xref: /openbmc/linux/drivers/spi/spi-nxp-fspi.c (revision ae213c44)
1 // SPDX-License-Identifier: GPL-2.0+
2 
3 /*
4  * NXP FlexSPI(FSPI) controller driver.
5  *
6  * Copyright 2019 NXP.
7  *
8  * FlexSPI is a flexsible SPI host controller which supports two SPI
9  * channels and up to 4 external devices. Each channel supports
10  * Single/Dual/Quad/Octal mode data transfer (1/2/4/8 bidirectional
11  * data lines).
12  *
13  * FlexSPI controller is driven by the LUT(Look-up Table) registers
14  * LUT registers are a look-up-table for sequences of instructions.
15  * A valid sequence consists of four LUT registers.
16  * Maximum 32 LUT sequences can be programmed simultaneously.
17  *
18  * LUTs are being created at run-time based on the commands passed
19  * from the spi-mem framework, thus using single LUT index.
20  *
21  * Software triggered Flash read/write access by IP Bus.
22  *
23  * Memory mapped read access by AHB Bus.
24  *
25  * Based on SPI MEM interface and spi-fsl-qspi.c driver.
26  *
27  * Author:
28  *     Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>
29  *     Boris Brezillon <bbrezillon@kernel.org>
30  *     Frieder Schrempf <frieder.schrempf@kontron.de>
31  */
32 
33 #include <linux/bitops.h>
34 #include <linux/clk.h>
35 #include <linux/completion.h>
36 #include <linux/delay.h>
37 #include <linux/err.h>
38 #include <linux/errno.h>
39 #include <linux/interrupt.h>
40 #include <linux/io.h>
41 #include <linux/iopoll.h>
42 #include <linux/jiffies.h>
43 #include <linux/kernel.h>
44 #include <linux/module.h>
45 #include <linux/mutex.h>
46 #include <linux/of.h>
47 #include <linux/of_device.h>
48 #include <linux/platform_device.h>
49 #include <linux/pm_qos.h>
50 #include <linux/sizes.h>
51 
52 #include <linux/spi/spi.h>
53 #include <linux/spi/spi-mem.h>
54 
55 /*
56  * The driver only uses one single LUT entry, that is updated on
57  * each call of exec_op(). Index 0 is preset at boot with a basic
58  * read operation, so let's use the last entry (31).
59  */
60 #define	SEQID_LUT			31
61 
62 /* Registers used by the driver */
63 #define FSPI_MCR0			0x00
64 #define FSPI_MCR0_AHB_TIMEOUT(x)	((x) << 24)
65 #define FSPI_MCR0_IP_TIMEOUT(x)		((x) << 16)
66 #define FSPI_MCR0_LEARN_EN		BIT(15)
67 #define FSPI_MCR0_SCRFRUN_EN		BIT(14)
68 #define FSPI_MCR0_OCTCOMB_EN		BIT(13)
69 #define FSPI_MCR0_DOZE_EN		BIT(12)
70 #define FSPI_MCR0_HSEN			BIT(11)
71 #define FSPI_MCR0_SERCLKDIV		BIT(8)
72 #define FSPI_MCR0_ATDF_EN		BIT(7)
73 #define FSPI_MCR0_ARDF_EN		BIT(6)
74 #define FSPI_MCR0_RXCLKSRC(x)		((x) << 4)
75 #define FSPI_MCR0_END_CFG(x)		((x) << 2)
76 #define FSPI_MCR0_MDIS			BIT(1)
77 #define FSPI_MCR0_SWRST			BIT(0)
78 
79 #define FSPI_MCR1			0x04
80 #define FSPI_MCR1_SEQ_TIMEOUT(x)	((x) << 16)
81 #define FSPI_MCR1_AHB_TIMEOUT(x)	(x)
82 
83 #define FSPI_MCR2			0x08
84 #define FSPI_MCR2_IDLE_WAIT(x)		((x) << 24)
85 #define FSPI_MCR2_SAMEDEVICEEN		BIT(15)
86 #define FSPI_MCR2_CLRLRPHS		BIT(14)
87 #define FSPI_MCR2_ABRDATSZ		BIT(8)
88 #define FSPI_MCR2_ABRLEARN		BIT(7)
89 #define FSPI_MCR2_ABR_READ		BIT(6)
90 #define FSPI_MCR2_ABRWRITE		BIT(5)
91 #define FSPI_MCR2_ABRDUMMY		BIT(4)
92 #define FSPI_MCR2_ABR_MODE		BIT(3)
93 #define FSPI_MCR2_ABRCADDR		BIT(2)
94 #define FSPI_MCR2_ABRRADDR		BIT(1)
95 #define FSPI_MCR2_ABR_CMD		BIT(0)
96 
97 #define FSPI_AHBCR			0x0c
98 #define FSPI_AHBCR_RDADDROPT		BIT(6)
99 #define FSPI_AHBCR_PREF_EN		BIT(5)
100 #define FSPI_AHBCR_BUFF_EN		BIT(4)
101 #define FSPI_AHBCR_CACH_EN		BIT(3)
102 #define FSPI_AHBCR_CLRTXBUF		BIT(2)
103 #define FSPI_AHBCR_CLRRXBUF		BIT(1)
104 #define FSPI_AHBCR_PAR_EN		BIT(0)
105 
106 #define FSPI_INTEN			0x10
107 #define FSPI_INTEN_SCLKSBWR		BIT(9)
108 #define FSPI_INTEN_SCLKSBRD		BIT(8)
109 #define FSPI_INTEN_DATALRNFL		BIT(7)
110 #define FSPI_INTEN_IPTXWE		BIT(6)
