xref: /linux/drivers/spi/spi-zynqmp-gqspi.c (revision 165f2d2858013253042809df082b8df7e34e86d7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Xilinx Zynq UltraScale+ MPSoC Quad-SPI (QSPI) controller driver
4  * (master mode only)
5  *
6  * Copyright (C) 2009 - 2015 Xilinx, Inc.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/dmaengine.h>
13 #include <linux/firmware/xlnx-zynqmp.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/module.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_address.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/spi/spi.h>
22 #include <linux/spinlock.h>
23 #include <linux/workqueue.h>
24 
25 /* Generic QSPI register offsets */
26 #define GQSPI_CONFIG_OFST		0x00000100
27 #define GQSPI_ISR_OFST			0x00000104
28 #define GQSPI_IDR_OFST			0x0000010C
29 #define GQSPI_IER_OFST			0x00000108
30 #define GQSPI_IMASK_OFST		0x00000110
31 #define GQSPI_EN_OFST			0x00000114
32 #define GQSPI_TXD_OFST			0x0000011C
33 #define GQSPI_RXD_OFST			0x00000120
34 #define GQSPI_TX_THRESHOLD_OFST		0x00000128
35 #define GQSPI_RX_THRESHOLD_OFST		0x0000012C
36 #define GQSPI_LPBK_DLY_ADJ_OFST		0x00000138
37 #define GQSPI_GEN_FIFO_OFST		0x00000140
38 #define GQSPI_SEL_OFST			0x00000144
39 #define GQSPI_GF_THRESHOLD_OFST		0x00000150
40 #define GQSPI_FIFO_CTRL_OFST		0x0000014C
41 #define GQSPI_QSPIDMA_DST_CTRL_OFST	0x0000080C
42 #define GQSPI_QSPIDMA_DST_SIZE_OFST	0x00000804
43 #define GQSPI_QSPIDMA_DST_STS_OFST	0x00000808
44 #define GQSPI_QSPIDMA_DST_I_STS_OFST	0x00000814
45 #define GQSPI_QSPIDMA_DST_I_EN_OFST	0x00000818
46 #define GQSPI_QSPIDMA_DST_I_DIS_OFST	0x0000081C
47 #define GQSPI_QSPIDMA_DST_I_MASK_OFST	0x00000820
48 #define GQSPI_QSPIDMA_DST_ADDR_OFST	0x00000800
49 #define GQSPI_QSPIDMA_DST_ADDR_MSB_OFST 0x00000828
50 
51 /* GQSPI register bit masks */
52 #define GQSPI_SEL_MASK				0x00000001
53 #define GQSPI_EN_MASK				0x00000001
54 #define GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK	0x00000020
55 #define GQSPI_ISR_WR_TO_CLR_MASK		0x00000002
56 #define GQSPI_IDR_ALL_MASK			0x00000FBE
57 #define GQSPI_CFG_MODE_EN_MASK			0xC0000000
58 #define GQSPI_CFG_GEN_FIFO_START_MODE_MASK	0x20000000
59 #define GQSPI_CFG_ENDIAN_MASK			0x04000000
60 #define GQSPI_CFG_EN_POLL_TO_MASK		0x00100000
61 #define GQSPI_CFG_WP_HOLD_MASK			0x00080000
62 #define GQSPI_CFG_BAUD_RATE_DIV_MASK		0x00000038
63 #define GQSPI_CFG_CLK_PHA_MASK			0x00000004
64 #define GQSPI_CFG_CLK_POL_MASK			0x00000002
65 #define GQSPI_CFG_START_GEN_FIFO_MASK		0x10000000
66 #define GQSPI_GENFIFO_IMM_DATA_MASK		0x000000FF
67 #define GQSPI_GENFIFO_DATA_XFER			0x00000100
68 #define GQSPI_GENFIFO_EXP			0x00000200
69 #define GQSPI_GENFIFO_MODE_SPI			0x00000400
70 #define GQSPI_GENFIFO_MODE_DUALSPI		0x00000800
71 #define GQSPI_GENFIFO_MODE_QUADSPI		0x00000C00
72 #define GQSPI_GENFIFO_MODE_MASK			0x00000C00
73 #define GQSPI_GENFIFO_CS_LOWER			0x00001000
74 #define GQSPI_GENFIFO_CS_UPPER			0x00002000
75 #define GQSPI_GENFIFO_BUS_LOWER			0x00004000
76 #define GQSPI_GENFIFO_BUS_UPPER			0x00008000
77 #define GQSPI_GENFIFO_BUS_BOTH			0x0000C000
78 #define GQSPI_GENFIFO_BUS_MASK			0x0000C000
79 #define GQSPI_GENFIFO_TX			0x00010000
80 #define GQSPI_GENFIFO_RX			0x00020000
81 #define GQSPI_GENFIFO_STRIPE			0x00040000
82 #define GQSPI_GENFIFO_POLL			0x00080000
83 #define GQSPI_GENFIFO_EXP_START			0x00000100
84 #define GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK	0x00000004
85 #define GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK	0x00000002
