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   1/*
   2 * Xilinx Zynq UltraScale+ MPSoC Quad-SPI (QSPI) controller driver
   3 * (master mode only)
   4 *
   5 * Copyright (C) 2009 - 2015 Xilinx, Inc.
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of the GNU General Public License version 2 as published
   9 * by the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 */
  12
  13#include <linux/clk.h>
  14#include <linux/delay.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/dmaengine.h>
  17#include <linux/interrupt.h>
  18#include <linux/io.h>
  19#include <linux/module.h>
  20#include <linux/of_irq.h>
  21#include <linux/of_address.h>
  22#include <linux/platform_device.h>
  23#include <linux/spi/spi.h>
  24#include <linux/spinlock.h>
  25#include <linux/workqueue.h>
  26
  27/* Generic QSPI register offsets */
  28#define GQSPI_CONFIG_OFST		0x00000100
  29#define GQSPI_ISR_OFST			0x00000104
  30#define GQSPI_IDR_OFST			0x0000010C
  31#define GQSPI_IER_OFST			0x00000108
  32#define GQSPI_IMASK_OFST		0x00000110
  33#define GQSPI_EN_OFST			0x00000114
  34#define GQSPI_TXD_OFST			0x0000011C
  35#define GQSPI_RXD_OFST			0x00000120
  36#define GQSPI_TX_THRESHOLD_OFST		0x00000128
  37#define GQSPI_RX_THRESHOLD_OFST		0x0000012C
  38#define GQSPI_LPBK_DLY_ADJ_OFST		0x00000138
  39#define GQSPI_GEN_FIFO_OFST		0x00000140
  40#define GQSPI_SEL_OFST			0x00000144
  41#define GQSPI_GF_THRESHOLD_OFST		0x00000150
  42#define GQSPI_FIFO_CTRL_OFST		0x0000014C
  43#define GQSPI_QSPIDMA_DST_CTRL_OFST	0x0000080C
  44#define GQSPI_QSPIDMA_DST_SIZE_OFST	0x00000804
  45#define GQSPI_QSPIDMA_DST_STS_OFST	0x00000808
  46#define GQSPI_QSPIDMA_DST_I_STS_OFST	0x00000814
  47#define GQSPI_QSPIDMA_DST_I_EN_OFST	0x00000818
  48#define GQSPI_QSPIDMA_DST_I_DIS_OFST	0x0000081C
  49#define GQSPI_QSPIDMA_DST_I_MASK_OFST	0x00000820
  50#define GQSPI_QSPIDMA_DST_ADDR_OFST	0x00000800
  51#define GQSPI_QSPIDMA_DST_ADDR_MSB_OFST 0x00000828
  52
  53/* GQSPI register bit masks */
  54#define GQSPI_SEL_MASK				0x00000001
  55#define GQSPI_EN_MASK				0x00000001
  56#define GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK	0x00000020
  57#define GQSPI_ISR_WR_TO_CLR_MASK		0x00000002
  58#define GQSPI_IDR_ALL_MASK			0x00000FBE
  59#define GQSPI_CFG_MODE_EN_MASK			0xC0000000
  60#define GQSPI_CFG_GEN_FIFO_START_MODE_MASK	0x20000000
  61#define GQSPI_CFG_ENDIAN_MASK			0x04000000
  62#define GQSPI_CFG_EN_POLL_TO_MASK		0x00100000
  63#define GQSPI_CFG_WP_HOLD_MASK			0x00080000
  64#define GQSPI_CFG_BAUD_RATE_DIV_MASK		0x00000038
  65#define GQSPI_CFG_CLK_PHA_MASK			0x00000004
  66#define GQSPI_CFG_CLK_POL_MASK			0x00000002
  67#define GQSPI_CFG_START_GEN_FIFO_MASK		0x10000000
  68#define GQSPI_GENFIFO_IMM_DATA_MASK		0x000000FF
  69#define GQSPI_GENFIFO_DATA_XFER			0x00000100
  70#define GQSPI_GENFIFO_EXP			0x00000200
  71#define GQSPI_GENFIFO_MODE_SPI			0x00000400
  72#define GQSPI_GENFIFO_MODE_DUALSPI		0x00000800
  73#define GQSPI_GENFIFO_MODE_QUADSPI		0x00000C00
  74#define GQSPI_GENFIFO_MODE_MASK			0x00000C00
  75#define GQSPI_GENFIFO_CS_LOWER			0x00001000
  76#define GQSPI_GENFIFO_CS_UPPER			0x00002000
  77#define GQSPI_GENFIFO_BUS_LOWER			0x00004000
  78#define GQSPI_GENFIFO_BUS_UPPER			0x00008000
  79#define GQSPI_GENFIFO_BUS_BOTH			0x0000C000
  80#define GQSPI_GENFIFO_BUS_MASK			0x0000C000
  81#define GQSPI_GENFIFO_TX			0x00010000
  82#define GQSPI_GENFIFO_RX			0x00020000
  83#define GQSPI_GENFIFO_STRIPE			0x00040000
  84#define GQSPI_GENFIFO_POLL			0x00080000
  85#define GQSPI_GENFIFO_EXP_START			0x00000100
  86#define GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK	0x00000004
  87#define GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK	0x00000002
  88#define GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK	0x00000001
  89#define GQSPI_ISR_RXEMPTY_MASK			0x00000800
  90#define GQSPI_ISR_GENFIFOFULL_MASK		0x00000400
  91#define GQSPI_ISR_GENFIFONOT_FULL_MASK		0x00000200
  92#define GQSPI_ISR_TXEMPTY_MASK			0x00000100
  93#define GQSPI_ISR_GENFIFOEMPTY_MASK		0x00000080
  94#define GQSPI_ISR_RXFULL_MASK			0x00000020
  95#define GQSPI_ISR_RXNEMPTY_MASK			0x00000010
  96#define GQSPI_ISR_TXFULL_MASK			0x00000008
  97#define GQSPI_ISR_TXNOT_FULL_MASK		0x00000004
  98#define GQSPI_ISR_POLL_TIME_EXPIRE_MASK		0x00000002
