xref: /linux/drivers/spi/spi-zynqmp-gqspi.c (revision 78beef629fd95be4ed853b2d37b832f766bd96ca)
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 	/* Dummy generic FIFO entry */
405 	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
406 
407 	/* Manually start the generic FIFO command */
408 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
409 			zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
410 			GQSPI_CFG_START_GEN_FIFO_MASK);
411 
412 	timeout = jiffies + msecs_to_jiffies(1000);
413 
414 	/* Wait until the generic FIFO command is empty */
415 	do {
416 		statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
417 
418 		if ((statusreg & GQSPI_ISR_GENFIFOEMPTY_MASK) &&
419 			(statusreg & GQSPI_ISR_TXEMPTY_MASK))
420 			break;
421 		else
422 			cpu_relax();
423 	} while (!time_after_eq(jiffies, timeout));
424 
425 	if (time_after_eq(jiffies, timeout))
426 		dev_err(xqspi->dev, "Chip select timed out\n");
427 }
428 
429 /**
430  * zynqmp_qspi_setup_transfer:	Configure QSPI controller for specified
431  *				transfer
432  * @qspi:	Pointer to the spi_device structure
433  * @transfer:	Pointer to the spi_transfer structure which provides
434  *		information about next transfer setup parameters
435  *
436  * Sets the operational mode of QSPI controller for the next QSPI transfer and
437  * sets the requested clock frequency.
438  *
439  * Return:	Always 0
440  *
441  * Note:
442  *	If the requested frequency is not an exact match with what can be
443  *	obtained using the pre-scalar value, the driver sets the clock
444  *	frequency which is lower than the requested frequency (maximum lower)
445  *	for the transfer.
446  *
447  *	If the requested frequency is higher or lower than that is supported
448  *	by the QSPI controller the driver will set the highest or lowest
449  *	frequency supported by controller.
450  */
451 static int zynqmp_qspi_setup_transfer(struct spi_device *qspi,
452 				      struct spi_transfer *transfer)
453 {
454 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
455 	ulong clk_rate;
456 	u32 config_reg, req_hz, baud_rate_val = 0;
457 
458 	if (transfer)
459 		req_hz = transfer->speed_hz;
460 	else
461 		req_hz = qspi->max_speed_hz;
462 
463 	/* Set the clock frequency */
464 	/* If req_hz == 0, default to lowest speed */
465 	clk_rate = clk_get_rate(xqspi->refclk);
466 
467 	while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
468 	       (clk_rate /
469 		(GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz)
470 		baud_rate_val++;
471 
472 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
473 
474 	/* Set the QSPI clock phase and clock polarity */
475 	config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
476 
477 	if (qspi->mode & SPI_CPHA)
478 		config_reg |= GQSPI_CFG_CLK_PHA_MASK;
479 	if (qspi->mode & SPI_CPOL)
480 		config_reg |= GQSPI_CFG_CLK_POL_MASK;
481 
482 	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
483 	config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
484 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
485 	return 0;
486 }
487 
488 /**
489  * zynqmp_qspi_setup:	Configure the QSPI controller
490  * @qspi:	Pointer to the spi_device structure
491  *
492  * Sets the operational mode of QSPI controller for the next QSPI transfer,
493  * baud rate and divisor value to setup the requested qspi clock.
494  *
495  * Return:	0 on success; error value otherwise.
496  */
497 static int zynqmp_qspi_setup(struct spi_device *qspi)
498 {
499 	if (qspi->master->busy)
500 		return -EBUSY;
501 	return 0;
502 }
503 
504 /**
505  * zynqmp_qspi_filltxfifo:	Fills the TX FIFO as long as there is room in
506  *				the FIFO or the bytes required to be
507  *				transmitted.