86 #define GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK	0x00000001
87 #define GQSPI_ISR_RXEMPTY_MASK			0x00000800
88 #define GQSPI_ISR_GENFIFOFULL_MASK		0x00000400
89 #define GQSPI_ISR_GENFIFONOT_FULL_MASK		0x00000200
90 #define GQSPI_ISR_TXEMPTY_MASK			0x00000100
91 #define GQSPI_ISR_GENFIFOEMPTY_MASK		0x00000080
92 #define GQSPI_ISR_RXFULL_MASK			0x00000020
93 #define GQSPI_ISR_RXNEMPTY_MASK			0x00000010
94 #define GQSPI_ISR_TXFULL_MASK			0x00000008
95 #define GQSPI_ISR_TXNOT_FULL_MASK		0x00000004
96 #define GQSPI_ISR_POLL_TIME_EXPIRE_MASK		0x00000002
97 #define GQSPI_IER_TXNOT_FULL_MASK		0x00000004
98 #define GQSPI_IER_RXEMPTY_MASK			0x00000800
99 #define GQSPI_IER_POLL_TIME_EXPIRE_MASK		0x00000002
100 #define GQSPI_IER_RXNEMPTY_MASK			0x00000010
101 #define GQSPI_IER_GENFIFOEMPTY_MASK		0x00000080
102 #define GQSPI_IER_TXEMPTY_MASK			0x00000100
103 #define GQSPI_QSPIDMA_DST_INTR_ALL_MASK		0x000000FE
104 #define GQSPI_QSPIDMA_DST_STS_WTC		0x0000E000
105 #define GQSPI_CFG_MODE_EN_DMA_MASK		0x80000000
106 #define GQSPI_ISR_IDR_MASK			0x00000994
107 #define GQSPI_QSPIDMA_DST_I_EN_DONE_MASK	0x00000002
108 #define GQSPI_QSPIDMA_DST_I_STS_DONE_MASK	0x00000002
109 #define GQSPI_IRQ_MASK				0x00000980
110 
111 #define GQSPI_CFG_BAUD_RATE_DIV_SHIFT		3
112 #define GQSPI_GENFIFO_CS_SETUP			0x4
113 #define GQSPI_GENFIFO_CS_HOLD			0x3
114 #define GQSPI_TXD_DEPTH				64
115 #define GQSPI_RX_FIFO_THRESHOLD			32
116 #define GQSPI_RX_FIFO_FILL	(GQSPI_RX_FIFO_THRESHOLD * 4)
117 #define GQSPI_TX_FIFO_THRESHOLD_RESET_VAL	32
118 #define GQSPI_TX_FIFO_FILL	(GQSPI_TXD_DEPTH -\
119 				GQSPI_TX_FIFO_THRESHOLD_RESET_VAL)
120 #define GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL	0X10
121 #define GQSPI_QSPIDMA_DST_CTRL_RESET_VAL	0x803FFA00
122 #define GQSPI_SELECT_FLASH_CS_LOWER		0x1
123 #define GQSPI_SELECT_FLASH_CS_UPPER		0x2
124 #define GQSPI_SELECT_FLASH_CS_BOTH		0x3
125 #define GQSPI_SELECT_FLASH_BUS_LOWER		0x1
126 #define GQSPI_SELECT_FLASH_BUS_UPPER		0x2
127 #define GQSPI_SELECT_FLASH_BUS_BOTH		0x3
128 #define GQSPI_BAUD_DIV_MAX	7	/* Baud rate divisor maximum */
129 #define GQSPI_BAUD_DIV_SHIFT	2	/* Baud rate divisor shift */
130 #define GQSPI_SELECT_MODE_SPI		0x1
131 #define GQSPI_SELECT_MODE_DUALSPI	0x2
132 #define GQSPI_SELECT_MODE_QUADSPI	0x4
133 #define GQSPI_DMA_UNALIGN		0x3
134 #define GQSPI_DEFAULT_NUM_CS	1	/* Default number of chip selects */
135 
136 #define SPI_AUTOSUSPEND_TIMEOUT		3000
137 enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
138 static const struct zynqmp_eemi_ops *eemi_ops;
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  */
158 struct 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  */
181 static 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  */
192 static 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  */
204 static 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  */
263 static 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  */
339 static 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  */
356 static int zynqmp_prepare_transfer_hardware(struct spi_master *master)
357 {
358 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
359 
360 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
361 	return 0;
362 }
363 
364 /**
365  * zynqmp_unprepare_transfer_hardware:	Relaxes hardware after transfer
366  * @master:	Pointer to the spi_master structure which provides
367  *		information about the controller.