  99#define GQSPI_IER_TXNOT_FULL_MASK		0x00000004
 100#define GQSPI_IER_RXEMPTY_MASK			0x00000800
 101#define GQSPI_IER_POLL_TIME_EXPIRE_MASK		0x00000002
 102#define GQSPI_IER_RXNEMPTY_MASK			0x00000010
 103#define GQSPI_IER_GENFIFOEMPTY_MASK		0x00000080
 104#define GQSPI_IER_TXEMPTY_MASK			0x00000100
 105#define GQSPI_QSPIDMA_DST_INTR_ALL_MASK		0x000000FE
 106#define GQSPI_QSPIDMA_DST_STS_WTC		0x0000E000
 107#define GQSPI_CFG_MODE_EN_DMA_MASK		0x80000000
 108#define GQSPI_ISR_IDR_MASK			0x00000994
 109#define GQSPI_QSPIDMA_DST_I_EN_DONE_MASK	0x00000002
 110#define GQSPI_QSPIDMA_DST_I_STS_DONE_MASK	0x00000002
 111#define GQSPI_IRQ_MASK				0x00000980
 112
 113#define GQSPI_CFG_BAUD_RATE_DIV_SHIFT		3
 114#define GQSPI_GENFIFO_CS_SETUP			0x4
 115#define GQSPI_GENFIFO_CS_HOLD			0x3
 116#define GQSPI_TXD_DEPTH				64
 117#define GQSPI_RX_FIFO_THRESHOLD			32
 118#define GQSPI_RX_FIFO_FILL	(GQSPI_RX_FIFO_THRESHOLD * 4)
 119#define GQSPI_TX_FIFO_THRESHOLD_RESET_VAL	32
 120#define GQSPI_TX_FIFO_FILL	(GQSPI_TXD_DEPTH -\
 121				GQSPI_TX_FIFO_THRESHOLD_RESET_VAL)
 122#define GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL	0X10
 123#define GQSPI_QSPIDMA_DST_CTRL_RESET_VAL	0x803FFA00
 124#define GQSPI_SELECT_FLASH_CS_LOWER		0x1
 125#define GQSPI_SELECT_FLASH_CS_UPPER		0x2
 126#define GQSPI_SELECT_FLASH_CS_BOTH		0x3
 127#define GQSPI_SELECT_FLASH_BUS_LOWER		0x1
 128#define GQSPI_SELECT_FLASH_BUS_UPPER		0x2
 129#define GQSPI_SELECT_FLASH_BUS_BOTH		0x3
 130#define GQSPI_BAUD_DIV_MAX	7	/* Baud rate divisor maximum */
 131#define GQSPI_BAUD_DIV_SHIFT	2	/* Baud rate divisor shift */
 132#define GQSPI_SELECT_MODE_SPI		0x1
 133#define GQSPI_SELECT_MODE_DUALSPI	0x2
 134#define GQSPI_SELECT_MODE_QUADSPI	0x4
 135#define GQSPI_DMA_UNALIGN		0x3
 136#define GQSPI_DEFAULT_NUM_CS	1	/* Default number of chip selects */
 137
 138enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
 139
 140/**
 141 * struct zynqmp_qspi - Defines qspi driver instance
 142 * @regs:		Virtual address of the QSPI controller registers
 143 * @refclk:		Pointer to the peripheral clock
 144 * @pclk:		Pointer to the APB clock
 145 * @irq:		IRQ number
 146 * @dev:		Pointer to struct device
 147 * @txbuf:		Pointer to the TX buffer
 148 * @rxbuf:		Pointer to the RX buffer
 149 * @bytes_to_transfer:	Number of bytes left to transfer
 150 * @bytes_to_receive:	Number of bytes left to receive
 151 * @genfifocs:		Used for chip select
 152 * @genfifobus:		Used to select the upper or lower bus
 153 * @dma_rx_bytes:	Remaining bytes to receive by DMA mode
 154 * @dma_addr:		DMA address after mapping the kernel buffer
 155 * @genfifoentry:	Used for storing the genfifoentry instruction.
 156 * @mode:		Defines the mode in which QSPI is operating
 157 */
 158struct zynqmp_qspi {
 159	void __iomem *regs;
 160	struct clk *refclk;
 161	struct clk *pclk;
 162	int irq;
 163	struct device *dev;
 164	const void *txbuf;
 165	void *rxbuf;
 166	int bytes_to_transfer;
 167	int bytes_to_receive;
 168	u32 genfifocs;
 169	u32 genfifobus;
 170	u32 dma_rx_bytes;
 171	dma_addr_t dma_addr;
 172	u32 genfifoentry;
 173	enum mode_type mode;
 174};
 175
 176/**
 177 * zynqmp_gqspi_read:	For GQSPI controller read operation
 178 * @xqspi:	Pointer to the zynqmp_qspi structure
 179 * @offset:	Offset from where to read
 180 */
 181static u32 zynqmp_gqspi_read(struct zynqmp_qspi *xqspi, u32 offset)
 182{
 183	return readl_relaxed(xqspi->regs + offset);
 184}
 185
 186/**
 187 * zynqmp_gqspi_write:	For GQSPI controller write operation
 188 * @xqspi:	Pointer to the zynqmp_qspi structure
 189 * @offset:	Offset where to write
 190 * @val:	Value to be written
 191 */
 192static inline void zynqmp_gqspi_write(struct zynqmp_qspi *xqspi, u32 offset,
 193				      u32 val)
 194{
 195	writel_relaxed(val, (xqspi->regs + offset));
 196}
 197
 198/**
 199 * zynqmp_gqspi_selectslave:	For selection of slave device
 200 * @instanceptr:	Pointer to the zynqmp_qspi structure
 201 * @flashcs:	For chip select
 202 * @flashbus:	To check which bus is selected- upper or lower
 203 */
 204static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
 205				     u8 slavecs, u8 slavebus)
 206{
 207	/*
 208	 * Bus and CS lines selected here will be updated in the instance and
 209	 * used for subsequent GENFIFO entries during transfer.
