xref: /openbmc/linux/drivers/spi/spi-zynqmp-gqspi.c (revision 4d75f5c664195b970e1cd2fd25b65b5eff257a0a)
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.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/spi/spi.h>
21 #include <linux/spinlock.h>
22 #include <linux/workqueue.h>
23 #include <linux/spi/spi-mem.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 IOU_TAPDLY_BYPASS_OFST		0x0000003C
37 #define GQSPI_LPBK_DLY_ADJ_OFST		0x00000138
38 #define GQSPI_GEN_FIFO_OFST		0x00000140
39 #define GQSPI_SEL_OFST			0x00000144
40 #define GQSPI_GF_THRESHOLD_OFST		0x00000150
41 #define GQSPI_FIFO_CTRL_OFST		0x0000014C
42 #define GQSPI_QSPIDMA_DST_CTRL_OFST	0x0000080C
43 #define GQSPI_QSPIDMA_DST_SIZE_OFST	0x00000804
44 #define GQSPI_QSPIDMA_DST_STS_OFST	0x00000808
45 #define GQSPI_QSPIDMA_DST_I_STS_OFST	0x00000814
46 #define GQSPI_QSPIDMA_DST_I_EN_OFST	0x00000818
47 #define GQSPI_QSPIDMA_DST_I_DIS_OFST	0x0000081C
48 #define GQSPI_QSPIDMA_DST_I_MASK_OFST	0x00000820
49 #define GQSPI_QSPIDMA_DST_ADDR_OFST	0x00000800
50 #define GQSPI_QSPIDMA_DST_ADDR_MSB_OFST 0x00000828
51 #define GQSPI_DATA_DLY_ADJ_OFST         0x000001F8
52 
53 /* GQSPI register bit masks */
54 #define GQSPI_SEL_MASK				0x00000001
55 #define GQSPI_EN_MASK				0x00000001
56 #define GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK	0x00000020
57 #define GQSPI_ISR_WR_TO_CLR_MASK		0x00000002
58 #define GQSPI_IDR_ALL_MASK			0x00000FBE
59 #define GQSPI_CFG_MODE_EN_MASK			0xC0000000
60 #define GQSPI_CFG_GEN_FIFO_START_MODE_MASK	0x20000000
61 #define GQSPI_CFG_ENDIAN_MASK			0x04000000
62 #define GQSPI_CFG_EN_POLL_TO_MASK		0x00100000
63 #define GQSPI_CFG_WP_HOLD_MASK			0x00080000
64 #define GQSPI_CFG_BAUD_RATE_DIV_MASK		0x00000038
65 #define GQSPI_CFG_CLK_PHA_MASK			0x00000004
66 #define GQSPI_CFG_CLK_POL_MASK			0x00000002
67 #define GQSPI_CFG_START_GEN_FIFO_MASK		0x10000000
68 #define GQSPI_GENFIFO_IMM_DATA_MASK		0x000000FF
69 #define GQSPI_GENFIFO_DATA_XFER			0x00000100
70 #define GQSPI_GENFIFO_EXP			0x00000200
71 #define GQSPI_GENFIFO_MODE_SPI			0x00000400
72 #define GQSPI_GENFIFO_MODE_DUALSPI		0x00000800
73 #define GQSPI_GENFIFO_MODE_QUADSPI		0x00000C00
74 #define GQSPI_GENFIFO_MODE_MASK			0x00000C00
75 #define GQSPI_GENFIFO_CS_LOWER			0x00001000
76 #define GQSPI_GENFIFO_CS_UPPER			0x00002000
77 #define GQSPI_GENFIFO_BUS_LOWER			0x00004000
78 #define GQSPI_GENFIFO_BUS_UPPER			0x00008000
79 #define GQSPI_GENFIFO_BUS_BOTH			0x0000C000
80 #define GQSPI_GENFIFO_BUS_MASK			0x0000C000
81 #define GQSPI_GENFIFO_TX			0x00010000
82 #define GQSPI_GENFIFO_RX			0x00020000
83 #define GQSPI_GENFIFO_STRIPE			0x00040000
84 #define GQSPI_GENFIFO_POLL			0x00080000
85 #define GQSPI_GENFIFO_EXP_START			0x00000100
86 #define GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK	0x00000004
87 #define GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK	0x00000002
88 #define GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK	0x00000001
89 #define GQSPI_ISR_RXEMPTY_MASK			0x00000800
90 #define GQSPI_ISR_GENFIFOFULL_MASK		0x00000400
91 #define GQSPI_ISR_GENFIFONOT_FULL_MASK		0x00000200
92 #define GQSPI_ISR_TXEMPTY_MASK			0x00000100
93 #define GQSPI_ISR_GENFIFOEMPTY_MASK		0x00000080
94 #define GQSPI_ISR_RXFULL_MASK			0x00000020
95 #define GQSPI_ISR_RXNEMPTY_MASK			0x00000010
96 #define GQSPI_ISR_TXFULL_MASK			0x00000008
97 #define GQSPI_ISR_TXNOT_FULL_MASK		0x00000004
98 #define GQSPI_ISR_POLL_TIME_EXPIRE_MASK		0x00000002
99 #define GQSPI_IER_TXNOT_FULL_MASK		0x00000004
100 #define GQSPI_IER_RXEMPTY_MASK			0x00000800
101 #define GQSPI_IER_POLL_TIME_EXPIRE_MASK		0x00000002
102 #define GQSPI_IER_RXNEMPTY_MASK			0x00000010
103 #define GQSPI_IER_GENFIFOEMPTY_MASK		0x00000080
104 #define GQSPI_IER_TXEMPTY_MASK			0x00000100
105 #define GQSPI_QSPIDMA_DST_INTR_ALL_MASK		0x000000FE
106 #define GQSPI_QSPIDMA_DST_STS_WTC		0x0000E000
107 #define GQSPI_CFG_MODE_EN_DMA_MASK		0x80000000
108 #define GQSPI_ISR_IDR_MASK			0x00000994
109 #define GQSPI_QSPIDMA_DST_I_EN_DONE_MASK	0x00000002
110 #define GQSPI_QSPIDMA_DST_I_STS_DONE_MASK	0x00000002
111 #define GQSPI_IRQ_MASK				0x00000980
112 
113 #define GQSPI_CFG_BAUD_RATE_DIV_SHIFT		3
114 #define GQSPI_GENFIFO_CS_SETUP			0x4
115 #define GQSPI_GENFIFO_CS_HOLD			0x3
116 #define GQSPI_TXD_DEPTH				64
117 #define GQSPI_RX_FIFO_THRESHOLD			32
118 #define GQSPI_RX_FIFO_FILL	(GQSPI_RX_FIFO_THRESHOLD * 4)
119 #define GQSPI_TX_FIFO_THRESHOLD_RESET_VAL	32
120 #define GQSPI_TX_FIFO_FILL	(GQSPI_TXD_DEPTH -\
121 				GQSPI_TX_FIFO_THRESHOLD_RESET_VAL)
122 #define GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL	0X10
123 #define GQSPI_QSPIDMA_DST_CTRL_RESET_VAL	0x803FFA00
124 #define GQSPI_SELECT_FLASH_CS_LOWER		0x1
