 145 146/* 147 * Inline functions for the QSPI controller read/write 148 */ 149static inline u32 zynq_qspi_read(struct zynq_qspi *xqspi, u32 offset) 150{ 151 return readl_relaxed(xqspi->regs + offset); 152} 153 154static inline void zynq_qspi_write(struct zynq_qspi *xqspi, u32 offset, 155 u32 val) 156{ 157 writel_relaxed(val, xqspi->regs + offset); 158} 159 160/** 161 * zynq_qspi_init_hw - Initialize the hardware 162 * @xqspi: Pointer to the zynq_qspi structure 163 * @num_cs: Number of connected CS (to enable dual memories if needed) 164 * 165 * The default settings of the QSPI controller's configurable parameters on 166 * reset are 167 * - Host mode 168 * - Baud rate divisor is set to 2 169 * - Tx threshold set to 1l Rx threshold set to 32 170 * - Flash memory interface mode enabled 171 * - Size of the word to be transferred as 8 bit 172 * This function performs the following actions 173 * - Disable and clear all the interrupts 174 * - Enable manual target select 175 * - Enable manual start 176 * - Deselect all the chip select lines 177 * - Set the size of the word to be transferred as 32 bit 178 * - Set the little endian mode of TX FIFO and 179 * - Enable the QSPI controller 180 */ 181static void zynq_qspi_init_hw(struct zynq_qspi *xqspi, unsigned int num_cs) 182{ 183 u32 config_reg; 184 185 zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, 0); 186 zynq_qspi_write(xqspi, ZYNQ_QSPI_IDIS_OFFSET, ZYNQ_QSPI_IXR_ALL_MASK); 187 188 /* Disable linear mode as the boot loader may have used it */ 189 config_reg = 0; 190 /* At the same time, enable dual mode if more than 1 CS is available */ 191 if (num_cs > 1) 192 config_reg |= ZYNQ_QSPI_LCFG_TWO_MEM; 193 194 zynq_qspi_write(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET, config_reg); 195 196 /* Clear the RX FIFO */ 197 while (zynq_qspi_read(xqspi, ZYNQ_QSPI_STATUS_OFFSET) & 198 ZYNQ_QSPI_IXR_RXNEMTY_MASK) 199 zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET); 200 201 zynq_qspi_write(xqspi, ZYNQ_QSPI_STATUS_OFFSET, ZYNQ_QSPI_IXR_ALL_MASK); 202 config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET); 203 config_reg &= ~(ZYNQ_QSPI_CONFIG_MSTREN_MASK | 204 ZYNQ_QSPI_CONFIG_CPOL_MASK | 205 ZYNQ_QSPI_CONFIG_CPHA_MASK | 206 ZYNQ_QSPI_CONFIG_BDRATE_MASK | 207 ZYNQ_QSPI_CONFIG_SSFORCE_MASK | 208 ZYNQ_QSPI_CONFIG_MANSRTEN_MASK | 209 ZYNQ_QSPI_CONFIG_MANSRT_MASK); 210 config_reg |= (ZYNQ_QSPI_CONFIG_MSTREN_MASK | 211 ZYNQ_QSPI_CONFIG_SSFORCE_MASK | 212 ZYNQ_QSPI_CONFIG_FWIDTH_MASK | 213 ZYNQ_QSPI_CONFIG_IFMODE_MASK); 214 zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg); 215 216 zynq_qspi_write(xqspi, ZYNQ_QSPI_RX_THRESH_OFFSET, 217 ZYNQ_QSPI_RX_THRESHOLD); 218 zynq_qspi_write(xqspi, ZYNQ_QSPI_TX_THRESH_OFFSET, 219 ZYNQ_QSPI_TX_THRESHOLD); 220 221 zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, 222 ZYNQ_QSPI_ENABLE_ENABLE_MASK); 223} 224 225static bool zynq_qspi_supports_op(struct spi_mem *mem, 226 const struct spi_mem_op *op) 227{ 228 if (!spi_mem_default_supports_op(mem, op)) 229 return false; 230 231 /* 232 * The number of address bytes should be equal to or less than 3 bytes. 