 210	 */
 211
 212	/* Choose slave select line */
 213	switch (slavecs) {
 214	case GQSPI_SELECT_FLASH_CS_BOTH:
 215		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER |
 216			GQSPI_GENFIFO_CS_UPPER;
 217		break;
 218	case GQSPI_SELECT_FLASH_CS_UPPER:
 219		instanceptr->genfifocs = GQSPI_GENFIFO_CS_UPPER;
 220		break;
 221	case GQSPI_SELECT_FLASH_CS_LOWER:
 222		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER;
 223		break;
 224	default:
 225		dev_warn(instanceptr->dev, "Invalid slave select\n");
 226	}
 227
 228	/* Choose the bus */
 229	switch (slavebus) {
 230	case GQSPI_SELECT_FLASH_BUS_BOTH:
 231		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER |
 232			GQSPI_GENFIFO_BUS_UPPER;
 233		break;
 234	case GQSPI_SELECT_FLASH_BUS_UPPER:
 235		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_UPPER;
 236		break;
 237	case GQSPI_SELECT_FLASH_BUS_LOWER:
 238		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER;
 239		break;
 240	default:
 241		dev_warn(instanceptr->dev, "Invalid slave bus\n");
 242	}
 243}
 244
 245/**
 246 * zynqmp_qspi_init_hw:	Initialize the hardware
 247 * @xqspi:	Pointer to the zynqmp_qspi structure
 248 *
 249 * The default settings of the QSPI controller's configurable parameters on
 250 * reset are
 251 *	- Master mode
 252 *	- TX threshold set to 1
 253 *	- RX threshold set to 1
 254 *	- Flash memory interface mode enabled
 255 * This function performs the following actions
 256 *	- Disable and clear all the interrupts
 257 *	- Enable manual slave select
 258 *	- Enable manual start
 259 *	- Deselect all the chip select lines
 260 *	- Set the little endian mode of TX FIFO and
 261 *	- Enable the QSPI controller
 262 */
 263static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
 264{
 265	u32 config_reg;
 266
 267	/* Select the GQSPI mode */
 268	zynqmp_gqspi_write(xqspi, GQSPI_SEL_OFST, GQSPI_SEL_MASK);
 269	/* Clear and disable interrupts */
 270	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST,
 271			   zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST) |
 272			   GQSPI_ISR_WR_TO_CLR_MASK);
 273	/* Clear the DMA STS */
 274	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
 275			   zynqmp_gqspi_read(xqspi,
 276					     GQSPI_QSPIDMA_DST_I_STS_OFST));
 277	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_STS_OFST,
 278			   zynqmp_gqspi_read(xqspi,
 279					     GQSPI_QSPIDMA_DST_STS_OFST) |
 280					     GQSPI_QSPIDMA_DST_STS_WTC);
 281	zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_IDR_ALL_MASK);
 282	zynqmp_gqspi_write(xqspi,
 283			   GQSPI_QSPIDMA_DST_I_DIS_OFST,
 284			   GQSPI_QSPIDMA_DST_INTR_ALL_MASK);
 285	/* Disable the GQSPI */
 286	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
 287	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
 288	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
 289	/* Manual start */
 290	config_reg |= GQSPI_CFG_GEN_FIFO_START_MODE_MASK;
 291	/* Little endian by default */
 292	config_reg &= ~GQSPI_CFG_ENDIAN_MASK;
 293	/* Disable poll time out */
 294	config_reg &= ~GQSPI_CFG_EN_POLL_TO_MASK;
 295	/* Set hold bit */
 296	config_reg |= GQSPI_CFG_WP_HOLD_MASK;
 297	/* Clear pre-scalar by default */
 298	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
 299	/* CPHA 0 */
 300	config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
 301	/* CPOL 0 */
 302	config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
 303	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
 304
 305	/* Clear the TX and RX FIFO */
 306	zynqmp_gqspi_write(xqspi, GQSPI_FIFO_CTRL_OFST,
 307			   GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK |
 308			   GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK |
 309			   GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK);
 310	/* Set by default to allow for high frequencies */
 311	zynqmp_gqspi_write(xqspi, GQSPI_LPBK_DLY_ADJ_OFST,
 312			   zynqmp_gqspi_read(xqspi, GQSPI_LPBK_DLY_ADJ_OFST) |
 313			   GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK);
 314	/* Reset thresholds */
 315	zynqmp_gqspi_write(xqspi, GQSPI_TX_THRESHOLD_OFST,
 316			   GQSPI_TX_FIFO_THRESHOLD_RESET_VAL);
 317	zynqmp_gqspi_write(xqspi, GQSPI_RX_THRESHOLD_OFST,
 318			   GQSPI_RX_FIFO_THRESHOLD);
 319	zynqmp_gqspi_write(xqspi, GQSPI_GF_THRESHOLD_OFST,
 320			   GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL);
 321	zynqmp_gqspi_selectslave(xqspi,
 322				 GQSPI_SELECT_FLASH_CS_LOWER,
 323				 GQSPI_SELECT_FLASH_BUS_LOWER);
 324	/* Initialize DMA */
 325	zynqmp_gqspi_write(xqspi,
 326			GQSPI_QSPIDMA_DST_CTRL_OFST,
 327			GQSPI_QSPIDMA_DST_CTRL_RESET_VAL);
 328
 329	/* Enable the GQSPI */
 330	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
 331}
 332
 333/**
 334 * zynqmp_qspi_copy_read_data:	Copy data to RX buffer
 335 * @xqspi:	Pointer to the zynqmp_qspi structure
 336 * @data:	The variable where data is stored
 337 * @size:	Number of bytes to be copied from data to RX buffer
 338 */
 339static void zynqmp_qspi_copy_read_data(struct zynqmp_qspi *xqspi,
 340				       ulong data, u8 size)
 341{
 342	memcpy(xqspi->rxbuf, &data, size);
 343	xqspi->rxbuf += size;
 344	xqspi->bytes_to_receive -= size;
 345}
 346
 347/**
 348 * zynqmp_prepare_transfer_hardware:	Prepares hardware for transfer.