125 #define GQSPI_SELECT_FLASH_CS_UPPER		0x2
126 #define GQSPI_SELECT_FLASH_CS_BOTH		0x3
127 #define GQSPI_SELECT_FLASH_BUS_LOWER		0x1
128 #define GQSPI_SELECT_FLASH_BUS_UPPER		0x2
129 #define GQSPI_SELECT_FLASH_BUS_BOTH		0x3
130 #define GQSPI_BAUD_DIV_MAX	7	/* Baud rate divisor maximum */
131 #define GQSPI_BAUD_DIV_SHIFT	2	/* Baud rate divisor shift */
132 #define GQSPI_SELECT_MODE_SPI		0x1
133 #define GQSPI_SELECT_MODE_DUALSPI	0x2
134 #define GQSPI_SELECT_MODE_QUADSPI	0x4
135 #define GQSPI_DMA_UNALIGN		0x3
136 #define GQSPI_DEFAULT_NUM_CS	1	/* Default number of chip selects */
137 
138 #define GQSPI_MAX_NUM_CS	2	/* Maximum number of chip selects */
139 
140 #define GQSPI_USE_DATA_DLY		0x1
141 #define GQSPI_USE_DATA_DLY_SHIFT	31
142 #define GQSPI_DATA_DLY_ADJ_VALUE	0x2
143 #define GQSPI_DATA_DLY_ADJ_SHIFT	28
144 #define GQSPI_LPBK_DLY_ADJ_DLY_1	0x1
145 #define GQSPI_LPBK_DLY_ADJ_DLY_1_SHIFT	0x3
146 #define TAP_DLY_BYPASS_LQSPI_RX_VALUE	0x1
147 #define TAP_DLY_BYPASS_LQSPI_RX_SHIFT	0x2
148 
149 /* set to differentiate versal from zynqmp, 1=versal, 0=zynqmp */
150 #define QSPI_QUIRK_HAS_TAPDELAY		BIT(0)
151 
152 #define GQSPI_FREQ_37_5MHZ	37500000
153 #define GQSPI_FREQ_40MHZ	40000000
154 #define GQSPI_FREQ_100MHZ	100000000
155 #define GQSPI_FREQ_150MHZ	150000000
156 
157 #define SPI_AUTOSUSPEND_TIMEOUT		3000
158 enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
159 
160 /**
161  * struct qspi_platform_data - zynqmp qspi platform data structure
162  * @quirks:    Flags is used to identify the platform
163  */
164 struct qspi_platform_data {
165 	u32 quirks;
166 };
167 
168 /**
169  * struct zynqmp_qspi - Defines qspi driver instance
170  * @ctlr:		Pointer to the spi controller information
171  * @regs:		Virtual address of the QSPI controller registers
172  * @refclk:		Pointer to the peripheral clock
173  * @pclk:		Pointer to the APB clock
174  * @irq:		IRQ number
175  * @dev:		Pointer to struct device
176  * @txbuf:		Pointer to the TX buffer
177  * @rxbuf:		Pointer to the RX buffer
178  * @bytes_to_transfer:	Number of bytes left to transfer
179  * @bytes_to_receive:	Number of bytes left to receive
180  * @genfifocs:		Used for chip select
181  * @genfifobus:		Used to select the upper or lower bus
182  * @dma_rx_bytes:	Remaining bytes to receive by DMA mode
183  * @dma_addr:		DMA address after mapping the kernel buffer
184  * @genfifoentry:	Used for storing the genfifoentry instruction.
185  * @mode:		Defines the mode in which QSPI is operating
186  * @data_completion:	completion structure
187  * @op_lock:		Operational lock
188  * @speed_hz:          Current SPI bus clock speed in hz
189  * @has_tapdelay:	Used for tapdelay register available in qspi
190  */
191 struct zynqmp_qspi {
192 	struct spi_controller *ctlr;
193 	void __iomem *regs;
194 	struct clk *refclk;
195 	struct clk *pclk;
196 	int irq;
197 	struct device *dev;
198 	const void *txbuf;
199 	void *rxbuf;
200 	int bytes_to_transfer;
201 	int bytes_to_receive;
202 	u32 genfifocs;
203 	u32 genfifobus;
204 	u32 dma_rx_bytes;
205 	dma_addr_t dma_addr;
206 	u32 genfifoentry;
207 	enum mode_type mode;
208 	struct completion data_completion;
209 	struct mutex op_lock;
210 	u32 speed_hz;
211 	bool has_tapdelay;
212 };
213 
214 /**
215  * zynqmp_gqspi_read - For GQSPI controller read operation
216  * @xqspi:	Pointer to the zynqmp_qspi structure
217  * @offset:	Offset from where to read
218  * Return:      Value at the offset
219  */
zynqmp_gqspi_read(struct zynqmp_qspi * xqspi,u32 offset)220 static u32 zynqmp_gqspi_read(struct zynqmp_qspi *xqspi, u32 offset)
221 {
222 	return readl_relaxed(xqspi->regs + offset);
223 }
224 
225 /**
226  * zynqmp_gqspi_write - For GQSPI controller write operation
227  * @xqspi:	Pointer to the zynqmp_qspi structure
228  * @offset:	Offset where to write
229  * @val:	Value to be written
230  */
zynqmp_gqspi_write(struct zynqmp_qspi * xqspi,u32 offset,u32 val)231 static inline void zynqmp_gqspi_write(struct zynqmp_qspi *xqspi, u32 offset,
232 				      u32 val)
233 {
234 	writel_relaxed(val, (xqspi->regs + offset));
235 }
236 
237 /**
238  * zynqmp_gqspi_selectslave - For selection of slave device
239  * @instanceptr:	Pointer to the zynqmp_qspi structure
240  * @slavecs:	For chip select
241  * @slavebus:	To check which bus is selected- upper or lower
242  */
zynqmp_gqspi_selectslave(struct zynqmp_qspi * instanceptr,u8 slavecs,u8 slavebus)243 static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
244 				     u8 slavecs, u8 slavebus)
245 {
246 	/*
247 	 * Bus and CS lines selected here will be updated in the instance and
248 	 * used for subsequent GENFIFO entries during transfer.