368  *
369  * This function disables the SPI master controller.
370  *
371  * Return:	Always 0
372  */
373 static int zynqmp_unprepare_transfer_hardware(struct spi_master *master)
374 {
375 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
376 
377 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
378 	return 0;
379 }
380 
381 /**
382  * zynqmp_qspi_chipselect:	Select or deselect the chip select line
383  * @qspi:	Pointer to the spi_device structure
384  * @is_high:	Select(0) or deselect (1) the chip select line
385  */
386 static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high)
387 {
388 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
389 	ulong timeout;
390 	u32 genfifoentry = 0x0, statusreg;
391 
392 	genfifoentry |= GQSPI_GENFIFO_MODE_SPI;
393 	genfifoentry |= xqspi->genfifobus;
394 
395 	if (!is_high) {
396 		genfifoentry |= xqspi->genfifocs;
397 		genfifoentry |= GQSPI_GENFIFO_CS_SETUP;
398 	} else {
399 		genfifoentry |= GQSPI_GENFIFO_CS_HOLD;
400 	}
401 
402 	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
403 
404 	/* Manually start the generic FIFO command */
405 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
406 			zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
407 			GQSPI_CFG_START_GEN_FIFO_MASK);
408 
409 	timeout = jiffies + msecs_to_jiffies(1000);
410 
411 	/* Wait until the generic FIFO command is empty */
412 	do {
413 		statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
414 
415 		if ((statusreg & GQSPI_ISR_GENFIFOEMPTY_MASK) &&
416 			(statusreg & GQSPI_ISR_TXEMPTY_MASK))
417 			break;
418 		else
419 			cpu_relax();
420 	} while (!time_after_eq(jiffies, timeout));
421 
422 	if (time_after_eq(jiffies, timeout))
423 		dev_err(xqspi->dev, "Chip select timed out\n");
424 }
425 
426 /**
427  * zynqmp_qspi_setup_transfer:	Configure QSPI controller for specified
428  *				transfer
429  * @qspi:	Pointer to the spi_device structure
430  * @transfer:	Pointer to the spi_transfer structure which provides
431  *		information about next transfer setup parameters
432  *
433  * Sets the operational mode of QSPI controller for the next QSPI transfer and
434  * sets the requested clock frequency.
435  *
436  * Return:	Always 0
437  *
438  * Note:
439  *	If the requested frequency is not an exact match with what can be
440  *	obtained using the pre-scalar value, the driver sets the clock
441  *	frequency which is lower than the requested frequency (maximum lower)
442  *	for the transfer.
443  *
444  *	If the requested frequency is higher or lower than that is supported
445  *	by the QSPI controller the driver will set the highest or lowest
446  *	frequency supported by controller.
447  */
448 static int zynqmp_qspi_setup_transfer(struct spi_device *qspi,
449 				      struct spi_transfer *transfer)
450 {
451 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
452 	ulong clk_rate;
453 	u32 config_reg, req_hz, baud_rate_val = 0;
454 
455 	if (transfer)
456 		req_hz = transfer->speed_hz;
457 	else
458 		req_hz = qspi->max_speed_hz;
459 
460 	/* Set the clock frequency */
461 	/* If req_hz == 0, default to lowest speed */
462 	clk_rate = clk_get_rate(xqspi->refclk);
463 
464 	while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
465 	       (clk_rate /
466 		(GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz)
467 		baud_rate_val++;
468 
469 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
470 
471 	/* Set the QSPI clock phase and clock polarity */
472 	config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
473 
474 	if (qspi->mode & SPI_CPHA)
475 		config_reg |= GQSPI_CFG_CLK_PHA_MASK;
476 	if (qspi->mode & SPI_CPOL)
477 		config_reg |= GQSPI_CFG_CLK_POL_MASK;
478 
479 	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
480 	config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
481 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
482 	return 0;
483 }
484 
485 /**
486  * zynqmp_qspi_setup:	Configure the QSPI controller
487  * @qspi:	Pointer to the spi_device structure
488  *
489  * Sets the operational mode of QSPI controller for the next QSPI transfer,
490  * baud rate and divisor value to setup the requested qspi clock.
491  *
492  * Return:	0 on success; error value otherwise.
493  */
494 static int zynqmp_qspi_setup(struct spi_device *qspi)
495 {
496 	if (qspi->master->busy)
497 		return -EBUSY;
498 	return 0;
499 }
500 
501 /**
502  * zynqmp_qspi_filltxfifo:	Fills the TX FIFO as long as there is room in
503  *				the FIFO or the bytes required to be
504  *				transmitted.
