1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * SPI NOR driver for NXP SPI Flash Interface (SPIFI)
4 *
5 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
6 *
7 * Based on Freescale QuadSPI driver:
8 * Copyright (C) 2013 Freescale Semiconductor, Inc.
9 */
10
11 #include <linux/clk.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/iopoll.h>
15 #include <linux/module.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/partitions.h>
18 #include <linux/mtd/spi-nor.h>
19 #include <linux/of.h>
20 #include <linux/of_device.h>
21 #include <linux/platform_device.h>
22 #include <linux/spi/spi.h>
23
24 /* NXP SPIFI registers, bits and macros */
25 #define SPIFI_CTRL 0x000
26 #define SPIFI_CTRL_TIMEOUT(timeout) (timeout)
27 #define SPIFI_CTRL_CSHIGH(cshigh) ((cshigh) << 16)
28 #define SPIFI_CTRL_MODE3 BIT(23)
29 #define SPIFI_CTRL_DUAL BIT(28)
30 #define SPIFI_CTRL_FBCLK BIT(30)
31 #define SPIFI_CMD 0x004
32 #define SPIFI_CMD_DATALEN(dlen) ((dlen) & 0x3fff)
33 #define SPIFI_CMD_DOUT BIT(15)
34 #define SPIFI_CMD_INTLEN(ilen) ((ilen) << 16)
35 #define SPIFI_CMD_FIELDFORM(field) ((field) << 19)
36 #define SPIFI_CMD_FIELDFORM_ALL_SERIAL SPIFI_CMD_FIELDFORM(0x0)
37 #define SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA SPIFI_CMD_FIELDFORM(0x1)
38 #define SPIFI_CMD_FRAMEFORM(frame) ((frame) << 21)
39 #define SPIFI_CMD_FRAMEFORM_OPCODE_ONLY SPIFI_CMD_FRAMEFORM(0x1)
40 #define SPIFI_CMD_OPCODE(op) ((op) << 24)
41 #define SPIFI_ADDR 0x008
42 #define SPIFI_IDATA 0x00c
43 #define SPIFI_CLIMIT 0x010
44 #define SPIFI_DATA 0x014
45 #define SPIFI_MCMD 0x018
46 #define SPIFI_STAT 0x01c
47 #define SPIFI_STAT_MCINIT BIT(0)
48 #define SPIFI_STAT_CMD BIT(1)
49 #define SPIFI_STAT_RESET BIT(4)
50
51 #define SPI_NOR_MAX_ID_LEN 6
52
53 struct nxp_spifi {
54 struct device *dev;
55 struct clk *clk_spifi;
56 struct clk *clk_reg;
57 void __iomem *io_base;
58 void __iomem *flash_base;
59 struct spi_nor nor;
60 bool memory_mode;
61 u32 mcmd;
62 };
63
nxp_spifi_wait_for_cmd(struct nxp_spifi * spifi)64 static int nxp_spifi_wait_for_cmd(struct nxp_spifi *spifi)
65 {
66 u8 stat;
67 int ret;
68
69 ret = readb_poll_timeout(spifi->io_base + SPIFI_STAT, stat,
70 !(stat & SPIFI_STAT_CMD), 10, 30);
71 if (ret)
72 dev_warn(spifi->dev, "command timed out\n");
73
74 return ret;
75 }
76
nxp_spifi_reset(struct nxp_spifi * spifi)77 static int nxp_spifi_reset(struct nxp_spifi *spifi)
78 {
79 u8 stat;
80 int ret;
81
82 writel(SPIFI_STAT_RESET, spifi->io_base + SPIFI_STAT);
83 ret = readb_poll_timeout(spifi->io_base + SPIFI_STAT, stat,
84 !(stat & SPIFI_STAT_RESET), 10, 30);
85 if (ret)
86 dev_warn(spifi->dev, "state reset timed out\n");
87
88 return ret;
89 }
90
nxp_spifi_set_memory_mode_off(struct nxp_spifi * spifi)91 static int nxp_spifi_set_memory_mode_off(struct nxp_spifi *spifi)
92 {
93 int ret;
94
95 if (!spifi->memory_mode)
96 return 0;
97
98 ret = nxp_spifi_reset(spifi);
99 if (ret)
100 dev_err(spifi->dev, "unable to enter command mode\n");
101 else
102 spifi->memory_mode = false;
103
104 return ret;
105 }
106
nxp_spifi_set_memory_mode_on(struct nxp_spifi * spifi)107 static int nxp_spifi_set_memory_mode_on(struct nxp_spifi *spifi)
108 {
109 u8 stat;
110 int ret;
111
112 if (spifi->memory_mode)
113 return 0;
114
115 writel(spifi->mcmd, spifi->io_base + SPIFI_MCMD);
116 ret = readb_poll_timeout(spifi->io_base + SPIFI_STAT, stat,