249 	 */
250 
251 	/* Choose slave select line */
252 	switch (slavecs) {
253 	case GQSPI_SELECT_FLASH_CS_BOTH:
254 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER |
255 			GQSPI_GENFIFO_CS_UPPER;
256 		break;
257 	case GQSPI_SELECT_FLASH_CS_UPPER:
258 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_UPPER;
259 		break;
260 	case GQSPI_SELECT_FLASH_CS_LOWER:
261 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER;
262 		break;
263 	default:
264 		dev_warn(instanceptr->dev, "Invalid slave select\n");
265 	}
266 
267 	/* Choose the bus */
268 	switch (slavebus) {
269 	case GQSPI_SELECT_FLASH_BUS_BOTH:
270 		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER |
271 			GQSPI_GENFIFO_BUS_UPPER;
272 		break;
273 	case GQSPI_SELECT_FLASH_BUS_UPPER:
274 		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_UPPER;
275 		break;
276 	case GQSPI_SELECT_FLASH_BUS_LOWER:
277 		instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER;
278 		break;
279 	default:
280 		dev_warn(instanceptr->dev, "Invalid slave bus\n");
281 	}
282 }
283 
284 /**
285  * zynqmp_qspi_set_tapdelay:   To configure qspi tap delays
286  * @xqspi:             Pointer to the zynqmp_qspi structure
287  * @baudrateval:       Buadrate to configure
288  */
zynqmp_qspi_set_tapdelay(struct zynqmp_qspi * xqspi,u32 baudrateval)289 static void zynqmp_qspi_set_tapdelay(struct zynqmp_qspi *xqspi, u32 baudrateval)
290 {
291 	u32 tapdlybypass = 0, lpbkdlyadj = 0, datadlyadj = 0, clk_rate;
292 	u32 reqhz = 0;
293 
294 	clk_rate = clk_get_rate(xqspi->refclk);
295 	reqhz = (clk_rate / (GQSPI_BAUD_DIV_SHIFT << baudrateval));
296 
297 	if (!xqspi->has_tapdelay) {
298 		if (reqhz <= GQSPI_FREQ_40MHZ) {
299 			zynqmp_pm_set_tapdelay_bypass(PM_TAPDELAY_QSPI,
300 						      PM_TAPDELAY_BYPASS_ENABLE);
301 		} else if (reqhz <= GQSPI_FREQ_100MHZ) {
302 			zynqmp_pm_set_tapdelay_bypass(PM_TAPDELAY_QSPI,
303 						      PM_TAPDELAY_BYPASS_ENABLE);
304 			lpbkdlyadj |= (GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK);
305 			datadlyadj |= ((GQSPI_USE_DATA_DLY <<
306 					GQSPI_USE_DATA_DLY_SHIFT)
307 					| (GQSPI_DATA_DLY_ADJ_VALUE <<
308 						GQSPI_DATA_DLY_ADJ_SHIFT));
309 		} else if (reqhz <= GQSPI_FREQ_150MHZ) {
310 			lpbkdlyadj |= GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK;
311 		}
312 	} else {
313 		if (reqhz <= GQSPI_FREQ_37_5MHZ) {
314 			tapdlybypass |= (TAP_DLY_BYPASS_LQSPI_RX_VALUE <<
315 					TAP_DLY_BYPASS_LQSPI_RX_SHIFT);
316 		} else if (reqhz <= GQSPI_FREQ_100MHZ) {
317 			tapdlybypass |= (TAP_DLY_BYPASS_LQSPI_RX_VALUE <<
318 					TAP_DLY_BYPASS_LQSPI_RX_SHIFT);
319 			lpbkdlyadj |= (GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK);
320 			datadlyadj |= (GQSPI_USE_DATA_DLY <<
321 					GQSPI_USE_DATA_DLY_SHIFT);
322 		} else if (reqhz <= GQSPI_FREQ_150MHZ) {
323 			lpbkdlyadj |= (GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK
324 				       | (GQSPI_LPBK_DLY_ADJ_DLY_1 <<
325 					       GQSPI_LPBK_DLY_ADJ_DLY_1_SHIFT));
326 		}
327 		zynqmp_gqspi_write(xqspi,
328 				   IOU_TAPDLY_BYPASS_OFST, tapdlybypass);
329 	}
330 	zynqmp_gqspi_write(xqspi, GQSPI_LPBK_DLY_ADJ_OFST, lpbkdlyadj);
331 	zynqmp_gqspi_write(xqspi, GQSPI_DATA_DLY_ADJ_OFST, datadlyadj);
332 }
333 
334 /**
335  * zynqmp_qspi_init_hw - Initialize the hardware
336  * @xqspi:	Pointer to the zynqmp_qspi structure
337  *
338  * The default settings of the QSPI controller's configurable parameters on
339  * reset are
340  *	- Master mode
341  *	- TX threshold set to 1
342  *	- RX threshold set to 1
343  *	- Flash memory interface mode enabled
344  * This function performs the following actions
345  *	- Disable and clear all the interrupts
346  *	- Enable manual slave select
347  *	- Enable manual start
348  *	- Deselect all the chip select lines
349  *	- Set the little endian mode of TX FIFO
350  *	- Set clock phase
351  *	- Set clock polarity and
352  *	- Enable the QSPI controller
353  */
zynqmp_qspi_init_hw(struct zynqmp_qspi * xqspi)354 static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
355 {
356 	u32 config_reg, baud_rate_val = 0;
357 	ulong clk_rate;
358 
359 	/* Select the GQSPI mode */
360 	zynqmp_gqspi_write(xqspi, GQSPI_SEL_OFST, GQSPI_SEL_MASK);
361 	/* Clear and disable interrupts */
362 	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST,
363 			   zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST) |
364 			   GQSPI_ISR_WR_TO_CLR_MASK);
365 	/* Clear the DMA STS */
366 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
367 			   zynqmp_gqspi_read(xqspi,
368 					     GQSPI_QSPIDMA_DST_I_STS_OFST));
369 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_STS_OFST,
370 			   zynqmp_gqspi_read(xqspi,
371 					     GQSPI_QSPIDMA_DST_STS_OFST) |
372 					     GQSPI_QSPIDMA_DST_STS_WTC);
373 	zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_IDR_ALL_MASK);
374 	zynqmp_gqspi_write(xqspi,
375 			   GQSPI_QSPIDMA_DST_I_DIS_OFST,
376 			   GQSPI_QSPIDMA_DST_INTR_ALL_MASK);
377 	/* Disable the GQSPI */
378 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
379 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
380 	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
381 	/* Manual start */
382 	config_reg |= GQSPI_CFG_GEN_FIFO_START_MODE_MASK;
383 	/* Little endian by default */
384 	config_reg &= ~GQSPI_CFG_ENDIAN_MASK;
385 	/* Disable poll time out */
386 	config_reg &= ~GQSPI_CFG_EN_POLL_TO_MASK;
387 	/* Set hold bit */
388 	config_reg |= GQSPI_CFG_WP_HOLD_MASK;
389 	/* Clear pre-scalar by default */
390 	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
391 	/* Set CPHA */
392 	if (xqspi->ctlr->mode_bits & SPI_CPHA)
393 		config_reg |= GQSPI_CFG_CLK_PHA_MASK;
394 	else
395 		config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
396 	/* Set CPOL */
397 	if (xqspi->ctlr->mode_bits & SPI_CPOL)
398 		config_reg |= GQSPI_CFG_CLK_POL_MASK;
399 	else
400 		config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
401 
402 	/* Set the clock frequency */
403 	clk_rate = clk_get_rate(xqspi->refclk);
404 	while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
405 	       (clk_rate /
406 		(GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > xqspi->speed_hz)
407 		baud_rate_val++;
408 
409 	config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
410 	config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
411 
412 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
413 
414 	/* Set the tapdelay for clock frequency */
415 	zynqmp_qspi_set_tapdelay(xqspi, baud_rate_val);
416 
417 	/* Clear the TX and RX FIFO */
418 	zynqmp_gqspi_write(xqspi, GQSPI_FIFO_CTRL_OFST,
419 			   GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK |
420 			   GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK |
421 			   GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK);
422 	/* Reset thresholds */
423 	zynqmp_gqspi_write(xqspi, GQSPI_TX_THRESHOLD_OFST,
424 			   GQSPI_TX_FIFO_THRESHOLD_RESET_VAL);
425 	zynqmp_gqspi_write(xqspi, GQSPI_RX_THRESHOLD_OFST,
426 			   GQSPI_RX_FIFO_THRESHOLD);
427 	zynqmp_gqspi_write(xqspi, GQSPI_GF_THRESHOLD_OFST,
428 			   GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL);
429 	zynqmp_gqspi_selectslave(xqspi,
