1 /*
2  * Xilinx Zynq UltraScale+ MPSoC Quad-SPI (QSPI) controller driver
3  * (master mode only)
4  *
5  * Copyright (C) 2009 - 2015 Xilinx, Inc.
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License version 2 as published
9  * by the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/delay.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/dmaengine.h>
17 #include <linux/firmware/xlnx-zynqmp.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/of_irq.h>
22 #include <linux/of_address.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/spi/spi.h>
26 #include <linux/spinlock.h>
27 #include <linux/workqueue.h>
28 
29 /* Generic QSPI register offsets */
30 #define GQSPI_CONFIG_OFST		0x00000100
31 #define GQSPI_ISR_OFST			0x00000104
32 #define GQSPI_IDR_OFST			0x0000010C
33 #define GQSPI_IER_OFST			0x00000108
34 #define GQSPI_IMASK_OFST		0x00000110
35 #define GQSPI_EN_OFST			0x00000114
36 #define GQSPI_TXD_OFST			0x0000011C
37 #define GQSPI_RXD_OFST			0x00000120
38 #define GQSPI_TX_THRESHOLD_OFST		0x00000128
39 #define GQSPI_RX_THRESHOLD_OFST		0x0000012C
40 #define GQSPI_LPBK_DLY_ADJ_OFST		0x00000138
41 #define GQSPI_GEN_FIFO_OFST		0x00000140
42 #define GQSPI_SEL_OFST			0x00000144
43 #define GQSPI_GF_THRESHOLD_OFST		0x00000150
44 #define GQSPI_FIFO_CTRL_OFST		0x0000014C
45 #define GQSPI_QSPIDMA_DST_CTRL_OFST	0x0000080C
46 #define GQSPI_QSPIDMA_DST_SIZE_OFST	0x00000804
47 #define GQSPI_QSPIDMA_DST_STS_OFST	0x00000808
48 #define GQSPI_QSPIDMA_DST_I_STS_OFST	0x00000814
49 #define GQSPI_QSPIDMA_DST_I_EN_OFST	0x00000818
50 #define GQSPI_QSPIDMA_DST_I_DIS_OFST	0x0000081C
51 #define GQSPI_QSPIDMA_DST_I_MASK_OFST	0x00000820
52 #define GQSPI_QSPIDMA_DST_ADDR_OFST	0x00000800
53 #define GQSPI_QSPIDMA_DST_ADDR_MSB_OFST 0x00000828
54 
55 /* GQSPI register bit masks */
56 #define GQSPI_SEL_MASK				0x00000001
57 #define GQSPI_EN_MASK				0x00000001
58 #define GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK	0x00000020
59 #define GQSPI_ISR_WR_TO_CLR_MASK		0x00000002
60 #define GQSPI_IDR_ALL_MASK			0x00000FBE
61 #define GQSPI_CFG_MODE_EN_MASK			0xC0000000
62 #define GQSPI_CFG_GEN_FIFO_START_MODE_MASK	0x20000000
63 #define GQSPI_CFG_ENDIAN_MASK			0x04000000
64 #define GQSPI_CFG_EN_POLL_TO_MASK		0x00100000
65 #define GQSPI_CFG_WP_HOLD_MASK			0x00080000
66 #define GQSPI_CFG_BAUD_RATE_DIV_MASK		0x00000038
67 #define GQSPI_CFG_CLK_PHA_MASK			0x00000004
68 #define GQSPI_CFG_CLK_POL_MASK			0x00000002
69 #define GQSPI_CFG_START_GEN_FIFO_MASK		0x10000000
70 #define GQSPI_GENFIFO_IMM_DATA_MASK		0x000000FF
71 #define GQSPI_GENFIFO_DATA_XFER			0x00000100
72 #define GQSPI_GENFIFO_EXP			0x00000200
73 #define GQSPI_GENFIFO_MODE_SPI			0x00000400
74 #define GQSPI_GENFIFO_MODE_DUALSPI		0x00000800
75 #define GQSPI_GENFIFO_MODE_QUADSPI		0x00000C00
76 #define GQSPI_GENFIFO_MODE_MASK			0x00000C00
77 #define GQSPI_GENFIFO_CS_LOWER			0x00001000
78 #define GQSPI_GENFIFO_CS_UPPER			0x00002000
79 #define GQSPI_GENFIFO_BUS_LOWER			0x00004000
80 #define GQSPI_GENFIFO_BUS_UPPER			0x00008000
81 #define GQSPI_GENFIFO_BUS_BOTH			0x0000C000
82 #define GQSPI_GENFIFO_BUS_MASK			0x0000C000
83 #define GQSPI_GENFIFO_TX			0x00010000
84 #define GQSPI_GENFIFO_RX			0x00020000
85 #define GQSPI_GENFIFO_STRIPE			0x00040000
86 #define GQSPI_GENFIFO_POLL			0x00080000
87 #define GQSPI_GENFIFO_EXP_START			0x00000100
88 #define GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK	0x00000004
89 #define GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK	0x00000002
90 #define GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK	0x00000001
91 #define GQSPI_ISR_RXEMPTY_MASK			0x00000800
92 #define GQSPI_ISR_GENFIFOFULL_MASK		0x00000400
93 #define GQSPI_ISR_GENFIFONOT_FULL_MASK		0x00000200
94 #define GQSPI_ISR_TXEMPTY_MASK			0x00000100
95 #define GQSPI_ISR_GENFIFOEMPTY_MASK		0x00000080
96 #define GQSPI_ISR_RXFULL_MASK			0x00000020
97 #define GQSPI_ISR_RXNEMPTY_MASK			0x00000010
98 #define GQSPI_ISR_TXFULL_MASK			0x00000008
99 #define GQSPI_ISR_TXNOT_FULL_MASK		0x00000004
100 #define GQSPI_ISR_POLL_TIME_EXPIRE_MASK		0x00000002
101 #define GQSPI_IER_TXNOT_FULL_MASK		0x00000004
102 #define GQSPI_IER_RXEMPTY_MASK			0x00000800
103 #define GQSPI_IER_POLL_TIME_EXPIRE_MASK		0x00000002