111 #define FSPI_INTEN_IPRXWA		BIT(5)
112 #define FSPI_INTEN_AHBCMDERR		BIT(4)
113 #define FSPI_INTEN_IPCMDERR		BIT(3)
114 #define FSPI_INTEN_AHBCMDGE		BIT(2)
115 #define FSPI_INTEN_IPCMDGE		BIT(1)
116 #define FSPI_INTEN_IPCMDDONE		BIT(0)
117 
118 #define FSPI_INTR			0x14
119 #define FSPI_INTR_SCLKSBWR		BIT(9)
120 #define FSPI_INTR_SCLKSBRD		BIT(8)
121 #define FSPI_INTR_DATALRNFL		BIT(7)
122 #define FSPI_INTR_IPTXWE		BIT(6)
123 #define FSPI_INTR_IPRXWA		BIT(5)
124 #define FSPI_INTR_AHBCMDERR		BIT(4)
125 #define FSPI_INTR_IPCMDERR		BIT(3)
126 #define FSPI_INTR_AHBCMDGE		BIT(2)
127 #define FSPI_INTR_IPCMDGE		BIT(1)
128 #define FSPI_INTR_IPCMDDONE		BIT(0)
129 
130 #define FSPI_LUTKEY			0x18
131 #define FSPI_LUTKEY_VALUE		0x5AF05AF0
132 
133 #define FSPI_LCKCR			0x1C
134 
135 #define FSPI_LCKER_LOCK			0x1
136 #define FSPI_LCKER_UNLOCK		0x2
137 
138 #define FSPI_BUFXCR_INVALID_MSTRID	0xE
139 #define FSPI_AHBRX_BUF0CR0		0x20
140 #define FSPI_AHBRX_BUF1CR0		0x24
141 #define FSPI_AHBRX_BUF2CR0		0x28
142 #define FSPI_AHBRX_BUF3CR0		0x2C
143 #define FSPI_AHBRX_BUF4CR0		0x30
144 #define FSPI_AHBRX_BUF5CR0		0x34
145 #define FSPI_AHBRX_BUF6CR0		0x38
146 #define FSPI_AHBRX_BUF7CR0		0x3C
147 #define FSPI_AHBRXBUF0CR7_PREF		BIT(31)
148 
149 #define FSPI_AHBRX_BUF0CR1		0x40
150 #define FSPI_AHBRX_BUF1CR1		0x44
151 #define FSPI_AHBRX_BUF2CR1		0x48
152 #define FSPI_AHBRX_BUF3CR1		0x4C
153 #define FSPI_AHBRX_BUF4CR1		0x50
154 #define FSPI_AHBRX_BUF5CR1		0x54
155 #define FSPI_AHBRX_BUF6CR1		0x58
156 #define FSPI_AHBRX_BUF7CR1		0x5C
157 
158 #define FSPI_FLSHA1CR0			0x60
159 #define FSPI_FLSHA2CR0			0x64
160 #define FSPI_FLSHB1CR0			0x68
161 #define FSPI_FLSHB2CR0			0x6C
162 #define FSPI_FLSHXCR0_SZ_KB		10
163 #define FSPI_FLSHXCR0_SZ(x)		((x) >> FSPI_FLSHXCR0_SZ_KB)
164 
165 #define FSPI_FLSHA1CR1			0x70
166 #define FSPI_FLSHA2CR1			0x74
167 #define FSPI_FLSHB1CR1			0x78
168 #define FSPI_FLSHB2CR1			0x7C
169 #define FSPI_FLSHXCR1_CSINTR(x)		((x) << 16)
170 #define FSPI_FLSHXCR1_CAS(x)		((x) << 11)
171 #define FSPI_FLSHXCR1_WA		BIT(10)
172 #define FSPI_FLSHXCR1_TCSH(x)		((x) << 5)
173 #define FSPI_FLSHXCR1_TCSS(x)		(x)
174 
175 #define FSPI_FLSHA1CR2			0x80
176 #define FSPI_FLSHA2CR2			0x84
177 #define FSPI_FLSHB1CR2			0x88
178 #define FSPI_FLSHB2CR2			0x8C
179 #define FSPI_FLSHXCR2_CLRINSP		BIT(24)
180 #define FSPI_FLSHXCR2_AWRWAIT		BIT(16)
181 #define FSPI_FLSHXCR2_AWRSEQN_SHIFT	13
182 #define FSPI_FLSHXCR2_AWRSEQI_SHIFT	8
183 #define FSPI_FLSHXCR2_ARDSEQN_SHIFT	5
184 #define FSPI_FLSHXCR2_ARDSEQI_SHIFT	0
185 
186 #define FSPI_IPCR0			0xA0
187 
188 #define FSPI_IPCR1			0xA4
189 #define FSPI_IPCR1_IPAREN		BIT(31)
190 #define FSPI_IPCR1_SEQNUM_SHIFT		24
191 #define FSPI_IPCR1_SEQID_SHIFT		16
192 #define FSPI_IPCR1_IDATSZ(x)		(x)
193 
194 #define FSPI_IPCMD			0xB0
195 #define FSPI_IPCMD_TRG			BIT(0)
196 
197 #define FSPI_DLPR			0xB4
198 
199 #define FSPI_IPRXFCR			0xB8
200 #define FSPI_IPRXFCR_CLR		BIT(0)
201 #define FSPI_IPRXFCR_DMA_EN		BIT(1)
202 #define FSPI_IPRXFCR_WMRK(x)		((x) << 2)
203 
204 #define FSPI_IPTXFCR			0xBC
205 #define FSPI_IPTXFCR_CLR		BIT(0)
206 #define FSPI_IPTXFCR_DMA_EN		BIT(1)
207 #define FSPI_IPTXFCR_WMRK(x)		((x) << 2)
208 
209 #define FSPI_DLLACR			0xC0
210 #define FSPI_DLLACR_OVRDEN		BIT(8)
211 
212 #define FSPI_DLLBCR			0xC4
213 #define FSPI_DLLBCR_OVRDEN		BIT(8)
214 
215 #define FSPI_STS0			0xE0
216 #define FSPI_STS0_DLPHB(x)		((x) << 8)
217 #define FSPI_STS0_DLPHA(x)		((x) << 4)
218 #define FSPI_STS0_CMD_SRC(x)		((x) << 2)
219 #define FSPI_STS0_ARB_IDLE		BIT(1)
220 #define FSPI_STS0_SEQ_IDLE		BIT(0)
221 
222 #define FSPI_STS1			0xE4
223 #define FSPI_STS1_IP_ERRCD(x)		((x) << 24)
224 #define FSPI_STS1_IP_ERRID(x)		((x) << 16)
225 #define FSPI_STS1_AHB_ERRCD(x)		((x) << 8)