430 				 GQSPI_SELECT_FLASH_CS_LOWER,
431 				 GQSPI_SELECT_FLASH_BUS_LOWER);
432 	/* Initialize DMA */
433 	zynqmp_gqspi_write(xqspi,
434 			   GQSPI_QSPIDMA_DST_CTRL_OFST,
435 			   GQSPI_QSPIDMA_DST_CTRL_RESET_VAL);
436 
437 	/* Enable the GQSPI */
438 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
439 }
440 
441 /**
442  * zynqmp_qspi_copy_read_data - Copy data to RX buffer
443  * @xqspi:	Pointer to the zynqmp_qspi structure
444  * @data:	The variable where data is stored
445  * @size:	Number of bytes to be copied from data to RX buffer
446  */
zynqmp_qspi_copy_read_data(struct zynqmp_qspi * xqspi,ulong data,u8 size)447 static void zynqmp_qspi_copy_read_data(struct zynqmp_qspi *xqspi,
448 				       ulong data, u8 size)
449 {
450 	memcpy(xqspi->rxbuf, &data, size);
451 	xqspi->rxbuf += size;
452 	xqspi->bytes_to_receive -= size;
453 }
454 
455 /**
456  * zynqmp_qspi_chipselect - Select or deselect the chip select line
457  * @qspi:	Pointer to the spi_device structure
458  * @is_high:	Select(0) or deselect (1) the chip select line
459  */
zynqmp_qspi_chipselect(struct spi_device * qspi,bool is_high)460 static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high)
461 {
462 	struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
463 	ulong timeout;
464 	u32 genfifoentry = 0, statusreg;
465 
466 	genfifoentry |= GQSPI_GENFIFO_MODE_SPI;
467 
468 	if (!is_high) {
469 		if (!spi_get_chipselect(qspi, 0)) {
470 			xqspi->genfifobus = GQSPI_GENFIFO_BUS_LOWER;
471 			xqspi->genfifocs = GQSPI_GENFIFO_CS_LOWER;
472 		} else {
473 			xqspi->genfifobus = GQSPI_GENFIFO_BUS_UPPER;
474 			xqspi->genfifocs = GQSPI_GENFIFO_CS_UPPER;
475 		}
476 		genfifoentry |= xqspi->genfifobus;
477 		genfifoentry |= xqspi->genfifocs;
478 		genfifoentry |= GQSPI_GENFIFO_CS_SETUP;
479 	} else {
480 		genfifoentry |= GQSPI_GENFIFO_CS_HOLD;
481 	}
482 
483 	zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
484 
485 	/* Manually start the generic FIFO command */
486 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
487 			   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
488 			   GQSPI_CFG_START_GEN_FIFO_MASK);
489 
490 	timeout = jiffies + msecs_to_jiffies(1000);
491 
492 	/* Wait until the generic FIFO command is empty */
493 	do {
494 		statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
495 
496 		if ((statusreg & GQSPI_ISR_GENFIFOEMPTY_MASK) &&
497 		    (statusreg & GQSPI_ISR_TXEMPTY_MASK))
498 			break;
499 		cpu_relax();
500 	} while (!time_after_eq(jiffies, timeout));
501 
502 	if (time_after_eq(jiffies, timeout))
503 		dev_err(xqspi->dev, "Chip select timed out\n");
504 }
505 
506 /**
507  * zynqmp_qspi_selectspimode - Selects SPI mode - x1 or x2 or x4.
508  * @xqspi:	xqspi is a pointer to the GQSPI instance
509  * @spimode:	spimode - SPI or DUAL or QUAD.
510  * Return:	Mask to set desired SPI mode in GENFIFO entry.
511  */
zynqmp_qspi_selectspimode(struct zynqmp_qspi * xqspi,u8 spimode)512 static inline u32 zynqmp_qspi_selectspimode(struct zynqmp_qspi *xqspi,
513 					    u8 spimode)
514 {
515 	u32 mask = 0;
516 
517 	switch (spimode) {
518 	case GQSPI_SELECT_MODE_DUALSPI:
519 		mask = GQSPI_GENFIFO_MODE_DUALSPI;
520 		break;
521 	case GQSPI_SELECT_MODE_QUADSPI:
522 		mask = GQSPI_GENFIFO_MODE_QUADSPI;
523 		break;
524 	case GQSPI_SELECT_MODE_SPI:
525 		mask = GQSPI_GENFIFO_MODE_SPI;
526 		break;
527 	default:
528 		dev_warn(xqspi->dev, "Invalid SPI mode\n");
529 	}
530 
531 	return mask;
532 }
533 
534 /**
535  * zynqmp_qspi_config_op - Configure QSPI controller for specified
536  *				transfer
537  * @xqspi:	Pointer to the zynqmp_qspi structure
538  * @qspi:	Pointer to the spi_device structure
539  *
540  * Sets the operational mode of QSPI controller for the next QSPI transfer and
541  * sets the requested clock frequency.
542  *
543  * Return:	Always 0
544  *
545  * Note:
546  *	If the requested frequency is not an exact match with what can be
547  *	obtained using the pre-scalar value, the driver sets the clock
548  *	frequency which is lower than the requested frequency (maximum lower)
549  *	for the transfer.
550  *
551  *	If the requested frequency is higher or lower than that is supported
552  *	by the QSPI controller the driver will set the highest or lowest
553  *	frequency supported by controller.
554  */
zynqmp_qspi_config_op(struct zynqmp_qspi * xqspi,struct spi_device * qspi)555 static int zynqmp_qspi_config_op(struct zynqmp_qspi *xqspi,
556 				 struct spi_device *qspi)
557 {
558 	ulong clk_rate;
559 	u32 config_reg, req_speed_hz, baud_rate_val = 0;
560 
561 	req_speed_hz = qspi->max_speed_hz;
562 
563 	if (xqspi->speed_hz != req_speed_hz) {
564 		xqspi->speed_hz = req_speed_hz;
565 
566 		/* Set the clock frequency */
567 		/* If req_speed_hz == 0, default to lowest speed */
568 		clk_rate = clk_get_rate(xqspi->refclk);
569 
570 		while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
571 		       (clk_rate /
572 			(GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) >
573 		       req_speed_hz)
574 			baud_rate_val++;
575 
576 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
577 
578 		config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
579 		config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
580 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
581 		zynqmp_qspi_set_tapdelay(xqspi, baud_rate_val);
582 	}
583 	return 0;
584 }
585 
586 /**
587  * zynqmp_qspi_setup_op - Configure the QSPI controller
588  * @qspi:	Pointer to the spi_device structure
589  *
590  * Sets the operational mode of QSPI controller for the next QSPI transfer,
591  * baud rate and divisor value to setup the requested qspi clock.
592  *
593  * Return:	0 on success; error value otherwise.
594  */
zynqmp_qspi_setup_op(struct spi_device * qspi)595 static int zynqmp_qspi_setup_op(struct spi_device *qspi)
596 {
597 	struct spi_controller *ctlr = qspi->master;
598 	struct zynqmp_qspi *xqspi = spi_controller_get_devdata(ctlr);
599 
600 	if (ctlr->busy)
601 		return -EBUSY;
602 
603 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
604 
605 	return 0;
606 }
607 
608 /**
609  * zynqmp_qspi_filltxfifo - Fills the TX FIFO as long as there is room in
610  *				the FIFO or the bytes required to be
611  *				transmitted.
612  * @xqspi:	Pointer to the zynqmp_qspi structure
613  * @size:	Number of bytes to be copied from TX buffer to TX FIFO
614  */
zynqmp_qspi_filltxfifo(struct zynqmp_qspi * xqspi,int size)615 static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
616 {
617 	u32 count = 0, intermediate;
618 
619 	while ((xqspi->bytes_to_transfer > 0) && (count < size) && (xqspi->txbuf)) {
620 		if (xqspi->bytes_to_transfer >= 4) {
621 			memcpy(&intermediate, xqspi->txbuf, 4);
622 			xqspi->txbuf += 4;
623 			xqspi->bytes_to_transfer -= 4;
624 			count += 4;
625 		} else {
626 			memcpy(&intermediate, xqspi->txbuf,
627 			       xqspi->bytes_to_transfer);
628 			xqspi->txbuf += xqspi->bytes_to_transfer;
629 			xqspi->bytes_to_transfer = 0;
630 			count += xqspi->bytes_to_transfer;
631 		}
632 		zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
633 	}
634 }
635 
636 /**
637  * zynqmp_qspi_readrxfifo - Fills the RX FIFO as long as there is room in
638  *				the FIFO.