104 #define GQSPI_IER_RXNEMPTY_MASK			0x00000010
105 #define GQSPI_IER_GENFIFOEMPTY_MASK		0x00000080
106 #define GQSPI_IER_TXEMPTY_MASK			0x00000100
107 #define GQSPI_QSPIDMA_DST_INTR_ALL_MASK		0x000000FE
108 #define GQSPI_QSPIDMA_DST_STS_WTC		0x0000E000
109 #define GQSPI_CFG_MODE_EN_DMA_MASK		0x80000000
110 #define GQSPI_ISR_IDR_MASK			0x00000994
111 #define GQSPI_QSPIDMA_DST_I_EN_DONE_MASK	0x00000002
112 #define GQSPI_QSPIDMA_DST_I_STS_DONE_MASK	0x00000002
113 #define GQSPI_IRQ_MASK				0x00000980
114 
115 #define GQSPI_CFG_BAUD_RATE_DIV_SHIFT		3
116 #define GQSPI_GENFIFO_CS_SETUP			0x4
117 #define GQSPI_GENFIFO_CS_HOLD			0x3
118 #define GQSPI_TXD_DEPTH				64
119 #define GQSPI_RX_FIFO_THRESHOLD			32
120 #define GQSPI_RX_FIFO_FILL	(GQSPI_RX_FIFO_THRESHOLD * 4)
121 #define GQSPI_TX_FIFO_THRESHOLD_RESET_VAL	32
122 #define GQSPI_TX_FIFO_FILL	(GQSPI_TXD_DEPTH -\
123 				GQSPI_TX_FIFO_THRESHOLD_RESET_VAL)
124 #define GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL	0X10
125 #define GQSPI_QSPIDMA_DST_CTRL_RESET_VAL	0x803FFA00
126 #define GQSPI_SELECT_FLASH_CS_LOWER		0x1
127 #define GQSPI_SELECT_FLASH_CS_UPPER		0x2
128 #define GQSPI_SELECT_FLASH_CS_BOTH		0x3
129 #define GQSPI_SELECT_FLASH_BUS_LOWER		0x1
130 #define GQSPI_SELECT_FLASH_BUS_UPPER		0x2
131 #define GQSPI_SELECT_FLASH_BUS_BOTH		0x3
132 #define GQSPI_BAUD_DIV_MAX	7	/* Baud rate divisor maximum */
133 #define GQSPI_BAUD_DIV_SHIFT	2	/* Baud rate divisor shift */
134 #define GQSPI_SELECT_MODE_SPI		0x1
135 #define GQSPI_SELECT_MODE_DUALSPI	0x2
136 #define GQSPI_SELECT_MODE_QUADSPI	0x4
137 #define GQSPI_DMA_UNALIGN		0x3
138 #define GQSPI_DEFAULT_NUM_CS	1	/* Default number of chip selects */
139 
140 #define SPI_AUTOSUSPEND_TIMEOUT		3000
141 enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
142 static const struct zynqmp_eemi_ops *eemi_ops;
143 
144 /**
145  * struct zynqmp_qspi - Defines qspi driver instance
146  * @regs:		Virtual address of the QSPI controller registers
147  * @refclk:		Pointer to the peripheral clock
148  * @pclk:		Pointer to the APB clock
149  * @irq:		IRQ number
150  * @dev:		Pointer to struct device
151  * @txbuf:		Pointer to the TX buffer
152  * @rxbuf:		Pointer to the RX buffer
153  * @bytes_to_transfer:	Number of bytes left to transfer
154  * @bytes_to_receive:	Number of bytes left to receive
155  * @genfifocs:		Used for chip select
156  * @genfifobus:		Used to select the upper or lower bus
157  * @dma_rx_bytes:	Remaining bytes to receive by DMA mode
158  * @dma_addr:		DMA address after mapping the kernel buffer
159  * @genfifoentry:	Used for storing the genfifoentry instruction.
160  * @mode:		Defines the mode in which QSPI is operating
161  */
162 struct zynqmp_qspi {
163 	void __iomem *regs;
164 	struct clk *refclk;
165 	struct clk *pclk;
166 	int irq;
167 	struct device *dev;
168 	const void *txbuf;
169 	void *rxbuf;
170 	int bytes_to_transfer;
171 	int bytes_to_receive;
172 	u32 genfifocs;
173 	u32 genfifobus;
174 	u32 dma_rx_bytes;
175 	dma_addr_t dma_addr;
176 	u32 genfifoentry;
177 	enum mode_type mode;
178 };
179 
180 /**
181  * zynqmp_gqspi_read:	For GQSPI controller read operation
182  * @xqspi:	Pointer to the zynqmp_qspi structure
183  * @offset:	Offset from where to read
184  */
185 static u32 zynqmp_gqspi_read(struct zynqmp_qspi *xqspi, u32 offset)
186 {
187 	return readl_relaxed(xqspi->regs + offset);
188 }
189 
190 /**
191  * zynqmp_gqspi_write:	For GQSPI controller write operation
192  * @xqspi:	Pointer to the zynqmp_qspi structure
193  * @offset:	Offset where to write
194  * @val:	Value to be written
195  */
196 static inline void zynqmp_gqspi_write(struct zynqmp_qspi *xqspi, u32 offset,
197 				      u32 val)
198 {
199 	writel_relaxed(val, (xqspi->regs + offset));
200 }
201 
202 /**
203  * zynqmp_gqspi_selectslave:	For selection of slave device
204  * @instanceptr:	Pointer to the zynqmp_qspi structure
205  * @flashcs:	For chip select
206  * @flashbus:	To check which bus is selected- upper or lower
207  */
208 static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
209 				     u8 slavecs, u8 slavebus)
210 {
211 	/*
212 	 * Bus and CS lines selected here will be updated in the instance and
213 	 * used for subsequent GENFIFO entries during transfer.