508  * @xqspi:	Pointer to the zynqmp_qspi structure
509  * @size:	Number of bytes to be copied from TX buffer to TX FIFO
510  */
511 static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
512 {
513 	u32 count = 0, intermediate;
514 
515 	while ((xqspi->bytes_to_transfer > 0) && (count < size)) {
516 		memcpy(&intermediate, xqspi->txbuf, 4);
517 		zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
518 
519 		if (xqspi->bytes_to_transfer >= 4) {
520 			xqspi->txbuf += 4;
521 			xqspi->bytes_to_transfer -= 4;
522 		} else {
523 			xqspi->txbuf += xqspi->bytes_to_transfer;
524 			xqspi->bytes_to_transfer = 0;
525 		}
526 		count++;
527 	}
528 }
529 
530 /**
531  * zynqmp_qspi_readrxfifo:	Fills the RX FIFO as long as there is room in
532  *				the FIFO.
533  * @xqspi:	Pointer to the zynqmp_qspi structure
534  * @size:	Number of bytes to be copied from RX buffer to RX FIFO
535  */
536 static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
537 {
538 	ulong data;
539 	int count = 0;
540 
541 	while ((count < size) && (xqspi->bytes_to_receive > 0)) {
542 		if (xqspi->bytes_to_receive >= 4) {
543 			(*(u32 *) xqspi->rxbuf) =
544 			zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
545 			xqspi->rxbuf += 4;
546 			xqspi->bytes_to_receive -= 4;
547 			count += 4;
548 		} else {
549 			data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
550 			count += xqspi->bytes_to_receive;
551 			zynqmp_qspi_copy_read_data(xqspi, data,
552 						   xqspi->bytes_to_receive);
553 			xqspi->bytes_to_receive = 0;
554 		}
555 	}
556 }
557 
558 /**
559  * zynqmp_process_dma_irq:	Handler for DMA done interrupt of QSPI
560  *				controller
561  * @xqspi:	zynqmp_qspi instance pointer
562  *
563  * This function handles DMA interrupt only.
564  */
565 static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
566 {
567 	u32 config_reg, genfifoentry;
568 
569 	dma_unmap_single(xqspi->dev, xqspi->dma_addr,
570 				xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
571 	xqspi->rxbuf += xqspi->dma_rx_bytes;
572 	xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
573 	xqspi->dma_rx_bytes = 0;
574 
575 	/* Disabling the DMA interrupts */
576 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST,
577 					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
578 
579 	if (xqspi->bytes_to_receive > 0) {
580 		/* Switch to IO mode,for remaining bytes to receive */
581 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
582 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
583 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
584 
585 		/* Initiate the transfer of remaining bytes */
586 		genfifoentry = xqspi->genfifoentry;
587 		genfifoentry |= xqspi->bytes_to_receive;
588 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
589 
590 		/* Dummy generic FIFO entry */
591 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
592 
593 		/* Manual start */
594 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
595 			(zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
596 			GQSPI_CFG_START_GEN_FIFO_MASK));
597 
598 		/* Enable the RX interrupts for IO mode */
599 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
600 				GQSPI_IER_GENFIFOEMPTY_MASK |
601 				GQSPI_IER_RXNEMPTY_MASK |
602 				GQSPI_IER_RXEMPTY_MASK);
603 	}
604 }
605 
606 /**
607  * zynqmp_qspi_irq:	Interrupt service routine of the QSPI controller
608  * @irq:	IRQ number
609  * @dev_id:	Pointer to the xqspi structure
610  *
611  * This function handles TX empty only.
612  * On TX empty interrupt this function reads the received data from RX FIFO
613  * and fills the TX FIFO if there is any data remaining to be transferred.
614  *
615  * Return:	IRQ_HANDLED when interrupt is handled
616  *		IRQ_NONE otherwise.
