1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * EBI driver for Atmel chips
4 * inspired by the fsl weim bus driver
5 *
6 * Copyright (C) 2013 Jean-Jacques Hiblot <jjhiblot@traphandler.com>
7 */
8
9 #include <linux/cleanup.h>
10 #include <linux/clk.h>
11 #include <linux/io.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/mfd/syscon/atmel-matrix.h>
14 #include <linux/mfd/syscon/atmel-smc.h>
15 #include <linux/init.h>
16 #include <linux/of.h>
17 #include <linux/of_platform.h>
18 #include <linux/platform_device.h>
19 #include <linux/property.h>
20 #include <linux/regmap.h>
21 #include <soc/at91/atmel-sfr.h>
22
23 #define AT91_EBI_NUM_CS 8
24
25 struct atmel_ebi_dev_config {
26 int cs;
27 struct atmel_smc_cs_conf smcconf;
28 };
29
30 struct atmel_ebi;
31
32 struct atmel_ebi_dev {
33 struct list_head node;
34 struct atmel_ebi *ebi;
35 u32 mode;
36 int numcs;
37 struct atmel_ebi_dev_config configs[] __counted_by(numcs);
38 };
39
40 struct atmel_ebi_caps {
41 unsigned int available_cs;
42 unsigned int ebi_csa_offs;
43 const char *regmap_name;
44 void (*get_config)(struct atmel_ebi_dev *ebid,
45 struct atmel_ebi_dev_config *conf);
46 int (*xlate_config)(struct atmel_ebi_dev *ebid,
47 struct device_node *configs_np,
48 struct atmel_ebi_dev_config *conf);
49 void (*apply_config)(struct atmel_ebi_dev *ebid,
50 struct atmel_ebi_dev_config *conf);
51 };
52
53 struct atmel_ebi {
54 struct clk *clk;
55 struct regmap *regmap;
56 struct {
57 struct regmap *regmap;
58 struct clk *clk;
59 const struct atmel_hsmc_reg_layout *layout;
60 } smc;
61
62 struct device *dev;
63 const struct atmel_ebi_caps *caps;
64 struct list_head devs;
65 };
66
67 struct atmel_smc_timing_xlate {
68 const char *name;
69 int (*converter)(struct atmel_smc_cs_conf *conf,
70 unsigned int shift, unsigned int nycles);
71 unsigned int shift;
72 };
73
74 #define ATMEL_SMC_SETUP_XLATE(nm, pos) \
75 { .name = nm, .converter = atmel_smc_cs_conf_set_setup, .shift = pos}
76
77 #define ATMEL_SMC_PULSE_XLATE(nm, pos) \
78 { .name = nm, .converter = atmel_smc_cs_conf_set_pulse, .shift = pos}
79
80 #define ATMEL_SMC_CYCLE_XLATE(nm, pos) \
81 { .name = nm, .converter = atmel_smc_cs_conf_set_cycle, .shift = pos}
82
at91sam9_ebi_get_config(struct atmel_ebi_dev * ebid,struct atmel_ebi_dev_config * conf)83 static void at91sam9_ebi_get_config(struct atmel_ebi_dev *ebid,
84 struct atmel_ebi_dev_config *conf)
85 {
86 atmel_smc_cs_conf_get(ebid->ebi->smc.regmap, conf->cs,
87 &conf->smcconf);
88 }
89
sama5_ebi_get_config(struct atmel_ebi_dev * ebid,struct atmel_ebi_dev_config * conf)90 static void sama5_ebi_get_config(struct atmel_ebi_dev *ebid,
91 struct atmel_ebi_dev_config *conf)
92 {
93 atmel_hsmc_cs_conf_get(ebid->ebi->smc.regmap, ebid->ebi->smc.layout,
94 conf->cs, &conf->smcconf);
95 }
96
97 static const struct atmel_smc_timing_xlate timings_xlate_table[] = {
98 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-rd-setup-ns",
99 ATMEL_SMC_NCS_RD_SHIFT),
100 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-wr-setup-ns",
101 ATMEL_SMC_NCS_WR_SHIFT),
102 ATMEL_SMC_SETUP_XLATE("atmel,smc-nrd-setup-ns", ATMEL_SMC_NRD_SHIFT),
103 ATMEL_SMC_SETUP_XLATE("atmel,smc-nwe-setup-ns", ATMEL_SMC_NWE_SHIFT),
104 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-rd-pulse-ns",
105 ATMEL_SMC_NCS_RD_SHIFT),
106 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-wr-pulse-ns",
107 ATMEL_SMC_NCS_WR_SHIFT),
108 ATMEL_SMC_PULSE_XLATE("atmel,smc-nrd-pulse-ns", ATMEL_SMC_NRD_SHIFT),
109 ATMEL_SMC_PULSE_XLATE("atmel,smc-nwe-pulse-ns", ATMEL_SMC_NWE_SHIFT),
110 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nrd-cycle-ns", ATMEL_SMC_NRD_SHIFT),
111 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nwe-cycle-ns", ATMEL_SMC_NWE_SHIFT),
112 };
113
atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev * ebid,struct device_node * np,struct atmel_smc_cs_conf * smcconf)114 static int atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev *ebid,
115 struct device_node *np,
116 struct atmel_smc_cs_conf *smcconf)
117 {
118 unsigned int clk_rate = clk_get_rate(ebid->ebi->clk);
119 unsigned int clk_period_ns = NSEC_PER_SEC / clk_rate;
120 bool required = false;
121 unsigned int ncycles;
122 int ret, i;
123 u32 val;