505  * @xqspi:	Pointer to the zynqmp_qspi structure
506  * @size:	Number of bytes to be copied from TX buffer to TX FIFO
507  */
508 static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
509 {
510 	u32 count = 0, intermediate;
511 
512 	while ((xqspi->bytes_to_transfer > 0) && (count < size)) {
513 		memcpy(&intermediate, xqspi->txbuf, 4);
514 		zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
515 
516 		if (xqspi->bytes_to_transfer >= 4) {
517 			xqspi->txbuf += 4;
518 			xqspi->bytes_to_transfer -= 4;
519 		} else {
520 			xqspi->txbuf += xqspi->bytes_to_transfer;
521 			xqspi->bytes_to_transfer = 0;
522 		}
523 		count++;
524 	}
525 }
526 
527 /**
528  * zynqmp_qspi_readrxfifo:	Fills the RX FIFO as long as there is room in
529  *				the FIFO.
530  * @xqspi:	Pointer to the zynqmp_qspi structure
531  * @size:	Number of bytes to be copied from RX buffer to RX FIFO
532  */
533 static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
534 {
535 	ulong data;
536 	int count = 0;
537 
538 	while ((count < size) && (xqspi->bytes_to_receive > 0)) {
539 		if (xqspi->bytes_to_receive >= 4) {
540 			(*(u32 *) xqspi->rxbuf) =
541 			zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
542 			xqspi->rxbuf += 4;
543 			xqspi->bytes_to_receive -= 4;
544 			count += 4;
545 		} else {
546 			data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
547 			count += xqspi->bytes_to_receive;
548 			zynqmp_qspi_copy_read_data(xqspi, data,
549 						   xqspi->bytes_to_receive);
550 			xqspi->bytes_to_receive = 0;
551 		}
552 	}
553 }
554 
555 /**
556  * zynqmp_process_dma_irq:	Handler for DMA done interrupt of QSPI
557  *				controller
558  * @xqspi:	zynqmp_qspi instance pointer
559  *
560  * This function handles DMA interrupt only.
561  */
562 static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
563 {
564 	u32 config_reg, genfifoentry;
565 
566 	dma_unmap_single(xqspi->dev, xqspi->dma_addr,
567 				xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
568 	xqspi->rxbuf += xqspi->dma_rx_bytes;
569 	xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
570 	xqspi->dma_rx_bytes = 0;
571 
572 	/* Disabling the DMA interrupts */
573 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST,
574 					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
575 
576 	if (xqspi->bytes_to_receive > 0) {
577 		/* Switch to IO mode,for remaining bytes to receive */
578 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
579 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
580 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
581 
582 		/* Initiate the transfer of remaining bytes */
583 		genfifoentry = xqspi->genfifoentry;
584 		genfifoentry |= xqspi->bytes_to_receive;
585 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
586 
587 		/* Dummy generic FIFO entry */
588 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
589 
590 		/* Manual start */
591 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
592 			(zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
593 			GQSPI_CFG_START_GEN_FIFO_MASK));
594 
595 		/* Enable the RX interrupts for IO mode */
596 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
597 				GQSPI_IER_GENFIFOEMPTY_MASK |
598 				GQSPI_IER_RXNEMPTY_MASK |
599 				GQSPI_IER_RXEMPTY_MASK);
600 	}
601 }
602 
603 /**
604  * zynqmp_qspi_irq:	Interrupt service routine of the QSPI controller
605  * @irq:	IRQ number
606  * @dev_id:	Pointer to the xqspi structure
607  *
608  * This function handles TX empty only.
609  * On TX empty interrupt this function reads the received data from RX FIFO
610  * and fills the TX FIFO if there is any data remaining to be transferred.
611  *
612  * Return:	IRQ_HANDLED when interrupt is handled
613  *		IRQ_NONE otherwise.
614  */
615 static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
616 {
617 	struct spi_master *master = dev_id;
618 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
619 	int ret = IRQ_NONE;
620 	u32 status, mask, dma_status = 0;
621 
622 	status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
623 	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status);
624 	mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST)));
625 
626 	/* Read and clear DMA status */
627 	if (xqspi->mode == GQSPI_MODE_DMA) {
628 		dma_status =
629 			zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST);
630 		zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
631 								dma_status);
632 	}
633 
634 	if (mask & GQSPI_ISR_TXNOT_FULL_MASK) {
635 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
636 		ret = IRQ_HANDLED;
637 	}
638 
639 	if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) {
640 		zynqmp_process_dma_irq(xqspi);
641 		ret = IRQ_HANDLED;
642 	} else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
643 			(mask & GQSPI_IER_GENFIFOEMPTY_MASK)) {
644 		zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
645 		ret = IRQ_HANDLED;
646 	}
647 
648 	if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0)
649 			&& ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
650 		zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK);
651 		spi_finalize_current_transfer(master);
652 		ret = IRQ_HANDLED;
653 	}
654 	return ret;
655 }
656 
657 /**
658  * zynqmp_qspi_selectspimode:	Selects SPI mode - x1 or x2 or x4.