214 	 */
215 
216 	/* Choose slave select line */
217 	switch (slavecs) {
218 	case GQSPI_SELECT_FLASH_CS_BOTH:
219 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER |
220 			GQSPI_GENFIFO_CS_UPPER;
221 		break;
222 	case GQSPI_SELECT_FLASH_CS_UPPER:
223 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_UPPER;
224 		break;
225 	case GQSPI_SELECT_FLASH_CS_LOWER:
226 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER;
227 		break;
228 	default:
229 		dev_warn(instanceptr->dev, "Invalid slave select\n");
230 	}
231 
232 	/* Choose the bus */
233 	switch (slavebus) {
234 	case GQSPI_SELECT_FLASH_BUS_BOTH:
235 		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER |
236 			GQSPI_GENFIFO_BUS_UPPER;
237 		break;
238 	case GQSPI_SELECT_FLASH_BUS_UPPER:
239 		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_UPPER;
240 		break;
241 	case GQSPI_SELECT_FLASH_BUS_LOWER:
242 		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER;
243 		break;
244 	default:
245 		dev_warn(instanceptr->dev, "Invalid slave bus\n");
246 	}
247 }
248 
249 /**
250  * zynqmp_qspi_init_hw:	Initialize the hardware
251  * @xqspi:	Pointer to the zynqmp_qspi structure
252  *
253  * The default settings of the QSPI controller's configurable parameters on
254  * reset are
255  *	- Master mode
256  *	- TX threshold set to 1
257  *	- RX threshold set to 1
258  *	- Flash memory interface mode enabled
259  * This function performs the following actions
260  *	- Disable and clear all the interrupts
261  *	- Enable manual slave select
262  *	- Enable manual start
263  *	- Deselect all the chip select lines
264  *	- Set the little endian mode of TX FIFO and
265  *	- Enable the QSPI controller
266  */
267 static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
268 {
269 	u32 config_reg;
270 
271 	/* Select the GQSPI mode */
272 	zynqmp_gqspi_write(xqspi, GQSPI_SEL_OFST, GQSPI_SEL_MASK);
273 	/* Clear and disable interrupts */
274 	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST,
275 			   zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST) |
276 			   GQSPI_ISR_WR_TO_CLR_MASK);
277 	/* Clear the DMA STS */
278 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
279 			   zynqmp_gqspi_read(xqspi,
280 					     GQSPI_QSPIDMA_DST_I_STS_OFST));
281 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_STS_OFST,
282 			   zynqmp_gqspi_read(xqspi,
283 					     GQSPI_QSPIDMA_DST_STS_OFST) |
284 					     GQSPI_QSPIDMA_DST_STS_WTC);
285 	zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_IDR_ALL_MASK);
286 	zynqmp_gqspi_write(xqspi,
287 			   GQSPI_QSPIDMA_DST_I_DIS_OFST,
288 			   GQSPI_QSPIDMA_DST_INTR_ALL_MASK);
289 	/* Disable the GQSPI */
290 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
291 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
292 	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
293 	/* Manual start */
294 	config_reg |= GQSPI_CFG_GEN_FIFO_START_MODE_MASK;
295 	/* Little endian by default */
296 	config_reg &= ~GQSPI_CFG_ENDIAN_MASK;
297 	/* Disable poll time out */
298 	config_reg &= ~GQSPI_CFG_EN_POLL_TO_MASK;
299 	/* Set hold bit */
300 	config_reg |= GQSPI_CFG_WP_HOLD_MASK;
301 	/* Clear pre-scalar by default */
302 	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
303 	/* CPHA 0 */
304 	config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
305 	/* CPOL 0 */
306 	config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
307 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
308 
309 	/* Clear the TX and RX FIFO */
310 	zynqmp_gqspi_write(xqspi, GQSPI_FIFO_CTRL_OFST,
311 			   GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK |
312 			   GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK |
313 			   GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK);
314 	/* Set by default to allow for high frequencies */
315 	zynqmp_gqspi_write(xqspi, GQSPI_LPBK_DLY_ADJ_OFST,
316 			   zynqmp_gqspi_read(xqspi, GQSPI_LPBK_DLY_ADJ_OFST) |
317 			   GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK);
318 	/* Reset thresholds */
319 	zynqmp_gqspi_write(xqspi, GQSPI_TX_THRESHOLD_OFST,
320 			   GQSPI_TX_FIFO_THRESHOLD_RESET_VAL);
321 	zynqmp_gqspi_write(xqspi, GQSPI_RX_THRESHOLD_OFST,
322 			   GQSPI_RX_FIFO_THRESHOLD);
323 	zynqmp_gqspi_write(xqspi, GQSPI_GF_THRESHOLD_OFST,
324 			   GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL);
325 	zynqmp_gqspi_selectslave(xqspi,
326 				 GQSPI_SELECT_FLASH_CS_LOWER,
327 				 GQSPI_SELECT_FLASH_BUS_LOWER);
328 	/* Initialize DMA */
329 	zynqmp_gqspi_write(xqspi,
330 			GQSPI_QSPIDMA_DST_CTRL_OFST,
331 			GQSPI_QSPIDMA_DST_CTRL_RESET_VAL);
332 
333 	/* Enable the GQSPI */
334 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
335 }
336 
337 /**
338  * zynqmp_qspi_copy_read_data:	Copy data to RX buffer
339  * @xqspi:	Pointer to the zynqmp_qspi structure
340  * @data:	The variable where data is stored
341  * @size:	Number of bytes to be copied from data to RX buffer
342  */
343 static void zynqmp_qspi_copy_read_data(struct zynqmp_qspi *xqspi,
344 				       ulong data, u8 size)
345 {
346 	memcpy(xqspi->rxbuf, &data, size);
347 	xqspi->rxbuf += size;
348 	xqspi->bytes_to_receive -= size;
349 }
350 
351 /**
352  * zynqmp_prepare_transfer_hardware:	Prepares hardware for transfer.
