1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2013 Xilinx, Inc.
4  * (C) Copyright 2015 Jagan Teki <jteki@openedev.com>
5  *
6  * Xilinx Zynq Quad-SPI(QSPI) controller driver (master mode only)
7  */
8 
9 #include <clk.h>
10 #include <common.h>
11 #include <dm.h>
12 #include <dm/device_compat.h>
13 #include <log.h>
14 #include <malloc.h>
15 #include <spi.h>
16 #include <asm/global_data.h>
17 #include <asm/io.h>
18 #include <linux/bitops.h>
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 /* zynq qspi register bit masks ZYNQ_QSPI_<REG>_<BIT>_MASK */
23 #define ZYNQ_QSPI_CR_IFMODE_MASK	BIT(31)	/* Flash intrface mode*/
24 #define ZYNQ_QSPI_CR_MSA_MASK		BIT(15)	/* Manual start enb */
25 #define ZYNQ_QSPI_CR_MCS_MASK		BIT(14)	/* Manual chip select */
26 #define ZYNQ_QSPI_CR_PCS_MASK		BIT(10)	/* Peri chip select */
27 #define ZYNQ_QSPI_CR_FW_MASK		GENMASK(7, 6)	/* FIFO width */
28 #define ZYNQ_QSPI_CR_SS_MASK		GENMASK(13, 10)	/* Slave Select */
29 #define ZYNQ_QSPI_CR_BAUD_MASK		GENMASK(5, 3)	/* Baud rate div */
30 #define ZYNQ_QSPI_CR_CPHA_MASK		BIT(2)	/* Clock phase */
31 #define ZYNQ_QSPI_CR_CPOL_MASK		BIT(1)	/* Clock polarity */
32 #define ZYNQ_QSPI_CR_MSTREN_MASK	BIT(0)	/* Mode select */
33 #define ZYNQ_QSPI_IXR_RXNEMPTY_MASK	BIT(4)	/* RX_FIFO_not_empty */
34 #define ZYNQ_QSPI_IXR_TXOW_MASK		BIT(2)	/* TX_FIFO_not_full */
35 #define ZYNQ_QSPI_IXR_ALL_MASK		GENMASK(6, 0)	/* All IXR bits */
36 #define ZYNQ_QSPI_ENR_SPI_EN_MASK	BIT(0)	/* SPI Enable */
37 #define ZYNQ_QSPI_LQSPICFG_LQMODE_MASK	BIT(31) /* Linear QSPI Mode */
38 
39 /* zynq qspi Transmit Data Register */
40 #define ZYNQ_QSPI_TXD_00_00_OFFSET	0x1C	/* Transmit 4-byte inst */
41 #define ZYNQ_QSPI_TXD_00_01_OFFSET	0x80	/* Transmit 1-byte inst */
42 #define ZYNQ_QSPI_TXD_00_10_OFFSET	0x84	/* Transmit 2-byte inst */
43 #define ZYNQ_QSPI_TXD_00_11_OFFSET	0x88	/* Transmit 3-byte inst */
44 
45 #define ZYNQ_QSPI_TXFIFO_THRESHOLD	1	/* Tx FIFO threshold level*/
46 #define ZYNQ_QSPI_RXFIFO_THRESHOLD	32	/* Rx FIFO threshold level */
47 
48 #define ZYNQ_QSPI_CR_BAUD_MAX		8	/* Baud rate divisor max val */
49 #define ZYNQ_QSPI_CR_BAUD_SHIFT		3	/* Baud rate divisor shift */
50 #define ZYNQ_QSPI_CR_SS_SHIFT		10	/* Slave select shift */
51 
52 #define ZYNQ_QSPI_FIFO_DEPTH		63
53 #define ZYNQ_QSPI_WAIT			(CONFIG_SYS_HZ / 100)	/* 10 ms */
54 
55 /* zynq qspi register set */
56 struct zynq_qspi_regs {
57 	u32 cr;		/* 0x00 */
58 	u32 isr;	/* 0x04 */
59 	u32 ier;	/* 0x08 */
60 	u32 idr;	/* 0x0C */
61 	u32 imr;	/* 0x10 */
62 	u32 enr;	/* 0x14 */
63 	u32 dr;		/* 0x18 */
64 	u32 txd0r;	/* 0x1C */
65 	u32 drxr;	/* 0x20 */
66 	u32 sicr;	/* 0x24 */
67 	u32 txftr;	/* 0x28 */
68 	u32 rxftr;	/* 0x2C */
69 	u32 gpior;	/* 0x30 */
70 	u32 reserved0[19];
71 	u32 txd1r;	/* 0x80 */
72 	u32 txd2r;	/* 0x84 */
73 	u32 txd3r;	/* 0x88 */
74 	u32 reserved1[5];
75 	u32 lqspicfg;	/* 0xA0 */
76 	u32 lqspists;	/* 0xA4 */
77 };
78 
79 /* zynq qspi platform data */
80 struct zynq_qspi_plat {