 349 * @master:	Pointer to the spi_master structure which provides
 350 *		information about the controller.
 351 *
 352 * This function enables SPI master controller.
 353 *
 354 * Return:	0 on success; error value otherwise
 355 */
 356static int zynqmp_prepare_transfer_hardware(struct spi_master *master)
 357{
 358	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
 359	int ret;
 360
 361	ret = clk_enable(xqspi->refclk);
 362	if (ret)
 363		return ret;
 364
 365	ret = clk_enable(xqspi->pclk);
 366	if (ret)
 367		goto clk_err;
 368
 369	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
 370	return 0;
 371clk_err:
 372	clk_disable(xqspi->refclk);
 373	return ret;
 374}
 375
 376/**
 377 * zynqmp_unprepare_transfer_hardware:	Relaxes hardware after transfer
 378 * @master:	Pointer to the spi_master structure which provides
 379 *		information about the controller.
 380 *
 381 * This function disables the SPI master controller.
 382 *
 383 * Return:	Always 0
 384 */
 385static int zynqmp_unprepare_transfer_hardware(struct spi_master *master)
 386{
 387	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
 388
 389	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
 390	clk_disable(xqspi->refclk);
 391	clk_disable(xqspi->pclk);
 392	return 0;
 393}
 394
 395/**
 396 * zynqmp_qspi_chipselect:	Select or deselect the chip select line
 397 * @qspi:	Pointer to the spi_device structure
 398 * @is_high:	Select(0) or deselect (1) the chip select line
 399 */
 400static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high)
 401{
 402	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
 403	ulong timeout;
 404	u32 genfifoentry = 0x0, statusreg;
 405
 406	genfifoentry |= GQSPI_GENFIFO_MODE_SPI;
 407	genfifoentry |= xqspi->genfifobus;
 408
 409	if (!is_high) {
 410		genfifoentry |= xqspi->genfifocs;
 411		genfifoentry |= GQSPI_GENFIFO_CS_SETUP;
 412	} else {
 413		genfifoentry |= GQSPI_GENFIFO_CS_HOLD;
 414	}
 415
 416	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
 417
 418	/* Dummy generic FIFO entry */
 419	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
 420
 421	/* Manually start the generic FIFO command */
 422	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
 423			zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
 424			GQSPI_CFG_START_GEN_FIFO_MASK);
 425
 426	timeout = jiffies + msecs_to_jiffies(1000);
 427
 428	/* Wait until the generic FIFO command is empty */
 429	do {
 430		statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
 431
 432		if ((statusreg & GQSPI_ISR_GENFIFOEMPTY_MASK) &&
 433			(statusreg & GQSPI_ISR_TXEMPTY_MASK))
 434			break;
 435		else
 436			cpu_relax();
 437	} while (!time_after_eq(jiffies, timeout));
 438
 439	if (time_after_eq(jiffies, timeout))
 440		dev_err(xqspi->dev, "Chip select timed out\n");
 441}
 442
 443/**
 444 * zynqmp_qspi_setup_transfer:	Configure QSPI controller for specified
 445 *				transfer
 446 * @qspi:	Pointer to the spi_device structure
 447 * @transfer:	Pointer to the spi_transfer structure which provides
 448 *		information about next transfer setup parameters
 449 *
 450 * Sets the operational mode of QSPI controller for the next QSPI transfer and
 451 * sets the requested clock frequency.
 452 *
 453 * Return:	Always 0
 454 *
 455 * Note:
 456 *	If the requested frequency is not an exact match with what can be
 457 *	obtained using the pre-scalar value, the driver sets the clock
 458 *	frequency which is lower than the requested frequency (maximum lower)
 459 *	for the transfer.
 460 *
 461 *	If the requested frequency is higher or lower than that is supported
 462 *	by the QSPI controller the driver will set the highest or lowest
 463 *	frequency supported by controller.