617  */
618 static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
619 {
620 	struct spi_master *master = dev_id;
621 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
622 	int ret = IRQ_NONE;
623 	u32 status, mask, dma_status = 0;
624 
625 	status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
626 	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status);
627 	mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST)));
628 
629 	/* Read and clear DMA status */
630 	if (xqspi->mode == GQSPI_MODE_DMA) {
631 		dma_status =
632 			zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST);
633 		zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
634 								dma_status);
635 	}
636 
637 	if (mask & GQSPI_ISR_TXNOT_FULL_MASK) {
638 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
639 		ret = IRQ_HANDLED;
640 	}
641 
642 	if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) {
643 		zynqmp_process_dma_irq(xqspi);
644 		ret = IRQ_HANDLED;
645 	} else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
646 			(mask & GQSPI_IER_GENFIFOEMPTY_MASK)) {
647 		zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
648 		ret = IRQ_HANDLED;
649 	}
650 
651 	if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0)
652 			&& ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
653 		zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK);
654 		spi_finalize_current_transfer(master);
655 		ret = IRQ_HANDLED;
656 	}
657 	return ret;
658 }
659 
660 /**
661  * zynqmp_qspi_selectspimode:	Selects SPI mode - x1 or x2 or x4.
662  * @xqspi:	xqspi is a pointer to the GQSPI instance
663  * @spimode:	spimode - SPI or DUAL or QUAD.
664  * Return:	Mask to set desired SPI mode in GENFIFO entry.
665  */
666 static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi,
667 						u8 spimode)
668 {
669 	u32 mask = 0;
670 
671 	switch (spimode) {
672 	case GQSPI_SELECT_MODE_DUALSPI:
673 		mask = GQSPI_GENFIFO_MODE_DUALSPI;
674 		break;
675 	case GQSPI_SELECT_MODE_QUADSPI:
676 		mask = GQSPI_GENFIFO_MODE_QUADSPI;
677 		break;
678 	case GQSPI_SELECT_MODE_SPI:
679 		mask = GQSPI_GENFIFO_MODE_SPI;
680 		break;
681 	default:
682 		dev_warn(xqspi->dev, "Invalid SPI mode\n");
683 	}
684 
685 	return mask;
686 }
687 
688 /**
689  * zynq_qspi_setuprxdma:	This function sets up the RX DMA operation
690  * @xqspi:	xqspi is a pointer to the GQSPI instance.
691  */
692 static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
693 {
694 	u32 rx_bytes, rx_rem, config_reg;
695 	dma_addr_t addr;
696 	u64 dma_align =  (u64)(uintptr_t)xqspi->rxbuf;
697 
698 	if ((xqspi->bytes_to_receive < 8) ||
699 		((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
700 		/* Setting to IO mode */
701 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
702 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
703 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
704 		xqspi->mode = GQSPI_MODE_IO;
705 		xqspi->dma_rx_bytes = 0;
706 		return;
707 	}
708 
709 	rx_rem = xqspi->bytes_to_receive % 4;
710 	rx_bytes = (xqspi->bytes_to_receive - rx_rem);
711 
712 	addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
713 						rx_bytes, DMA_FROM_DEVICE);
714 	if (dma_mapping_error(xqspi->dev, addr))
715 		dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
716 
717 	xqspi->dma_rx_bytes = rx_bytes;
718 	xqspi->dma_addr = addr;
719 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
720 				(u32)(addr & 0xffffffff));
721 	addr = ((addr >> 16) >> 16);
722 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
723 				((u32)addr) & 0xfff);
724 
725 	/* Enabling the DMA mode */
726 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
727 	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
728 	config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
729 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
730 
731 	/* Switch to DMA mode */
732 	xqspi->mode = GQSPI_MODE_DMA;
733 
734 	/* Write the number of bytes to transfer */
735 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
736 }
737 
738 /**
739  * zynqmp_qspi_txrxsetup:	This function checks the TX/RX buffers in
740  *				the transfer and sets up the GENFIFO entries,
741  *				TX FIFO as required.
742  * @xqspi:	xqspi is a pointer to the GQSPI instance.