639  * @xqspi:	Pointer to the zynqmp_qspi structure
640  * @size:	Number of bytes to be copied from RX buffer to RX FIFO
641  */
zynqmp_qspi_readrxfifo(struct zynqmp_qspi * xqspi,u32 size)642 static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
643 {
644 	ulong data;
645 	int count = 0;
646 
647 	while ((count < size) && (xqspi->bytes_to_receive > 0)) {
648 		if (xqspi->bytes_to_receive >= 4) {
649 			(*(u32 *)xqspi->rxbuf) =
650 			zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
651 			xqspi->rxbuf += 4;
652 			xqspi->bytes_to_receive -= 4;
653 			count += 4;
654 		} else {
655 			data = zynqmp_gqspi_read(xqspi, GQSPI_RXD_OFST);
656 			count += xqspi->bytes_to_receive;
657 			zynqmp_qspi_copy_read_data(xqspi, data,
658 						   xqspi->bytes_to_receive);
659 			xqspi->bytes_to_receive = 0;
660 		}
661 	}
662 }
663 
664 /**
665  * zynqmp_qspi_fillgenfifo - Fills the GENFIFO.
666  * @xqspi:	Pointer to the zynqmp_qspi structure
667  * @nbits:	Transfer/Receive buswidth.
668  * @genfifoentry:       Variable in which GENFIFO mask is saved
669  */
zynqmp_qspi_fillgenfifo(struct zynqmp_qspi * xqspi,u8 nbits,u32 genfifoentry)670 static void zynqmp_qspi_fillgenfifo(struct zynqmp_qspi *xqspi, u8 nbits,
671 				    u32 genfifoentry)
672 {
673 	u32 transfer_len = 0;
674 
675 	if (xqspi->txbuf) {
676 		genfifoentry &= ~GQSPI_GENFIFO_RX;
677 		genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
678 		genfifoentry |= GQSPI_GENFIFO_TX;
679 		transfer_len = xqspi->bytes_to_transfer;
680 	} else if (xqspi->rxbuf) {
681 		genfifoentry &= ~GQSPI_GENFIFO_TX;
682 		genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
683 		genfifoentry |= GQSPI_GENFIFO_RX;
684 		if (xqspi->mode == GQSPI_MODE_DMA)
685 			transfer_len = xqspi->dma_rx_bytes;
686 		else
687 			transfer_len = xqspi->bytes_to_receive;
688 	} else {
689 		/* Sending dummy circles here */
690 		genfifoentry &= ~(GQSPI_GENFIFO_TX | GQSPI_GENFIFO_RX);
691 		genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
692 		transfer_len = xqspi->bytes_to_transfer;
693 	}
694 	genfifoentry |= zynqmp_qspi_selectspimode(xqspi, nbits);
695 	xqspi->genfifoentry = genfifoentry;
696 
697 	if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {
698 		genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
699 		genfifoentry |= transfer_len;
700 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
701 	} else {
702 		int tempcount = transfer_len;
703 		u32 exponent = 8;	/* 2^8 = 256 */
704 		u8 imm_data = tempcount & 0xFF;
705 
706 		tempcount &= ~(tempcount & 0xFF);
707 		/* Immediate entry */
708 		if (tempcount != 0) {
709 			/* Exponent entries */
710 			genfifoentry |= GQSPI_GENFIFO_EXP;
711 			while (tempcount != 0) {
712 				if (tempcount & GQSPI_GENFIFO_EXP_START) {
713 					genfifoentry &=
714 						~GQSPI_GENFIFO_IMM_DATA_MASK;
715 					genfifoentry |= exponent;
716 					zynqmp_gqspi_write(xqspi,
717 							   GQSPI_GEN_FIFO_OFST,
718 							   genfifoentry);
719 				}
720 				tempcount = tempcount >> 1;
721 				exponent++;
722 			}
723 		}
724 		if (imm_data != 0) {
725 			genfifoentry &= ~GQSPI_GENFIFO_EXP;
726 			genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
727 			genfifoentry |= (u8)(imm_data & 0xFF);
728 			zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST,
729 					   genfifoentry);
730 		}
731 	}
732 	if (xqspi->mode == GQSPI_MODE_IO && xqspi->rxbuf) {
733 		/* Dummy generic FIFO entry */
734 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
735 	}
736 }
737 
738 /**
739  * zynqmp_process_dma_irq - Handler for DMA done interrupt of QSPI
740  *				controller
741  * @xqspi:	zynqmp_qspi instance pointer
742  *
743  * This function handles DMA interrupt only.
744  */
zynqmp_process_dma_irq(struct zynqmp_qspi * xqspi)745 static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
746 {
747 	u32 config_reg, genfifoentry;
748 
749 	dma_unmap_single(xqspi->dev, xqspi->dma_addr,
750 			 xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
751 	xqspi->rxbuf += xqspi->dma_rx_bytes;
752 	xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
753 	xqspi->dma_rx_bytes = 0;
754 
755 	/* Disabling the DMA interrupts */
756 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_DIS_OFST,
757 			   GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
758 
759 	if (xqspi->bytes_to_receive > 0) {
760 		/* Switch to IO mode,for remaining bytes to receive */
761 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
762 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
763 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
764 
765 		/* Initiate the transfer of remaining bytes */
766 		genfifoentry = xqspi->genfifoentry;
767 		genfifoentry |= xqspi->bytes_to_receive;
768 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
769 
770 		/* Dummy generic FIFO entry */
771 		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);
772 
773 		/* Manual start */
774 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
775 				   (zynqmp_gqspi_read(xqspi,
776 						      GQSPI_CONFIG_OFST) |
777 				   GQSPI_CFG_START_GEN_FIFO_MASK));
778 
779 		/* Enable the RX interrupts for IO mode */
780 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
781 				   GQSPI_IER_GENFIFOEMPTY_MASK |
782 				   GQSPI_IER_RXNEMPTY_MASK |
783 				   GQSPI_IER_RXEMPTY_MASK);
784 	}
785 }
786 
787 /**
788  * zynqmp_qspi_irq - Interrupt service routine of the QSPI controller
789  * @irq:	IRQ number
790  * @dev_id:	Pointer to the xqspi structure
791  *
792  * This function handles TX empty only.
793  * On TX empty interrupt this function reads the received data from RX FIFO
794  * and fills the TX FIFO if there is any data remaining to be transferred.
795  *
796  * Return:	IRQ_HANDLED when interrupt is handled
797  *		IRQ_NONE otherwise.
798  */
zynqmp_qspi_irq(int irq,void * dev_id)799 static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
800 {
801 	struct zynqmp_qspi *xqspi = (struct zynqmp_qspi *)dev_id;
802 	u32 status, mask, dma_status = 0;
803 
804 	status = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
805 	zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST, status);
806 	mask = (status & ~(zynqmp_gqspi_read(xqspi, GQSPI_IMASK_OFST)));
807 
808 	/* Read and clear DMA status */
809 	if (xqspi->mode == GQSPI_MODE_DMA) {
810 		dma_status =
811 			zynqmp_gqspi_read(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST);
812 		zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
813 				   dma_status);
814 	}
815 
816 	if (!mask && !dma_status)
817 		return IRQ_NONE;
818 
819 	if (mask & GQSPI_ISR_TXNOT_FULL_MASK)
820 		zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
821 
822 	if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK)
823 		zynqmp_process_dma_irq(xqspi);
824 	else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
825 			(mask & GQSPI_IER_GENFIFOEMPTY_MASK))
826 		zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
827 
828 	if (xqspi->bytes_to_receive == 0 && xqspi->bytes_to_transfer == 0 &&
829 	    ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
830 		zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_ISR_IDR_MASK);
831 		complete(&xqspi->data_completion);
832 	}
833 	return IRQ_HANDLED;
834 }
835 
836 /**
837  * zynqmp_qspi_setuprxdma - This function sets up the RX DMA operation
838  * @xqspi:	xqspi is a pointer to the GQSPI instance.