81 	struct zynq_qspi_regs *regs;
82 	u32 frequency;          /* input frequency */
83 	u32 speed_hz;
84 };
85 
86 /* zynq qspi priv */
87 struct zynq_qspi_priv {
88 	struct zynq_qspi_regs *regs;
89 	u8 cs;
90 	u8 mode;
91 	u8 fifo_depth;
92 	u32 freq;		/* required frequency */
93 	const void *tx_buf;
94 	void *rx_buf;
95 	unsigned len;
96 	int bytes_to_transfer;
97 	int bytes_to_receive;
98 	unsigned int is_inst;
99 	unsigned cs_change:1;
100 };
101 
zynq_qspi_of_to_plat(struct udevice * bus)102 static int zynq_qspi_of_to_plat(struct udevice *bus)
103 {
104 	struct zynq_qspi_plat *plat = dev_get_plat(bus);
105 	const void *blob = gd->fdt_blob;
106 	int node = dev_of_offset(bus);
107 
108 	plat->regs = (struct zynq_qspi_regs *)fdtdec_get_addr(blob,
109 							      node, "reg");
110 
111 	return 0;
112 }
113 
114 /**
115  * zynq_qspi_init_hw - Initialize the hardware
116  * @priv:	Pointer to the zynq_qspi_priv structure
117  *
118  * The default settings of the QSPI controller's configurable parameters on
119  * reset are
120  *	- Master mode
121  *	- Baud rate divisor is set to 2
122  *	- Threshold value for TX FIFO not full interrupt is set to 1
123  *	- Flash memory interface mode enabled
124  *	- Size of the word to be transferred as 8 bit
125  * This function performs the following actions
126  *	- Disable and clear all the interrupts
127  *	- Enable manual slave select
128  *	- Enable auto start
129  *	- Deselect all the chip select lines
130  *	- Set the size of the word to be transferred as 32 bit
131  *	- Set the little endian mode of TX FIFO and
132  *	- Enable the QSPI controller
133  */
zynq_qspi_init_hw(struct zynq_qspi_priv * priv)134 static void zynq_qspi_init_hw(struct zynq_qspi_priv *priv)
135 {
136 	struct zynq_qspi_regs *regs = priv->regs;
137 	u32 confr;
138 
139 	/* Disable QSPI */
140 	writel(~ZYNQ_QSPI_ENR_SPI_EN_MASK, &regs->enr);
141 
142 	/* Disable Interrupts */
143 	writel(ZYNQ_QSPI_IXR_ALL_MASK, &regs->idr);
144 
145 	/* Clear the TX and RX threshold reg */
146 	writel(ZYNQ_QSPI_TXFIFO_THRESHOLD, &regs->txftr);
147 	writel(ZYNQ_QSPI_RXFIFO_THRESHOLD, &regs->rxftr);
148 
149 	/* Clear the RX FIFO */
150 	while (readl(&regs->isr) & ZYNQ_QSPI_IXR_RXNEMPTY_MASK)
151 		readl(&regs->drxr);
152 
153 	/* Clear Interrupts */
154 	writel(ZYNQ_QSPI_IXR_ALL_MASK, &regs->isr);
155 
156 	/* Manual slave select and Auto start */
157 	confr = readl(&regs->cr);
158 	confr &= ~ZYNQ_QSPI_CR_MSA_MASK;
159 	confr |= ZYNQ_QSPI_CR_IFMODE_MASK | ZYNQ_QSPI_CR_MCS_MASK |
160 		ZYNQ_QSPI_CR_PCS_MASK | ZYNQ_QSPI_CR_FW_MASK |
161 		ZYNQ_QSPI_CR_MSTREN_MASK;
162 	writel(confr, &regs->cr);
163 
164 	/* Disable the LQSPI feature */
165 	confr = readl(&regs->lqspicfg);
166 	confr &= ~ZYNQ_QSPI_LQSPICFG_LQMODE_MASK;
167 	writel(confr, &regs->lqspicfg);
168 
169 	/* Enable SPI */
170 	writel(ZYNQ_QSPI_ENR_SPI_EN_MASK, &regs->enr);
171 }
172 
zynq_qspi_probe(struct udevice * bus)173 static int zynq_qspi_probe(struct udevice *bus)
174 {
