1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Renesas RCar Gen3 RPC QSPI driver
4  *
5  * Copyright (C) 2018 Marek Vasut <marek.vasut@gmail.com>
6  */
7 
8 #include <common.h>
9 #include <asm/global_data.h>
10 #include <asm/io.h>
11 #include <clk.h>
12 #include <dm.h>
13 #include <dm/of_access.h>
14 #include <dt-structs.h>
15 #include <errno.h>
16 #include <linux/bitops.h>
17 #include <linux/bug.h>
18 #include <linux/errno.h>
19 #include <spi.h>
20 #include <wait_bit.h>
21 
22 #define RPC_CMNCR		0x0000	/* R/W */
23 #define RPC_CMNCR_MD		BIT(31)
24 #define RPC_CMNCR_SFDE		BIT(24)
25 #define RPC_CMNCR_MOIIO3(val)	(((val) & 0x3) << 22)
26 #define RPC_CMNCR_MOIIO2(val)	(((val) & 0x3) << 20)
27 #define RPC_CMNCR_MOIIO1(val)	(((val) & 0x3) << 18)
28 #define RPC_CMNCR_MOIIO0(val)	(((val) & 0x3) << 16)
29 #define RPC_CMNCR_MOIIO_HIZ	(RPC_CMNCR_MOIIO0(3) | RPC_CMNCR_MOIIO1(3) | \
30 				 RPC_CMNCR_MOIIO2(3) | RPC_CMNCR_MOIIO3(3))
31 #define RPC_CMNCR_IO3FV(val)	(((val) & 0x3) << 14)
32 #define RPC_CMNCR_IO2FV(val)	(((val) & 0x3) << 12)
33 #define RPC_CMNCR_IO0FV(val)	(((val) & 0x3) << 8)
34 #define RPC_CMNCR_IOFV_HIZ	(RPC_CMNCR_IO0FV(3) | RPC_CMNCR_IO2FV(3) | \
35 				 RPC_CMNCR_IO3FV(3))
36 #define RPC_CMNCR_CPHAT		BIT(6)
37 #define RPC_CMNCR_CPHAR		BIT(5)
38 #define RPC_CMNCR_SSLP		BIT(4)
39 #define RPC_CMNCR_CPOL		BIT(3)
40 #define RPC_CMNCR_BSZ(val)	(((val) & 0x3) << 0)
41 
42 #define RPC_SSLDR		0x0004	/* R/W */
43 #define RPC_SSLDR_SPNDL(d)	(((d) & 0x7) << 16)
44 #define RPC_SSLDR_SLNDL(d)	(((d) & 0x7) << 8)
45 #define RPC_SSLDR_SCKDL(d)	(((d) & 0x7) << 0)
46 
47 #define RPC_DRCR		0x000C	/* R/W */
48 #define RPC_DRCR_SSLN		BIT(24)
49 #define RPC_DRCR_RBURST(v)	(((v) & 0x1F) << 16)
50 #define RPC_DRCR_RCF		BIT(9)
51 #define RPC_DRCR_RBE		BIT(8)
52 #define RPC_DRCR_SSLE		BIT(0)
53 
54 #define RPC_DRCMR		0x0010	/* R/W */
55 #define RPC_DRCMR_CMD(c)	(((c) & 0xFF) << 16)
56 #define RPC_DRCMR_OCMD(c)	(((c) & 0xFF) << 0)
57 
58 #define RPC_DREAR		0x0014	/* R/W */
59 #define RPC_DREAR_EAV(v)	(((v) & 0xFF) << 16)
60 #define RPC_DREAR_EAC(v)	(((v) & 0x7) << 0)
61 
62 #define RPC_DROPR		0x0018	/* R/W */
63 #define RPC_DROPR_OPD3(o)	(((o) & 0xFF) << 24)
64 #define RPC_DROPR_OPD2(o)	(((o) & 0xFF) << 16)
65 #define RPC_DROPR_OPD1(o)	(((o) & 0xFF) << 8)
66 #define RPC_DROPR_OPD0(o)	(((o) & 0xFF) << 0)
67 
68 #define RPC_DRENR		0x001C	/* R/W */
69 #define RPC_DRENR_CDB(o)	(u32)((((o) & 0x3) << 30))