353  * @master:	Pointer to the spi_master structure which provides
354  *		information about the controller.
355  *
356  * This function enables SPI master controller.
357  *
358  * Return:	0 on success; error value otherwise
359  */
360 static int zynqmp_prepare_transfer_hardware(struct spi_master *master)
361 {
362 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
363 
364 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
365 	return 0;
366 }
367 
368 /**
369  * zynqmp_unprepare_transfer_hardware:	Relaxes hardware after transfer
370  * @master:	Pointer to the spi_master structure which provides
371  *		information about the controller.
372  *
373  * This function disables the SPI master controller.
374  *
375  * Return:	Always 0
376  */
377 static int zynqmp_unprepare_transfer_hardware(struct spi_master *master)
378 {
379 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
380 
381 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
382 	return 0;
383 }
384 
385 /**
386  * zynqmp_qspi_chipselect:	Select or deselect the chip select line
387  * @qspi:	Pointer to the spi_device structure
388  * @is_high:	Select(0) or deselect (1) the chip select line
389  */
390 static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high)
391 {
392 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
393 	ulong timeout;
394 	u32 genfifoentry = 0x0, statusreg;
395 
396 	genfifoentry |= GQSPI_GENFIFO_MODE_SPI;
397 	genfifoentry |= xqspi->genfifobus;
398 
399 	if (!is_high) {
400 		genfifoentry |= xqspi->genfifocs;
401 		genfifoentry |= GQSPI_GENFIFO_CS_SETUP;
402 	} else {
403 		genfifoentry |= GQSPI_GENFIFO_CS_HOLD;
404 	}
405 
406 	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
407 
408 	/* Dummy generic FIFO entry */
409 	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
410 
411 	/* Manually start the generic FIFO command */
412 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
413 			zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
414 			GQSPI_CFG_START_GEN_FIFO_MASK);
415 
416 	timeout = jiffies + msecs_to_jiffies(1000);
417 
418 	/* Wait until the generic FIFO command is empty */
419 	do {
420 		statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
421 
422 		if ((statusreg & GQSPI_ISR_GENFIFOEMPTY_MASK) &&
423 			(statusreg & GQSPI_ISR_TXEMPTY_MASK))
424 			break;
425 		else
426 			cpu_relax();
427 	} while (!time_after_eq(jiffies, timeout));
428 
429 	if (time_after_eq(jiffies, timeout))
430 		dev_err(xqspi->dev, "Chip select timed out\n");
431 }
432 
433 /**
434  * zynqmp_qspi_setup_transfer:	Configure QSPI controller for specified
435  *				transfer
436  * @qspi:	Pointer to the spi_device structure
437  * @transfer:	Pointer to the spi_transfer structure which provides
438  *		information about next transfer setup parameters
439  *
440  * Sets the operational mode of QSPI controller for the next QSPI transfer and
441  * sets the requested clock frequency.
442  *
443  * Return:	Always 0
444  *
445  * Note:
446  *	If the requested frequency is not an exact match with what can be
447  *	obtained using the pre-scalar value, the driver sets the clock
448  *	frequency which is lower than the requested frequency (maximum lower)
449  *	for the transfer.
450  *
451  *	If the requested frequency is higher or lower than that is supported
452  *	by the QSPI controller the driver will set the highest or lowest
453  *	frequency supported by controller.
454  */
455 static int zynqmp_qspi_setup_transfer(struct spi_device *qspi,
456 				      struct spi_transfer *transfer)
457 {
458 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
459 	ulong clk_rate;
460 	u32 config_reg, req_hz, baud_rate_val = 0;
461 
462 	if (transfer)
463 		req_hz = transfer->speed_hz;
464 	else
465 		req_hz = qspi->max_speed_hz;
466 
467 	/* Set the clock frequency */
468 	/* If req_hz == 0, default to lowest speed */
469 	clk_rate = clk_get_rate(xqspi->refclk);
470 
471 	while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
472 	       (clk_rate /
473 		(GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz)
474 		baud_rate_val++;
475 
476 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
477 
478 	/* Set the QSPI clock phase and clock polarity */
479 	config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
480 
481 	if (qspi->mode & SPI_CPHA)
482 		config_reg |= GQSPI_CFG_CLK_PHA_MASK;
483 	if (qspi->mode & SPI_CPOL)
484 		config_reg |= GQSPI_CFG_CLK_POL_MASK;
485 
486 	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
487 	config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
488 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
489 	return 0;
490 }
491 
492 /**
493  * zynqmp_qspi_setup:	Configure the QSPI controller
494  * @qspi:	Pointer to the spi_device structure
495  *
496  * Sets the operational mode of QSPI controller for the next QSPI transfer,
497  * baud rate and divisor value to setup the requested qspi clock.
498  *
499  * Return:	0 on success; error value otherwise.
500  */
501 static int zynqmp_qspi_setup(struct spi_device *qspi)
502 {
503 	if (qspi->master->busy)
504 		return -EBUSY;
505 	return 0;
506 }
507 
508 /**
509  * zynqmp_qspi_filltxfifo:	Fills the TX FIFO as long as there is room in
510  *				the FIFO or the bytes required to be
511  *				transmitted.