175 	struct zynq_qspi_plat *plat = dev_get_plat(bus);
176 	struct zynq_qspi_priv *priv = dev_get_priv(bus);
177 	struct clk clk;
178 	unsigned long clock;
179 	int ret;
180 
181 	priv->regs = plat->regs;
182 	priv->fifo_depth = ZYNQ_QSPI_FIFO_DEPTH;
183 
184 	ret = clk_get_by_name(bus, "ref_clk", &clk);
185 	if (ret < 0) {
186 		dev_err(bus, "failed to get clock\n");
187 		return ret;
188 	}
189 
190 	clock = clk_get_rate(&clk);
191 	if (IS_ERR_VALUE(clock)) {
192 		dev_err(bus, "failed to get rate\n");
193 		return clock;
194 	}
195 
196 	ret = clk_enable(&clk);
197 	if (ret) {
198 		dev_err(bus, "failed to enable clock\n");
199 		return ret;
200 	}
201 
202 	/* init the zynq spi hw */
203 	zynq_qspi_init_hw(priv);
204 
205 	plat->frequency = clock;
206 	plat->speed_hz = plat->frequency / 2;
207 
208 	debug("%s: max-frequency=%d\n", __func__, plat->speed_hz);
209 
210 	return 0;
211 }
212 
213 /**
214  * zynq_qspi_read_data - Copy data to RX buffer
215  * @priv:	Pointer to the zynq_qspi_priv structure
216  * @data:	The 32 bit variable where data is stored
217  * @size:	Number of bytes to be copied from data to RX buffer
218  */
zynq_qspi_read_data(struct zynq_qspi_priv * priv,u32 data,u8 size)219 static void zynq_qspi_read_data(struct zynq_qspi_priv *priv, u32 data, u8 size)
220 {
221 	u8 byte3;
222 
223 	debug("%s: data 0x%04x rx_buf addr: 0x%08x size %d\n", __func__ ,
224 	      data, (unsigned)(priv->rx_buf), size);
225 
226 	if (priv->rx_buf) {
227 		switch (size) {
228 		case 1:
229 			*((u8 *)priv->rx_buf) = data;
230 			priv->rx_buf += 1;
231 			break;
232 		case 2:
233 			*((u16 *)priv->rx_buf) = data;
234 			priv->rx_buf += 2;
235 			break;
236 		case 3:
237 			*((u16 *)priv->rx_buf) = data;
238 			priv->rx_buf += 2;
239 			byte3 = (u8)(data >> 16);
240 			*((u8 *)priv->rx_buf) = byte3;
241 			priv->rx_buf += 1;
242 			break;
243 		case 4:
244 			/* Can not assume word aligned buffer */
245 			memcpy(priv->rx_buf, &data, size);
246 			priv->rx_buf += 4;
247 			break;
248 		default:
249 			/* This will never execute */
250 			break;
251 		}
252 	}
253 	priv->bytes_to_receive -= size;
254 	if (priv->bytes_to_receive < 0)
255 		priv->bytes_to_receive = 0;
256 }
257 
258 /**
259  * zynq_qspi_write_data - Copy data from TX buffer
260  * @priv:	Pointer to the zynq_qspi_priv structure
261  * @data:	Pointer to the 32 bit variable where data is to be copied
262  * @size:	Number of bytes to be copied from TX buffer to data
263  */
zynq_qspi_write_data(struct zynq_qspi_priv * priv,u32 * data,u8 size)264 static void zynq_qspi_write_data(struct  zynq_qspi_priv *priv,
265 		u32 *data, u8 size)
266 {
267 	if (priv->tx_buf) {
268 		switch (size) {
269 		case 1:
270 			*data = *((u8 *)priv->tx_buf);
271 			priv->tx_buf += 1;
272 			*data |= 0xFFFFFF00;
273 			break;
274 		case 2:
275 			*data = *((u16 *)priv->tx_buf);
276 			priv->tx_buf += 2;
277 			*data |= 0xFFFF0000;
278 			break;
279 		case 3:
280 			*data = *((u16 *)priv->tx_buf);