117 stat & SPIFI_STAT_MCINIT, 10, 30);
118 if (ret)
119 dev_err(spifi->dev, "unable to enter memory mode\n");
120 else
121 spifi->memory_mode = true;
122
123 return ret;
124 }
125
nxp_spifi_read_reg(struct spi_nor * nor,u8 opcode,u8 * buf,size_t len)126 static int nxp_spifi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
127 size_t len)
128 {
129 struct nxp_spifi *spifi = nor->priv;
130 u32 cmd;
131 int ret;
132
133 ret = nxp_spifi_set_memory_mode_off(spifi);
134 if (ret)
135 return ret;
136
137 cmd = SPIFI_CMD_DATALEN(len) |
138 SPIFI_CMD_OPCODE(opcode) |
139 SPIFI_CMD_FIELDFORM_ALL_SERIAL |
140 SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
141 writel(cmd, spifi->io_base + SPIFI_CMD);
142
143 while (len--)
144 *buf++ = readb(spifi->io_base + SPIFI_DATA);
145
146 return nxp_spifi_wait_for_cmd(spifi);
147 }
148
nxp_spifi_write_reg(struct spi_nor * nor,u8 opcode,const u8 * buf,size_t len)149 static int nxp_spifi_write_reg(struct spi_nor *nor, u8 opcode, const u8 *buf,
150 size_t len)
151 {
152 struct nxp_spifi *spifi = nor->priv;
153 u32 cmd;
154 int ret;
155
156 ret = nxp_spifi_set_memory_mode_off(spifi);
157 if (ret)
158 return ret;
159
160 cmd = SPIFI_CMD_DOUT |
161 SPIFI_CMD_DATALEN(len) |
162 SPIFI_CMD_OPCODE(opcode) |
163 SPIFI_CMD_FIELDFORM_ALL_SERIAL |
164 SPIFI_CMD_FRAMEFORM_OPCODE_ONLY;
165 writel(cmd, spifi->io_base + SPIFI_CMD);
166
167 while (len--)
168 writeb(*buf++, spifi->io_base + SPIFI_DATA);
169
170 return nxp_spifi_wait_for_cmd(spifi);
171 }
172
nxp_spifi_read(struct spi_nor * nor,loff_t from,size_t len,u_char * buf)173 static ssize_t nxp_spifi_read(struct spi_nor *nor, loff_t from, size_t len,
174 u_char *buf)
175 {
176 struct nxp_spifi *spifi = nor->priv;
177 int ret;
178
179 ret = nxp_spifi_set_memory_mode_on(spifi);
180 if (ret)
181 return ret;
182
183 memcpy_fromio(buf, spifi->flash_base + from, len);
184
185 return len;
186 }
187
nxp_spifi_write(struct spi_nor * nor,loff_t to,size_t len,const u_char * buf)188 static ssize_t nxp_spifi_write(struct spi_nor *nor, loff_t to, size_t len,
189 const u_char *buf)
190 {
191 struct nxp_spifi *spifi = nor->priv;
192 u32 cmd;
193 int ret;
194 size_t i;
195
196 ret = nxp_spifi_set_memory_mode_off(spifi);
197 if (ret)
198 return ret;
199
200 writel(to, spifi->io_base + SPIFI_ADDR);
201
202 cmd = SPIFI_CMD_DOUT |
203 SPIFI_CMD_DATALEN(len) |
204 SPIFI_CMD_FIELDFORM_ALL_SERIAL |
205 SPIFI_CMD_OPCODE(nor->program_opcode) |
206 SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
207 writel(cmd, spifi->io_base + SPIFI_CMD);
208
209 for (i = 0; i < len; i++)
210 writeb(buf[i], spifi->io_base + SPIFI_DATA);
211
212 ret = nxp_spifi_wait_for_cmd(spifi);
213 if (ret)
214 return ret;
215
216 return len;
217 }
218
nxp_spifi_erase(struct spi_nor * nor,loff_t offs)219 static int nxp_spifi_erase(struct spi_nor *nor, loff_t offs)
220 {
221 struct nxp_spifi *spifi = nor->priv;
222 u32 cmd;
223 int ret;
224
225 ret = nxp_spifi_set_memory_mode_off(spifi);
226 if (ret)
227 return ret;
228
229 writel(offs, spifi->io_base + SPIFI_ADDR);
230
231 cmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL |
232 SPIFI_CMD_OPCODE(nor->erase_opcode) |
233 SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
234 writel(cmd, spifi->io_base + SPIFI_CMD);
235
236 return nxp_spifi_wait_for_cmd(spifi);
237 }
238