512  * @xqspi:	Pointer to the zynqmp_qspi structure
513  * @size:	Number of bytes to be copied from TX buffer to TX FIFO
514  */
515 static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
516 {
517 	u32 count = 0, intermediate;
518 
519 	while ((xqspi->bytes_to_transfer > 0) && (count < size)) {
520 		memcpy(&intermediate, xqspi->txbuf, 4);
521 		zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
522 
523 		if (xqspi->bytes_to_transfer >= 4) {
524 			xqspi->txbuf += 4;
525 			xqspi->bytes_to_transfer -= 4;
526 		} else {
527 			xqspi->txbuf += xqspi->bytes_to_transfer;
528 			xqspi->bytes_to_transfer = 0;
529 		}
530 		count++;
531 	}
532 }
533 
534 /**
535  * zynqmp_qspi_readrxfifo:	Fills the RX FIFO as long as there is room in
536  *				the FIFO.
537  * @xqspi:	Pointer to the zynqmp_qspi structure
538  * @size:	Number of bytes to be copied from RX buffer to RX FIFO
539  */
540 static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
541 {
542 	ulong data;
543 	int count = 0;
544 
545 	while ((count < size) && (xqspi->bytes_to_receive > 0)) {
546 		if (xqspi->bytes_to_receive >= 4) {
547 			(*(u32 *) xqspi->rxbuf) =
548 			zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
549 			xqspi->rxbuf += 4;
550 			xqspi->bytes_to_receive -= 4;
551 			count += 4;
552 		} else {
553 			data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
554 			count += xqspi->bytes_to_receive;
555 			zynqmp_qspi_copy_read_data(xqspi, data,
556 						   xqspi->bytes_to_receive);
557 			xqspi->bytes_to_receive = 0;
558 		}
559 	}
560 }
561 
562 /**
563  * zynqmp_process_dma_irq:	Handler for DMA done interrupt of QSPI
564  *				controller
565  * @xqspi:	zynqmp_qspi instance pointer
566  *
567  * This function handles DMA interrupt only.
568  */
569 static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
570 {
571 	u32 config_reg, genfifoentry;
572 
573 	dma_unmap_single(xqspi->dev, xqspi->dma_addr,
574 				xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
575 	xqspi->rxbuf += xqspi->dma_rx_bytes;
576 	xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
577 	xqspi->dma_rx_bytes = 0;
578 
579 	/* Disabling the DMA interrupts */
580 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST,
581 					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
582 
583 	if (xqspi->bytes_to_receive > 0) {
584 		/* Switch to IO mode,for remaining bytes to receive */
585 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
586 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
587 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
588 
589 		/* Initiate the transfer of remaining bytes */
590 		genfifoentry = xqspi->genfifoentry;
591 		genfifoentry |= xqspi->bytes_to_receive;
592 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
593 
594 		/* Dummy generic FIFO entry */
595 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
596 
597 		/* Manual start */
598 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
599 			(zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
600 			GQSPI_CFG_START_GEN_FIFO_MASK));
601 
602 		/* Enable the RX interrupts for IO mode */
603 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
604 				GQSPI_IER_GENFIFOEMPTY_MASK |
605 				GQSPI_IER_RXNEMPTY_MASK |
606 				GQSPI_IER_RXEMPTY_MASK);
607 	}
608 }
609 
610 /**
611  * zynqmp_qspi_irq:	Interrupt service routine of the QSPI controller
612  * @irq:	IRQ number
613  * @dev_id:	Pointer to the xqspi structure
614  *
615  * This function handles TX empty only.
616  * On TX empty interrupt this function reads the received data from RX FIFO
617  * and fills the TX FIFO if there is any data remaining to be transferred.
618  *
619  * Return:	IRQ_HANDLED when interrupt is handled
620  *		IRQ_NONE otherwise.
621  */
622 static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
623 {
624 	struct spi_master *master = dev_id;
625 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
626 	int ret = IRQ_NONE;
627 	u32 status, mask, dma_status = 0;
628 
629 	status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
630 	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status);
631 	mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST)));
632 
633 	/* Read and clear DMA status */
634 	if (xqspi->mode == GQSPI_MODE_DMA) {
635 		dma_status =
636 			zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST);
637 		zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
638 								dma_status);
639 	}
640 
641 	if (mask & GQSPI_ISR_TXNOT_FULL_MASK) {
642 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
643 		ret = IRQ_HANDLED;
644 	}
645 
646 	if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) {
647 		zynqmp_process_dma_irq(xqspi);
648 		ret = IRQ_HANDLED;
649 	} else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
650 			(mask & GQSPI_IER_GENFIFOEMPTY_MASK)) {
651 		zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
652 		ret = IRQ_HANDLED;
653 	}
654 
655 	if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0)
656 			&& ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
657 		zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK);
658 		spi_finalize_current_transfer(master);
659 		ret = IRQ_HANDLED;
660 	}
661 	return ret;
662 }
663 
664 /**
665  * zynqmp_qspi_selectspimode:	Selects SPI mode - x1 or x2 or x4.
666  * @xqspi:	xqspi is a pointer to the GQSPI instance
667  * @spimode:	spimode - SPI or DUAL or QUAD.
668  * Return:	Mask to set desired SPI mode in GENFIFO entry.
669  */
670 static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi,
671 						u8 spimode)
672 {
673 	u32 mask = 0;
674 
675 	switch (spimode) {
676 	case GQSPI_SELECT_MODE_DUALSPI:
677 		mask = GQSPI_GENFIFO_MODE_DUALSPI;
678 		break;
679 	case GQSPI_SELECT_MODE_QUADSPI:
680 		mask = GQSPI_GENFIFO_MODE_QUADSPI;
681 		break;
682 	case GQSPI_SELECT_MODE_SPI:
683 		mask = GQSPI_GENFIFO_MODE_SPI;
684 		break;
685 	default:
686 		dev_warn(xqspi->dev, "Invalid SPI mode\n");
687 	}
688 
689 	return mask;
690 }
691 
692 /**
693  * zynq_qspi_setuprxdma:	This function sets up the RX DMA operation
694  * @xqspi:	xqspi is a pointer to the GQSPI instance.