281 			priv->tx_buf += 2;
282 			*data |= (*((u8 *)priv->tx_buf) << 16);
283 			priv->tx_buf += 1;
284 			*data |= 0xFF000000;
285 			break;
286 		case 4:
287 			/* Can not assume word aligned buffer */
288 			memcpy(data, priv->tx_buf, size);
289 			priv->tx_buf += 4;
290 			break;
291 		default:
292 			/* This will never execute */
293 			break;
294 		}
295 	} else {
296 		*data = 0;
297 	}
298 
299 	debug("%s: data 0x%08x tx_buf addr: 0x%08x size %d\n", __func__,
300 	      *data, (u32)priv->tx_buf, size);
301 
302 	priv->bytes_to_transfer -= size;
303 	if (priv->bytes_to_transfer < 0)
304 		priv->bytes_to_transfer = 0;
305 }
306 
307 /**
308  * zynq_qspi_chipselect - Select or deselect the chip select line
309  * @priv:	Pointer to the zynq_qspi_priv structure
310  * @is_on:	Select(1) or deselect (0) the chip select line
311  */
zynq_qspi_chipselect(struct zynq_qspi_priv * priv,int is_on)312 static void zynq_qspi_chipselect(struct  zynq_qspi_priv *priv, int is_on)
313 {
314 	u32 confr;
315 	struct zynq_qspi_regs *regs = priv->regs;
316 
317 	confr = readl(&regs->cr);
318 
319 	if (is_on) {
320 		/* Select the slave */
321 		confr &= ~ZYNQ_QSPI_CR_SS_MASK;
322 		confr |= (~(1 << priv->cs) << ZYNQ_QSPI_CR_SS_SHIFT) &
323 					ZYNQ_QSPI_CR_SS_MASK;
324 	} else
325 		/* Deselect the slave */
326 		confr |= ZYNQ_QSPI_CR_SS_MASK;
327 
328 	writel(confr, &regs->cr);
329 }
330 
331 /**
332  * zynq_qspi_fill_tx_fifo - Fills the TX FIFO with as many bytes as possible
333  * @priv:	Pointer to the zynq_qspi_priv structure
334  * @size:	Number of bytes to be copied to fifo
335  */
zynq_qspi_fill_tx_fifo(struct zynq_qspi_priv * priv,u32 size)336 static void zynq_qspi_fill_tx_fifo(struct zynq_qspi_priv *priv, u32 size)
337 {
338 	u32 data = 0;
339 	u32 fifocount = 0;
340 	unsigned len, offset;
341 	struct zynq_qspi_regs *regs = priv->regs;
342 	static const unsigned offsets[4] = {
343 		ZYNQ_QSPI_TXD_00_00_OFFSET, ZYNQ_QSPI_TXD_00_01_OFFSET,
344 		ZYNQ_QSPI_TXD_00_10_OFFSET, ZYNQ_QSPI_TXD_00_11_OFFSET };
345 
346 	while ((fifocount < size) &&
347 			(priv->bytes_to_transfer > 0)) {
348 		if (priv->bytes_to_transfer >= 4) {
349 			if (priv->tx_buf) {
350 				memcpy(&data, priv->tx_buf, 4);
351 				priv->tx_buf += 4;
352 			} else {
353 				data = 0;
354 			}
355 			writel(data, &regs->txd0r);
356 			priv->bytes_to_transfer -= 4;
357 			fifocount++;
358 		} else {
359 			/* Write TXD1, TXD2, TXD3 only if TxFIFO is empty. */
360 			if (!(readl(&regs->isr)
361 					& ZYNQ_QSPI_IXR_TXOW_MASK) &&
362 					!priv->rx_buf)
363 				return;
364 			len = priv->bytes_to_transfer;
365 			zynq_qspi_write_data(priv, &data, len);
366 			offset = (priv->rx_buf) ? offsets[0] : offsets[len];
367 			writel(data, &regs->cr + (offset / 4));
368 		}
369 	}
370 }
371 
372 /**
373  * zynq_qspi_irq_poll - Interrupt service routine of the QSPI controller
374  * @priv:	Pointer to the zynq_qspi structure
375  *
376  * This function handles TX empty and Mode Fault interrupts only.