226 #define FSPI_STS1_AHB_ERRID(x)		(x)
227 
228 #define FSPI_AHBSPNST			0xEC
229 #define FSPI_AHBSPNST_DATLFT(x)		((x) << 16)
230 #define FSPI_AHBSPNST_BUFID(x)		((x) << 1)
231 #define FSPI_AHBSPNST_ACTIVE		BIT(0)
232 
233 #define FSPI_IPRXFSTS			0xF0
234 #define FSPI_IPRXFSTS_RDCNTR(x)		((x) << 16)
235 #define FSPI_IPRXFSTS_FILL(x)		(x)
236 
237 #define FSPI_IPTXFSTS			0xF4
238 #define FSPI_IPTXFSTS_WRCNTR(x)		((x) << 16)
239 #define FSPI_IPTXFSTS_FILL(x)		(x)
240 
241 #define FSPI_RFDR			0x100
242 #define FSPI_TFDR			0x180
243 
244 #define FSPI_LUT_BASE			0x200
245 #define FSPI_LUT_OFFSET			(SEQID_LUT * 4 * 4)
246 #define FSPI_LUT_REG(idx) \
247 	(FSPI_LUT_BASE + FSPI_LUT_OFFSET + (idx) * 4)
248 
249 /* register map end */
250 
251 /* Instruction set for the LUT register. */
252 #define LUT_STOP			0x00
253 #define LUT_CMD				0x01
254 #define LUT_ADDR			0x02
255 #define LUT_CADDR_SDR			0x03
256 #define LUT_MODE			0x04
257 #define LUT_MODE2			0x05
258 #define LUT_MODE4			0x06
259 #define LUT_MODE8			0x07
260 #define LUT_NXP_WRITE			0x08
261 #define LUT_NXP_READ			0x09
262 #define LUT_LEARN_SDR			0x0A
263 #define LUT_DATSZ_SDR			0x0B
264 #define LUT_DUMMY			0x0C
265 #define LUT_DUMMY_RWDS_SDR		0x0D
266 #define LUT_JMP_ON_CS			0x1F
267 #define LUT_CMD_DDR			0x21
268 #define LUT_ADDR_DDR			0x22
269 #define LUT_CADDR_DDR			0x23
270 #define LUT_MODE_DDR			0x24
271 #define LUT_MODE2_DDR			0x25
272 #define LUT_MODE4_DDR			0x26
273 #define LUT_MODE8_DDR			0x27
274 #define LUT_WRITE_DDR			0x28
275 #define LUT_READ_DDR			0x29
276 #define LUT_LEARN_DDR			0x2A
277 #define LUT_DATSZ_DDR			0x2B
278 #define LUT_DUMMY_DDR			0x2C
279 #define LUT_DUMMY_RWDS_DDR		0x2D
280 
281 /*
282  * Calculate number of required PAD bits for LUT register.
283  *
284  * The pad stands for the number of IO lines [0:7].
285  * For example, the octal read needs eight IO lines,
286  * so you should use LUT_PAD(8). This macro
287  * returns 3 i.e. use eight (2^3) IP lines for read.
288  */
289 #define LUT_PAD(x) (fls(x) - 1)
290 
291 /*
292  * Macro for constructing the LUT entries with the following
293  * register layout:
294  *
295  *  ---------------------------------------------------
296  *  | INSTR1 | PAD1 | OPRND1 | INSTR0 | PAD0 | OPRND0 |
297  *  ---------------------------------------------------
298  */
299 #define PAD_SHIFT		8
300 #define INSTR_SHIFT		10
301 #define OPRND_SHIFT		16
302 
303 /* Macros for constructing the LUT register. */
304 #define LUT_DEF(idx, ins, pad, opr)			  \
305 	((((ins) << INSTR_SHIFT) | ((pad) << PAD_SHIFT) | \
306 	(opr)) << (((idx) % 2) * OPRND_SHIFT))
307 
308 #define POLL_TOUT		5000
309 #define NXP_FSPI_MAX_CHIPSELECT		4
310 
311 struct nxp_fspi_devtype_data {
312 	unsigned int rxfifo;
313 	unsigned int txfifo;
314 	unsigned int ahb_buf_size;
315 	unsigned int quirks;
316 	bool little_endian;
317 };
318 
319 static const struct nxp_fspi_devtype_data lx2160a_data = {
320 	.rxfifo = SZ_512,       /* (64  * 64 bits)  */
321 	.txfifo = SZ_1K,        /* (128 * 64 bits)  */
322 	.ahb_buf_size = SZ_2K,  /* (256 * 64 bits)  */
323 	.quirks = 0,
324 	.little_endian = true,  /* little-endian    */
325 };
326 
327 struct nxp_fspi {
328 	void __iomem *iobase;
329 	void __iomem *ahb_addr;
330 	u32 memmap_phy;
331 	u32 memmap_phy_size;
332 	struct clk *clk, *clk_en;
333 	struct device *dev;
334 	struct completion c;
335 	const struct nxp_fspi_devtype_data *devtype_data;
336 	struct mutex lock;
337 	struct pm_qos_request pm_qos_req;
338 	int selected;
339 };
340 
341 /*
342  * R/W functions for big- or little-endian registers:
343  * The FSPI controller's endianness is independent of
344  * the CPU core's endianness. So far, although the CPU
345  * core is little-endian the FSPI controller can use
346  * big-endian or little-endian.