743  * @transfer:	It is a pointer to the structure containing transfer data.
744  * @genfifoentry:	genfifoentry is pointer to the variable in which
745  *			GENFIFO	mask is returned to calling function
746  */
747 static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi,
748 				  struct spi_transfer *transfer,
749 				  u32 *genfifoentry)
750 {
751 	u32 config_reg;
752 
753 	/* Transmit */
754 	if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) {
755 		/* Setup data to be TXed */
756 		*genfifoentry &= ~GQSPI_GENFIFO_RX;
757 		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
758 		*genfifoentry |= GQSPI_GENFIFO_TX;
759 		*genfifoentry |=
760 			zynqmp_qspi_selectspimode(xqspi, transfer->tx_nbits);
761 		xqspi->bytes_to_transfer = transfer->len;
762 		if (xqspi->mode == GQSPI_MODE_DMA) {
763 			config_reg = zynqmp_gqspi_read(xqspi,
764 							GQSPI_CONFIG_OFST);
765 			config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
766 			zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
767 								config_reg);
768 			xqspi->mode = GQSPI_MODE_IO;
769 		}
770 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
771 		/* Discard RX data */
772 		xqspi->bytes_to_receive = 0;
773 	} else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) {
774 		/* Receive */
775 
776 		/* TX auto fill */
777 		*genfifoentry &= ~GQSPI_GENFIFO_TX;
778 		/* Setup RX */
779 		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
780 		*genfifoentry |= GQSPI_GENFIFO_RX;
781 		*genfifoentry |=
782 			zynqmp_qspi_selectspimode(xqspi, transfer->rx_nbits);
783 		xqspi->bytes_to_transfer = 0;
784 		xqspi->bytes_to_receive = transfer->len;
785 		zynq_qspi_setuprxdma(xqspi);
786 	}
787 }
788 
789 /**
790  * zynqmp_qspi_start_transfer:	Initiates the QSPI transfer
791  * @master:	Pointer to the spi_master structure which provides
792  *		information about the controller.
793  * @qspi:	Pointer to the spi_device structure
794  * @transfer:	Pointer to the spi_transfer structure which provide information
795  *		about next transfer parameters
796  *
797  * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
798  * transfer to be completed.
799  *
800  * Return:	Number of bytes transferred in the last transfer
801  */
802 static int zynqmp_qspi_start_transfer(struct spi_master *master,
803 				      struct spi_device *qspi,
804 				      struct spi_transfer *transfer)
805 {
806 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
807 	u32 genfifoentry = 0x0, transfer_len;
808 
809 	xqspi->txbuf = transfer->tx_buf;
810 	xqspi->rxbuf = transfer->rx_buf;
811 
812 	zynqmp_qspi_setup_transfer(qspi, transfer);
813 
814 	genfifoentry |= xqspi->genfifocs;
815 	genfifoentry |= xqspi->genfifobus;
816 
817 	zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry);
818 
819 	if (xqspi->mode == GQSPI_MODE_DMA)
820 		transfer_len = xqspi->dma_rx_bytes;
821 	else
822 		transfer_len = transfer->len;
823 
824 	xqspi->genfifoentry = genfifoentry;
825 	if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {
826 		genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
827 		genfifoentry |= transfer_len;
828 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
829 	} else {
830 		int tempcount = transfer_len;
831 		u32 exponent = 8;	/* 2^8 = 256 */
832 		u8 imm_data = tempcount & 0xFF;
833 
834 		tempcount &= ~(tempcount & 0xFF);