377  * On TX empty interrupt this function reads the received data from RX FIFO and
378  * fills the TX FIFO if there is any data remaining to be transferred.
379  * On Mode Fault interrupt this function indicates that transfer is completed,
380  * the SPI subsystem will identify the error as the remaining bytes to be
381  * transferred is non-zero.
382  *
383  * returns:	0 for poll timeout
384  *		1 transfer operation complete
385  */
zynq_qspi_irq_poll(struct zynq_qspi_priv * priv)386 static int zynq_qspi_irq_poll(struct zynq_qspi_priv *priv)
387 {
388 	struct zynq_qspi_regs *regs = priv->regs;
389 	u32 rxindex = 0;
390 	u32 rxcount;
391 	u32 status, timeout;
392 
393 	/* Poll until any of the interrupt status bits are set */
394 	timeout = get_timer(0);
395 	do {
396 		status = readl(&regs->isr);
397 	} while ((status == 0) &&
398 		(get_timer(timeout) < ZYNQ_QSPI_WAIT));
399 
400 	if (status == 0) {
401 		printf("zynq_qspi_irq_poll: Timeout!\n");
402 		return -ETIMEDOUT;
403 	}
404 
405 	writel(status, &regs->isr);
406 
407 	/* Disable all interrupts */
408 	writel(ZYNQ_QSPI_IXR_ALL_MASK, &regs->idr);
409 	if ((status & ZYNQ_QSPI_IXR_TXOW_MASK) ||
410 	    (status & ZYNQ_QSPI_IXR_RXNEMPTY_MASK)) {
411 		/*
412 		 * This bit is set when Tx FIFO has < THRESHOLD entries. We have
413 		 * the THRESHOLD value set to 1, so this bit indicates Tx FIFO
414 		 * is empty
415 		 */
416 		rxcount = priv->bytes_to_receive - priv->bytes_to_transfer;
417 		rxcount = (rxcount % 4) ? ((rxcount/4)+1) : (rxcount/4);
418 		while ((rxindex < rxcount) &&
419 				(rxindex < ZYNQ_QSPI_RXFIFO_THRESHOLD)) {
420 			/* Read out the data from the RX FIFO */
421 			u32 data;
422 			data = readl(&regs->drxr);
423 
424 			if (priv->bytes_to_receive >= 4) {
425 				if (priv->rx_buf) {
426 					memcpy(priv->rx_buf, &data, 4);
427 					priv->rx_buf += 4;
428 				}
429 				priv->bytes_to_receive -= 4;
430 			} else {
431 				zynq_qspi_read_data(priv, data,
432 						    priv->bytes_to_receive);
433 			}
434 			rxindex++;
435 		}
436 
437 		if (priv->bytes_to_transfer) {
438 			/* There is more data to send */
439 			zynq_qspi_fill_tx_fifo(priv,
440 					       ZYNQ_QSPI_RXFIFO_THRESHOLD);
441 
442 			writel(ZYNQ_QSPI_IXR_ALL_MASK, &regs->ier);
443 		} else {
444 			/*
445 			 * If transfer and receive is completed then only send
446 			 * complete signal
447 			 */
448 			if (!priv->bytes_to_receive) {
449 				/* return operation complete */
450 				writel(ZYNQ_QSPI_IXR_ALL_MASK,
451 				       &regs->idr);
452 				return 1;
453 			}
454 		}
455 	}
456 
457 	return 0;
458 }
459 
460 /**
461  * zynq_qspi_start_transfer - Initiates the QSPI transfer
462  * @priv:	Pointer to the zynq_qspi_priv structure
463  *
464  * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
465  * transfer to be completed.