347  */
348 static void fspi_writel(struct nxp_fspi *f, u32 val, void __iomem *addr)
349 {
350 	if (f->devtype_data->little_endian)
351 		iowrite32(val, addr);
352 	else
353 		iowrite32be(val, addr);
354 }
355 
356 static u32 fspi_readl(struct nxp_fspi *f, void __iomem *addr)
357 {
358 	if (f->devtype_data->little_endian)
359 		return ioread32(addr);
360 	else
361 		return ioread32be(addr);
362 }
363 
364 static irqreturn_t nxp_fspi_irq_handler(int irq, void *dev_id)
365 {
366 	struct nxp_fspi *f = dev_id;
367 	u32 reg;
368 
369 	/* clear interrupt */
370 	reg = fspi_readl(f, f->iobase + FSPI_INTR);
371 	fspi_writel(f, FSPI_INTR_IPCMDDONE, f->iobase + FSPI_INTR);
372 
373 	if (reg & FSPI_INTR_IPCMDDONE)
374 		complete(&f->c);
375 
376 	return IRQ_HANDLED;
377 }
378 
379 static int nxp_fspi_check_buswidth(struct nxp_fspi *f, u8 width)
380 {
381 	switch (width) {
382 	case 1:
383 	case 2:
384 	case 4:
385 	case 8:
386 		return 0;
387 	}
388 
389 	return -ENOTSUPP;
390 }
391 
392 static bool nxp_fspi_supports_op(struct spi_mem *mem,
393 				 const struct spi_mem_op *op)
394 {
395 	struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
396 	int ret;
397 
398 	ret = nxp_fspi_check_buswidth(f, op->cmd.buswidth);
399 
400 	if (op->addr.nbytes)
401 		ret |= nxp_fspi_check_buswidth(f, op->addr.buswidth);
402 
403 	if (op->dummy.nbytes)
404 		ret |= nxp_fspi_check_buswidth(f, op->dummy.buswidth);
405 
406 	if (op->data.nbytes)
407 		ret |= nxp_fspi_check_buswidth(f, op->data.buswidth);
408 
409 	if (ret)
410 		return false;
411 
412 	/*
413 	 * The number of address bytes should be equal to or less than 4 bytes.
414 	 */
415 	if (op->addr.nbytes > 4)
416 		return false;
417 
418 	/*
419 	 * If requested address value is greater than controller assigned
420 	 * memory mapped space, return error as it didn't fit in the range
421 	 * of assigned address space.
422 	 */
423 	if (op->addr.val >= f->memmap_phy_size)
424 		return false;
425 
426 	/* Max 64 dummy clock cycles supported */
427 	if (op->dummy.buswidth &&
428 	    (op->dummy.nbytes * 8 / op->dummy.buswidth > 64))
429 		return false;
430 
431 	/* Max data length, check controller limits and alignment */
432 	if (op->data.dir == SPI_MEM_DATA_IN &&
433 	    (op->data.nbytes > f->devtype_data->ahb_buf_size ||
434 	     (op->data.nbytes > f->devtype_data->rxfifo - 4 &&
435 	      !IS_ALIGNED(op->data.nbytes, 8))))
436 		return false;
437 
438 	if (op->data.dir == SPI_MEM_DATA_OUT &&
439 	    op->data.nbytes > f->devtype_data->txfifo)
440 		return false;
441 
442 	return true;
443 }
444 
445 /* Instead of busy looping invoke readl_poll_timeout functionality. */
446 static int fspi_readl_poll_tout(struct nxp_fspi *f, void __iomem *base,
447 				u32 mask, u32 delay_us,
448 				u32 timeout_us, bool c)
449 {
450 	u32 reg;
451 
452 	if (!f->devtype_data->little_endian)
453 		mask = (u32)cpu_to_be32(mask);
454 
455 	if (c)
456 		return readl_poll_timeout(base, reg, (reg & mask),
457 					  delay_us, timeout_us);
458 	else
459 		return readl_poll_timeout(base, reg, !(reg & mask),
460 					  delay_us, timeout_us);
461 }
462 
463 /*
464  * If the slave device content being changed by Write/Erase, need to
465  * invalidate the AHB buffer. This can be achieved by doing the reset
466  * of controller after setting MCR0[SWRESET] bit.
467  */
468 static inline void nxp_fspi_invalid(struct nxp_fspi *f)
469 {
470 	u32 reg;
471 	int ret;
472 
473 	reg = fspi_readl(f, f->iobase + FSPI_MCR0);
474 	fspi_writel(f, reg | FSPI_MCR0_SWRST, f->iobase + FSPI_MCR0);
475 
476 	/* w1c register, wait unit clear */
477 	ret = fspi_readl_poll_tout(f, f->iobase + FSPI_MCR0,
478 				   FSPI_MCR0_SWRST, 0, POLL_TOUT, false);
479 	WARN_ON(ret);
480 }
481 
482 static void nxp_fspi_prepare_lut(struct nxp_fspi *f,
483 				 const struct spi_mem_op *op)
484 {
485 	void __iomem *base = f->iobase;
486 	u32 lutval[4] = {};
487 	int lutidx = 1, i;
488 
489 	/* cmd */
490 	lutval[0] |= LUT_DEF(0, LUT_CMD, LUT_PAD(op->cmd.buswidth),
491 			     op->cmd.opcode);
492 
493 	/* addr bytes */
494 	if (op->addr.nbytes) {
495 		lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_ADDR,
496 					      LUT_PAD(op->addr.buswidth),
497 					      op->addr.nbytes * 8);
498 		lutidx++;
499 	}
500 
501 	/* dummy bytes, if needed */
502 	if (op->dummy.nbytes) {
503 		lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_DUMMY,
504 		/*
505 		 * Due to FlexSPI controller limitation number of PAD for dummy
506 		 * buswidth needs to be programmed as equal to data buswidth.
507 		 */
508 					      LUT_PAD(op->data.buswidth),
509 					      op->dummy.nbytes * 8 /
510 					      op->dummy.buswidth);
511 		lutidx++;
512 	}
513 
514 	/* read/write data bytes */
515 	if (op->data.nbytes) {
516 		lutval[lutidx / 2] |= LUT_DEF(lutidx,
517 					      op->data.dir == SPI_MEM_DATA_IN ?
