xref: /openbmc/u-boot/drivers/spi/kirkwood_spi.c (revision e23b19f4) 
1 /*
2  * (C) Copyright 2009
3  * Marvell Semiconductor <www.marvell.com>
4  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
5  *
6  * Derived from drivers/spi/mpc8xxx_spi.c
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <dm.h>
13 #include <malloc.h>
14 #include <spi.h>
15 #include <asm/io.h>
16 #include <asm/arch/soc.h>
17 #ifdef CONFIG_KIRKWOOD
18 #include <asm/arch/mpp.h>
19 #endif
20 #include <asm/arch-mvebu/spi.h>
21 
22 static void _spi_cs_activate(struct kwspi_registers *reg)
23 {
24 	setbits_le32(&reg->ctrl, KWSPI_CSN_ACT);
25 }
26 
27 static void _spi_cs_deactivate(struct kwspi_registers *reg)
28 {
29 	clrbits_le32(&reg->ctrl, KWSPI_CSN_ACT);
30 }
31 
32 static int _spi_xfer(struct kwspi_registers *reg, unsigned int bitlen,
33 		     const void *dout, void *din, unsigned long flags)
34 {
35 	unsigned int tmpdout, tmpdin;
36 	int tm, isread = 0;
37 
38 	debug("spi_xfer: dout %p din %p bitlen %u\n", dout, din, bitlen);
39 
40 	if (flags & SPI_XFER_BEGIN)
41 		_spi_cs_activate(reg);
42 
43 	/*
44 	 * handle data in 8-bit chunks
45 	 * TBD: 2byte xfer mode to be enabled
46 	 */
47 	clrsetbits_le32(&reg->cfg, KWSPI_XFERLEN_MASK, KWSPI_XFERLEN_1BYTE);
48 
49 	while (bitlen > 4) {
50 		debug("loopstart bitlen %d\n", bitlen);
51 		tmpdout = 0;
52 
53 		/* Shift data so it's msb-justified */
54 		if (dout)
55 			tmpdout = *(u32 *)dout & 0xff;
56 
57 		clrbits_le32(&reg->irq_cause, KWSPI_SMEMRDIRQ);
58 		writel(tmpdout, &reg->dout);	/* Write the data out */
59 		debug("*** spi_xfer: ... %08x written, bitlen %d\n",
60 		      tmpdout, bitlen);
61 
62 		/*
63 		 * Wait for SPI transmit to get out
64 		 * or time out (1 second = 1000 ms)
65 		 * The NE event must be read and cleared first
66 		 */
67 		for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) {
68 			if (readl(&reg->irq_cause) & KWSPI_SMEMRDIRQ) {
69 				isread = 1;
70 				tmpdin = readl(&reg->din);
71 				debug("spi_xfer: din %p..%08x read\n",
72 				      din, tmpdin);
73 
74 				if (din) {
75 					*((u8 *)din) = (u8)tmpdin;
76 					din += 1;
77 				}
78 				if (dout)
79 					dout += 1;
80 				bitlen -= 8;
81 			}
82 			if (isread)
83 				break;
84 		}
85 		if (tm >= KWSPI_TIMEOUT)
86 			printf("*** spi_xfer: Time out during SPI transfer\n");
87 
88 		debug("loopend bitlen %d\n", bitlen);
89 	}
90 
91 	if (flags & SPI_XFER_END)
92 		_spi_cs_deactivate(reg);
93 
94 	return 0;
95 }
96 
97 #ifndef CONFIG_DM_SPI
98 
99 static struct kwspi_registers *spireg =
100 	(struct kwspi_registers *)MVEBU_SPI_BASE;
101 
102 #ifdef CONFIG_KIRKWOOD
103 static u32 cs_spi_mpp_back[2];
104 #endif
105 
106 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
107 				unsigned int max_hz, unsigned int mode)
108 {
109 	struct spi_slave *slave;
110 	u32 data;
111 #ifdef CONFIG_KIRKWOOD
112 	static const u32 kwspi_mpp_config[2][2] = {
113 		{ MPP0_SPI_SCn, 0 }, /* if cs == 0 */
114 		{ MPP7_SPI_SCn, 0 } /* if cs != 0 */
115 	};
116 #endif
117 
118 	if (!spi_cs_is_valid(bus, cs))
119 		return NULL;
120 
121 	slave = spi_alloc_slave_base(bus, cs);
122 	if (!slave)
123 		return NULL;
124 
125 	writel(KWSPI_SMEMRDY, &spireg->ctrl);
126 
127 	/* calculate spi clock prescaller using max_hz */
128 	data = ((CONFIG_SYS_TCLK / 2) / max_hz) + 0x10;
129 	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
130 	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;
131 
132 	/* program spi clock prescaller using max_hz */
133 	writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg);
134 	debug("data = 0x%08x\n", data);
135 
136 	writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause);
137 	writel(KWSPI_IRQMASK, &spireg->irq_mask);
138 
139 #ifdef CONFIG_KIRKWOOD
140 	/* program mpp registers to select  SPI_CSn */
141 	kirkwood_mpp_conf(kwspi_mpp_config[cs ? 1 : 0], cs_spi_mpp_back);
142 #endif
143 
144 	return slave;
145 }
146 