233 */ 234 if (op->addr.nbytes > 3) 235 return false; 236 237 return true; 238} 239 240/** 241 * zynq_qspi_rxfifo_op - Read 1..4 bytes from RxFIFO to RX buffer 242 * @xqspi: Pointer to the zynq_qspi structure 243 * @size: Number of bytes to be read (1..4) 244 */ 245static void zynq_qspi_rxfifo_op(struct zynq_qspi *xqspi, unsigned int size) 246{ 247 u32 data; 248 249 data = zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET); 250 251 if (xqspi->rxbuf) { 252 memcpy(xqspi->rxbuf, ((u8 *)&data) + 4 - size, size); 253 xqspi->rxbuf += size; 254 } 255 256 xqspi->rx_bytes -= size; 257 if (xqspi->rx_bytes < 0) 258 xqspi->rx_bytes = 0; 259} 260 261/** 262 * zynq_qspi_txfifo_op - Write 1..4 bytes from TX buffer to TxFIFO 263 * @xqspi: Pointer to the zynq_qspi structure 264 * @size: Number of bytes to be written (1..4) 265 */ 266static void zynq_qspi_txfifo_op(struct zynq_qspi *xqspi, unsigned int size) 267{ 268 static const unsigned int offset[4] = { 269 ZYNQ_QSPI_TXD_00_01_OFFSET, ZYNQ_QSPI_TXD_00_10_OFFSET, 270 ZYNQ_QSPI_TXD_00_11_OFFSET, ZYNQ_QSPI_TXD_00_00_OFFSET }; 271 u32 data; 272 273 if (xqspi->txbuf) { 274 data = 0xffffffff; 275 memcpy(&data, xqspi->txbuf, size); 276 xqspi->txbuf += size; 277 } else { 278 data = 0; 279 } 280 281 xqspi->tx_bytes -= size; 282 zynq_qspi_write(xqspi, offset[size - 1], data); 283} 284 285/** 286 * zynq_qspi_chipselect - Select or deselect the chip select line 287 * @spi: Pointer to the spi_device structure 288 * @assert: 1 for select or 0 for deselect the chip select line 289 */ 290static void zynq_qspi_chipselect(struct spi_device *spi, bool assert) 291{ 292 struct spi_controller *ctlr = spi->controller; 293 struct zynq_qspi *xqspi = spi_controller_get_devdata(ctlr); 294 u32 config_reg; 295 296 /* Select the lower (CS0) or upper (CS1) memory */ 297 if (ctlr->num_chipselect > 1) { 298 config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET); 299 if (!spi_get_chipselect(spi, 0)) 300 config_reg &= ~ZYNQ_QSPI_LCFG_U_PAGE; 301 else 302 config_reg |= ZYNQ_QSPI_LCFG_U_PAGE; 303 304 zynq_qspi_write(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET, config_reg); 305 } 306 307 /* Ground the line to assert the CS */ 308 config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET); 309 if (assert) 310 config_reg &= ~ZYNQ_QSPI_CONFIG_PCS; 311 else 312 config_reg |= ZYNQ_QSPI_CONFIG_PCS; 313 314 zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg); 315} 316 317/** 318 * zynq_qspi_config_op - Configure QSPI controller for specified transfer 319 * @xqspi: Pointer to the zynq_qspi structure 320 * @spi: Pointer to the spi_device structure 321 * 322 * Sets the operational mode of QSPI controller for the next QSPI transfer and 323 * sets the requested clock frequency. 324 * 325 * Return: 0 on success and -EINVAL on invalid input parameter 326 * 327 * Note: If the requested frequency is not an exact match with what can be 328 * obtained using the prescalar value, the driver sets the clock frequency which 329 * is lower than the requested frequency (maximum lower) for the transfer. If 330 * the requested frequency is higher or lower than that is supported by the QSPI 331 * controller the driver will set the highest or lowest frequency supported by 332 * controller. 