70 #define RPC_DRENR_OCDB(o)	(((o) & 0x3) << 28)
71 #define RPC_DRENR_ADB(o)	(((o) & 0x3) << 24)
72 #define RPC_DRENR_OPDB(o)	(((o) & 0x3) << 20)
73 #define RPC_DRENR_SPIDB(o)	(((o) & 0x3) << 16)
74 #define RPC_DRENR_DME		BIT(15)
75 #define RPC_DRENR_CDE		BIT(14)
76 #define RPC_DRENR_OCDE		BIT(12)
77 #define RPC_DRENR_ADE(v)	(((v) & 0xF) << 8)
78 #define RPC_DRENR_OPDE(v)	(((v) & 0xF) << 4)
79 
80 #define RPC_SMCR		0x0020	/* R/W */
81 #define RPC_SMCR_SSLKP		BIT(8)
82 #define RPC_SMCR_SPIRE		BIT(2)
83 #define RPC_SMCR_SPIWE		BIT(1)
84 #define RPC_SMCR_SPIE		BIT(0)
85 
86 #define RPC_SMCMR		0x0024	/* R/W */
87 #define RPC_SMCMR_CMD(c)	(((c) & 0xFF) << 16)
88 #define RPC_SMCMR_OCMD(c)	(((c) & 0xFF) << 0)
89 
90 #define RPC_SMADR		0x0028	/* R/W */
91 #define RPC_SMOPR		0x002C	/* R/W */
92 #define RPC_SMOPR_OPD0(o)	(((o) & 0xFF) << 0)
93 #define RPC_SMOPR_OPD1(o)	(((o) & 0xFF) << 8)
94 #define RPC_SMOPR_OPD2(o)	(((o) & 0xFF) << 16)
95 #define RPC_SMOPR_OPD3(o)	(((o) & 0xFF) << 24)
96 
97 #define RPC_SMENR		0x0030	/* R/W */
98 #define RPC_SMENR_CDB(o)	(((o) & 0x3) << 30)
99 #define RPC_SMENR_OCDB(o)	(((o) & 0x3) << 28)
100 #define RPC_SMENR_ADB(o)	(((o) & 0x3) << 24)
101 #define RPC_SMENR_OPDB(o)	(((o) & 0x3) << 20)
102 #define RPC_SMENR_SPIDB(o)	(((o) & 0x3) << 16)
103 #define RPC_SMENR_DME		BIT(15)
104 #define RPC_SMENR_CDE		BIT(14)
105 #define RPC_SMENR_OCDE		BIT(12)
106 #define RPC_SMENR_ADE(v)	(((v) & 0xF) << 8)
107 #define RPC_SMENR_OPDE(v)	(((v) & 0xF) << 4)
108 #define RPC_SMENR_SPIDE(v)	(((v) & 0xF) << 0)
109 
110 #define RPC_SMRDR0		0x0038	/* R */
111 #define RPC_SMRDR1		0x003C	/* R */
112 #define RPC_SMWDR0		0x0040	/* R/W */
113 #define RPC_SMWDR1		0x0044	/* R/W */
114 #define RPC_CMNSR		0x0048	/* R */
115 #define RPC_CMNSR_SSLF		BIT(1)
116 #define	RPC_CMNSR_TEND		BIT(0)
117 
118 #define RPC_DRDMCR		0x0058	/* R/W */
119 #define RPC_DRDMCR_DMCYC(v)	(((v) & 0xF) << 0)
120 
121 #define RPC_DRDRENR		0x005C	/* R/W */
122 #define RPC_DRDRENR_HYPE	(0x5 << 12)
123 #define RPC_DRDRENR_ADDRE	BIT(8)
124 #define RPC_DRDRENR_OPDRE	BIT(4)
125 #define RPC_DRDRENR_DRDRE	BIT(0)
126 
127 #define RPC_SMDMCR		0x0060	/* R/W */
128 #define RPC_SMDMCR_DMCYC(v)	(((v) & 0xF) << 0)
129 
130 #define RPC_SMDRENR		0x0064	/* R/W */
131 #define RPC_SMDRENR_HYPE	(0x5 << 12)
132 #define RPC_SMDRENR_ADDRE	BIT(8)
133 #define RPC_SMDRENR_OPDRE	BIT(4)
134 #define RPC_SMDRENR_SPIDRE	BIT(0)