 464 */
 465static int zynqmp_qspi_setup_transfer(struct spi_device *qspi,
 466				      struct spi_transfer *transfer)
 467{
 468	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
 469	ulong clk_rate;
 470	u32 config_reg, req_hz, baud_rate_val = 0;
 471
 472	if (transfer)
 473		req_hz = transfer->speed_hz;
 474	else
 475		req_hz = qspi->max_speed_hz;
 476
 477	/* Set the clock frequency */
 478	/* If req_hz == 0, default to lowest speed */
 479	clk_rate = clk_get_rate(xqspi->refclk);
 480
 481	while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
 482	       (clk_rate /
 483		(GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz)
 484		baud_rate_val++;
 485
 486	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
 487
 488	/* Set the QSPI clock phase and clock polarity */
 489	config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
 490
 491	if (qspi->mode & SPI_CPHA)
 492		config_reg |= GQSPI_CFG_CLK_PHA_MASK;
 493	if (qspi->mode & SPI_CPOL)
 494		config_reg |= GQSPI_CFG_CLK_POL_MASK;
 495
 496	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
 497	config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
 498	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
 499	return 0;
 500}
 501
 502/**
 503 * zynqmp_qspi_setup:	Configure the QSPI controller
 504 * @qspi:	Pointer to the spi_device structure
 505 *
 506 * Sets the operational mode of QSPI controller for the next QSPI transfer,
 507 * baud rate and divisor value to setup the requested qspi clock.
 508 *
 509 * Return:	0 on success; error value otherwise.
 510 */
 511static int zynqmp_qspi_setup(struct spi_device *qspi)
 512{
 513	if (qspi->master->busy)
 514		return -EBUSY;
 515	return 0;
 516}
 517
 518/**
 519 * zynqmp_qspi_filltxfifo:	Fills the TX FIFO as long as there is room in
 520 *				the FIFO or the bytes required to be
 521 *				transmitted.
 522 * @xqspi:	Pointer to the zynqmp_qspi structure
 523 * @size:	Number of bytes to be copied from TX buffer to TX FIFO
 524 */
 525static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
 526{
 527	u32 count = 0, intermediate;
 528
 529	while ((xqspi->bytes_to_transfer > 0) && (count < size)) {
 530		memcpy(&intermediate, xqspi->txbuf, 4);
 531		zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
 532
 533		if (xqspi->bytes_to_transfer >= 4) {
 534			xqspi->txbuf += 4;
 535			xqspi->bytes_to_transfer -= 4;
 536		} else {
 537			xqspi->txbuf += xqspi->bytes_to_transfer;
 538			xqspi->bytes_to_transfer = 0;
 539		}
 540		count++;
 541	}
 542}
 543
 544/**
 545 * zynqmp_qspi_readrxfifo:	Fills the RX FIFO as long as there is room in
 546 *				the FIFO.
 547 * @xqspi:	Pointer to the zynqmp_qspi structure
 548 * @size:	Number of bytes to be copied from RX buffer to RX FIFO
 549 */
 550static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
 551{
 552	ulong data;
 553	int count = 0;
 554
 555	while ((count < size) && (xqspi->bytes_to_receive > 0)) {
 556		if (xqspi->bytes_to_receive >= 4) {
 557			(*(u32 *) xqspi->rxbuf) =
 558			zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
 559			xqspi->rxbuf += 4;
 560			xqspi->bytes_to_receive -= 4;
 561			count += 4;
 562		} else {
 563			data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
 564			count += xqspi->bytes_to_receive;
 565			zynqmp_qspi_copy_read_data(xqspi, data,
 566						   xqspi->bytes_to_receive);
 567			xqspi->bytes_to_receive = 0;
 568		}
 569	}
 570}
 571
 572/**
 573 * zynqmp_process_dma_irq:	Handler for DMA done interrupt of QSPI
 574 *				controller
 575 * @xqspi:	zynqmp_qspi instance pointer
 576 *
 577 * This function handles DMA interrupt only.
 578 */
 579static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
 580{
 581	u32 config_reg, genfifoentry;
 582
 583	dma_unmap_single(xqspi->dev, xqspi->dma_addr,
 584				xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
 585	xqspi->rxbuf += xqspi->dma_rx_bytes;
 586	xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
 587	xqspi->dma_rx_bytes = 0;
 588
 589	/* Disabling the DMA interrupts */
 590	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST,
 591					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
 592
 593	if (xqspi->bytes_to_receive > 0) {
 594		/* Switch to IO mode,for remaining bytes to receive */
 595		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
 596		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
 597		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
 598
 599		/* Initiate the transfer of remaining bytes */
 600		genfifoentry = xqspi->genfifoentry;
 601		genfifoentry |= xqspi->bytes_to_receive;
 602		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
 603
 604		/* Dummy generic FIFO entry */
 605		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
 606
 607		/* Manual start */
 608		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
 609			(zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
 610			GQSPI_CFG_START_GEN_FIFO_MASK));
 611
 612		/* Enable the RX interrupts for IO mode */
 613		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
 614				GQSPI_IER_GENFIFOEMPTY_MASK |
 615				GQSPI_IER_RXNEMPTY_MASK |
 616				GQSPI_IER_RXEMPTY_MASK);
 617	}
 618}
 619
 620/**
 621 * zynqmp_qspi_irq:	Interrupt service routine of the QSPI controller
 622 * @irq:	IRQ number
 623 * @dev_id:	Pointer to the xqspi structure
 624 *
 625 * This function handles TX empty only.
 626 * On TX empty interrupt this function reads the received data from RX FIFO
 627 * and fills the TX FIFO if there is any data remaining to be transferred.
 628 *
 629 * Return:	IRQ_HANDLED when interrupt is handled
 630 *		IRQ_NONE otherwise.