333 */ 334static int zynq_qspi_config_op(struct zynq_qspi *xqspi, struct spi_device *spi) 335{ 336 u32 config_reg, baud_rate_val = 0; 337 338 /* 339 * Set the clock frequency 340 * The baud rate divisor is not a direct mapping to the value written 341 * into the configuration register (config_reg[5:3]) 342 * i.e. 000 - divide by 2 343 * 001 - divide by 4 344 * ---------------- 345 * 111 - divide by 256 346 */ 347 while ((baud_rate_val < ZYNQ_QSPI_CONFIG_BAUD_DIV_MAX) && 348 (clk_get_rate(xqspi->refclk) / (2 << baud_rate_val)) > 349 spi->max_speed_hz) 350 baud_rate_val++; 351 352 config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET); 353 354 /* Set the QSPI clock phase and clock polarity */ 355 config_reg &= (~ZYNQ_QSPI_CONFIG_CPHA_MASK) & 356 (~ZYNQ_QSPI_CONFIG_CPOL_MASK); 357 if (spi->mode & SPI_CPHA) 358 config_reg |= ZYNQ_QSPI_CONFIG_CPHA_MASK; 359 if (spi->mode & SPI_CPOL) 360 config_reg |= ZYNQ_QSPI_CONFIG_CPOL_MASK; 361 362 config_reg &= ~ZYNQ_QSPI_CONFIG_BDRATE_MASK; 363 config_reg |= (baud_rate_val << ZYNQ_QSPI_CONFIG_BAUD_DIV_SHIFT); 364 zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg); 365 366 return 0; 367} 368 369/** 370 * zynq_qspi_setup_op - Configure the QSPI controller 371 * @spi: Pointer to the spi_device structure 372 * 373 * Sets the operational mode of QSPI controller for the next QSPI transfer, baud 374 * rate and divisor value to setup the requested qspi clock. 375 * 376 * Return: 0 on success and error value on failure 377 */ 378static int zynq_qspi_setup_op(struct spi_device *spi) 379{ 380 struct spi_controller *ctlr = spi->controller; 381 struct zynq_qspi *qspi = spi_controller_get_devdata(ctlr); 382 383 if (ctlr->busy) 384 return -EBUSY; 385 386 clk_enable(qspi->refclk); 387 clk_enable(qspi->pclk); 388 zynq_qspi_write(qspi, ZYNQ_QSPI_ENABLE_OFFSET, 389 ZYNQ_QSPI_ENABLE_ENABLE_MASK); 390 391 return 0; 392} 393 394/** 395 * zynq_qspi_write_op - Fills the TX FIFO with as many bytes as possible 396 * @xqspi: Pointer to the zynq_qspi structure 397 * @txcount: Maximum number of words to write 398 * @txempty: Indicates that TxFIFO is empty 399 */ 400static void zynq_qspi_write_op(struct zynq_qspi *xqspi, int txcount, 401 bool txempty) 402{ 403 int count, len, k; 404 405 len = xqspi->tx_bytes; 406 if (len && len < 4) { 407 /* 408 * We must empty the TxFIFO between accesses to TXD0, 409 * TXD1, TXD2, TXD3. 410 */ 411 if (txempty) 412 zynq_qspi_txfifo_op(xqspi, len); 413 414 return; 415 } 416 417 count = len / 4; 418 if (count > txcount) 419 count = txcount; 420 421 if (xqspi->txbuf) { 422 iowrite32_rep(xqspi->regs + ZYNQ_QSPI_TXD_00_00_OFFSET, 423 xqspi->txbuf, count); 424 xqspi->txbuf += count * 4; 425 } else { 426 for (k = 0; k < count; k++) 427 writel_relaxed(0, xqspi->regs + 428 ZYNQ_QSPI_TXD_00_00_OFFSET); 429 } 430 431 xqspi->tx_bytes -= count * 4; 432} 433 434/** 435 * zynq_qspi_read_op - Drains the RX FIFO by as many bytes as possible 436 * @xqspi: Pointer to the zynq_qspi structure 437 * @rxcount: Maximum number of words to read 438 */ 439static void zynq_qspi_read_op(struct zynq_qspi *xqspi, int rxcount) 440{ 441 int count, len, k; 442 443 len = xqspi->rx_bytes - xqspi->tx_bytes; 444 count = len / 4; 445 if (count > rxcount) 446 count = rxcount; 447 if (xqspi->rxbuf) { 448 ioread32_rep(xqspi->regs + ZYNQ_QSPI_RXD_OFFSET, 449 xqspi->rxbuf, count); 450 