135 
136 #define RPC_PHYCNT		0x007C	/* R/W */
137 #define RPC_PHYCNT_CAL		BIT(31)
138 #define PRC_PHYCNT_OCTA_AA	BIT(22)
139 #define PRC_PHYCNT_OCTA_SA	BIT(23)
140 #define PRC_PHYCNT_EXDS		BIT(21)
141 #define RPC_PHYCNT_OCT		BIT(20)
142 #define RPC_PHYCNT_STRTIM(v)	(((v) & 0x7) << 15)
143 #define RPC_PHYCNT_WBUF2	BIT(4)
144 #define RPC_PHYCNT_WBUF		BIT(2)
145 #define RPC_PHYCNT_MEM(v)	(((v) & 0x3) << 0)
146 
147 #define RPC_PHYINT		0x0088	/* R/W */
148 #define RPC_PHYINT_RSTEN	BIT(18)
149 #define RPC_PHYINT_WPEN		BIT(17)
150 #define RPC_PHYINT_INTEN	BIT(16)
151 #define RPC_PHYINT_RST		BIT(2)
152 #define RPC_PHYINT_WP		BIT(1)
153 #define RPC_PHYINT_INT		BIT(0)
154 
155 #define RPC_WBUF		0x8000	/* R/W size=4/8/16/32/64Bytes */
156 #define RPC_WBUF_SIZE		0x100
157 
158 DECLARE_GLOBAL_DATA_PTR;
159 
160 struct rpc_spi_plat {
161 	fdt_addr_t	regs;
162 	fdt_addr_t	extr;
163 	s32		freq;	/* Default clock freq, -1 for none */
164 };
165 
166 struct rpc_spi_priv {
167 	fdt_addr_t	regs;
168 	fdt_addr_t	extr;
169 	struct clk	clk;
170 
171 	u8		cmdcopy[8];
172 	u32		cmdlen;
173 	bool		cmdstarted;
174 };
175 
rpc_spi_wait_sslf(struct udevice * dev)176 static int rpc_spi_wait_sslf(struct udevice *dev)
177 {
178 	struct rpc_spi_priv *priv = dev_get_priv(dev->parent);
179 
180 	return wait_for_bit_le32((void *)priv->regs + RPC_CMNSR, RPC_CMNSR_SSLF,
181 				 false, 1000, false);
182 }
183 
rpc_spi_wait_tend(struct udevice * dev)184 static int rpc_spi_wait_tend(struct udevice *dev)
185 {
186 	struct rpc_spi_priv *priv = dev_get_priv(dev->parent);
187 
188 	return wait_for_bit_le32((void *)priv->regs + RPC_CMNSR, RPC_CMNSR_TEND,
189 				 true, 1000, false);
190 }
191 
rpc_spi_flush_read_cache(struct udevice * dev)192 static void rpc_spi_flush_read_cache(struct udevice *dev)
193 {
194 	struct udevice *bus = dev->parent;
195 	struct rpc_spi_priv *priv = dev_get_priv(bus);
196 
197 	/* Flush read cache */
198 	writel(RPC_DRCR_SSLN | RPC_DRCR_RBURST(0x1f) |
199 	       RPC_DRCR_RCF | RPC_DRCR_RBE | RPC_DRCR_SSLE,
200 	       priv->regs + RPC_DRCR);
201 	readl(priv->regs + RPC_DRCR);
202 
203 }
204 
rpc_spi_claim_bus(struct udevice * dev,bool manual)205 static int rpc_spi_claim_bus(struct udevice *dev, bool manual)
206 {
207 	struct udevice *bus = dev->parent;
208 	struct rpc_spi_priv *priv = dev_get_priv(bus);
209 
210 	/*
211 	 * NOTE: The 0x260 are undocumented bits, but they must be set.