518 					      LUT_NXP_READ : LUT_NXP_WRITE,
519 					      LUT_PAD(op->data.buswidth),
520 					      0);
521 		lutidx++;
522 	}
523 
524 	/* stop condition. */
525 	lutval[lutidx / 2] |= LUT_DEF(lutidx, LUT_STOP, 0, 0);
526 
527 	/* unlock LUT */
528 	fspi_writel(f, FSPI_LUTKEY_VALUE, f->iobase + FSPI_LUTKEY);
529 	fspi_writel(f, FSPI_LCKER_UNLOCK, f->iobase + FSPI_LCKCR);
530 
531 	/* fill LUT */
532 	for (i = 0; i < ARRAY_SIZE(lutval); i++)
533 		fspi_writel(f, lutval[i], base + FSPI_LUT_REG(i));
534 
535 	dev_dbg(f->dev, "CMD[%x] lutval[0:%x \t 1:%x \t 2:%x \t 3:%x]\n",
536 		op->cmd.opcode, lutval[0], lutval[1], lutval[2], lutval[3]);
537 
538 	/* lock LUT */
539 	fspi_writel(f, FSPI_LUTKEY_VALUE, f->iobase + FSPI_LUTKEY);
540 	fspi_writel(f, FSPI_LCKER_LOCK, f->iobase + FSPI_LCKCR);
541 }
542 
543 static int nxp_fspi_clk_prep_enable(struct nxp_fspi *f)
544 {
545 	int ret;
546 
547 	ret = clk_prepare_enable(f->clk_en);
548 	if (ret)
549 		return ret;
550 
551 	ret = clk_prepare_enable(f->clk);
552 	if (ret) {
553 		clk_disable_unprepare(f->clk_en);
554 		return ret;
555 	}
556 
557 	return 0;
558 }
559 
560 static void nxp_fspi_clk_disable_unprep(struct nxp_fspi *f)
561 {
562 	clk_disable_unprepare(f->clk);
563 	clk_disable_unprepare(f->clk_en);
564 }
565 
566 /*
567  * In FlexSPI controller, flash access is based on value of FSPI_FLSHXXCR0
568  * register and start base address of the slave device.
569  *
570  *							    (Higher address)
571  *				--------    <-- FLSHB2CR0
572  *				|  B2  |
573  *				|      |
574  *	B2 start address -->	--------    <-- FLSHB1CR0
575  *				|  B1  |
576  *				|      |
577  *	B1 start address -->	--------    <-- FLSHA2CR0
578  *				|  A2  |
579  *				|      |
580  *	A2 start address -->	--------    <-- FLSHA1CR0
581  *				|  A1  |
582  *				|      |
583  *	A1 start address -->	--------		    (Lower address)
584  *
585  *
586  * Start base address defines the starting address range for given CS and
587  * FSPI_FLSHXXCR0 defines the size of the slave device connected at given CS.
588  *
589  * But, different targets are having different combinations of number of CS,
590  * some targets only have single CS or two CS covering controller's full
591  * memory mapped space area.
592  * Thus, implementation is being done as independent of the size and number
593  * of the connected slave device.
594  * Assign controller memory mapped space size as the size to the connected
595  * slave device.
596  * Mark FLSHxxCR0 as zero initially and then assign value only to the selected
597  * chip-select Flash configuration register.
598  *
599  * For e.g. to access CS2 (B1), FLSHB1CR0 register would be equal to the
600  * memory mapped size of the controller.
601  * Value for rest of the CS FLSHxxCR0 register would be zero.
602  *
603  */
604 static void nxp_fspi_select_mem(struct nxp_fspi *f, struct spi_device *spi)
605 {
606 	unsigned long rate = spi->max_speed_hz;
607 	int ret;
608 	uint64_t size_kb;
609 
610 	/*
611 	 * Return, if previously selected slave device is same as current
612 	 * requested slave device.
613 	 */
614 	if (f->selected == spi->chip_select)
615 		return;
616 
617 	/* Reset FLSHxxCR0 registers */
618 	fspi_writel(f, 0, f->iobase + FSPI_FLSHA1CR0);
619 	fspi_writel(f, 0, f->iobase + FSPI_FLSHA2CR0);
620 	fspi_writel(f, 0, f->iobase + FSPI_FLSHB1CR0);
621 	fspi_writel(f, 0, f->iobase + FSPI_FLSHB2CR0);
622 
623 	/* Assign controller memory mapped space as size, KBytes, of flash. */
624 	size_kb = FSPI_FLSHXCR0_SZ(f->memmap_phy_size);
625 
626 	fspi_writel(f, size_kb, f->iobase + FSPI_FLSHA1CR0 +
627 		    4 * spi->chip_select);
628 
629 	dev_dbg(f->dev, "Slave device [CS:%x] selected\n", spi->chip_select);
630 
631 	nxp_fspi_clk_disable_unprep(f);
632 
633 	ret = clk_set_rate(f->clk, rate);
634 	if (ret)
635 		return;
636 
637 	ret = nxp_fspi_clk_prep_enable(f);
638 	if (ret)
639 		return;
640 
641 	f->selected = spi->chip_select;
642 }
643 
644 static void nxp_fspi_read_ahb(struct nxp_fspi *f, const struct spi_mem_op *op)
645 {
646 	u32 len = op->data.nbytes;
647 
648 	/* Read out the data directly from the AHB buffer. */
649 	memcpy_fromio(op->data.buf.in, (f->ahb_addr + op->addr.val), len);
650 }
651 
652 static void nxp_fspi_fill_txfifo(struct nxp_fspi *f,
653 				 const struct spi_mem_op *op)
654 {
655 	void __iomem *base = f->iobase;
656 	int i, ret;
657 	u8 *buf = (u8 *) op->data.buf.out;
658 
659 	/* clear the TX FIFO. */
660 	fspi_writel(f, FSPI_IPTXFCR_CLR, base + FSPI_IPTXFCR);
661 
662 	/*
663 	 * Default value of water mark level is 8 bytes, hence in single
664 	 * write request controller can write max 8 bytes of data.