466  *
467  * returns:	Number of bytes transferred in the last transfer
468  */
zynq_qspi_start_transfer(struct zynq_qspi_priv * priv)469 static int zynq_qspi_start_transfer(struct zynq_qspi_priv *priv)
470 {
471 	u32 data = 0;
472 	struct zynq_qspi_regs *regs = priv->regs;
473 
474 	debug("%s: qspi: 0x%08x transfer: 0x%08x len: %d\n", __func__,
475 	      (u32)priv, (u32)priv, priv->len);
476 
477 	priv->bytes_to_transfer = priv->len;
478 	priv->bytes_to_receive = priv->len;
479 
480 	if (priv->len < 4)
481 		zynq_qspi_fill_tx_fifo(priv, priv->len);
482 	else
483 		zynq_qspi_fill_tx_fifo(priv, priv->fifo_depth);
484 
485 	writel(ZYNQ_QSPI_IXR_ALL_MASK, &regs->ier);
486 
487 	/* wait for completion */
488 	do {
489 		data = zynq_qspi_irq_poll(priv);
490 	} while (data == 0);
491 
492 	return (priv->len) - (priv->bytes_to_transfer);
493 }
494 
zynq_qspi_transfer(struct zynq_qspi_priv * priv)495 static int zynq_qspi_transfer(struct zynq_qspi_priv *priv)
496 {
497 	unsigned cs_change = 1;
498 	int status = 0;
499 
500 	while (1) {
501 		/* Select the chip if required */
502 		if (cs_change)
503 			zynq_qspi_chipselect(priv, 1);
504 
505 		cs_change = priv->cs_change;
506 
507 		if (!priv->tx_buf && !priv->rx_buf && priv->len) {
508 			status = -1;
509 			break;
510 		}
511 
512 		/* Request the transfer */
513 		if (priv->len) {
514 			status = zynq_qspi_start_transfer(priv);
515 			priv->is_inst = 0;
516 		}
517 
518 		if (status != priv->len) {
519 			if (status > 0)
520 				status = -EMSGSIZE;
521 			debug("zynq_qspi_transfer:%d len:%d\n",
522 			      status, priv->len);
523 			break;
524 		}
525 		status = 0;
526 
527 		if (cs_change)
528 			/* Deselect the chip */
529 			zynq_qspi_chipselect(priv, 0);
530 
531 		break;
532 	}
533 
534 	return status;
535 }
536 
zynq_qspi_claim_bus(struct udevice * dev)537 static int zynq_qspi_claim_bus(struct udevice *dev)
538 {
539 	struct udevice *bus = dev->parent;
540 	struct zynq_qspi_priv *priv = dev_get_priv(bus);
541 	struct zynq_qspi_regs *regs = priv->regs;
542 
543 	writel(ZYNQ_QSPI_ENR_SPI_EN_MASK, &regs->enr);
544 
545 	return 0;
546 }
547 
zynq_qspi_release_bus(struct udevice * dev)548 static int zynq_qspi_release_bus(struct udevice *dev)
549 {
550 	struct udevice *bus = dev->parent;
551 	struct zynq_qspi_priv *priv = dev_get_priv(bus);
552 	struct zynq_qspi_regs *regs = priv->regs;
553 
554 	writel(~ZYNQ_QSPI_ENR_SPI_EN_MASK, &regs->enr);
555 
556 	return 0;
557 }
558 
zynq_qspi_xfer(struct udevice * dev,unsigned int bitlen,const void * dout,void * din,unsigned long flags)559 static int zynq_qspi_xfer(struct udevice *dev, unsigned int bitlen,
560 		const void *dout, void *din, unsigned long flags)
561 {
562 	struct udevice *bus = dev->parent;
563 	struct zynq_qspi_priv *priv = dev_get_priv(bus);
564 	struct dm_spi_slave_plat *slave_plat = dev_get_parent_plat(dev);
565 
566 	priv->cs = slave_plat->cs;
567 	priv->tx_buf = dout;
568 	priv->rx_buf = din;
569 	priv->len = bitlen / 8;
570 
571 	debug("zynq_qspi_xfer: bus:%i cs:%i bitlen:%i len:%i flags:%lx\n",
572 	      dev_seq(bus), slave_plat->cs, bitlen, priv->len, flags);
573 
574 	/*
575 	 * Festering sore.
