brintos

brintos / linux-shallow public Read only

0
0
Text · 22.8 KiB · b67455b Raw
778 lines · c
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 Masks42 *43 * This register contains various control bits that effect the operation44 * of the QSPI controller45 */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 select58 *59 * These are the values used in the calculation of baud rate divisor and60 * 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 Masks68 *69 * All the four interrupt registers (Status/Mask/Enable/Disable) have the same70 * 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 Masks89 *90 * This register is used to enable or disable the QSPI controller91 */92#define ZYNQ_QSPI_ENABLE_ENABLE_MASK	BIT(0) /* QSPI Enable Bit Mask */93 94/*95 * QSPI Linear Configuration Register96 *97 * It is named Linear Configuration but it controls other modes when not in98 * 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	8105 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 different113 * data formats114 */115#define ZYNQ_QSPI_MODEBITS			(SPI_CPOL | SPI_CPHA)116 117/* Maximum number of chip selects */118#define ZYNQ_QSPI_MAX_NUM_CS		2119 120/**121 * struct zynq_qspi - Defines qspi driver instance122 * @dev:		Pointer to the this device's information123 * @regs:		Virtual address of the QSPI controller registers124 * @refclk:		Pointer to the peripheral clock125 * @pclk:		Pointer to the APB clock126 * @irq:		IRQ number127 * @txbuf:		Pointer to the TX buffer128 * @rxbuf:		Pointer to the RX buffer129 * @tx_bytes:		Number of bytes left to transfer130 * @rx_bytes:		Number of bytes left to receive131 * @data_completion:	completion structure132 */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/write148 */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 hardware162 * @xqspi:	Pointer to the zynq_qspi structure163 * @num_cs:	Number of connected CS (to enable dual memories if needed)164 *165 * The default settings of the QSPI controller's configurable parameters on166 * reset are167 *	- Host mode168 *	- Baud rate divisor is set to 2169 *	- Tx threshold set to 1l Rx threshold set to 32170 *	- Flash memory interface mode enabled171 *	- Size of the word to be transferred as 8 bit172 * This function performs the following actions173 *	- Disable and clear all the interrupts174 *	- Enable manual target select175 *	- Enable manual start176 *	- Deselect all the chip select lines177 *	- Set the size of the word to be transferred as 32 bit178 *	- Set the little endian mode of TX FIFO and179 *	- Enable the QSPI controller180 */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 buffer242 * @xqspi:	Pointer to the zynq_qspi structure243 * @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 TxFIFO263 * @xqspi:	Pointer to the zynq_qspi structure264 * @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 line287 * @spi:	Pointer to the spi_device structure288 * @assert:	1 for select or 0 for deselect the chip select line289 */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		else302			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	else312		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 transfer319 * @xqspi:	Pointer to the zynq_qspi structure320 * @spi:	Pointer to the spi_device structure321 *322 * Sets the operational mode of QSPI controller for the next QSPI transfer and323 * sets the requested clock frequency.324 *325 * Return:	0 on success and -EINVAL on invalid input parameter326 *327 * Note: If the requested frequency is not an exact match with what can be328 * obtained using the prescalar value, the driver sets the clock frequency which329 * is lower than the requested frequency (maximum lower) for the transfer. If330 * the requested frequency is higher or lower than that is supported by the QSPI331 * controller the driver will set the highest or lowest frequency supported by332 * 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 frequency340	 * The baud rate divisor is not a direct mapping to the value written341	 * into the configuration register (config_reg[5:3])342	 * i.e. 000 - divide by 2343	 *      001 - divide by 4344	 *      ----------------345	 *      111 - divide by 256346	 */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 controller371 * @spi:	Pointer to the spi_device structure372 *373 * Sets the operational mode of QSPI controller for the next QSPI transfer, baud374 * rate and divisor value to setup the requested qspi clock.375 *376 * Return:	0 on success and error value on failure377 */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 possible396 * @xqspi:	Pointer to the zynq_qspi structure397 * @txcount:	Maximum number of words to write398 * @txempty:	Indicates that TxFIFO is empty399 */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 possible436 * @xqspi:	Pointer to the zynq_qspi structure437 * @rxcount:	Maximum number of words to read438 */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 controller464 * @irq:	IRQ number465 * @dev_id:	Pointer to the xqspi structure466 *467 * This function handles TX empty only.468 * On TX empty interrupt this function reads the received data from RX FIFO and469 * 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 send499			 * 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 transfer516 * @mem: the SPI memory517 * @op: the memory operation to execute518 *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 = kmalloc(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 driver625 * @pdev:	Pointer to the platform_device structure626 *627 * This function initializes the driver data structures and the hardware.628 *629 * Return:	0 on success and error value on failure630 */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 driver736 * @pdev:	Pointer to the platform_device structure737 *738 * This function is called if a device is physically removed from the system or739 * if the driver module is being unloaded. It frees all resources allocated to740 * the device.741 *742 * Return:	0 on success and error value on failure743 */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 driver763 */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