835 		/* Immediate entry */
836 		if (tempcount != 0) {
837 			/* Exponent entries */
838 			genfifoentry |= GQSPI_GENFIFO_EXP;
839 			while (tempcount != 0) {
840 				if (tempcount & GQSPI_GENFIFO_EXP_START) {
841 					genfifoentry &=
842 					    ~GQSPI_GENFIFO_IMM_DATA_MASK;
843 					genfifoentry |= exponent;
844 					zynqmp_gqspi_write(xqspi,
845 							   GQSPI_GEN_FIFO_OFST,
846 							   genfifoentry);
847 				}
848 				tempcount = tempcount >> 1;
849 				exponent++;
850 			}
851 		}
852 		if (imm_data != 0) {
853 			genfifoentry &= ~GQSPI_GENFIFO_EXP;
854 			genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
855 			genfifoentry |= (u8) (imm_data & 0xFF);
856 			zynqmp_gqspi_write(xqspi,
857 					   GQSPI_GEN_FIFO_OFST, genfifoentry);
858 		}
859 	}
860 
861 	if ((xqspi->mode == GQSPI_MODE_IO) &&
862 			(xqspi->rxbuf != NULL)) {
863 		/* Dummy generic FIFO entry */
864 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
865 	}
866 
867 	/* Since we are using manual mode */
868 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
869 			   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
870 			   GQSPI_CFG_START_GEN_FIFO_MASK);
871 
872 	if (xqspi->txbuf != NULL)
873 		/* Enable interrupts for TX */
874 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
875 				   GQSPI_IER_TXEMPTY_MASK |
876 					GQSPI_IER_GENFIFOEMPTY_MASK |
877 					GQSPI_IER_TXNOT_FULL_MASK);
878 
879 	if (xqspi->rxbuf != NULL) {
880 		/* Enable interrupts for RX */
881 		if (xqspi->mode == GQSPI_MODE_DMA) {
882 			/* Enable DMA interrupts */
883 			zynqmp_gqspi_write(xqspi,
884 					GQSPI_QSPIDMA_DST_I_EN_OFST,
885 					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
886 		} else {
887 			zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
888 					GQSPI_IER_GENFIFOEMPTY_MASK |
889 					GQSPI_IER_RXNEMPTY_MASK |
890 					GQSPI_IER_RXEMPTY_MASK);
891 		}
892 	}
893 
894 	return transfer->len;
895 }
896 
897 /**
898  * zynqmp_qspi_suspend:	Suspend method for the QSPI driver
899  * @_dev:	Address of the platform_device structure
900  *
901  * This function stops the QSPI driver queue and disables the QSPI controller
902  *
903  * Return:	Always 0
904  */
905 static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
906 {
907 	struct spi_master *master = dev_get_drvdata(dev);
908 
909 	spi_master_suspend(master);
910 
911 	zynqmp_unprepare_transfer_hardware(master);
912 
913 	return 0;
914 }
915 
916 /**
917  * zynqmp_qspi_resume:	Resume method for the QSPI driver
918  * @dev:	Address of the platform_device structure
919  *
920  * The function starts the QSPI driver queue and initializes the QSPI
921  * controller
922  *
923  * Return:	0 on success; error value otherwise
924  */
925 static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
926 {
927 	struct spi_master *master = dev_get_drvdata(dev);
928 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
929 	int ret = 0;
930 
931 	ret = clk_enable(xqspi->pclk);
932 	if (ret) {
933 		dev_err(dev, "Cannot enable APB clock.\n");
934 		return ret;
935 	}
936 
937 	ret = clk_enable(xqspi->refclk);
938 	if (ret) {
939 		dev_err(dev, "Cannot enable device clock.\n");
940 		clk_disable(xqspi->pclk);
941 		return ret;
942 	}
943 
944 	spi_master_resume(master);
945 
946 	clk_disable(xqspi->refclk);
947 	clk_disable(xqspi->pclk);