 631 */
 632static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
 633{
 634	struct spi_master *master = dev_id;
 635	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
 636	int ret = IRQ_NONE;
 637	u32 status, mask, dma_status = 0;
 638
 639	status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
 640	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status);
 641	mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST)));
 642
 643	/* Read and clear DMA status */
 644	if (xqspi->mode == GQSPI_MODE_DMA) {
 645		dma_status =
 646			zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST);
 647		zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
 648								dma_status);
 649	}
 650
 651	if (mask & GQSPI_ISR_TXNOT_FULL_MASK) {
 652		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
 653		ret = IRQ_HANDLED;
 654	}
 655
 656	if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) {
 657		zynqmp_process_dma_irq(xqspi);
 658		ret = IRQ_HANDLED;
 659	} else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
 660			(mask & GQSPI_IER_GENFIFOEMPTY_MASK)) {
 661		zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
 662		ret = IRQ_HANDLED;
 663	}
 664
 665	if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0)
 666			&& ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
 667		zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK);
 668		spi_finalize_current_transfer(master);
 669		ret = IRQ_HANDLED;
 670	}
 671	return ret;
 672}
 673
 674/**
 675 * zynqmp_qspi_selectspimode:	Selects SPI mode - x1 or x2 or x4.
 676 * @xqspi:	xqspi is a pointer to the GQSPI instance
 677 * @spimode:	spimode - SPI or DUAL or QUAD.
 678 * Return:	Mask to set desired SPI mode in GENFIFO entry.
 679 */
 680static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi,
 681						u8 spimode)
 682{
 683	u32 mask = 0;
 684
 685	switch (spimode) {
 686	case GQSPI_SELECT_MODE_DUALSPI:
 687		mask = GQSPI_GENFIFO_MODE_DUALSPI;
 688		break;
 689	case GQSPI_SELECT_MODE_QUADSPI:
 690		mask = GQSPI_GENFIFO_MODE_QUADSPI;
 691		break;
 692	case GQSPI_SELECT_MODE_SPI:
 693		mask = GQSPI_GENFIFO_MODE_SPI;
 694		break;
 695	default:
 696		dev_warn(xqspi->dev, "Invalid SPI mode\n");
 697	}
 698
 699	return mask;
 700}
 701
 702/**
 703 * zynq_qspi_setuprxdma:	This function sets up the RX DMA operation
 704 * @xqspi:	xqspi is a pointer to the GQSPI instance.
 705 */
 706static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
 707{
 708	u32 rx_bytes, rx_rem, config_reg;
 709	dma_addr_t addr;
 710	u64 dma_align =  (u64)(uintptr_t)xqspi->rxbuf;
 711
 712	if ((xqspi->bytes_to_receive < 8) ||
 713		((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
 714		/* Setting to IO mode */
 715		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
 716		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
 717		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
 718		xqspi->mode = GQSPI_MODE_IO;
 719		xqspi->dma_rx_bytes = 0;
 720		return;
 721	}
 722
 723	rx_rem = xqspi->bytes_to_receive % 4;
 724	rx_bytes = (xqspi->bytes_to_receive - rx_rem);
 725
 726	addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
 727						rx_bytes, DMA_FROM_DEVICE);
 728	if (dma_mapping_error(xqspi->dev, addr))
 729		dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
 730
 731	xqspi->dma_rx_bytes = rx_bytes;
 732	xqspi->dma_addr = addr;
 733	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
 734				(u32)(addr & 0xffffffff));
 735	addr = ((addr >> 16) >> 16);
 736	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
 737				((u32)addr) & 0xfff);
 738
 739	/* Enabling the DMA mode */
 740	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
 741	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
 742	config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
 743	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
 744
 745	/* Switch to DMA mode */
 746	xqspi->mode = GQSPI_MODE_DMA;
 747
 748	/* Write the number of bytes to transfer */
 749	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
 750}
 751
 752/**
 753 * zynqmp_qspi_txrxsetup:	This function checks the TX/RX buffers in
 754 *				the transfer and sets up the GENFIFO entries,
 755 *				TX FIFO as required.
 756 * @xqspi:	xqspi is a pointer to the GQSPI instance.
 757 * @transfer:	It is a pointer to the structure containing transfer data.
 758 * @genfifoentry:	genfifoentry is pointer to the variable in which
 759 *			GENFIFO	mask is returned to calling function
 760 */
 761static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi,
 762				  struct spi_transfer *transfer,
 763				  u32 *genfifoentry)
 764{
 765	u32 config_reg;
 766
 767	/* Transmit */
 768	if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) {
 769		/* Setup data to be TXed */
 770		*genfifoentry &= ~GQSPI_GENFIFO_RX;
 771		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
 772		*genfifoentry |= GQSPI_GENFIFO_TX;
 773		*genfifoentry |=
 774			zynqmp_qspi_selectspimode(xqspi, transfer->tx_nbits);
 775		xqspi->bytes_to_transfer = transfer->len;
 776		if (xqspi->mode == GQSPI_MODE_DMA) {
 777			config_reg = zynqmp_gqspi_read(xqspi,
 778							GQSPI_CONFIG_OFST);
 779			config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
 780			zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
 781								config_reg);
 782			xqspi->mode = GQSPI_MODE_IO;
 783		}
 784		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
 785		/* Discard RX data */
 786		xqspi->bytes_to_receive = 0;
 787	} else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) {
 788		/* Receive */
 789
 790		/* TX auto fill */
 791		*genfifoentry &= ~GQSPI_GENFIFO_TX;
 792		/* Setup RX */
 793		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
 794		*genfifoentry |= GQSPI_GENFIFO_RX;
 795		*genfifoentry |=
 796			zynqmp_qspi_selectspimode(xqspi, transfer->rx_nbits);
 797		xqspi->bytes_to_transfer = 0;
 798		xqspi->bytes_to_receive = transfer->len;
 799		zynq_qspi_setuprxdma(xqspi);
 800	}
 801}
 802
 803/**
 804 * zynqmp_qspi_start_transfer:	Initiates the QSPI transfer
 805 * @master:	Pointer to the spi_master structure which provides
 806 *		information about the controller.