839  *
840  * Return:	0 on success; error value otherwise.
841  */
zynqmp_qspi_setuprxdma(struct zynqmp_qspi * xqspi)842 static int zynqmp_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
843 {
844 	u32 rx_bytes, rx_rem, config_reg;
845 	dma_addr_t addr;
846 	u64 dma_align =  (u64)(uintptr_t)xqspi->rxbuf;
847 
848 	if (xqspi->bytes_to_receive < 8 ||
849 	    ((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
850 		/* Setting to IO mode */
851 		config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
852 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
853 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
854 		xqspi->mode = GQSPI_MODE_IO;
855 		xqspi->dma_rx_bytes = 0;
856 		return 0;
857 	}
858 
859 	rx_rem = xqspi->bytes_to_receive % 4;
860 	rx_bytes = (xqspi->bytes_to_receive - rx_rem);
861 
862 	addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
863 			      rx_bytes, DMA_FROM_DEVICE);
864 	if (dma_mapping_error(xqspi->dev, addr)) {
865 		dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
866 		return -ENOMEM;
867 	}
868 
869 	xqspi->dma_rx_bytes = rx_bytes;
870 	xqspi->dma_addr = addr;
871 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
872 			   (u32)(addr & 0xffffffff));
873 	addr = ((addr >> 16) >> 16);
874 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
875 			   ((u32)addr) & 0xfff);
876 
877 	/* Enabling the DMA mode */
878 	config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
879 	config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
880 	config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
881 	zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
882 
883 	/* Switch to DMA mode */
884 	xqspi->mode = GQSPI_MODE_DMA;
885 
886 	/* Write the number of bytes to transfer */
887 	zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
888 
889 	return 0;
890 }
891 
892 /**
893  * zynqmp_qspi_write_op - This function sets up the GENFIFO entries,
894  *			TX FIFO, and fills the TX FIFO with as many
895  *			bytes as possible.
896  * @xqspi:	Pointer to the GQSPI instance.
897  * @tx_nbits:	Transfer buswidth.
898  * @genfifoentry:	Variable in which GENFIFO mask is returned
899  *			to calling function
900  */
zynqmp_qspi_write_op(struct zynqmp_qspi * xqspi,u8 tx_nbits,u32 genfifoentry)901 static void zynqmp_qspi_write_op(struct zynqmp_qspi *xqspi, u8 tx_nbits,
902 				 u32 genfifoentry)
903 {
904 	u32 config_reg;
905 
906 	zynqmp_qspi_fillgenfifo(xqspi, tx_nbits, genfifoentry);
907 	zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
908 	if (xqspi->mode == GQSPI_MODE_DMA) {
909 		config_reg = zynqmp_gqspi_read(xqspi,
910 					       GQSPI_CONFIG_OFST);
911 		config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
912 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
913 				   config_reg);
914 		xqspi->mode = GQSPI_MODE_IO;
915 	}
916 }
917 
918 /**
919  * zynqmp_qspi_read_op - This function sets up the GENFIFO entries and
920  *				RX DMA operation.
921  * @xqspi:	xqspi is a pointer to the GQSPI instance.
922  * @rx_nbits:	Receive buswidth.
923  * @genfifoentry:	genfifoentry is pointer to the variable in which
924  *			GENFIFO	mask is returned to calling function
925  *
926  * Return:	0 on success; error value otherwise.
927  */
zynqmp_qspi_read_op(struct zynqmp_qspi * xqspi,u8 rx_nbits,u32 genfifoentry)928 static int zynqmp_qspi_read_op(struct zynqmp_qspi *xqspi, u8 rx_nbits,
929 				u32 genfifoentry)
930 {
931 	int ret;
932 
933 	ret = zynqmp_qspi_setuprxdma(xqspi);
934 	if (ret)
935 		return ret;
936 	zynqmp_qspi_fillgenfifo(xqspi, rx_nbits, genfifoentry);
937 
938 	return 0;
939 }
940 
941 /**
942  * zynqmp_qspi_suspend - Suspend method for the QSPI driver
943  * @dev:	Address of the platform_device structure
944  *
945  * This function stops the QSPI driver queue and disables the QSPI controller
946  *
947  * Return:	Always 0
948  */
zynqmp_qspi_suspend(struct device * dev)949 static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
950 {
951 	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
952 	struct spi_controller *ctlr = xqspi->ctlr;
953 	int ret;
954 
955 	ret = spi_controller_suspend(ctlr);
956 	if (ret)
957 		return ret;
958 
959 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
960 
961 	return 0;
962 }
963 
964 /**
965  * zynqmp_qspi_resume - Resume method for the QSPI driver
966  * @dev:	Address of the platform_device structure
967  *
968  * The function starts the QSPI driver queue and initializes the QSPI
969  * controller
970  *
971  * Return:	0 on success; error value otherwise
972  */
zynqmp_qspi_resume(struct device * dev)973 static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
974 {
975 	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
976 	struct spi_controller *ctlr = xqspi->ctlr;
977 
978 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
979 
980 	spi_controller_resume(ctlr);
981 
982 	return 0;
983 }
984 
985 /**
986  * zynqmp_runtime_suspend - Runtime suspend method for the SPI driver
987  * @dev:	Address of the platform_device structure
988  *
989  * This function disables the clocks
990  *
991  * Return:	Always 0
992  */
zynqmp_runtime_suspend(struct device * dev)993 static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
994 {
995 	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
996 
997 	clk_disable_unprepare(xqspi->refclk);
998 	clk_disable_unprepare(xqspi->pclk);
999 
1000 	return 0;
1001 }
1002 
1003 /**
1004  * zynqmp_runtime_resume - Runtime resume method for the SPI driver
1005  * @dev:	Address of the platform_device structure
1006  *
1007  * This function enables the clocks
1008  *
1009  * Return:	0 on success and error value on error
1010  */
zynqmp_runtime_resume(struct device * dev)1011 static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
1012 {
1013 	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
1014 	int ret;
1015 
1016 	ret = clk_prepare_enable(xqspi->pclk);
1017 	if (ret) {
1018 		dev_err(dev, "Cannot enable APB clock.\n");
1019 		return ret;
1020 	}
1021 
1022 	ret = clk_prepare_enable(xqspi->refclk);
1023 	if (ret) {
1024 		dev_err(dev, "Cannot enable device clock.\n");
1025 		clk_disable_unprepare(xqspi->pclk);
1026 		return ret;
1027 	}
1028 
1029 	return 0;
1030 }
1031 
1032 /**
1033  * zynqmp_qspi_exec_op() - Initiates the QSPI transfer
1034  * @mem: The SPI memory
1035  * @op: The memory operation to execute
1036  *
1037  * Executes a memory operation.
1038  *
1039  * This function first selects the chip and starts the memory operation.
1040  *
1041  * Return: 0 in case of success, a negative error code otherwise.