948 	return 0;
949 }
950 
951 /**
952  * zynqmp_runtime_suspend - Runtime suspend method for the SPI driver
953  * @dev:	Address of the platform_device structure
954  *
955  * This function disables the clocks
956  *
957  * Return:	Always 0
958  */
959 static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
960 {
961 	struct spi_master *master = dev_get_drvdata(dev);
962 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
963 
964 	clk_disable(xqspi->refclk);
965 	clk_disable(xqspi->pclk);
966 
967 	return 0;
968 }
969 
970 /**
971  * zynqmp_runtime_resume - Runtime resume method for the SPI driver
972  * @dev:	Address of the platform_device structure
973  *
974  * This function enables the clocks
975  *
976  * Return:	0 on success and error value on error
977  */
978 static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
979 {
980 	struct spi_master *master = dev_get_drvdata(dev);
981 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
982 	int ret;
983 
984 	ret = clk_enable(xqspi->pclk);
985 	if (ret) {
986 		dev_err(dev, "Cannot enable APB clock.\n");
987 		return ret;
988 	}
989 
990 	ret = clk_enable(xqspi->refclk);
991 	if (ret) {
992 		dev_err(dev, "Cannot enable device clock.\n");
993 		clk_disable(xqspi->pclk);
994 		return ret;
995 	}
996 
997 	return 0;
998 }
999 
1000 static const struct dev_pm_ops zynqmp_qspi_dev_pm_ops = {
1001 	SET_RUNTIME_PM_OPS(zynqmp_runtime_suspend,
1002 			   zynqmp_runtime_resume, NULL)
1003 	SET_SYSTEM_SLEEP_PM_OPS(zynqmp_qspi_suspend, zynqmp_qspi_resume)
1004 };
1005 
1006 /**
1007  * zynqmp_qspi_probe:	Probe method for the QSPI driver
1008  * @pdev:	Pointer to the platform_device structure
1009  *
1010  * This function initializes the driver data structures and the hardware.
1011  *
1012  * Return:	0 on success; error value otherwise
1013  */
1014 static int zynqmp_qspi_probe(struct platform_device *pdev)
1015 {
1016 	int ret = 0;
1017 	struct spi_master *master;
1018 	struct zynqmp_qspi *xqspi;
1019 	struct device *dev = &pdev->dev;
1020 
1021 	eemi_ops = zynqmp_pm_get_eemi_ops();
1022 	if (IS_ERR(eemi_ops))
1023 		return PTR_ERR(eemi_ops);
1024 
1025 	master = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
1026 	if (!master)
1027 		return -ENOMEM;
1028 
1029 	xqspi = spi_master_get_devdata(master);
1030 	master->dev.of_node = pdev->dev.of_node;
1031 	platform_set_drvdata(pdev, master);
1032 
1033 	xqspi->regs = devm_platform_ioremap_resource(pdev, 0);
1034 	if (IS_ERR(xqspi->regs)) {
1035 		ret = PTR_ERR(xqspi->regs);
1036 		goto remove_master;
1037 	}
1038 
1039 	xqspi->dev = dev;
1040 	xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
1041 	if (IS_ERR(xqspi->pclk)) {
1042 		dev_err(dev, "pclk clock not found.\n");
1043 		ret = PTR_ERR(xqspi->pclk);
1044 		goto remove_master;
1045 	}
1046 
1047 	ret = clk_prepare_enable(xqspi->pclk);
1048 	if (ret) {
1049 		dev_err(dev, "Unable to enable APB clock.\n");
1050 		goto remove_master;
1051 	}
1052 
1053 	xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
1054 	if (IS_ERR(xqspi->refclk)) {
1055 		dev_err(dev, "ref_clk clock not found.\n");
1056 		ret = PTR_ERR(xqspi->refclk);
1057 		goto clk_dis_pclk;
1058 	}
1059 
1060 	ret = clk_prepare_enable(xqspi->refclk);
1061 	if (ret) {
1062 		dev_err(dev, "Unable to enable device clock.\n");
1063 		goto clk_dis_pclk;
1064 	}
1065 