659  * @xqspi:	xqspi is a pointer to the GQSPI instance
660  * @spimode:	spimode - SPI or DUAL or QUAD.
661  * Return:	Mask to set desired SPI mode in GENFIFO entry.
662  */
663 static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi,
664 						u8 spimode)
665 {
666 	u32 mask = 0;
667 
668 	switch (spimode) {
669 	case GQSPI_SELECT_MODE_DUALSPI:
670 		mask = GQSPI_GENFIFO_MODE_DUALSPI;
671 		break;
672 	case GQSPI_SELECT_MODE_QUADSPI:
673 		mask = GQSPI_GENFIFO_MODE_QUADSPI;
674 		break;
675 	case GQSPI_SELECT_MODE_SPI:
676 		mask = GQSPI_GENFIFO_MODE_SPI;
677 		break;
678 	default:
679 		dev_warn(xqspi->dev, "Invalid SPI mode\n");
680 	}
681 
682 	return mask;
683 }
684 
685 /**
686  * zynq_qspi_setuprxdma:	This function sets up the RX DMA operation
687  * @xqspi:	xqspi is a pointer to the GQSPI instance.
688  */
689 static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
690 {
691 	u32 rx_bytes, rx_rem, config_reg;
692 	dma_addr_t addr;
693 	u64 dma_align =  (u64)(uintptr_t)xqspi->rxbuf;
694 
695 	if ((xqspi->bytes_to_receive < 8) ||
696 		((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
697 		/* Setting to IO mode */
698 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
699 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
700 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
701 		xqspi->mode = GQSPI_MODE_IO;
702 		xqspi->dma_rx_bytes = 0;
703 		return;
704 	}
705 
706 	rx_rem = xqspi->bytes_to_receive % 4;
707 	rx_bytes = (xqspi->bytes_to_receive - rx_rem);
708 
709 	addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
710 						rx_bytes, DMA_FROM_DEVICE);
711 	if (dma_mapping_error(xqspi->dev, addr))
712 		dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
713 
714 	xqspi->dma_rx_bytes = rx_bytes;
715 	xqspi->dma_addr = addr;
716 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
717 				(u32)(addr & 0xffffffff));
718 	addr = ((addr >> 16) >> 16);
719 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
720 				((u32)addr) & 0xfff);
721 
722 	/* Enabling the DMA mode */
723 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
724 	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
725 	config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
726 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
727 
728 	/* Switch to DMA mode */
729 	xqspi->mode = GQSPI_MODE_DMA;
730 
731 	/* Write the number of bytes to transfer */
732 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
733 }
734 
735 /**
736  * zynqmp_qspi_txrxsetup:	This function checks the TX/RX buffers in
737  *				the transfer and sets up the GENFIFO entries,
738  *				TX FIFO as required.
739  * @xqspi:	xqspi is a pointer to the GQSPI instance.
740  * @transfer:	It is a pointer to the structure containing transfer data.
741  * @genfifoentry:	genfifoentry is pointer to the variable in which
742  *			GENFIFO	mask is returned to calling function
743  */
744 static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi,
745 				  struct spi_transfer *transfer,
746 				  u32 *genfifoentry)
747 {
748 	u32 config_reg;
749 
750 	/* Transmit */
751 	if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) {
752 		/* Setup data to be TXed */
753 		*genfifoentry &= ~GQSPI_GENFIFO_RX;
754 		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
755 		*genfifoentry |= GQSPI_GENFIFO_TX;
756 		*genfifoentry |=
757 			zynqmp_qspi_selectspimode(xqspi, transfer->tx_nbits);
758 		xqspi->bytes_to_transfer = transfer->len;
759 		if (xqspi->mode == GQSPI_MODE_DMA) {
760 			config_reg = zynqmp_gqspi_read(xqspi,
761 							GQSPI_CONFIG_OFST);
762 			config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
763 			zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
764 								config_reg);
765 			xqspi->mode = GQSPI_MODE_IO;
766 		}
767 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
768 		/* Discard RX data */
769 		xqspi->bytes_to_receive = 0;
770 	} else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) {
771 		/* Receive */
772 
773 		/* TX auto fill */
774 		*genfifoentry &= ~GQSPI_GENFIFO_TX;
775 		/* Setup RX */
776 		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
777 		*genfifoentry |= GQSPI_GENFIFO_RX;
778 		*genfifoentry |=
779 			zynqmp_qspi_selectspimode(xqspi, transfer->rx_nbits);
780 		xqspi->bytes_to_transfer = 0;
781 		xqspi->bytes_to_receive = transfer->len;
782 		zynq_qspi_setuprxdma(xqspi);
783 	}
784 }
785 
786 /**
787  * zynqmp_qspi_start_transfer:	Initiates the QSPI transfer
788  * @master:	Pointer to the spi_master structure which provides
789  *		information about the controller.