 807 * @qspi:	Pointer to the spi_device structure
 808 * @transfer:	Pointer to the spi_transfer structure which provide information
 809 *		about next transfer parameters
 810 *
 811 * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
 812 * transfer to be completed.
 813 *
 814 * Return:	Number of bytes transferred in the last transfer
 815 */
 816static int zynqmp_qspi_start_transfer(struct spi_master *master,
 817				      struct spi_device *qspi,
 818				      struct spi_transfer *transfer)
 819{
 820	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
 821	u32 genfifoentry = 0x0, transfer_len;
 822
 823	xqspi->txbuf = transfer->tx_buf;
 824	xqspi->rxbuf = transfer->rx_buf;
 825
 826	zynqmp_qspi_setup_transfer(qspi, transfer);
 827
 828	genfifoentry |= xqspi->genfifocs;
 829	genfifoentry |= xqspi->genfifobus;
 830
 831	zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry);
 832
 833	if (xqspi->mode == GQSPI_MODE_DMA)
 834		transfer_len = xqspi->dma_rx_bytes;
 835	else
 836		transfer_len = transfer->len;
 837
 838	xqspi->genfifoentry = genfifoentry;
 839	if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {
 840		genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
 841		genfifoentry |= transfer_len;
 842		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
 843	} else {
 844		int tempcount = transfer_len;
 845		u32 exponent = 8;	/* 2^8 = 256 */
 846		u8 imm_data = tempcount & 0xFF;
 847
 848		tempcount &= ~(tempcount & 0xFF);
 849		/* Immediate entry */
 850		if (tempcount != 0) {
 851			/* Exponent entries */
 852			genfifoentry |= GQSPI_GENFIFO_EXP;
 853			while (tempcount != 0) {
 854				if (tempcount & GQSPI_GENFIFO_EXP_START) {
 855					genfifoentry &=
 856					    ~GQSPI_GENFIFO_IMM_DATA_MASK;
 857					genfifoentry |= exponent;
 858					zynqmp_gqspi_write(xqspi,
 859							   GQSPI_GEN_FIFO_OFST,
 860							   genfifoentry);
 861				}
 862				tempcount = tempcount >> 1;
 863				exponent++;
 864			}
 865		}
 866		if (imm_data != 0) {
 867			genfifoentry &= ~GQSPI_GENFIFO_EXP;
 868			genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
 869			genfifoentry |= (u8) (imm_data & 0xFF);
 870			zynqmp_gqspi_write(xqspi,
 871					   GQSPI_GEN_FIFO_OFST, genfifoentry);
 872		}
 873	}
 874
 875	if ((xqspi->mode == GQSPI_MODE_IO) &&
 876			(xqspi->rxbuf != NULL)) {
 877		/* Dummy generic FIFO entry */
 878		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
 879	}
 880
 881	/* Since we are using manual mode */
 882	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
 883			   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
 884			   GQSPI_CFG_START_GEN_FIFO_MASK);
 885
 886	if (xqspi->txbuf != NULL)
 887		/* Enable interrupts for TX */
 888		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
 889				   GQSPI_IER_TXEMPTY_MASK |
 890					GQSPI_IER_GENFIFOEMPTY_MASK |
 891					GQSPI_IER_TXNOT_FULL_MASK);
 892
 893	if (xqspi->rxbuf != NULL) {
 894		/* Enable interrupts for RX */
 895		if (xqspi->mode == GQSPI_MODE_DMA) {
 896			/* Enable DMA interrupts */
 897			zynqmp_gqspi_write(xqspi,
 898					GQSPI_QSPIDMA_DST_I_EN_OFST,
 899					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
 900		} else {
 901			zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
 902					GQSPI_IER_GENFIFOEMPTY_MASK |
 903					GQSPI_IER_RXNEMPTY_MASK |
 904					GQSPI_IER_RXEMPTY_MASK);
 905		}
 906	}
 907
 908	return transfer->len;
 909}
 910
 911/**
 912 * zynqmp_qspi_suspend:	Suspend method for the QSPI driver
 913 * @_dev:	Address of the platform_device structure
 914 *
 915 * This function stops the QSPI driver queue and disables the QSPI controller
 916 *
 917 * Return:	Always 0
 918 */
 919static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
 920{
 921	struct platform_device *pdev = to_platform_device(dev);
 922	struct spi_master *master = platform_get_drvdata(pdev);
 923
 924	spi_master_suspend(master);
 925
 926	zynqmp_unprepare_transfer_hardware(master);
 927
 928	return 0;
 929}
 930
 931/**
 932 * zynqmp_qspi_resume:	Resume method for the QSPI driver
 933 * @dev:	Address of the platform_device structure
 934 *
 935 * The function starts the QSPI driver queue and initializes the QSPI
 936 * controller
 937 *
 938 * Return:	0 on success; error value otherwise
 939 */
 940static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
 941{
 942	struct platform_device *pdev = to_platform_device(dev);
 943	struct spi_master *master = platform_get_drvdata(pdev);
 944	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
 945	int ret = 0;
 946
 947	ret = clk_enable(xqspi->pclk);
 948	if (ret) {
 949		dev_err(dev, "Cannot enable APB clock.\n");
 950		return ret;
 951	}
 952
 953	ret = clk_enable(xqspi->refclk);
 954	if (ret) {
 955		dev_err(dev, "Cannot enable device clock.\n");
 956		clk_disable(xqspi->pclk);
 957		return ret;
 958	}
 959
 960	spi_master_resume(master);
 961
 962	return 0;
 963}
 964
 965static SIMPLE_DEV_PM_OPS(zynqmp_qspi_dev_pm_ops, zynqmp_qspi_suspend,
 966			 zynqmp_qspi_resume);
 967
 968/**
 969 * zynqmp_qspi_probe:	Probe method for the QSPI driver
 970 * @pdev:	Pointer to the platform_device structure
 971 *
 972 * This function initializes the driver data structures and the hardware.