nxp_spifi_setup_memory_cmd(struct nxp_spifi * spifi)239 static int nxp_spifi_setup_memory_cmd(struct nxp_spifi *spifi)
240 {
241 switch (spifi->nor.read_proto) {
242 case SNOR_PROTO_1_1_1:
243 spifi->mcmd = SPIFI_CMD_FIELDFORM_ALL_SERIAL;
244 break;
245 case SNOR_PROTO_1_1_2:
246 case SNOR_PROTO_1_1_4:
247 spifi->mcmd = SPIFI_CMD_FIELDFORM_QUAD_DUAL_DATA;
248 break;
249 default:
250 dev_err(spifi->dev, "unsupported SPI read mode\n");
251 return -EINVAL;
252 }
253
254 /* Memory mode supports address length between 1 and 4 */
255 if (spifi->nor.addr_width < 1 || spifi->nor.addr_width > 4)
256 return -EINVAL;
257
258 spifi->mcmd |= SPIFI_CMD_OPCODE(spifi->nor.read_opcode) |
259 SPIFI_CMD_INTLEN(spifi->nor.read_dummy / 8) |
260 SPIFI_CMD_FRAMEFORM(spifi->nor.addr_width + 1);
261
262 return 0;
263 }
264
nxp_spifi_dummy_id_read(struct spi_nor * nor)265 static void nxp_spifi_dummy_id_read(struct spi_nor *nor)
266 {
267 u8 id[SPI_NOR_MAX_ID_LEN];
268 nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
269 SPI_NOR_MAX_ID_LEN);
270 }
271
272 static const struct spi_nor_controller_ops nxp_spifi_controller_ops = {
273 .read_reg = nxp_spifi_read_reg,
274 .write_reg = nxp_spifi_write_reg,
275 .read = nxp_spifi_read,
276 .write = nxp_spifi_write,
277 .erase = nxp_spifi_erase,
278 };
279
nxp_spifi_setup_flash(struct nxp_spifi * spifi,struct device_node * np)280 static int nxp_spifi_setup_flash(struct nxp_spifi *spifi,
281 struct device_node *np)
282 {
283 struct spi_nor_hwcaps hwcaps = {
284 .mask = SNOR_HWCAPS_READ |
285 SNOR_HWCAPS_READ_FAST |
286 SNOR_HWCAPS_PP,
287 };
288 u32 ctrl, property;
289 u16 mode = 0;
290 int ret;
291
292 if (!of_property_read_u32(np, "spi-rx-bus-width", &property)) {
293 switch (property) {
294 case 1:
295 break;
296 case 2:
297 mode |= SPI_RX_DUAL;
298 break;
299 case 4:
300 mode |= SPI_RX_QUAD;
301 break;
302 default:
303 dev_err(spifi->dev, "unsupported rx-bus-width\n");
304 return -EINVAL;
305 }
306 }
307
308 if (of_find_property(np, "spi-cpha", NULL))
309 mode |= SPI_CPHA;
310
311 if (of_find_property(np, "spi-cpol", NULL))
312 mode |= SPI_CPOL;
313
314 /* Setup control register defaults */
315 ctrl = SPIFI_CTRL_TIMEOUT(1000) |
316 SPIFI_CTRL_CSHIGH(15) |
317 SPIFI_CTRL_FBCLK;
318
319 if (mode & SPI_RX_DUAL) {
320 ctrl |= SPIFI_CTRL_DUAL;
321 hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
322 } else if (mode & SPI_RX_QUAD) {
323 ctrl &= ~SPIFI_CTRL_DUAL;
324 hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
325 } else {
326 ctrl |= SPIFI_CTRL_DUAL;
327 }
328
329 switch (mode & (SPI_CPHA | SPI_CPOL)) {
330 case SPI_MODE_0:
331 ctrl &= ~SPIFI_CTRL_MODE3;
332 break;
333 case SPI_MODE_3:
334 ctrl |= SPIFI_CTRL_MODE3;
335 break;
336 default:
337 dev_err(spifi->dev, "only mode 0 and 3 supported\n");
338 return -EINVAL;
339 }
340
341 writel(ctrl, spifi->io_base + SPIFI_CTRL);
342
343 spifi->nor.dev = spifi->dev;
344 spi_nor_set_flash_node(&spifi->nor, np);
345 spifi->nor.priv = spifi;
346 spifi->nor.controller_ops = &nxp_spifi_controller_ops;
347
348 /*
349 * The first read on a hard reset isn't reliable so do a
350 * dummy read of the id before calling spi_nor_scan().
351 * The reason for this problem is unknown.
352 *
353 * The official NXP spifilib uses more or less the same
354 * workaround that is applied here by reading the device
355 * id multiple times.