790  * @qspi:	Pointer to the spi_device structure
791  * @transfer:	Pointer to the spi_transfer structure which provide information
792  *		about next transfer parameters
793  *
794  * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
795  * transfer to be completed.
796  *
797  * Return:	Number of bytes transferred in the last transfer
798  */
799 static int zynqmp_qspi_start_transfer(struct spi_master *master,
800 				      struct spi_device *qspi,
801 				      struct spi_transfer *transfer)
802 {
803 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
804 	u32 genfifoentry = 0x0, transfer_len;
805 
806 	xqspi->txbuf = transfer->tx_buf;
807 	xqspi->rxbuf = transfer->rx_buf;
808 
809 	zynqmp_qspi_setup_transfer(qspi, transfer);
810 
811 	genfifoentry |= xqspi->genfifocs;
812 	genfifoentry |= xqspi->genfifobus;
813 
814 	zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry);
815 
816 	if (xqspi->mode == GQSPI_MODE_DMA)
817 		transfer_len = xqspi->dma_rx_bytes;
818 	else
819 		transfer_len = transfer->len;
820 
821 	xqspi->genfifoentry = genfifoentry;
822 	if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {
823 		genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
824 		genfifoentry |= transfer_len;
825 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
826 	} else {
827 		int tempcount = transfer_len;
828 		u32 exponent = 8;	/* 2^8 = 256 */
829 		u8 imm_data = tempcount & 0xFF;
830 
831 		tempcount &= ~(tempcount & 0xFF);
832 		/* Immediate entry */
833 		if (tempcount != 0) {
834 			/* Exponent entries */
835 			genfifoentry |= GQSPI_GENFIFO_EXP;
836 			while (tempcount != 0) {
837 				if (tempcount & GQSPI_GENFIFO_EXP_START) {
838 					genfifoentry &=
839 					    ~GQSPI_GENFIFO_IMM_DATA_MASK;
840 					genfifoentry |= exponent;
841 					zynqmp_gqspi_write(xqspi,
842 							   GQSPI_GEN_FIFO_OFST,
843 							   genfifoentry);
844 				}
845 				tempcount = tempcount >> 1;
846 				exponent++;
847 			}
848 		}
849 		if (imm_data != 0) {
850 			genfifoentry &= ~GQSPI_GENFIFO_EXP;
851 			genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
852 			genfifoentry |= (u8) (imm_data & 0xFF);
853 			zynqmp_gqspi_write(xqspi,
854 					   GQSPI_GEN_FIFO_OFST, genfifoentry);
855 		}
856 	}
857 
858 	if ((xqspi->mode == GQSPI_MODE_IO) &&
859 			(xqspi->rxbuf != NULL)) {
860 		/* Dummy generic FIFO entry */
861 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
862 	}
863 
864 	/* Since we are using manual mode */
865 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
866 			   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
867 			   GQSPI_CFG_START_GEN_FIFO_MASK);
868 
869 	if (xqspi->txbuf != NULL)
870 		/* Enable interrupts for TX */
871 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
872 				   GQSPI_IER_TXEMPTY_MASK |
873 					GQSPI_IER_GENFIFOEMPTY_MASK |
874 					GQSPI_IER_TXNOT_FULL_MASK);
875 
876 	if (xqspi->rxbuf != NULL) {
877 		/* Enable interrupts for RX */
878 		if (xqspi->mode == GQSPI_MODE_DMA) {
879 			/* Enable DMA interrupts */
880 			zynqmp_gqspi_write(xqspi,
881 					GQSPI_QSPIDMA_DST_I_EN_OFST,
882 					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
883 		} else {
884 			zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
885 					GQSPI_IER_GENFIFOEMPTY_MASK |
886 					GQSPI_IER_RXNEMPTY_MASK |
887 					GQSPI_IER_RXEMPTY_MASK);
888 		}
889 	}
890 
891 	return transfer->len;
892 }
893 
894 /**
895  * zynqmp_qspi_suspend:	Suspend method for the QSPI driver
896  * @_dev:	Address of the platform_device structure
897  *
898  * This function stops the QSPI driver queue and disables the QSPI controller
899  *
900  * Return:	Always 0
901  */
902 static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
903 {
904 	struct spi_master *master = dev_get_drvdata(dev);
905 
906 	spi_master_suspend(master);
907 