1066 	pm_runtime_use_autosuspend(&pdev->dev);
1067 	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1068 	pm_runtime_set_active(&pdev->dev);
1069 	pm_runtime_enable(&pdev->dev);
1070 	/* QSPI controller initializations */
1071 	zynqmp_qspi_init_hw(xqspi);
1072 
1073 	pm_runtime_mark_last_busy(&pdev->dev);
1074 	pm_runtime_put_autosuspend(&pdev->dev);
1075 	xqspi->irq = platform_get_irq(pdev, 0);
1076 	if (xqspi->irq <= 0) {
1077 		ret = -ENXIO;
1078 		goto clk_dis_all;
1079 	}
1080 	ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
1081 			       0, pdev->name, master);
1082 	if (ret != 0) {
1083 		ret = -ENXIO;
1084 		dev_err(dev, "request_irq failed\n");
1085 		goto clk_dis_all;
1086 	}
1087 
1088 	master->num_chipselect = GQSPI_DEFAULT_NUM_CS;
1089 
1090 	master->setup = zynqmp_qspi_setup;
1091 	master->set_cs = zynqmp_qspi_chipselect;
1092 	master->transfer_one = zynqmp_qspi_start_transfer;
1093 	master->prepare_transfer_hardware = zynqmp_prepare_transfer_hardware;
1094 	master->unprepare_transfer_hardware =
1095 					zynqmp_unprepare_transfer_hardware;
1096 	master->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
1097 	master->bits_per_word_mask = SPI_BPW_MASK(8);
1098 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
1099 			    SPI_TX_DUAL | SPI_TX_QUAD;
1100 
1101 	if (master->dev.parent == NULL)
1102 		master->dev.parent = &master->dev;
1103 
1104 	ret = spi_register_master(master);
1105 	if (ret)
1106 		goto clk_dis_all;
1107 
1108 	return 0;
1109 
1110 clk_dis_all:
1111 	pm_runtime_set_suspended(&pdev->dev);
1112 	pm_runtime_disable(&pdev->dev);
1113 	clk_disable_unprepare(xqspi->refclk);
1114 clk_dis_pclk:
1115 	clk_disable_unprepare(xqspi->pclk);
1116 remove_master:
1117 	spi_master_put(master);
1118 
1119 	return ret;
1120 }
1121 
1122 /**
1123  * zynqmp_qspi_remove:	Remove method for the QSPI driver
1124  * @pdev:	Pointer to the platform_device structure
1125  *
1126  * This function is called if a device is physically removed from the system or
1127  * if the driver module is being unloaded. It frees all resources allocated to
1128  * the device.
1129  *
1130  * Return:	0 Always
1131  */
1132 static int zynqmp_qspi_remove(struct platform_device *pdev)
1133 {
1134 	struct spi_master *master = platform_get_drvdata(pdev);
1135 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
1136 
1137 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
1138 	clk_disable_unprepare(xqspi->refclk);
1139 	clk_disable_unprepare(xqspi->pclk);
1140 	pm_runtime_set_suspended(&pdev->dev);
1141 	pm_runtime_disable(&pdev->dev);
1142 
1143 	spi_unregister_master(master);
1144 
1145 	return 0;
1146 }
1147 
1148 static const struct of_device_id zynqmp_qspi_of_match[] = {
1149 	{ .compatible = "xlnx,zynqmp-qspi-1.0", },
1150 	{ /* End of table */ }
1151 };
1152 
1153 MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
1154 
1155 static struct platform_driver zynqmp_qspi_driver = {
1156 	.probe = zynqmp_qspi_probe,
1157 	.remove = zynqmp_qspi_remove,
1158 	.driver = {
1159 		.name = "zynqmp-qspi",
1160 		.of_match_table = zynqmp_qspi_of_match,
1161 		.pm = &zynqmp_qspi_dev_pm_ops,
1162 	},
1163 };
1164 
1165 module_platform_driver(zynqmp_qspi_driver);
1166 
1167 MODULE_AUTHOR("Xilinx, Inc.");
1168 MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
1169 MODULE_LICENSE("GPL");
1170