665 	 */
666 
667 	for (i = 0; i < ALIGN_DOWN(op->data.nbytes, 8); i += 8) {
668 		/* Wait for TXFIFO empty */
669 		ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
670 					   FSPI_INTR_IPTXWE, 0,
671 					   POLL_TOUT, true);
672 		WARN_ON(ret);
673 
674 		fspi_writel(f, *(u32 *) (buf + i), base + FSPI_TFDR);
675 		fspi_writel(f, *(u32 *) (buf + i + 4), base + FSPI_TFDR + 4);
676 		fspi_writel(f, FSPI_INTR_IPTXWE, base + FSPI_INTR);
677 	}
678 
679 	if (i < op->data.nbytes) {
680 		u32 data = 0;
681 		int j;
682 		/* Wait for TXFIFO empty */
683 		ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
684 					   FSPI_INTR_IPTXWE, 0,
685 					   POLL_TOUT, true);
686 		WARN_ON(ret);
687 
688 		for (j = 0; j < ALIGN(op->data.nbytes - i, 4); j += 4) {
689 			memcpy(&data, buf + i + j, 4);
690 			fspi_writel(f, data, base + FSPI_TFDR + j);
691 		}
692 		fspi_writel(f, FSPI_INTR_IPTXWE, base + FSPI_INTR);
693 	}
694 }
695 
696 static void nxp_fspi_read_rxfifo(struct nxp_fspi *f,
697 			  const struct spi_mem_op *op)
698 {
699 	void __iomem *base = f->iobase;
700 	int i, ret;
701 	int len = op->data.nbytes;
702 	u8 *buf = (u8 *) op->data.buf.in;
703 
704 	/*
705 	 * Default value of water mark level is 8 bytes, hence in single
706 	 * read request controller can read max 8 bytes of data.
707 	 */
708 	for (i = 0; i < ALIGN_DOWN(len, 8); i += 8) {
709 		/* Wait for RXFIFO available */
710 		ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
711 					   FSPI_INTR_IPRXWA, 0,
712 					   POLL_TOUT, true);
713 		WARN_ON(ret);
714 
715 		*(u32 *)(buf + i) = fspi_readl(f, base + FSPI_RFDR);
716 		*(u32 *)(buf + i + 4) = fspi_readl(f, base + FSPI_RFDR + 4);
717 		/* move the FIFO pointer */
718 		fspi_writel(f, FSPI_INTR_IPRXWA, base + FSPI_INTR);
719 	}
720 
721 	if (i < len) {
722 		u32 tmp;
723 		int size, j;
724 
725 		buf = op->data.buf.in + i;
726 		/* Wait for RXFIFO available */
727 		ret = fspi_readl_poll_tout(f, f->iobase + FSPI_INTR,
728 					   FSPI_INTR_IPRXWA, 0,
729 					   POLL_TOUT, true);
730 		WARN_ON(ret);
731 
732 		len = op->data.nbytes - i;
733 		for (j = 0; j < op->data.nbytes - i; j += 4) {
734 			tmp = fspi_readl(f, base + FSPI_RFDR + j);
735 			size = min(len, 4);
736 			memcpy(buf + j, &tmp, size);
737 			len -= size;
738 		}
739 	}
740 
741 	/* invalid the RXFIFO */
742 	fspi_writel(f, FSPI_IPRXFCR_CLR, base + FSPI_IPRXFCR);
743 	/* move the FIFO pointer */
744 	fspi_writel(f, FSPI_INTR_IPRXWA, base + FSPI_INTR);
745 }
746 
747 static int nxp_fspi_do_op(struct nxp_fspi *f, const struct spi_mem_op *op)
748 {
749 	void __iomem *base = f->iobase;
750 	int seqnum = 0;
751 	int err = 0;
752 	u32 reg;
753 
754 	reg = fspi_readl(f, base + FSPI_IPRXFCR);
755 	/* invalid RXFIFO first */
756 	reg &= ~FSPI_IPRXFCR_DMA_EN;
757 	reg = reg | FSPI_IPRXFCR_CLR;
758 	fspi_writel(f, reg, base + FSPI_IPRXFCR);
759 
760 	init_completion(&f->c);
761 
762 	fspi_writel(f, op->addr.val, base + FSPI_IPCR0);
763 	/*
764 	 * Always start the sequence at the same index since we update
765 	 * the LUT at each exec_op() call. And also specify the DATA
766 	 * length, since it's has not been specified in the LUT.
767 	 */
768 	fspi_writel(f, op->data.nbytes |
769 		 (SEQID_LUT << FSPI_IPCR1_SEQID_SHIFT) |
770 		 (seqnum << FSPI_IPCR1_SEQNUM_SHIFT),
771 		 base + FSPI_IPCR1);
772 
773 	/* Trigger the LUT now. */
774 	fspi_writel(f, FSPI_IPCMD_TRG, base + FSPI_IPCMD);
775 
776 	/* Wait for the interrupt. */
777 	if (!wait_for_completion_timeout(&f->c, msecs_to_jiffies(1000)))
778 		err = -ETIMEDOUT;
779 
780 	/* Invoke IP data read, if request is of data read. */
781 	if (!err && op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN)
782 		nxp_fspi_read_rxfifo(f, op);
783 
784 	return err;
785 }
786 
787 static int nxp_fspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
788 {
789 	struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
790 	int err = 0;
791 
792 	mutex_lock(&f->lock);
793 
794 	/* Wait for controller being ready. */
795 	err = fspi_readl_poll_tout(f, f->iobase + FSPI_STS0,
796 				   FSPI_STS0_ARB_IDLE, 1, POLL_TOUT, true);
797 	WARN_ON(err);
798 
799 	nxp_fspi_select_mem(f, mem->spi);
800 
801 	nxp_fspi_prepare_lut(f, op);
802 	/*
803 	 * If we have large chunks of data, we read them through the AHB bus
804 	 * by accessing the mapped memory. In all other cases we use
805 	 * IP commands to access the flash.