908 	zynqmp_unprepare_transfer_hardware(master);
909 
910 	return 0;
911 }
912 
913 /**
914  * zynqmp_qspi_resume:	Resume method for the QSPI driver
915  * @dev:	Address of the platform_device structure
916  *
917  * The function starts the QSPI driver queue and initializes the QSPI
918  * controller
919  *
920  * Return:	0 on success; error value otherwise
921  */
922 static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
923 {
924 	struct spi_master *master = dev_get_drvdata(dev);
925 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
926 	int ret = 0;
927 
928 	ret = clk_enable(xqspi->pclk);
929 	if (ret) {
930 		dev_err(dev, "Cannot enable APB clock.\n");
931 		return ret;
932 	}
933 
934 	ret = clk_enable(xqspi->refclk);
935 	if (ret) {
936 		dev_err(dev, "Cannot enable device clock.\n");
937 		clk_disable(xqspi->pclk);
938 		return ret;
939 	}
940 
941 	spi_master_resume(master);
942 
943 	clk_disable(xqspi->refclk);
944 	clk_disable(xqspi->pclk);
945 	return 0;
946 }
947 
948 /**
949  * zynqmp_runtime_suspend - Runtime suspend method for the SPI driver
950  * @dev:	Address of the platform_device structure
951  *
952  * This function disables the clocks
953  *
954  * Return:	Always 0
955  */
956 static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
957 {
958 	struct spi_master *master = dev_get_drvdata(dev);
959 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
960 
961 	clk_disable(xqspi->refclk);
962 	clk_disable(xqspi->pclk);
963 
964 	return 0;
965 }
966 
967 /**
968  * zynqmp_runtime_resume - Runtime resume method for the SPI driver
969  * @dev:	Address of the platform_device structure
970  *
971  * This function enables the clocks
972  *
973  * Return:	0 on success and error value on error
974  */
975 static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
976 {
977 	struct spi_master *master = dev_get_drvdata(dev);
978 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
979 	int ret;
980 
981 	ret = clk_enable(xqspi->pclk);
982 	if (ret) {
983 		dev_err(dev, "Cannot enable APB clock.\n");
984 		return ret;
985 	}
986 
987 	ret = clk_enable(xqspi->refclk);
988 	if (ret) {
989 		dev_err(dev, "Cannot enable device clock.\n");
990 		clk_disable(xqspi->pclk);
991 		return ret;
992 	}
993 
994 	return 0;
995 }
996 
997 static const struct dev_pm_ops zynqmp_qspi_dev_pm_ops = {
998 	SET_RUNTIME_PM_OPS(zynqmp_runtime_suspend,
999 			   zynqmp_runtime_resume, NULL)
1000 	SET_SYSTEM_SLEEP_PM_OPS(zynqmp_qspi_suspend, zynqmp_qspi_resume)
1001 };
1002 
1003 /**
1004  * zynqmp_qspi_probe:	Probe method for the QSPI driver
1005  * @pdev:	Pointer to the platform_device structure
1006  *
1007  * This function initializes the driver data structures and the hardware.
1008  *
1009  * Return:	0 on success; error value otherwise
1010  */
1011 static int zynqmp_qspi_probe(struct platform_device *pdev)
1012 {
1013 	int ret = 0;
1014 	struct spi_master *master;
1015 	struct zynqmp_qspi *xqspi;
1016 	struct device *dev = &pdev->dev;
1017 
1018 	eemi_ops = zynqmp_pm_get_eemi_ops();
1019 	if (IS_ERR(eemi_ops))
1020 		return PTR_ERR(eemi_ops);
1021 
1022 	master = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
1023 	if (!master)
1024 		return -ENOMEM;
1025 
1026 	xqspi = spi_master_get_devdata(master);
1027 	master->dev.of_node = pdev->dev.of_node;
1028 	platform_set_drvdata(pdev, master);
1029 
1030 	xqspi->regs = devm_platform_ioremap_resource(pdev, 0);
1031 	if (IS_ERR(xqspi->regs)) {
1032 		ret = PTR_ERR(xqspi->regs);
1033 		goto remove_master;
1034 	}
1035 
1036 	xqspi->dev = dev;
1037 	xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
1038 	if (IS_ERR(xqspi->pclk)) {
1039 		dev_err(dev, "pclk clock not found.\n");
1040 		ret = PTR_ERR(xqspi->pclk);
1041 		goto remove_master;
1042 	}
1043 
1044 	ret = clk_prepare_enable(xqspi->pclk);
1045 	if (ret) {