 973 *
 974 * Return:	0 on success; error value otherwise
 975 */
 976static int zynqmp_qspi_probe(struct platform_device *pdev)
 977{
 978	int ret = 0;
 979	struct spi_master *master;
 980	struct zynqmp_qspi *xqspi;
 981	struct resource *res;
 982	struct device *dev = &pdev->dev;
 983
 984	master = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
 985	if (!master)
 986		return -ENOMEM;
 987
 988	xqspi = spi_master_get_devdata(master);
 989	master->dev.of_node = pdev->dev.of_node;
 990	platform_set_drvdata(pdev, master);
 991
 992	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 993	xqspi->regs = devm_ioremap_resource(&pdev->dev, res);
 994	if (IS_ERR(xqspi->regs)) {
 995		ret = PTR_ERR(xqspi->regs);
 996		goto remove_master;
 997	}
 998
 999	xqspi->dev = dev;
1000	xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
1001	if (IS_ERR(xqspi->pclk)) {
1002		dev_err(dev, "pclk clock not found.\n");
1003		ret = PTR_ERR(xqspi->pclk);
1004		goto remove_master;
1005	}
1006
1007	ret = clk_prepare_enable(xqspi->pclk);
1008	if (ret) {
1009		dev_err(dev, "Unable to enable APB clock.\n");
1010		goto remove_master;
1011	}
1012
1013	xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
1014	if (IS_ERR(xqspi->refclk)) {
1015		dev_err(dev, "ref_clk clock not found.\n");
1016		ret = PTR_ERR(xqspi->refclk);
1017		goto clk_dis_pclk;
1018	}
1019
1020	ret = clk_prepare_enable(xqspi->refclk);
1021	if (ret) {
1022		dev_err(dev, "Unable to enable device clock.\n");
1023		goto clk_dis_pclk;
1024	}
1025
1026	/* QSPI controller initializations */
1027	zynqmp_qspi_init_hw(xqspi);
1028
1029	xqspi->irq = platform_get_irq(pdev, 0);
1030	if (xqspi->irq <= 0) {
1031		ret = -ENXIO;
1032		dev_err(dev, "irq resource not found\n");
1033		goto clk_dis_all;
1034	}
1035	ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
1036			       0, pdev->name, master);
1037	if (ret != 0) {
1038		ret = -ENXIO;
1039		dev_err(dev, "request_irq failed\n");
1040		goto clk_dis_all;
1041	}
1042
1043	master->num_chipselect = GQSPI_DEFAULT_NUM_CS;
1044
1045	master->setup = zynqmp_qspi_setup;
1046	master->set_cs = zynqmp_qspi_chipselect;
1047	master->transfer_one = zynqmp_qspi_start_transfer;
1048	master->prepare_transfer_hardware = zynqmp_prepare_transfer_hardware;
1049	master->unprepare_transfer_hardware =
1050					zynqmp_unprepare_transfer_hardware;
1051	master->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
1052	master->bits_per_word_mask = SPI_BPW_MASK(8);
1053	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
1054			    SPI_TX_DUAL | SPI_TX_QUAD;
1055
1056	if (master->dev.parent == NULL)
1057		master->dev.parent = &master->dev;
1058
1059	ret = spi_register_master(master);
1060	if (ret)
1061		goto clk_dis_all;
1062
1063	return 0;
1064
1065clk_dis_all:
1066	clk_disable_unprepare(xqspi->refclk);
1067clk_dis_pclk:
1068	clk_disable_unprepare(xqspi->pclk);
1069remove_master:
1070	spi_master_put(master);
1071
1072	return ret;
1073}
1074
1075/**
1076 * zynqmp_qspi_remove:	Remove method for the QSPI driver
1077 * @pdev:	Pointer to the platform_device structure
1078 *
1079 * This function is called if a device is physically removed from the system or
1080 * if the driver module is being unloaded. It frees all resources allocated to
1081 * the device.
1082 *
1083 * Return:	0 Always
1084 */
1085static int zynqmp_qspi_remove(struct platform_device *pdev)
1086{
1087	struct spi_master *master = platform_get_drvdata(pdev);
1088	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
1089
1090	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
1091	clk_disable_unprepare(xqspi->refclk);
1092	clk_disable_unprepare(xqspi->pclk);
1093
1094	spi_unregister_master(master);
1095
1096	return 0;
1097}
1098
1099static const struct of_device_id zynqmp_qspi_of_match[] = {
1100	{ .compatible = "xlnx,zynqmp-qspi-1.0", },
1101	{ /* End of table */ }
1102};
1103
1104MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
1105
1106static struct platform_driver zynqmp_qspi_driver = {
1107	.probe = zynqmp_qspi_probe,
1108	.remove = zynqmp_qspi_remove,
1109	.driver = {
1110		.name = "zynqmp-qspi",
1111		.of_match_table = zynqmp_qspi_of_match,
1112		.pm = &zynqmp_qspi_dev_pm_ops,
1113	},
1114};
1115
1116module_platform_driver(zynqmp_qspi_driver);
1117
1118MODULE_AUTHOR("Xilinx, Inc.");
1119MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
1120MODULE_LICENSE("GPL");