695  */
696 static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
697 {
698 	u32 rx_bytes, rx_rem, config_reg;
699 	dma_addr_t addr;
700 	u64 dma_align =  (u64)(uintptr_t)xqspi->rxbuf;
701 
702 	if ((xqspi->bytes_to_receive < 8) ||
703 		((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
704 		/* Setting to IO mode */
705 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
706 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
707 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
708 		xqspi->mode = GQSPI_MODE_IO;
709 		xqspi->dma_rx_bytes = 0;
710 		return;
711 	}
712 
713 	rx_rem = xqspi->bytes_to_receive % 4;
714 	rx_bytes = (xqspi->bytes_to_receive - rx_rem);
715 
716 	addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
717 						rx_bytes, DMA_FROM_DEVICE);
718 	if (dma_mapping_error(xqspi->dev, addr))
719 		dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
720 
721 	xqspi->dma_rx_bytes = rx_bytes;
722 	xqspi->dma_addr = addr;
723 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
724 				(u32)(addr & 0xffffffff));
725 	addr = ((addr >> 16) >> 16);
726 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
727 				((u32)addr) & 0xfff);
728 
729 	/* Enabling the DMA mode */
730 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
731 	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
732 	config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
733 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
734 
735 	/* Switch to DMA mode */
736 	xqspi->mode = GQSPI_MODE_DMA;
737 
738 	/* Write the number of bytes to transfer */
739 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
740 }
741 
742 /**
743  * zynqmp_qspi_txrxsetup:	This function checks the TX/RX buffers in
744  *				the transfer and sets up the GENFIFO entries,
745  *				TX FIFO as required.
746  * @xqspi:	xqspi is a pointer to the GQSPI instance.
747  * @transfer:	It is a pointer to the structure containing transfer data.
748  * @genfifoentry:	genfifoentry is pointer to the variable in which
749  *			GENFIFO	mask is returned to calling function
750  */
751 static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi,
752 				  struct spi_transfer *transfer,
753 				  u32 *genfifoentry)
754 {
755 	u32 config_reg;
756 
757 	/* Transmit */
758 	if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) {
759 		/* Setup data to be TXed */
760 		*genfifoentry &= ~GQSPI_GENFIFO_RX;
761 		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
762 		*genfifoentry |= GQSPI_GENFIFO_TX;
763 		*genfifoentry |=
764 			zynqmp_qspi_selectspimode(xqspi, transfer->tx_nbits);
765 		xqspi->bytes_to_transfer = transfer->len;
766 		if (xqspi->mode == GQSPI_MODE_DMA) {
767 			config_reg = zynqmp_gqspi_read(xqspi,
768 							GQSPI_CONFIG_OFST);
769 			config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
770 			zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
771 								config_reg);
772 			xqspi->mode = GQSPI_MODE_IO;
773 		}
774 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
775 		/* Discard RX data */
776 		xqspi->bytes_to_receive = 0;
777 	} else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) {
778 		/* Receive */
779 
780 		/* TX auto fill */
781 		*genfifoentry &= ~GQSPI_GENFIFO_TX;
782 		/* Setup RX */
783 		*genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
784 		*genfifoentry |= GQSPI_GENFIFO_RX;
785 		*genfifoentry |=
786 			zynqmp_qspi_selectspimode(xqspi, transfer->rx_nbits);
787 		xqspi->bytes_to_transfer = 0;
788 		xqspi->bytes_to_receive = transfer->len;
789 		zynq_qspi_setuprxdma(xqspi);
790 	}
791 }
792 
793 /**
794  * zynqmp_qspi_start_transfer:	Initiates the QSPI transfer
795  * @master:	Pointer to the spi_master structure which provides
796  *		information about the controller.
797  * @qspi:	Pointer to the spi_device structure
798  * @transfer:	Pointer to the spi_transfer structure which provide information
799  *		about next transfer parameters
800  *
801  * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
802  * transfer to be completed.
803  *
804  * Return:	Number of bytes transferred in the last transfer
805  */
806 static int zynqmp_qspi_start_transfer(struct spi_master *master,
807 				      struct spi_device *qspi,
808 				      struct spi_transfer *transfer)
809 {
810 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
811 	u32 genfifoentry = 0x0, transfer_len;
812 
813 	xqspi->txbuf = transfer->tx_buf;
814 	xqspi->rxbuf = transfer->rx_buf;
815 
816 	zynqmp_qspi_setup_transfer(qspi, transfer);
817 
818 	genfifoentry |= xqspi->genfifocs;
819 	genfifoentry |= xqspi->genfifobus;
820 
821 	zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry);
822 
823 	if (xqspi->mode == GQSPI_MODE_DMA)
824 		transfer_len = xqspi->dma_rx_bytes;
825 	else
826 		transfer_len = transfer->len;
827 
828 	xqspi->genfifoentry = genfifoentry;
829 	if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {
830 		genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
831 		genfifoentry |= transfer_len;
832 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
833 	} else {
834 		int tempcount = transfer_len;
835 		u32 exponent = 8;	/* 2^8 = 256 */