1042  */
zynqmp_qspi_exec_op(struct spi_mem * mem,const struct spi_mem_op * op)1043 static int zynqmp_qspi_exec_op(struct spi_mem *mem,
1044 			       const struct spi_mem_op *op)
1045 {
1046 	struct zynqmp_qspi *xqspi = spi_controller_get_devdata
1047 				    (mem->spi->master);
1048 	int err = 0, i;
1049 	u32 genfifoentry = 0;
1050 	u16 opcode = op->cmd.opcode;
1051 	u64 opaddr;
1052 
1053 	dev_dbg(xqspi->dev, "cmd:%#x mode:%d.%d.%d.%d\n",
1054 		op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth,
1055 		op->dummy.buswidth, op->data.buswidth);
1056 
1057 	mutex_lock(&xqspi->op_lock);
1058 	zynqmp_qspi_config_op(xqspi, mem->spi);
1059 	zynqmp_qspi_chipselect(mem->spi, false);
1060 	genfifoentry |= xqspi->genfifocs;
1061 	genfifoentry |= xqspi->genfifobus;
1062 
1063 	if (op->cmd.opcode) {
1064 		reinit_completion(&xqspi->data_completion);
1065 		xqspi->txbuf = &opcode;
1066 		xqspi->rxbuf = NULL;
1067 		xqspi->bytes_to_transfer = op->cmd.nbytes;
1068 		xqspi->bytes_to_receive = 0;
1069 		zynqmp_qspi_write_op(xqspi, op->cmd.buswidth, genfifoentry);
1070 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
1071 				   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
1072 				   GQSPI_CFG_START_GEN_FIFO_MASK);
1073 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
1074 				   GQSPI_IER_GENFIFOEMPTY_MASK |
1075 				   GQSPI_IER_TXNOT_FULL_MASK);
1076 		if (!wait_for_completion_timeout
1077 		    (&xqspi->data_completion, msecs_to_jiffies(1000))) {
1078 			err = -ETIMEDOUT;
1079 			goto return_err;
1080 		}
1081 	}
1082 
1083 	if (op->addr.nbytes) {
1084 		xqspi->txbuf = &opaddr;
1085 		for (i = 0; i < op->addr.nbytes; i++) {
1086 			*(((u8 *)xqspi->txbuf) + i) = op->addr.val >>
1087 					(8 * (op->addr.nbytes - i - 1));
1088 		}
1089 
1090 		reinit_completion(&xqspi->data_completion);
1091 		xqspi->rxbuf = NULL;
1092 		xqspi->bytes_to_transfer = op->addr.nbytes;
1093 		xqspi->bytes_to_receive = 0;
1094 		zynqmp_qspi_write_op(xqspi, op->addr.buswidth, genfifoentry);
1095 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
1096 				   zynqmp_gqspi_read(xqspi,
1097 						     GQSPI_CONFIG_OFST) |
1098 				   GQSPI_CFG_START_GEN_FIFO_MASK);
1099 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
1100 				   GQSPI_IER_TXEMPTY_MASK |
1101 				   GQSPI_IER_GENFIFOEMPTY_MASK |
1102 				   GQSPI_IER_TXNOT_FULL_MASK);
1103 		if (!wait_for_completion_timeout
1104 		    (&xqspi->data_completion, msecs_to_jiffies(1000))) {
1105 			err = -ETIMEDOUT;
1106 			goto return_err;
1107 		}
1108 	}
1109 
1110 	if (op->dummy.nbytes) {
1111 		xqspi->txbuf = NULL;
1112 		xqspi->rxbuf = NULL;
1113 		/*
1114 		 * xqspi->bytes_to_transfer here represents the dummy circles
1115 		 * which need to be sent.
1116 		 */
1117 		xqspi->bytes_to_transfer = op->dummy.nbytes * 8 / op->dummy.buswidth;
1118 		xqspi->bytes_to_receive = 0;
1119 		/*
1120 		 * Using op->data.buswidth instead of op->dummy.buswidth here because
1121 		 * we need to use it to configure the correct SPI mode.
1122 		 */
1123 		zynqmp_qspi_write_op(xqspi, op->data.buswidth,
1124 				     genfifoentry);
1125 		zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
1126 				   zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
1127 				   GQSPI_CFG_START_GEN_FIFO_MASK);
1128 	}
1129 
1130 	if (op->data.nbytes) {
1131 		reinit_completion(&xqspi->data_completion);
1132 		if (op->data.dir == SPI_MEM_DATA_OUT) {
1133 			xqspi->txbuf = (u8 *)op->data.buf.out;
1134 			xqspi->rxbuf = NULL;
1135 			xqspi->bytes_to_transfer = op->data.nbytes;
1136 			xqspi->bytes_to_receive = 0;
1137 			zynqmp_qspi_write_op(xqspi, op->data.buswidth,
1138 					     genfifoentry);
1139 			zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
1140 					   zynqmp_gqspi_read
1141 					   (xqspi, GQSPI_CONFIG_OFST) |
1142 					   GQSPI_CFG_START_GEN_FIFO_MASK);
1143 			zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
1144 					   GQSPI_IER_TXEMPTY_MASK |
1145 					   GQSPI_IER_GENFIFOEMPTY_MASK |
1146 					   GQSPI_IER_TXNOT_FULL_MASK);
1147 		} else {
1148 			xqspi->txbuf = NULL;
1149 			xqspi->rxbuf = (u8 *)op->data.buf.in;
1150 			xqspi->bytes_to_receive = op->data.nbytes;
1151 			xqspi->bytes_to_transfer = 0;
1152 			err = zynqmp_qspi_read_op(xqspi, op->data.buswidth,
1153 					    genfifoentry);
1154 			if (err)
1155 				goto return_err;
1156 
1157 			zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
1158 					   zynqmp_gqspi_read
1159 					   (xqspi, GQSPI_CONFIG_OFST) |
1160 					   GQSPI_CFG_START_GEN_FIFO_MASK);
1161 			if (xqspi->mode == GQSPI_MODE_DMA) {
1162 				zynqmp_gqspi_write
1163 					(xqspi, GQSPI_QSPIDMA_DST_I_EN_OFST,
1164 					 GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
1165 			} else {
1166 				zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
1167 						   GQSPI_IER_GENFIFOEMPTY_MASK |
1168 						   GQSPI_IER_RXNEMPTY_MASK |
1169 						   GQSPI_IER_RXEMPTY_MASK);
1170 			}
1171 		}
1172 		if (!wait_for_completion_timeout
1173 		    (&xqspi->data_completion, msecs_to_jiffies(1000)))
1174 			err = -ETIMEDOUT;
1175 	}
1176 
1177 return_err:
1178 
1179 	zynqmp_qspi_chipselect(mem->spi, true);
1180 	mutex_unlock(&xqspi->op_lock);
1181 
1182 	return err;
1183 }
1184 
1185 static const struct dev_pm_ops zynqmp_qspi_dev_pm_ops = {
1186 	SET_RUNTIME_PM_OPS(zynqmp_runtime_suspend,
1187 			   zynqmp_runtime_resume, NULL)
1188 	SET_SYSTEM_SLEEP_PM_OPS(zynqmp_qspi_suspend, zynqmp_qspi_resume)
1189 };
1190 
1191 static const struct qspi_platform_data versal_qspi_def = {
1192 	.quirks = QSPI_QUIRK_HAS_TAPDELAY,
1193 };
1194 
1195 static const struct of_device_id zynqmp_qspi_of_match[] = {
1196 	{ .compatible = "xlnx,zynqmp-qspi-1.0"},
1197 	{ .compatible = "xlnx,versal-qspi-1.0", .data = &versal_qspi_def },
1198 	{ /* End of table */ }
1199 };
1200 
1201 static const struct spi_controller_mem_ops zynqmp_qspi_mem_ops = {
1202 	.exec_op = zynqmp_qspi_exec_op,
1203 };
1204 
1205 /**
1206  * zynqmp_qspi_probe - Probe method for the QSPI driver
1207  * @pdev:	Pointer to the platform_device structure
1208  *
1209  * This function initializes the driver data structures and the hardware.