xqspi->rxbuf += count * 4; 451 } else { 452 for (k = 0; k < count; k++) 453 readl_relaxed(xqspi->regs + ZYNQ_QSPI_RXD_OFFSET); 454 } 455 xqspi->rx_bytes -= count * 4; 456 len -= count * 4; 457 458 if (len && len < 4 && count < rxcount) 459 zynq_qspi_rxfifo_op(xqspi, len); 460} 461 462/** 463 * zynq_qspi_irq - Interrupt service routine of the QSPI controller 464 * @irq: IRQ number 465 * @dev_id: Pointer to the xqspi structure 466 * 467 * This function handles TX empty only. 468 * On TX empty interrupt this function reads the received data from RX FIFO and 469 * fills the TX FIFO if there is any data remaining to be transferred. 470 * 471 * Return: IRQ_HANDLED when interrupt is handled; IRQ_NONE otherwise. 472 */ 473static irqreturn_t zynq_qspi_irq(int irq, void *dev_id) 474{ 475 u32 intr_status; 476 bool txempty; 477 struct zynq_qspi *xqspi = (struct zynq_qspi *)dev_id; 478 479 intr_status = zynq_qspi_read(xqspi, ZYNQ_QSPI_STATUS_OFFSET); 480 zynq_qspi_write(xqspi, ZYNQ_QSPI_STATUS_OFFSET, intr_status); 481 482 if ((intr_status & ZYNQ_QSPI_IXR_TXNFULL_MASK) || 483 (intr_status & ZYNQ_QSPI_IXR_RXNEMTY_MASK)) { 484 /* 485 * This bit is set when Tx FIFO has < THRESHOLD entries. 486 * We have the THRESHOLD value set to 1, 487 * so this bit indicates Tx FIFO is empty. 488 */ 489 txempty = !!(intr_status & ZYNQ_QSPI_IXR_TXNFULL_MASK); 490 /* Read out the data from the RX FIFO */ 491 zynq_qspi_read_op(xqspi, ZYNQ_QSPI_RX_THRESHOLD); 492 if (xqspi->tx_bytes) { 493 /* There is more data to send */ 494 zynq_qspi_write_op(xqspi, ZYNQ_QSPI_RX_THRESHOLD, 495 txempty); 496 } else { 497 /* 498 * If transfer and receive is completed then only send 499 * complete signal. 500 */ 501 if (!xqspi->rx_bytes) { 502 zynq_qspi_write(xqspi, 503 ZYNQ_QSPI_IDIS_OFFSET, 504 ZYNQ_QSPI_IXR_RXTX_MASK); 505 complete(&xqspi->data_completion); 506 } 507 } 508 return IRQ_HANDLED; 509 } 510 511 return IRQ_NONE; 512} 513 514/** 515 * zynq_qspi_exec_mem_op() - Initiates the QSPI transfer 516 * @mem: the SPI memory 517 * @op: the memory operation to execute 518 * 519 * Executes a memory operation. 520 * 521 * This function first selects the chip and starts the memory operation. 522 * 523 * Return: 0 in case of success, a negative error code otherwise. 524 */ 525static int zynq_qspi_exec_mem_op(struct spi_mem *mem, 526 const struct spi_mem_op *op) 527{ 528 struct zynq_qspi *xqspi = spi_controller_get_devdata(mem->spi->controller); 529 int err = 0, i; 530 u8 *tmpbuf; 531 532 dev_dbg(xqspi->dev, "cmd:%#x mode:%d.%d.%d.%d\n", 533 op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, 534 op->dummy.buswidth, op->data.buswidth); 535 536 zynq_qspi_chipselect(mem->spi, true); 537 zynq_qspi_config_op(xqspi, mem->spi); 538 539 if (op->cmd.opcode) { 540 reinit_completion(&xqspi->data_completion); 541 xqspi->txbuf = (u8 *)&op->cmd.opcode; 542 xqspi->rxbuf = NULL; 543 xqspi->tx_bytes = op->cmd.nbytes; 544 xqspi->rx_bytes = op->cmd.nbytes; 545 zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); 546 zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET, 547 ZYNQ_QSPI_IXR_RXTX_MASK); 548 if (!wait_for_completion_timeout(&xqspi->data_completion, 549 msecs_to_jiffies(1000))) 550 err = -ETIMEDOUT; 551 } 552 553 if (op->addr.nbytes) { 