1046 		dev_err(dev, "Unable to enable APB clock.\n");
1047 		goto remove_master;
1048 	}
1049 
1050 	xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
1051 	if (IS_ERR(xqspi->refclk)) {
1052 		dev_err(dev, "ref_clk clock not found.\n");
1053 		ret = PTR_ERR(xqspi->refclk);
1054 		goto clk_dis_pclk;
1055 	}
1056 
1057 	ret = clk_prepare_enable(xqspi->refclk);
1058 	if (ret) {
1059 		dev_err(dev, "Unable to enable device clock.\n");
1060 		goto clk_dis_pclk;
1061 	}
1062 
1063 	pm_runtime_use_autosuspend(&pdev->dev);
1064 	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1065 	pm_runtime_set_active(&pdev->dev);
1066 	pm_runtime_enable(&pdev->dev);
1067 	/* QSPI controller initializations */
1068 	zynqmp_qspi_init_hw(xqspi);
1069 
1070 	pm_runtime_mark_last_busy(&pdev->dev);
1071 	pm_runtime_put_autosuspend(&pdev->dev);
1072 	xqspi->irq = platform_get_irq(pdev, 0);
1073 	if (xqspi->irq <= 0) {
1074 		ret = -ENXIO;
1075 		goto clk_dis_all;
1076 	}
1077 	ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
1078 			       0, pdev->name, master);
1079 	if (ret != 0) {
1080 		ret = -ENXIO;
1081 		dev_err(dev, "request_irq failed\n");
1082 		goto clk_dis_all;
1083 	}
1084 
1085 	master->num_chipselect = GQSPI_DEFAULT_NUM_CS;
1086 
1087 	master->setup = zynqmp_qspi_setup;
1088 	master->set_cs = zynqmp_qspi_chipselect;
1089 	master->transfer_one = zynqmp_qspi_start_transfer;
1090 	master->prepare_transfer_hardware = zynqmp_prepare_transfer_hardware;
1091 	master->unprepare_transfer_hardware =
1092 					zynqmp_unprepare_transfer_hardware;
1093 	master->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
1094 	master->bits_per_word_mask = SPI_BPW_MASK(8);
1095 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
1096 			    SPI_TX_DUAL | SPI_TX_QUAD;
1097 
1098 	if (master->dev.parent == NULL)
1099 		master->dev.parent = &master->dev;
1100 
1101 	ret = spi_register_master(master);
1102 	if (ret)
1103 		goto clk_dis_all;
1104 
1105 	return 0;
1106 
1107 clk_dis_all:
1108 	pm_runtime_set_suspended(&pdev->dev);
1109 	pm_runtime_disable(&pdev->dev);
1110 	clk_disable_unprepare(xqspi->refclk);
1111 clk_dis_pclk:
1112 	clk_disable_unprepare(xqspi->pclk);
1113 remove_master:
1114 	spi_master_put(master);
1115 
1116 	return ret;
1117 }
1118 
1119 /**
1120  * zynqmp_qspi_remove:	Remove method for the QSPI driver
1121  * @pdev:	Pointer to the platform_device structure
1122  *
1123  * This function is called if a device is physically removed from the system or
1124  * if the driver module is being unloaded. It frees all resources allocated to
1125  * the device.
1126  *
1127  * Return:	0 Always
1128  */
1129 static int zynqmp_qspi_remove(struct platform_device *pdev)
1130 {
1131 	struct spi_master *master = platform_get_drvdata(pdev);
1132 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
1133 
1134 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
1135 	clk_disable_unprepare(xqspi->refclk);
1136 	clk_disable_unprepare(xqspi->pclk);
1137 	pm_runtime_set_suspended(&pdev->dev);
1138 	pm_runtime_disable(&pdev->dev);
1139 
1140 	spi_unregister_master(master);
1141 
1142 	return 0;
1143 }
1144 
1145 static const struct of_device_id zynqmp_qspi_of_match[] = {
1146 	{ .compatible = "xlnx,zynqmp-qspi-1.0", },
1147 	{ /* End of table */ }
1148 };
1149 
1150 MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
1151 
1152 static struct platform_driver zynqmp_qspi_driver = {
1153 	.probe = zynqmp_qspi_probe,
1154 	.remove = zynqmp_qspi_remove,
1155 	.driver = {
1156 		.name = "zynqmp-qspi",
1157 		.of_match_table = zynqmp_qspi_of_match,
1158 		.pm = &zynqmp_qspi_dev_pm_ops,
1159 	},
1160 };
1161 
1162 module_platform_driver(zynqmp_qspi_driver);
1163 
1164 MODULE_AUTHOR("Xilinx, Inc.");
1165 MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
1166 MODULE_LICENSE("GPL");
1167