836 		u8 imm_data = tempcount & 0xFF;
837 
838 		tempcount &= ~(tempcount & 0xFF);
839 		/* Immediate entry */
840 		if (tempcount != 0) {
841 			/* Exponent entries */
842 			genfifoentry |= GQSPI_GENFIFO_EXP;
843 			while (tempcount != 0) {
844 				if (tempcount & GQSPI_GENFIFO_EXP_START) {
845 					genfifoentry &=
846 					    ~GQSPI_GENFIFO_IMM_DATA_MASK;
847 					genfifoentry |= exponent;
848 					zynqmp_gqspi_write(xqspi,
849 							   GQSPI_GEN_FIFO_OFST,
850 							   genfifoentry);
851 				}
852 				tempcount = tempcount >> 1;
853 				exponent++;
854 			}
855 		}
856 		if (imm_data != 0) {
857 			genfifoentry &= ~GQSPI_GENFIFO_EXP;
858 			genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
859 			genfifoentry |= (u8) (imm_data & 0xFF);
860 			zynqmp_gqspi_write(xqspi,
861 					   GQSPI_GEN_FIFO_OFST, genfifoentry);
862 		}
863 	}
864 
865 	if ((xqspi->mode == GQSPI_MODE_IO) &&
866 			(xqspi->rxbuf != NULL)) {
867 		/* Dummy generic FIFO entry */
868 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
869 	}
870 
871 	/* Since we are using manual mode */
872 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
873 			   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
874 			   GQSPI_CFG_START_GEN_FIFO_MASK);
875 
876 	if (xqspi->txbuf != NULL)
877 		/* Enable interrupts for TX */
878 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
879 				   GQSPI_IER_TXEMPTY_MASK |
880 					GQSPI_IER_GENFIFOEMPTY_MASK |
881 					GQSPI_IER_TXNOT_FULL_MASK);
882 
883 	if (xqspi->rxbuf != NULL) {
884 		/* Enable interrupts for RX */
885 		if (xqspi->mode == GQSPI_MODE_DMA) {
886 			/* Enable DMA interrupts */
887 			zynqmp_gqspi_write(xqspi,
888 					GQSPI_QSPIDMA_DST_I_EN_OFST,
889 					GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
890 		} else {
891 			zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
892 					GQSPI_IER_GENFIFOEMPTY_MASK |
893 					GQSPI_IER_RXNEMPTY_MASK |
894 					GQSPI_IER_RXEMPTY_MASK);
895 		}
896 	}
897 
898 	return transfer->len;
899 }
900 
901 /**
902  * zynqmp_qspi_suspend:	Suspend method for the QSPI driver
903  * @_dev:	Address of the platform_device structure
904  *
905  * This function stops the QSPI driver queue and disables the QSPI controller
906  *
907  * Return:	Always 0
908  */
909 static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
910 {
911 	struct spi_master *master = dev_get_drvdata(dev);
912 
913 	spi_master_suspend(master);
914 
915 	zynqmp_unprepare_transfer_hardware(master);
916 
917 	return 0;
918 }
919 
920 /**
921  * zynqmp_qspi_resume:	Resume method for the QSPI driver
922  * @dev:	Address of the platform_device structure
923  *
924  * The function starts the QSPI driver queue and initializes the QSPI
925  * controller
926  *
927  * Return:	0 on success; error value otherwise
928  */
929 static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
930 {
931 	struct spi_master *master = dev_get_drvdata(dev);
932 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
933 	int ret = 0;
934 
935 	ret = clk_enable(xqspi->pclk);
936 	if (ret) {
937 		dev_err(dev, "Cannot enable APB clock.\n");
938 		return ret;
939 	}
940 
941 	ret = clk_enable(xqspi->refclk);
942 	if (ret) {
943 		dev_err(dev, "Cannot enable device clock.\n");
944 		clk_disable(xqspi->pclk);
945 		return ret;
946 	}
947 
948 	spi_master_resume(master);
949 
950 	clk_disable(xqspi->refclk);
951 	clk_disable(xqspi->pclk);
952 	return 0;
953 }
954 
955 /**
956  * zynqmp_runtime_suspend - Runtime suspend method for the SPI driver
957  * @dev:	Address of the platform_device structure
958  *
959  * This function disables the clocks
960  *
961  * Return:	Always 0
962  */
963 static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
964 {
965 	struct spi_master *master = dev_get_drvdata(dev);
966 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
967 
968 	clk_disable(xqspi->refclk);
969 	clk_disable(xqspi->pclk);
970 
971 	return 0;
972 }
973 
974 /**
975  * zynqmp_runtime_resume - Runtime resume method for the SPI driver
976  * @dev:	Address of the platform_device structure
977  *
978  * This function enables the clocks
979  *
980  * Return:	0 on success and error value on error
981  */
982 static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
983 {
984 	struct spi_master *master = dev_get_drvdata(dev);
985 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
986 	int ret;
987 
988 	ret = clk_enable(xqspi->pclk);
989 	if (ret) {
990 		dev_err(dev, "Cannot enable APB clock.\n");
991 		return ret;
992 	}
993 
994 	ret = clk_enable(xqspi->refclk);
995 	if (ret) {
996 		dev_err(dev, "Cannot enable device clock.\n");
997 		clk_disable(xqspi->pclk);
998 		return ret;
999 	}
1000 
1001 	return 0;
1002 }
1003 
1004 static const struct dev_pm_ops zynqmp_qspi_dev_pm_ops = {
1005 	SET_RUNTIME_PM_OPS(zynqmp_runtime_suspend,
1006 			   zynqmp_runtime_resume, NULL)
1007 	SET_SYSTEM_SLEEP_PM_OPS(zynqmp_qspi_suspend, zynqmp_qspi_resume)
1008 };
1009 
1010 /**
1011  * zynqmp_qspi_probe:	Probe method for the QSPI driver
1012  * @pdev:	Pointer to the platform_device structure
1013  *
1014  * This function initializes the driver data structures and the hardware.