212 	 * NOTE: On H3 ES1.x (not supported in mainline U-Boot), the
213 	 *       RPC_PHYCNT_STRTIM shall be 0, while on newer parts, the
214 	 *       RPC_PHYCNT_STRTIM shall be 6.
215 	 */
216 	writel(RPC_PHYCNT_CAL | RPC_PHYCNT_STRTIM(6) | 0x260,
217 	       priv->regs + RPC_PHYCNT);
218 	writel((manual ? RPC_CMNCR_MD : 0) | RPC_CMNCR_SFDE |
219 		 RPC_CMNCR_MOIIO_HIZ | RPC_CMNCR_IOFV_HIZ | RPC_CMNCR_BSZ(0),
220 		 priv->regs + RPC_CMNCR);
221 
222 	writel(RPC_SSLDR_SPNDL(7) | RPC_SSLDR_SLNDL(7) |
223 	       RPC_SSLDR_SCKDL(7), priv->regs + RPC_SSLDR);
224 
225 	rpc_spi_flush_read_cache(dev);
226 
227 	return 0;
228 }
229 
rpc_spi_release_bus(struct udevice * dev)230 static int rpc_spi_release_bus(struct udevice *dev)
231 {
232 	struct udevice *bus = dev->parent;
233 	struct rpc_spi_priv *priv = dev_get_priv(bus);
234 
235 	/* NOTE: The 0x260 are undocumented bits, but they must be set. */
236 	writel(RPC_PHYCNT_STRTIM(6) | 0x260, priv->regs + RPC_PHYCNT);
237 
238 	rpc_spi_flush_read_cache(dev);
239 
240 	return 0;
241 }
242 
rpc_spi_xfer(struct udevice * dev,unsigned int bitlen,const void * dout,void * din,unsigned long flags)243 static int rpc_spi_xfer(struct udevice *dev, unsigned int bitlen,
244 			const void *dout, void *din, unsigned long flags)
245 {
246 	struct udevice *bus = dev->parent;
247 	struct rpc_spi_priv *priv = dev_get_priv(bus);
248 	u32 wlen = dout ? (bitlen / 8) : 0;
249 	u32 rlen = din ? (bitlen / 8) : 0;
250 	u32 wloop = DIV_ROUND_UP(wlen, 4);
251 	u32 smenr, smcr, offset;
252 	int ret = 0;
253 
254 	if (!priv->cmdstarted) {
255 		if (!wlen || rlen)
256 			BUG();
257 
258 		memcpy(priv->cmdcopy, dout, wlen);
259 		priv->cmdlen = wlen;
260 
261 		/* Command transfer start */
262 		priv->cmdstarted = true;
263 		if (!(flags & SPI_XFER_END))
264 			return 0;
265 	}
266 
267 	offset = (priv->cmdcopy[1] << 16) | (priv->cmdcopy[2] << 8) |
268 		 (priv->cmdcopy[3] << 0);
269 
270 	smenr = 0;
271 
272 	if (wlen || (!rlen && !wlen) || flags == SPI_XFER_ONCE) {
273 		if (wlen && flags == SPI_XFER_END)
274 			smenr = RPC_SMENR_SPIDE(0xf);
275 
276 		rpc_spi_claim_bus(dev, true);
277 
278 		writel(0, priv->regs + RPC_SMCR);
279 
280 		if (priv->cmdlen >= 1) {	/* Command(1) */
281 			writel(RPC_SMCMR_CMD(priv->cmdcopy[0]),
282 			       priv->regs + RPC_SMCMR);
283 			smenr |= RPC_SMENR_CDE;
284 		} else {
285 			writel(0, priv->regs + RPC_SMCMR);
286 		}
287 
288 		if (priv->cmdlen >= 4) {	/* Address(3) */
289 			writel(offset, priv->regs + RPC_SMADR);
290 			smenr |= RPC_SMENR_ADE(7);
291 		} else {
292 			writel(0, priv->regs + RPC_SMADR);
293 		}
294 
295 		if (priv->cmdlen >= 5) {	/* Dummy(n) */