147 void spi_free_slave(struct spi_slave *slave)
148 {
149 #ifdef CONFIG_KIRKWOOD
150 	kirkwood_mpp_conf(cs_spi_mpp_back, NULL);
151 #endif
152 	free(slave);
153 }
154 
155 #if defined(CONFIG_SYS_KW_SPI_MPP)
156 u32 spi_mpp_backup[4];
157 #endif
158 
159 __attribute__((weak)) int board_spi_claim_bus(struct spi_slave *slave)
160 {
161 	return 0;
162 }
163 
164 int spi_claim_bus(struct spi_slave *slave)
165 {
166 #if defined(CONFIG_SYS_KW_SPI_MPP)
167 	u32 config;
168 	u32 spi_mpp_config[4];
169 
170 	config = CONFIG_SYS_KW_SPI_MPP;
171 
172 	if (config & MOSI_MPP6)
173 		spi_mpp_config[0] = MPP6_SPI_MOSI;
174 	else
175 		spi_mpp_config[0] = MPP1_SPI_MOSI;
176 
177 	if (config & SCK_MPP10)
178 		spi_mpp_config[1] = MPP10_SPI_SCK;
179 	else
180 		spi_mpp_config[1] = MPP2_SPI_SCK;
181 
182 	if (config & MISO_MPP11)
183 		spi_mpp_config[2] = MPP11_SPI_MISO;
184 	else
185 		spi_mpp_config[2] = MPP3_SPI_MISO;
186 
187 	spi_mpp_config[3] = 0;
188 	spi_mpp_backup[3] = 0;
189 
190 	/* set new spi mpp and save current mpp config */
191 	kirkwood_mpp_conf(spi_mpp_config, spi_mpp_backup);
192 #endif
193 
194 	return board_spi_claim_bus(slave);
195 }
196 
197 __attribute__((weak)) void board_spi_release_bus(struct spi_slave *slave)
198 {
199 }
200 
201 void spi_release_bus(struct spi_slave *slave)
202 {
203 #if defined(CONFIG_SYS_KW_SPI_MPP)
204 	kirkwood_mpp_conf(spi_mpp_backup, NULL);
205 #endif
206 
207 	board_spi_release_bus(slave);
208 }
209 
210 #ifndef CONFIG_SPI_CS_IS_VALID
211 /*
212  * you can define this function board specific
213  * define above CONFIG in board specific config file and
214  * provide the function in board specific src file
215  */
216 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
217 {
218 	return bus == 0 && (cs == 0 || cs == 1);
219 }
220 #endif
221 
222 void spi_init(void)
223 {
224 }
225 
226 void spi_cs_activate(struct spi_slave *slave)
227 {
228 	_spi_cs_activate(spireg);
229 }
230 
231 void spi_cs_deactivate(struct spi_slave *slave)
232 {
233 	_spi_cs_deactivate(spireg);
234 }
235 
236 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
237 	     const void *dout, void *din, unsigned long flags)
238 {
239 	return _spi_xfer(spireg, bitlen, dout, din, flags);
240 }
241 
242 #else
243 
244 /* Here now the DM part */
245 
246 struct mvebu_spi_dev {
247 	bool			is_errata_50mhz_ac;
248 };
249 
250 struct mvebu_spi_platdata {
251 	struct kwspi_registers *spireg;
252 };
253 
254 struct mvebu_spi_priv {
255 	struct kwspi_registers *spireg;
256 };
257 
258 static int mvebu_spi_set_speed(struct udevice *bus, uint hz)
259 {
260 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
261 	struct kwspi_registers *reg = plat->spireg;
262 	u32 data;
263 
264 	/* calculate spi clock prescaller using max_hz */
265 	data = ((CONFIG_SYS_TCLK / 2) / hz) + 0x10;
266 	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
267 	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;
268 
269 	/* program spi clock prescaler using max_hz */
270 	writel(KWSPI_ADRLEN_3BYTE | data, &reg->cfg);
271 	debug("data = 0x%08x\n", data);
272 
273 	return 0;
274 }
275 
276 static void mvebu_spi_50mhz_ac_timing_erratum(struct udevice *bus, uint mode)
277 {
278 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
279 	struct kwspi_registers *reg = plat->spireg;
280 	u32 data;
281 
282 	/*
283 	 * Erratum description: (Erratum NO. FE-9144572) The device
284 	 * SPI interface supports frequencies of up to 50 MHz.
285 	 * However, due to this erratum, when the device core clock is
286 	 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
287 	 * clock and CPOL=CPHA=1 there might occur data corruption on
288 	 * reads from the SPI device.
289 	 * Erratum Workaround:
290 	 * Work in one of the following configurations:
291 	 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
292 	 * Register".
293 	 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
294 	 * Register" before setting the interface.