806 	 */
807 	if (op->data.nbytes > (f->devtype_data->rxfifo - 4) &&
808 	    op->data.dir == SPI_MEM_DATA_IN) {
809 		nxp_fspi_read_ahb(f, op);
810 	} else {
811 		if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
812 			nxp_fspi_fill_txfifo(f, op);
813 
814 		err = nxp_fspi_do_op(f, op);
815 	}
816 
817 	/* Invalidate the data in the AHB buffer. */
818 	nxp_fspi_invalid(f);
819 
820 	mutex_unlock(&f->lock);
821 
822 	return err;
823 }
824 
825 static int nxp_fspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
826 {
827 	struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
828 
829 	if (op->data.dir == SPI_MEM_DATA_OUT) {
830 		if (op->data.nbytes > f->devtype_data->txfifo)
831 			op->data.nbytes = f->devtype_data->txfifo;
832 	} else {
833 		if (op->data.nbytes > f->devtype_data->ahb_buf_size)
834 			op->data.nbytes = f->devtype_data->ahb_buf_size;
835 		else if (op->data.nbytes > (f->devtype_data->rxfifo - 4))
836 			op->data.nbytes = ALIGN_DOWN(op->data.nbytes, 8);
837 	}
838 
839 	return 0;
840 }
841 
842 static int nxp_fspi_default_setup(struct nxp_fspi *f)
843 {
844 	void __iomem *base = f->iobase;
845 	int ret, i;
846 	u32 reg;
847 
848 	/* disable and unprepare clock to avoid glitch pass to controller */
849 	nxp_fspi_clk_disable_unprep(f);
850 
851 	/* the default frequency, we will change it later if necessary. */
852 	ret = clk_set_rate(f->clk, 20000000);
853 	if (ret)
854 		return ret;
855 
856 	ret = nxp_fspi_clk_prep_enable(f);
857 	if (ret)
858 		return ret;
859 
860 	/* Reset the module */
861 	/* w1c register, wait unit clear */
862 	ret = fspi_readl_poll_tout(f, f->iobase + FSPI_MCR0,
863 				   FSPI_MCR0_SWRST, 0, POLL_TOUT, false);
864 	WARN_ON(ret);
865 
866 	/* Disable the module */
867 	fspi_writel(f, FSPI_MCR0_MDIS, base + FSPI_MCR0);
868 
869 	/* Reset the DLL register to default value */
870 	fspi_writel(f, FSPI_DLLACR_OVRDEN, base + FSPI_DLLACR);
871 	fspi_writel(f, FSPI_DLLBCR_OVRDEN, base + FSPI_DLLBCR);
872 
873 	/* enable module */
874 	fspi_writel(f, FSPI_MCR0_AHB_TIMEOUT(0xFF) | FSPI_MCR0_IP_TIMEOUT(0xFF),
875 		 base + FSPI_MCR0);
876 
877 	/*
878 	 * Disable same device enable bit and configure all slave devices
879 	 * independently.
880 	 */
881 	reg = fspi_readl(f, f->iobase + FSPI_MCR2);
882 	reg = reg & ~(FSPI_MCR2_SAMEDEVICEEN);
883 	fspi_writel(f, reg, base + FSPI_MCR2);
884 
885 	/* AHB configuration for access buffer 0~7. */
886 	for (i = 0; i < 7; i++)
887 		fspi_writel(f, 0, base + FSPI_AHBRX_BUF0CR0 + 4 * i);
888 
889 	/*
890 	 * Set ADATSZ with the maximum AHB buffer size to improve the read
891 	 * performance.
892 	 */
893 	fspi_writel(f, (f->devtype_data->ahb_buf_size / 8 |
894 		  FSPI_AHBRXBUF0CR7_PREF), base + FSPI_AHBRX_BUF7CR0);
895 
896 	/* prefetch and no start address alignment limitation */
897 	fspi_writel(f, FSPI_AHBCR_PREF_EN | FSPI_AHBCR_RDADDROPT,
898 		 base + FSPI_AHBCR);
899 
900 	/* AHB Read - Set lut sequence ID for all CS. */
901 	fspi_writel(f, SEQID_LUT, base + FSPI_FLSHA1CR2);
902 	fspi_writel(f, SEQID_LUT, base + FSPI_FLSHA2CR2);
903 	fspi_writel(f, SEQID_LUT, base + FSPI_FLSHB1CR2);
904 	fspi_writel(f, SEQID_LUT, base + FSPI_FLSHB2CR2);
905 
906 	f->selected = -1;
907 
908 	/* enable the interrupt */
909 	fspi_writel(f, FSPI_INTEN_IPCMDDONE, base + FSPI_INTEN);
910 
911 	return 0;
912 }
913 
914 static const char *nxp_fspi_get_name(struct spi_mem *mem)
915 {
916 	struct nxp_fspi *f = spi_controller_get_devdata(mem->spi->master);
917 	struct device *dev = &mem->spi->dev;
918 	const char *name;
919 
920 	// Set custom name derived from the platform_device of the controller.