296 			writel(8 * (priv->cmdlen - 4) - 1,
297 			       priv->regs + RPC_SMDMCR);
298 			smenr |= RPC_SMENR_DME;
299 		} else {
300 			writel(0, priv->regs + RPC_SMDMCR);
301 		}
302 
303 		writel(0, priv->regs + RPC_SMOPR);
304 
305 		writel(0, priv->regs + RPC_SMDRENR);
306 
307 		if (wlen && flags == SPI_XFER_END) {
308 			u32 *datout = (u32 *)dout;
309 
310 			while (wloop--) {
311 				smcr = RPC_SMCR_SPIWE | RPC_SMCR_SPIE;
312 				if (wloop >= 1)
313 					smcr |= RPC_SMCR_SSLKP;
314 				writel(smenr, priv->regs + RPC_SMENR);
315 				writel(*datout, priv->regs + RPC_SMWDR0);
316 				writel(smcr, priv->regs + RPC_SMCR);
317 				ret = rpc_spi_wait_tend(dev);
318 				if (ret)
319 					goto err;
320 				datout++;
321 				smenr = RPC_SMENR_SPIDE(0xf);
322 			}
323 
324 			ret = rpc_spi_wait_sslf(dev);
325 
326 		} else {
327 			writel(smenr, priv->regs + RPC_SMENR);
328 			writel(RPC_SMCR_SPIE, priv->regs + RPC_SMCR);
329 			ret = rpc_spi_wait_tend(dev);
330 		}
331 	} else {	/* Read data only, using DRx ext access */
332 		rpc_spi_claim_bus(dev, false);
333 
334 		if (priv->cmdlen >= 1) {	/* Command(1) */
335 			writel(RPC_DRCMR_CMD(priv->cmdcopy[0]),
336 			       priv->regs + RPC_DRCMR);
337 			smenr |= RPC_DRENR_CDE;
338 		} else {
339 			writel(0, priv->regs + RPC_DRCMR);
340 		}
341 
342 		if (priv->cmdlen >= 4)		/* Address(3) */
343 			smenr |= RPC_DRENR_ADE(7);
344 
345 		if (priv->cmdlen >= 5) {	/* Dummy(n) */
346 			writel(8 * (priv->cmdlen - 4) - 1,
347 			       priv->regs + RPC_DRDMCR);
348 			smenr |= RPC_DRENR_DME;
349 		} else {
350 			writel(0, priv->regs + RPC_DRDMCR);
351 		}
352 
353 		writel(0, priv->regs + RPC_DROPR);
354 
355 		writel(smenr, priv->regs + RPC_DRENR);
356 
357 		if (rlen)
358 			memcpy_fromio(din, (void *)(priv->extr + offset), rlen);
359 		else
360 			readl(priv->extr);	/* Dummy read */
361 	}
362 
363 err:
364 	priv->cmdstarted = false;
365 
366 	rpc_spi_release_bus(dev);
367 
368 	return ret;
369 }
370 
rpc_spi_set_speed(struct udevice * bus,uint speed)371 static int rpc_spi_set_speed(struct udevice *bus, uint speed)
372 {
373 	/* This is a SPI NOR controller, do nothing. */
374 	return 0;
375 }
376 
rpc_spi_set_mode(struct udevice * bus,uint mode)377 static int rpc_spi_set_mode(struct udevice *bus, uint mode)
378 {
379 	/* This is a SPI NOR controller, do nothing. */
380 	return 0;
381 }
382 
rpc_spi_bind(struct udevice * parent)383 static int rpc_spi_bind(struct udevice *parent)
384 {
385 	const void *fdt = gd->fdt_blob;
386 	ofnode node;
387 	int ret, off;
388 
389 	/*
390 	 * Check if there are any SPI NOR child nodes, if so, bind as
391 	 * this controller will be operated in SPI mode.