576 	 * Assume that the beginning of a transfer with bits to
577 	 * transmit must contain a device command.
578 	 */
579 	if (dout && flags & SPI_XFER_BEGIN)
580 		priv->is_inst = 1;
581 	else
582 		priv->is_inst = 0;
583 
584 	if (flags & SPI_XFER_END)
585 		priv->cs_change = 1;
586 	else
587 		priv->cs_change = 0;
588 
589 	zynq_qspi_transfer(priv);
590 
591 	return 0;
592 }
593 
zynq_qspi_set_speed(struct udevice * bus,uint speed)594 static int zynq_qspi_set_speed(struct udevice *bus, uint speed)
595 {
596 	struct zynq_qspi_plat *plat = dev_get_plat(bus);
597 	struct zynq_qspi_priv *priv = dev_get_priv(bus);
598 	struct zynq_qspi_regs *regs = priv->regs;
599 	uint32_t confr;
600 	u8 baud_rate_val = 0;
601 
602 	if (speed > plat->frequency)
603 		speed = plat->frequency;
604 
605 	/* Set the clock frequency */
606 	confr = readl(&regs->cr);
607 	if (speed == 0) {
608 		/* Set baudrate x8, if the freq is 0 */
609 		baud_rate_val = 0x2;
610 	} else if (plat->speed_hz != speed) {
611 		while ((baud_rate_val < ZYNQ_QSPI_CR_BAUD_MAX) &&
612 		       ((plat->frequency /
613 		       (2 << baud_rate_val)) > speed))
614 			baud_rate_val++;
615 
616 		plat->speed_hz = speed / (2 << baud_rate_val);
617 	}
618 	confr &= ~ZYNQ_QSPI_CR_BAUD_MASK;
619 	confr |= (baud_rate_val << ZYNQ_QSPI_CR_BAUD_SHIFT);
620 
621 	writel(confr, &regs->cr);
622 	priv->freq = speed;
623 
624 	debug("%s: regs=%p, speed=%d\n", __func__, priv->regs, priv->freq);
625 
626 	return 0;
627 }
628 
zynq_qspi_set_mode(struct udevice * bus,uint mode)629 static int zynq_qspi_set_mode(struct udevice *bus, uint mode)
630 {
631 	struct zynq_qspi_priv *priv = dev_get_priv(bus);
632 	struct zynq_qspi_regs *regs = priv->regs;
633 	uint32_t confr;
634 
635 	/* Set the SPI Clock phase and polarities */
636 	confr = readl(&regs->cr);
637 	confr &= ~(ZYNQ_QSPI_CR_CPHA_MASK | ZYNQ_QSPI_CR_CPOL_MASK);
638 
639 	if (mode & SPI_CPHA)
640 		confr |= ZYNQ_QSPI_CR_CPHA_MASK;
641 	if (mode & SPI_CPOL)
642 		confr |= ZYNQ_QSPI_CR_CPOL_MASK;
643 
644 	writel(confr, &regs->cr);
645 	priv->mode = mode;
646 
647 	debug("%s: regs=%p, mode=%d\n", __func__, priv->regs, priv->mode);
648 
649 	return 0;
650 }
651 
652 static const struct dm_spi_ops zynq_qspi_ops = {
653 	.claim_bus      = zynq_qspi_claim_bus,
654 	.release_bus    = zynq_qspi_release_bus,
655 	.xfer           = zynq_qspi_xfer,
656 	.set_speed      = zynq_qspi_set_speed,
657 	.set_mode       = zynq_qspi_set_mode,
658 };
659 
660 static const struct udevice_id zynq_qspi_ids[] = {
661 	{ .compatible = "xlnx,zynq-qspi-1.0" },
662 	{ }
663 };
664 
665 U_BOOT_DRIVER(zynq_qspi) = {
666 	.name   = "zynq_qspi",
667 	.id     = UCLASS_SPI,
668 	.of_match = zynq_qspi_ids,
669 	.ops    = &zynq_qspi_ops,
670 	.of_to_plat = zynq_qspi_of_to_plat,
671 	.plat_auto	= sizeof(struct zynq_qspi_plat),
672 	.priv_auto	= sizeof(struct zynq_qspi_priv),
673 	.probe  = zynq_qspi_probe,
674 };
675