295 	 */
296 	data = readl(&reg->timing1);
297 	data &= ~KW_SPI_TMISO_SAMPLE_MASK;
298 
299 	if (CONFIG_SYS_TCLK == 250000000 &&
300 	    mode & SPI_CPOL &&
301 	    mode & SPI_CPHA)
302 		data |= KW_SPI_TMISO_SAMPLE_2;
303 	else
304 		data |= KW_SPI_TMISO_SAMPLE_1;
305 
306 	writel(data, &reg->timing1);
307 }
308 
309 static int mvebu_spi_set_mode(struct udevice *bus, uint mode)
310 {
311 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
312 	struct kwspi_registers *reg = plat->spireg;
313 	const struct mvebu_spi_dev *drvdata;
314 	u32 data = readl(&reg->cfg);
315 
316 	data &= ~(KWSPI_CPHA | KWSPI_CPOL | KWSPI_RXLSBF | KWSPI_TXLSBF);
317 
318 	if (mode & SPI_CPHA)
319 		data |= KWSPI_CPHA;
320 	if (mode & SPI_CPOL)
321 		data |= KWSPI_CPOL;
322 	if (mode & SPI_LSB_FIRST)
323 		data |= (KWSPI_RXLSBF | KWSPI_TXLSBF);
324 
325 	writel(data, &reg->cfg);
326 
327 	drvdata = (struct mvebu_spi_dev *)dev_get_driver_data(bus);
328 	if (drvdata->is_errata_50mhz_ac)
329 		mvebu_spi_50mhz_ac_timing_erratum(bus, mode);
330 
331 	return 0;
332 }
333 
334 static int mvebu_spi_xfer(struct udevice *dev, unsigned int bitlen,
335 			  const void *dout, void *din, unsigned long flags)
336 {
337 	struct udevice *bus = dev->parent;
338 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
339 
340 	return _spi_xfer(plat->spireg, bitlen, dout, din, flags);
341 }
342 
343 static int mvebu_spi_claim_bus(struct udevice *dev)
344 {
345 	struct udevice *bus = dev->parent;
346 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
347 
348 	/* Configure the chip-select in the CTRL register */
349 	clrsetbits_le32(&plat->spireg->ctrl,
350 			KWSPI_CS_MASK << KWSPI_CS_SHIFT,
351 			spi_chip_select(dev) << KWSPI_CS_SHIFT);
352 
353 	return 0;
354 }
355 
356 static int mvebu_spi_probe(struct udevice *bus)
357 {
358 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
359 	struct kwspi_registers *reg = plat->spireg;
360 
361 	writel(KWSPI_SMEMRDY, &reg->ctrl);
362 	writel(KWSPI_SMEMRDIRQ, &reg->irq_cause);
363 	writel(KWSPI_IRQMASK, &reg->irq_mask);
364 
365 	return 0;
366 }
367 
368 static int mvebu_spi_ofdata_to_platdata(struct udevice *bus)
369 {
370 	struct mvebu_spi_platdata *plat = dev_get_platdata(bus);
371 
372 	plat->spireg = (struct kwspi_registers *)devfdt_get_addr(bus);
373 
374 	return 0;
375 }
376 
377 static const struct dm_spi_ops mvebu_spi_ops = {
378 	.claim_bus	= mvebu_spi_claim_bus,
379 	.xfer		= mvebu_spi_xfer,
380 	.set_speed	= mvebu_spi_set_speed,
381 	.set_mode	= mvebu_spi_set_mode,
382 	/*
383 	 * cs_info is not needed, since we require all chip selects to be
384 	 * in the device tree explicitly
385 	 */
386 };
387 
388 static const struct mvebu_spi_dev armada_xp_spi_dev_data = {
389 	.is_errata_50mhz_ac = false,
390 };
391 
392 static const struct mvebu_spi_dev armada_375_spi_dev_data = {
393 	.is_errata_50mhz_ac = false,
394 };
395 
396 static const struct mvebu_spi_dev armada_380_spi_dev_data = {
397 	.is_errata_50mhz_ac = true,
398 };
399 
400 static const struct udevice_id mvebu_spi_ids[] = {
401 	{
402 		.compatible = "marvell,armada-375-spi",
403 		.data = (ulong)&armada_375_spi_dev_data
404 	},
405 	{
406 		.compatible = "marvell,armada-380-spi",
407 		.data = (ulong)&armada_380_spi_dev_data
408 	},
409 	{
410 		.compatible = "marvell,armada-xp-spi",
411 		.data = (ulong)&armada_xp_spi_dev_data
412 	},
413 	{ }
414 };
415 
416 U_BOOT_DRIVER(mvebu_spi) = {
417 	.name = "mvebu_spi",
418 	.id = UCLASS_SPI,
419 	.of_match = mvebu_spi_ids,
420 	.ops = &mvebu_spi_ops,
421 	.ofdata_to_platdata = mvebu_spi_ofdata_to_platdata,
422 	.platdata_auto_alloc_size = sizeof(struct mvebu_spi_platdata),
423 	.priv_auto_alloc_size = sizeof(struct mvebu_spi_priv),
424 	.probe = mvebu_spi_probe,
425 };
426 #endif
427