392 	 */
393 	dev_for_each_subnode(node, parent) {
394 		off = ofnode_to_offset(node);
395 
396 		ret = fdt_node_check_compatible(fdt, off, "spi-flash");
397 		if (!ret)
398 			return 0;
399 
400 		ret = fdt_node_check_compatible(fdt, off, "jedec,spi-nor");
401 		if (!ret)
402 			return 0;
403 	}
404 
405 	return -ENODEV;
406 }
407 
rpc_spi_probe(struct udevice * dev)408 static int rpc_spi_probe(struct udevice *dev)
409 {
410 	struct rpc_spi_plat *plat = dev_get_plat(dev);
411 	struct rpc_spi_priv *priv = dev_get_priv(dev);
412 
413 	priv->regs = plat->regs;
414 	priv->extr = plat->extr;
415 #if CONFIG_IS_ENABLED(CLK)
416 	clk_enable(&priv->clk);
417 #endif
418 	return 0;
419 }
420 
rpc_spi_of_to_plat(struct udevice * bus)421 static int rpc_spi_of_to_plat(struct udevice *bus)
422 {
423 	struct rpc_spi_plat *plat = dev_get_plat(bus);
424 
425 	plat->regs = dev_read_addr_index(bus, 0);
426 	plat->extr = dev_read_addr_index(bus, 1);
427 
428 #if CONFIG_IS_ENABLED(CLK)
429 	struct rpc_spi_priv *priv = dev_get_priv(bus);
430 	int ret;
431 
432 	ret = clk_get_by_index(bus, 0, &priv->clk);
433 	if (ret < 0) {
434 		printf("%s: Could not get clock for %s: %d\n",
435 		       __func__, bus->name, ret);
436 		return ret;
437 	}
438 #endif
439 
440 	plat->freq = dev_read_u32_default(bus, "spi-max-freq", 50000000);
441 
442 	return 0;
443 }
444 
445 static const struct dm_spi_ops rpc_spi_ops = {
446 	.xfer		= rpc_spi_xfer,
447 	.set_speed	= rpc_spi_set_speed,
448 	.set_mode	= rpc_spi_set_mode,
449 };
450 
451 static const struct udevice_id rpc_spi_ids[] = {
452 	{ .compatible = "renesas,rpc-r7s72100" },
453 	{ .compatible = "renesas,rpc-r8a7795" },
454 	{ .compatible = "renesas,rpc-r8a7796" },
455 	{ .compatible = "renesas,rpc-r8a77965" },
456 	{ .compatible = "renesas,rpc-r8a77970" },
457 	{ .compatible = "renesas,rpc-r8a77995" },
458 	{ .compatible = "renesas,rcar-gen3-rpc" },
459 	{ }
460 };
461 
462 U_BOOT_DRIVER(rpc_spi) = {
463 	.name		= "rpc_spi",
464 	.id		= UCLASS_SPI,
465 	.of_match	= rpc_spi_ids,
466 	.ops		= &rpc_spi_ops,
467 	.of_to_plat = rpc_spi_of_to_plat,
468 	.plat_auto	= sizeof(struct rpc_spi_plat),
469 	.priv_auto	= sizeof(struct rpc_spi_priv),
470 	.bind		= rpc_spi_bind,
471 	.probe		= rpc_spi_probe,
472 };
473