554 for (i = 0; i < op->addr.nbytes; i++) { 555 xqspi->txbuf[i] = op->addr.val >> 556 (8 * (op->addr.nbytes - i - 1)); 557 } 558 559 reinit_completion(&xqspi->data_completion); 560 xqspi->rxbuf = NULL; 561 xqspi->tx_bytes = op->addr.nbytes; 562 xqspi->rx_bytes = op->addr.nbytes; 563 zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); 564 zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET, 565 ZYNQ_QSPI_IXR_RXTX_MASK); 566 if (!wait_for_completion_timeout(&xqspi->data_completion, 567 msecs_to_jiffies(1000))) 568 err = -ETIMEDOUT; 569 } 570 571 if (op->dummy.nbytes) { 572 tmpbuf = kzalloc(op->dummy.nbytes, GFP_KERNEL); 573 if (!tmpbuf) 574 return -ENOMEM; 575 576 memset(tmpbuf, 0xff, op->dummy.nbytes); 577 reinit_completion(&xqspi->data_completion); 578 xqspi->txbuf = tmpbuf; 579 xqspi->rxbuf = NULL; 580 xqspi->tx_bytes = op->dummy.nbytes; 581 xqspi->rx_bytes = op->dummy.nbytes; 582 zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); 583 zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET, 584 ZYNQ_QSPI_IXR_RXTX_MASK); 585 if (!wait_for_completion_timeout(&xqspi->data_completion, 586 msecs_to_jiffies(1000))) 587 err = -ETIMEDOUT; 588 589 kfree(tmpbuf); 590 } 591 592 if (op->data.nbytes) { 593 reinit_completion(&xqspi->data_completion); 594 if (op->data.dir == SPI_MEM_DATA_OUT) { 595 xqspi->txbuf = (u8 *)op->data.buf.out; 596 xqspi->tx_bytes = op->data.nbytes; 597 xqspi->rxbuf = NULL; 598 xqspi->rx_bytes = op->data.nbytes; 599 } else { 600 xqspi->txbuf = NULL; 601 xqspi->rxbuf = (u8 *)op->data.buf.in; 602 xqspi->rx_bytes = op->data.nbytes; 603 xqspi->tx_bytes = op->data.nbytes; 604 } 605 606 zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); 607 zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET, 608 ZYNQ_QSPI_IXR_RXTX_MASK); 609 if (!wait_for_completion_timeout(&xqspi->data_completion, 610 msecs_to_jiffies(1000))) 611 err = -ETIMEDOUT; 612 } 613 zynq_qspi_chipselect(mem->spi, false); 614 615 return err; 616} 617 618static const struct spi_controller_mem_ops zynq_qspi_mem_ops = { 619 .supports_op = zynq_qspi_supports_op, 620 .exec_op = zynq_qspi_exec_mem_op, 621}; 622 623/** 624 * zynq_qspi_probe - Probe method for the QSPI driver 625 * @pdev: Pointer to the platform_device structure 626 * 627 * This function initializes the driver data structures and the hardware. 628 * 629 * Return: 0 on success and error value on failure 630 */ 631static int zynq_qspi_probe(struct platform_device *pdev) 632{ 633 int ret = 0; 634 struct spi_controller *ctlr; 635 struct device *dev = &pdev->dev; 636 struct device_node *np = dev->of_node; 637 struct zynq_qspi *xqspi; 638 u32 num_cs; 639 640 ctlr = spi_alloc_host(&pdev->dev, sizeof(*xqspi)); 641 if (!ctlr) 642 return -ENOMEM; 643 644 xqspi = spi_controller_get_devdata(ctlr); 645 xqspi->dev = dev; 646 platform_set_drvdata(pdev, xqspi); 647 xqspi->regs = devm_platform_ioremap_resource(pdev, 0); 648 if (IS_ERR(xqspi->regs)) { 649 ret = PTR_ERR(xqspi->regs); 650 goto remove_ctlr; 651 } 652 653 xqspi->pclk = devm_clk_get(&pdev->dev, "pclk"); 654 if (IS_ERR(xqspi->pclk)) { 655 dev_err(&pdev->dev, "pclk clock not found.