356 */
357 nxp_spifi_dummy_id_read(&spifi->nor);
358
359 ret = spi_nor_scan(&spifi->nor, NULL, &hwcaps);
360 if (ret) {
361 dev_err(spifi->dev, "device scan failed\n");
362 return ret;
363 }
364
365 ret = nxp_spifi_setup_memory_cmd(spifi);
366 if (ret) {
367 dev_err(spifi->dev, "memory command setup failed\n");
368 return ret;
369 }
370
371 ret = mtd_device_register(&spifi->nor.mtd, NULL, 0);
372 if (ret) {
373 dev_err(spifi->dev, "mtd device parse failed\n");
374 return ret;
375 }
376
377 return 0;
378 }
379
nxp_spifi_probe(struct platform_device * pdev)380 static int nxp_spifi_probe(struct platform_device *pdev)
381 {
382 struct device_node *flash_np;
383 struct nxp_spifi *spifi;
384 struct resource *res;
385 int ret;
386
387 spifi = devm_kzalloc(&pdev->dev, sizeof(*spifi), GFP_KERNEL);
388 if (!spifi)
389 return -ENOMEM;
390
391 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "spifi");
392 spifi->io_base = devm_ioremap_resource(&pdev->dev, res);
393 if (IS_ERR(spifi->io_base))
394 return PTR_ERR(spifi->io_base);
395
396 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "flash");
397 spifi->flash_base = devm_ioremap_resource(&pdev->dev, res);
398 if (IS_ERR(spifi->flash_base))
399 return PTR_ERR(spifi->flash_base);
400
401 spifi->clk_spifi = devm_clk_get(&pdev->dev, "spifi");
402 if (IS_ERR(spifi->clk_spifi)) {
403 dev_err(&pdev->dev, "spifi clock not found\n");
404 return PTR_ERR(spifi->clk_spifi);
405 }
406
407 spifi->clk_reg = devm_clk_get(&pdev->dev, "reg");
408 if (IS_ERR(spifi->clk_reg)) {
409 dev_err(&pdev->dev, "reg clock not found\n");
410 return PTR_ERR(spifi->clk_reg);
411 }
412
413 ret = clk_prepare_enable(spifi->clk_reg);
414 if (ret) {
415 dev_err(&pdev->dev, "unable to enable reg clock\n");
416 return ret;
417 }
418
419 ret = clk_prepare_enable(spifi->clk_spifi);
420 if (ret) {
421 dev_err(&pdev->dev, "unable to enable spifi clock\n");
422 goto dis_clk_reg;
423 }
424
425 spifi->dev = &pdev->dev;
426 platform_set_drvdata(pdev, spifi);
427
428 /* Initialize and reset device */
429 nxp_spifi_reset(spifi);
430 writel(0, spifi->io_base + SPIFI_IDATA);
431 writel(0, spifi->io_base + SPIFI_MCMD);
432 nxp_spifi_reset(spifi);
433
434 flash_np = of_get_next_available_child(pdev->dev.of_node, NULL);
435 if (!flash_np) {
436 dev_err(&pdev->dev, "no SPI flash device to configure\n");
437 ret = -ENODEV;
438 goto dis_clks;
439 }
440
441 ret = nxp_spifi_setup_flash(spifi, flash_np);
442 of_node_put(flash_np);
443 if (ret) {
444 dev_err(&pdev->dev, "unable to setup flash chip\n");
445 goto dis_clks;
446 }
447
448 return 0;
449
450 dis_clks:
451 clk_disable_unprepare(spifi->clk_spifi);
452 dis_clk_reg:
453 clk_disable_unprepare(spifi->clk_reg);
454 return ret;
455 }
456
nxp_spifi_remove(struct platform_device * pdev)457 static int nxp_spifi_remove(struct platform_device *pdev)
458 {
459 struct nxp_spifi *spifi = platform_get_drvdata(pdev);
460
461 mtd_device_unregister(&spifi->nor.mtd);
462 clk_disable_unprepare(spifi->clk_spifi);
463 clk_disable_unprepare(spifi->clk_reg);
464
465 return 0;
466 }
467
468 static const struct of_device_id nxp_spifi_match[] = {
469 {.compatible = "nxp,lpc1773-spifi"},
470 { /* sentinel */ }
471 };
472 MODULE_DEVICE_TABLE(of, nxp_spifi_match);
473
474 static struct platform_driver nxp_spifi_driver = {
475 .probe = nxp_spifi_probe,
476 .remove = nxp_spifi_remove,
477 .driver = {
478 .name = "nxp-spifi",
479 .of_match_table = nxp_spifi_match,
480 },
481 };
482 module_platform_driver(nxp_spifi_driver);
483
484 MODULE_DESCRIPTION("NXP SPI Flash Interface driver");
485 MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
486 MODULE_LICENSE("GPL v2");
487