921 	if (of_get_available_child_count(f->dev->of_node) == 1)
922 		return dev_name(f->dev);
923 
924 	name = devm_kasprintf(dev, GFP_KERNEL,
925 			      "%s-%d", dev_name(f->dev),
926 			      mem->spi->chip_select);
927 
928 	if (!name) {
929 		dev_err(dev, "failed to get memory for custom flash name\n");
930 		return ERR_PTR(-ENOMEM);
931 	}
932 
933 	return name;
934 }
935 
936 static const struct spi_controller_mem_ops nxp_fspi_mem_ops = {
937 	.adjust_op_size = nxp_fspi_adjust_op_size,
938 	.supports_op = nxp_fspi_supports_op,
939 	.exec_op = nxp_fspi_exec_op,
940 	.get_name = nxp_fspi_get_name,
941 };
942 
943 static int nxp_fspi_probe(struct platform_device *pdev)
944 {
945 	struct spi_controller *ctlr;
946 	struct device *dev = &pdev->dev;
947 	struct device_node *np = dev->of_node;
948 	struct resource *res;
949 	struct nxp_fspi *f;
950 	int ret;
951 
952 	ctlr = spi_alloc_master(&pdev->dev, sizeof(*f));
953 	if (!ctlr)
954 		return -ENOMEM;
955 
956 	ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL |
957 			  SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL;
958 
959 	f = spi_controller_get_devdata(ctlr);
960 	f->dev = dev;
961 	f->devtype_data = of_device_get_match_data(dev);
962 	if (!f->devtype_data) {
963 		ret = -ENODEV;
964 		goto err_put_ctrl;
965 	}
966 
967 	platform_set_drvdata(pdev, f);
968 
969 	/* find the resources - configuration register address space */
970 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fspi_base");
971 	f->iobase = devm_ioremap_resource(dev, res);
972 	if (IS_ERR(f->iobase)) {
973 		ret = PTR_ERR(f->iobase);
974 		goto err_put_ctrl;
975 	}
976 
977 	/* find the resources - controller memory mapped space */
978 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fspi_mmap");
979 	f->ahb_addr = devm_ioremap_resource(dev, res);
980 	if (IS_ERR(f->ahb_addr)) {
981 		ret = PTR_ERR(f->ahb_addr);
982 		goto err_put_ctrl;
983 	}
984 
985 	/* assign memory mapped starting address and mapped size. */
986 	f->memmap_phy = res->start;
987 	f->memmap_phy_size = resource_size(res);
988 
989 	/* find the clocks */
990 	f->clk_en = devm_clk_get(dev, "fspi_en");
991 	if (IS_ERR(f->clk_en)) {
992 		ret = PTR_ERR(f->clk_en);
993 		goto err_put_ctrl;
994 	}
995 
996 	f->clk = devm_clk_get(dev, "fspi");
997 	if (IS_ERR(f->clk)) {
998 		ret = PTR_ERR(f->clk);
999 		goto err_put_ctrl;
1000 	}
1001 
1002 	ret = nxp_fspi_clk_prep_enable(f);
1003 	if (ret) {
1004 		dev_err(dev, "can not enable the clock\n");
1005 		goto err_put_ctrl;
1006 	}
1007 
1008 	/* find the irq */
1009 	ret = platform_get_irq(pdev, 0);
1010 	if (ret < 0) {
1011 		dev_err(dev, "failed to get the irq: %d\n", ret);
1012 		goto err_disable_clk;
1013 	}
1014 
1015 	ret = devm_request_irq(dev, ret,
1016 			nxp_fspi_irq_handler, 0, pdev->name, f);
1017 	if (ret) {
1018 		dev_err(dev, "failed to request irq: %d\n", ret);
1019 		goto err_disable_clk;
1020 	}
1021 
1022 	mutex_init(&f->lock);
1023 
1024 	ctlr->bus_num = -1;
1025 	ctlr->num_chipselect = NXP_FSPI_MAX_CHIPSELECT;
1026 	ctlr->mem_ops = &nxp_fspi_mem_ops;
1027 
1028 	nxp_fspi_default_setup(f);
1029 
1030 	ctlr->dev.of_node = np;
1031 
1032 	ret = spi_register_controller(ctlr);
1033 	if (ret)
1034 		goto err_destroy_mutex;
1035 
1036 	return 0;
1037 
1038 err_destroy_mutex:
1039 	mutex_destroy(&f->lock);
1040 
1041 err_disable_clk:
1042 	nxp_fspi_clk_disable_unprep(f);
1043 
1044 err_put_ctrl:
1045 	spi_controller_put(ctlr);
1046 
1047 	dev_err(dev, "NXP FSPI probe failed\n");
1048 	return ret;
1049 }
1050 
1051 static int nxp_fspi_remove(struct platform_device *pdev)
1052 {
1053 	struct nxp_fspi *f = platform_get_drvdata(pdev);
1054 
1055 	/* disable the hardware */
1056 	fspi_writel(f, FSPI_MCR0_MDIS, f->iobase + FSPI_MCR0);
1057 
1058 	nxp_fspi_clk_disable_unprep(f);
1059 
1060 	mutex_destroy(&f->lock);
1061 
1062 	return 0;
1063 }
1064 
1065 static int nxp_fspi_suspend(struct device *dev)
1066 {
1067 	return 0;
1068 }
1069 
1070 static int nxp_fspi_resume(struct device *dev)
1071 {
1072 	struct nxp_fspi *f = dev_get_drvdata(dev);
1073 
1074 	nxp_fspi_default_setup(f);
1075 
1076 	return 0;
1077 }
1078 
1079 static const struct of_device_id nxp_fspi_dt_ids[] = {
1080 	{ .compatible = "nxp,lx2160a-fspi", .data = (void *)&lx2160a_data, },
1081 	{ /* sentinel */ }
1082 };
1083 MODULE_DEVICE_TABLE(of, nxp_fspi_dt_ids);
1084 
1085 static const struct dev_pm_ops nxp_fspi_pm_ops = {
1086 	.suspend	= nxp_fspi_suspend,
1087 	.resume		= nxp_fspi_resume,
1088 };
1089 
1090 static struct platform_driver nxp_fspi_driver = {
1091 	.driver = {
1092 		.name	= "nxp-fspi",
1093 		.of_match_table = nxp_fspi_dt_ids,
1094 		.pm =   &nxp_fspi_pm_ops,
1095 	},
1096 	.probe          = nxp_fspi_probe,
1097 	.remove		= nxp_fspi_remove,
1098 };
1099 module_platform_driver(nxp_fspi_driver);
1100 
1101 MODULE_DESCRIPTION("NXP FSPI Controller Driver");
1102 MODULE_AUTHOR("NXP Semiconductor");
1103 MODULE_AUTHOR("Yogesh Narayan Gaur <yogeshnarayan.gaur@nxp.com>");
1104 MODULE_AUTHOR("Boris Brezillon <bbrezillon@kernel.org>");
1105 MODULE_AUTHOR("Frieder Schrempf <frieder.schrempf@kontron.de>");
1106 MODULE_LICENSE("GPL v2");
1107