1015  *
1016  * Return:	0 on success; error value otherwise
1017  */
1018 static int zynqmp_qspi_probe(struct platform_device *pdev)
1019 {
1020 	int ret = 0;
1021 	struct spi_master *master;
1022 	struct zynqmp_qspi *xqspi;
1023 	struct resource *res;
1024 	struct device *dev = &pdev->dev;
1025 
1026 	eemi_ops = zynqmp_pm_get_eemi_ops();
1027 	if (IS_ERR(eemi_ops))
1028 		return PTR_ERR(eemi_ops);
1029 
1030 	master = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
1031 	if (!master)
1032 		return -ENOMEM;
1033 
1034 	xqspi = spi_master_get_devdata(master);
1035 	master->dev.of_node = pdev->dev.of_node;
1036 	platform_set_drvdata(pdev, master);
1037 
1038 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1039 	xqspi->regs = devm_ioremap_resource(&pdev->dev, res);
1040 	if (IS_ERR(xqspi->regs)) {
1041 		ret = PTR_ERR(xqspi->regs);
1042 		goto remove_master;
1043 	}
1044 
1045 	xqspi->dev = dev;
1046 	xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
1047 	if (IS_ERR(xqspi->pclk)) {
1048 		dev_err(dev, "pclk clock not found.\n");
1049 		ret = PTR_ERR(xqspi->pclk);
1050 		goto remove_master;
1051 	}
1052 
1053 	ret = clk_prepare_enable(xqspi->pclk);
1054 	if (ret) {
1055 		dev_err(dev, "Unable to enable APB clock.\n");
1056 		goto remove_master;
1057 	}
1058 
1059 	xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
1060 	if (IS_ERR(xqspi->refclk)) {
1061 		dev_err(dev, "ref_clk clock not found.\n");
1062 		ret = PTR_ERR(xqspi->refclk);
1063 		goto clk_dis_pclk;
1064 	}
1065 
1066 	ret = clk_prepare_enable(xqspi->refclk);
1067 	if (ret) {
1068 		dev_err(dev, "Unable to enable device clock.\n");
1069 		goto clk_dis_pclk;
1070 	}
1071 
1072 	pm_runtime_use_autosuspend(&pdev->dev);
1073 	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1074 	pm_runtime_set_active(&pdev->dev);
1075 	pm_runtime_enable(&pdev->dev);
1076 	/* QSPI controller initializations */
1077 	zynqmp_qspi_init_hw(xqspi);
1078 
1079 	pm_runtime_mark_last_busy(&pdev->dev);
1080 	pm_runtime_put_autosuspend(&pdev->dev);
1081 	xqspi->irq = platform_get_irq(pdev, 0);
1082 	if (xqspi->irq <= 0) {
1083 		ret = -ENXIO;
1084 		dev_err(dev, "irq resource not found\n");
1085 		goto clk_dis_all;
1086 	}
1087 	ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
1088 			       0, pdev->name, master);
1089 	if (ret != 0) {
1090 		ret = -ENXIO;
1091 		dev_err(dev, "request_irq failed\n");
1092 		goto clk_dis_all;
1093 	}
1094 
1095 	master->num_chipselect = GQSPI_DEFAULT_NUM_CS;
1096 
1097 	master->setup = zynqmp_qspi_setup;
1098 	master->set_cs = zynqmp_qspi_chipselect;
1099 	master->transfer_one = zynqmp_qspi_start_transfer;
1100 	master->prepare_transfer_hardware = zynqmp_prepare_transfer_hardware;
1101 	master->unprepare_transfer_hardware =
1102 					zynqmp_unprepare_transfer_hardware;
1103 	master->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
1104 	master->bits_per_word_mask = SPI_BPW_MASK(8);
1105 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
1106 			    SPI_TX_DUAL | SPI_TX_QUAD;
1107 
1108 	if (master->dev.parent == NULL)
1109 		master->dev.parent = &master->dev;
1110 
1111 	ret = spi_register_master(master);
1112 	if (ret)
1113 		goto clk_dis_all;
1114 
1115 	return 0;
1116 
1117 clk_dis_all:
1118 	pm_runtime_set_suspended(&pdev->dev);
1119 	pm_runtime_disable(&pdev->dev);
1120 	clk_disable_unprepare(xqspi->refclk);
1121 clk_dis_pclk:
1122 	clk_disable_unprepare(xqspi->pclk);
1123 remove_master:
1124 	spi_master_put(master);
1125 
1126 	return ret;
1127 }
1128 
1129 /**
1130  * zynqmp_qspi_remove:	Remove method for the QSPI driver
1131  * @pdev:	Pointer to the platform_device structure
1132  *
1133  * This function is called if a device is physically removed from the system or
1134  * if the driver module is being unloaded. It frees all resources allocated to
1135  * the device.
1136  *
1137  * Return:	0 Always
1138  */
1139 static int zynqmp_qspi_remove(struct platform_device *pdev)
1140 {
1141 	struct spi_master *master = platform_get_drvdata(pdev);
1142 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
1143 
1144 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
1145 	clk_disable_unprepare(xqspi->refclk);
1146 	clk_disable_unprepare(xqspi->pclk);
1147 	pm_runtime_set_suspended(&pdev->dev);
1148 	pm_runtime_disable(&pdev->dev);
1149 
1150 	spi_unregister_master(master);
1151 
1152 	return 0;
1153 }
1154 
1155 static const struct of_device_id zynqmp_qspi_of_match[] = {
1156 	{ .compatible = "xlnx,zynqmp-qspi-1.0", },
1157 	{ /* End of table */ }
1158 };
1159 
1160 MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
1161 
1162 static struct platform_driver zynqmp_qspi_driver = {
1163 	.probe = zynqmp_qspi_probe,
1164 	.remove = zynqmp_qspi_remove,
1165 	.driver = {
1166 		.name = "zynqmp-qspi",
1167 		.of_match_table = zynqmp_qspi_of_match,
1168 		.pm = &zynqmp_qspi_dev_pm_ops,
1169 	},
1170 };
1171 
1172 module_platform_driver(zynqmp_qspi_driver);
1173 
1174 MODULE_AUTHOR("Xilinx, Inc.");
1175 MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
1176 MODULE_LICENSE("GPL");
1177