\n"); 656 ret = PTR_ERR(xqspi->pclk); 657 goto remove_ctlr; 658 } 659 660 init_completion(&xqspi->data_completion); 661 662 xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk"); 663 if (IS_ERR(xqspi->refclk)) { 664 dev_err(&pdev->dev, "ref_clk clock not found.\n"); 665 ret = PTR_ERR(xqspi->refclk); 666 goto remove_ctlr; 667 } 668 669 ret = clk_prepare_enable(xqspi->pclk); 670 if (ret) { 671 dev_err(&pdev->dev, "Unable to enable APB clock.\n"); 672 goto remove_ctlr; 673 } 674 675 ret = clk_prepare_enable(xqspi->refclk); 676 if (ret) { 677 dev_err(&pdev->dev, "Unable to enable device clock.\n"); 678 goto clk_dis_pclk; 679 } 680 681 xqspi->irq = platform_get_irq(pdev, 0); 682 if (xqspi->irq < 0) { 683 ret = xqspi->irq; 684 goto clk_dis_all; 685 } 686 ret = devm_request_irq(&pdev->dev, xqspi->irq, zynq_qspi_irq, 687 0, pdev->name, xqspi); 688 if (ret != 0) { 689 ret = -ENXIO; 690 dev_err(&pdev->dev, "request_irq failed\n"); 691 goto clk_dis_all; 692 } 693 694 ret = of_property_read_u32(np, "num-cs", 695 &num_cs); 696 if (ret < 0) { 697 ctlr->num_chipselect = 1; 698 } else if (num_cs > ZYNQ_QSPI_MAX_NUM_CS) { 699 ret = -EINVAL; 700 dev_err(&pdev->dev, "only 2 chip selects are available\n"); 701 goto clk_dis_all; 702 } else { 703 ctlr->num_chipselect = num_cs; 704 } 705 706 ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | 707 SPI_TX_DUAL | SPI_TX_QUAD; 708 ctlr->mem_ops = &zynq_qspi_mem_ops; 709 ctlr->setup = zynq_qspi_setup_op; 710 ctlr->max_speed_hz = clk_get_rate(xqspi->refclk) / 2; 711 ctlr->dev.of_node = np; 712 713 /* QSPI controller initializations */ 714 zynq_qspi_init_hw(xqspi, ctlr->num_chipselect); 715 716 ret = devm_spi_register_controller(&pdev->dev, ctlr); 717 if (ret) { 718 dev_err(&pdev->dev, "devm_spi_register_controller failed\n"); 719 goto clk_dis_all; 720 } 721 722 return ret; 723 724clk_dis_all: 725 clk_disable_unprepare(xqspi->refclk); 726clk_dis_pclk: 727 clk_disable_unprepare(xqspi->pclk); 728remove_ctlr: 729 spi_controller_put(ctlr); 730 731 return ret; 732} 733 734/** 735 * zynq_qspi_remove - Remove method for the QSPI driver 736 * @pdev: Pointer to the platform_device structure 737 * 738 * This function is called if a device is physically removed from the system or 739 * if the driver module is being unloaded. It frees all resources allocated to 740 * the device. 741 * 742 * Return: 0 on success and error value on failure 743 */ 744static void zynq_qspi_remove(struct platform_device *pdev) 745{ 746 struct zynq_qspi *xqspi = platform_get_drvdata(pdev); 747 748 zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, 0); 749 750 clk_disable_unprepare(xqspi->refclk); 751 clk_disable_unprepare(xqspi->pclk); 752} 753 754static const struct of_device_id zynq_qspi_of_match[] = { 755 { .compatible = "xlnx,zynq-qspi-1.0", }, 756 { /* end of table */ } 757}; 758 759MODULE_DEVICE_TABLE(of, zynq_qspi_of_match); 760 761/* 762 * zynq_qspi_driver - This structure defines the QSPI platform driver 763 */ 764static struct platform_driver zynq_qspi_driver = { 765 .probe = zynq_qspi_probe, 766 .remove_new = zynq_qspi_remove, 767 .driver = { 768 .name = "zynq-qspi", 769 .of_match_table = zynq_qspi_of_match, 770 }, 771}; 772 773module_platform_driver(zynq_qspi_driver); 774 775MODULE_AUTHOR("Xilinx, Inc."); 776MODULE_DESCRIPTION("Xilinx Zynq QSPI driver"); 777MODULE_LICENSE("GPL"); 778