1210  *
1211  * Return:	0 on success; error value otherwise
1212  */
zynqmp_qspi_probe(struct platform_device * pdev)1213 static int zynqmp_qspi_probe(struct platform_device *pdev)
1214 {
1215 	int ret = 0;
1216 	struct spi_controller *ctlr;
1217 	struct zynqmp_qspi *xqspi;
1218 	struct device *dev = &pdev->dev;
1219 	struct device_node *np = dev->of_node;
1220 	u32 num_cs;
1221 	const struct qspi_platform_data *p_data;
1222 
1223 	ctlr = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
1224 	if (!ctlr)
1225 		return -ENOMEM;
1226 
1227 	xqspi = spi_controller_get_devdata(ctlr);
1228 	xqspi->dev = dev;
1229 	xqspi->ctlr = ctlr;
1230 	platform_set_drvdata(pdev, xqspi);
1231 
1232 	p_data = of_device_get_match_data(&pdev->dev);
1233 	if (p_data && (p_data->quirks & QSPI_QUIRK_HAS_TAPDELAY))
1234 		xqspi->has_tapdelay = true;
1235 
1236 	xqspi->regs = devm_platform_ioremap_resource(pdev, 0);
1237 	if (IS_ERR(xqspi->regs)) {
1238 		ret = PTR_ERR(xqspi->regs);
1239 		goto remove_master;
1240 	}
1241 
1242 	xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
1243 	if (IS_ERR(xqspi->pclk)) {
1244 		dev_err(dev, "pclk clock not found.\n");
1245 		ret = PTR_ERR(xqspi->pclk);
1246 		goto remove_master;
1247 	}
1248 
1249 	xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
1250 	if (IS_ERR(xqspi->refclk)) {
1251 		dev_err(dev, "ref_clk clock not found.\n");
1252 		ret = PTR_ERR(xqspi->refclk);
1253 		goto remove_master;
1254 	}
1255 
1256 	ret = clk_prepare_enable(xqspi->pclk);
1257 	if (ret) {
1258 		dev_err(dev, "Unable to enable APB clock.\n");
1259 		goto remove_master;
1260 	}
1261 
1262 	ret = clk_prepare_enable(xqspi->refclk);
1263 	if (ret) {
1264 		dev_err(dev, "Unable to enable device clock.\n");
1265 		goto clk_dis_pclk;
1266 	}
1267 
1268 	init_completion(&xqspi->data_completion);
1269 
1270 	mutex_init(&xqspi->op_lock);
1271 
1272 	pm_runtime_use_autosuspend(&pdev->dev);
1273 	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1274 	pm_runtime_set_active(&pdev->dev);
1275 	pm_runtime_enable(&pdev->dev);
1276 
1277 	ret = pm_runtime_get_sync(&pdev->dev);
1278 	if (ret < 0) {
1279 		dev_err(&pdev->dev, "Failed to pm_runtime_get_sync: %d\n", ret);
1280 		goto clk_dis_all;
1281 	}
1282 
1283 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
1284 		SPI_TX_DUAL | SPI_TX_QUAD;
1285 	ctlr->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
1286 	xqspi->speed_hz = ctlr->max_speed_hz;
1287 
1288 	/* QSPI controller initializations */
1289 	zynqmp_qspi_init_hw(xqspi);
1290 
1291 	xqspi->irq = platform_get_irq(pdev, 0);
1292 	if (xqspi->irq < 0) {
1293 		ret = xqspi->irq;
1294 		goto clk_dis_all;
1295 	}
1296 	ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
1297 			       0, pdev->name, xqspi);
1298 	if (ret != 0) {
1299 		ret = -ENXIO;
1300 		dev_err(dev, "request_irq failed\n");
1301 		goto clk_dis_all;
1302 	}
1303 
1304 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(44));
1305 	if (ret)
1306 		goto clk_dis_all;
1307 
1308 	ret = of_property_read_u32(np, "num-cs", &num_cs);
1309 	if (ret < 0) {
1310 		ctlr->num_chipselect = GQSPI_DEFAULT_NUM_CS;
1311 	} else if (num_cs > GQSPI_MAX_NUM_CS) {
1312 		ret = -EINVAL;
1313 		dev_err(&pdev->dev, "only %d chip selects are available\n",
1314 			GQSPI_MAX_NUM_CS);
1315 		goto clk_dis_all;
1316 	} else {
1317 		ctlr->num_chipselect = num_cs;
1318 	}
1319 
1320 	ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
1321 	ctlr->mem_ops = &zynqmp_qspi_mem_ops;
1322 	ctlr->setup = zynqmp_qspi_setup_op;
1323 	ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
1324 	ctlr->dev.of_node = np;
1325 	ctlr->auto_runtime_pm = true;
1326 
1327 	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1328 	if (ret) {
1329 		dev_err(&pdev->dev, "spi_register_controller failed\n");
1330 		goto clk_dis_all;
1331 	}
1332 
1333 	pm_runtime_mark_last_busy(&pdev->dev);
1334 	pm_runtime_put_autosuspend(&pdev->dev);
1335 
1336 	return 0;
1337 
1338 clk_dis_all:
1339 	pm_runtime_disable(&pdev->dev);
1340 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1341 	pm_runtime_put_noidle(&pdev->dev);
1342 	pm_runtime_set_suspended(&pdev->dev);
1343 	clk_disable_unprepare(xqspi->refclk);
1344 clk_dis_pclk:
1345 	clk_disable_unprepare(xqspi->pclk);
1346 remove_master:
1347 	spi_controller_put(ctlr);
1348 
1349 	return ret;
1350 }
1351 
1352 /**
1353  * zynqmp_qspi_remove - Remove method for the QSPI driver
1354  * @pdev:	Pointer to the platform_device structure
1355  *
1356  * This function is called if a device is physically removed from the system or
1357  * if the driver module is being unloaded. It frees all resources allocated to
1358  * the device.
1359  *
1360  * Return:	0 Always
1361  */
zynqmp_qspi_remove(struct platform_device * pdev)1362 static void zynqmp_qspi_remove(struct platform_device *pdev)
1363 {
1364 	struct zynqmp_qspi *xqspi = platform_get_drvdata(pdev);
1365 
1366 	pm_runtime_get_sync(&pdev->dev);
1367 
1368 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
1369 
1370 	pm_runtime_disable(&pdev->dev);
1371 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1372 	pm_runtime_put_noidle(&pdev->dev);
1373 	pm_runtime_set_suspended(&pdev->dev);
1374 	clk_disable_unprepare(xqspi->refclk);
1375 	clk_disable_unprepare(xqspi->pclk);
1376 }
1377 
1378 MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
1379 
1380 static struct platform_driver zynqmp_qspi_driver = {
1381 	.probe = zynqmp_qspi_probe,
1382 	.remove_new = zynqmp_qspi_remove,
1383 	.driver = {
1384 		.name = "zynqmp-qspi",
1385 		.of_match_table = zynqmp_qspi_of_match,
1386 		.pm = &zynqmp_qspi_dev_pm_ops,
1387 	},
1388 };
1389 
1390 module_platform_driver(zynqmp_qspi_driver);
1391 
1392 MODULE_AUTHOR("Xilinx, Inc.");
1393 MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
1394 MODULE_LICENSE("GPL");
1395