124
125 ret = of_property_read_u32(np, "atmel,smc-tdf-ns", &val);
126 if (!ret) {
127 required = true;
128 ncycles = DIV_ROUND_UP(val, clk_period_ns);
129 if (ncycles > ATMEL_SMC_MODE_TDF_MAX) {
130 ret = -EINVAL;
131 goto out;
132 }
133
134 if (ncycles < ATMEL_SMC_MODE_TDF_MIN)
135 ncycles = ATMEL_SMC_MODE_TDF_MIN;
136
137 smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles);
138 }
139
140 for (i = 0; i < ARRAY_SIZE(timings_xlate_table); i++) {
141 const struct atmel_smc_timing_xlate *xlate;
142
143 xlate = &timings_xlate_table[i];
144
145 ret = of_property_read_u32(np, xlate->name, &val);
146 if (ret) {
147 if (!required)
148 continue;
149 else
150 break;
151 }
152
153 if (!required) {
154 ret = -EINVAL;
155 break;
156 }
157
158 ncycles = DIV_ROUND_UP(val, clk_period_ns);
159 ret = xlate->converter(smcconf, xlate->shift, ncycles);
160 if (ret)
161 goto out;
162 }
163
164 out:
165 if (ret) {
166 dev_err(ebid->ebi->dev,
167 "missing or invalid timings definition in %pOF",
168 np);
169 return ret;
170 }
171
172 return required;
173 }
174
atmel_ebi_xslate_smc_config(struct atmel_ebi_dev * ebid,struct device_node * np,struct atmel_ebi_dev_config * conf)175 static int atmel_ebi_xslate_smc_config(struct atmel_ebi_dev *ebid,
176 struct device_node *np,
177 struct atmel_ebi_dev_config *conf)
178 {
179 struct atmel_smc_cs_conf *smcconf = &conf->smcconf;
180 bool required = false;
181 const char *tmp_str;
182 u32 tmp;
183 int ret;
184
185 ret = of_property_read_u32(np, "atmel,smc-bus-width", &tmp);
186 if (!ret) {
187 switch (tmp) {
188 case 8:
189 smcconf->mode |= ATMEL_SMC_MODE_DBW_8;
190 break;
191
192 case 16:
193 smcconf->mode |= ATMEL_SMC_MODE_DBW_16;
194 break;
195
196 case 32:
197 smcconf->mode |= ATMEL_SMC_MODE_DBW_32;
198 break;
199
200 default:
201 return -EINVAL;
202 }
203
204 required = true;
205 }
206
207 if (of_property_read_bool(np, "atmel,smc-tdf-optimized")) {
208 smcconf->mode |= ATMEL_SMC_MODE_TDFMODE_OPTIMIZED;
209 required = true;
210 }
211
212 tmp_str = NULL;
213 of_property_read_string(np, "atmel,smc-byte-access-type", &tmp_str);
214 if (tmp_str && !strcmp(tmp_str, "write")) {
215 smcconf->mode |= ATMEL_SMC_MODE_BAT_WRITE;
216 required = true;
217 }
218
219 tmp_str = NULL;
220 of_property_read_string(np, "atmel,smc-read-mode", &tmp_str);
221 if (tmp_str && !strcmp(tmp_str, "nrd")) {
222 smcconf->mode |= ATMEL_SMC_MODE_READMODE_NRD;
223 required = true;
224 }
225
226 tmp_str = NULL;
227 of_property_read_string(np, "atmel,smc-write-mode", &tmp_str);
228 if (tmp_str && !strcmp(tmp_str, "nwe")) {
229 smcconf->mode |= ATMEL_SMC_MODE_WRITEMODE_NWE;
230 required = true;
231 }
232
233 tmp_str = NULL;
234 of_property_read_string(np, "atmel,smc-exnw-mode", &tmp_str);
235 if (tmp_str) {
236 if (!strcmp(tmp_str, "frozen"))
237 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_FROZEN;
238 else if (!strcmp(tmp_str, "ready"))
239 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_READY;
240 else if (strcmp(tmp_str, "disabled"))
241 return -EINVAL;
242
243 required = true;
244 }
245
246 ret = of_property_read_u32(np, "atmel,smc-page-mode", &tmp);
247 if (!ret) {
248 switch (tmp) {
249 case 4:
250 smcconf->mode |= ATMEL_SMC_MODE_PS_4;
251 break;
252
253 case 8:
254 smcconf->mode |= ATMEL_SMC_MODE_PS_8;
255 break;
256
257 case 16:
258 smcconf->mode |= ATMEL_SMC_MODE_PS_16;
259 break;
260
261 case 32:
262 smcconf->mode |= ATMEL_SMC_MODE_PS_32;
263 break;
264
265 default:
266 return -EINVAL;
267 }
268
269 smcconf->mode |= ATMEL_SMC_MODE_PMEN;
270 required = true;
271 }
272
273 ret = atmel_ebi_xslate_smc_timings(ebid, np, &conf->smcconf);
274 if (ret < 0)
275 return -EINVAL;
276
277 if ((ret > 0 && !required) || (!ret && required)) {
278 dev_err(ebid->ebi->dev, "missing atmel,smc- properties in %pOF",
279 np);
280 return -EINVAL;
281 }
282
283 return required;
284 }
285
at91sam9_ebi_apply_config(struct atmel_ebi_dev * ebid,struct atmel_ebi_dev_config * conf)286 static void at91sam9_ebi_apply_config(struct atmel_ebi_dev *ebid,
287 struct atmel_ebi_dev_config *conf)
288 {
289 atmel_smc_cs_conf_apply(ebid->ebi->smc.regmap, conf->cs,
290 &conf->smcconf);
291 }
292
sama5_ebi_apply_config(struct atmel_ebi_dev * ebid,struct atmel_ebi_dev_config * conf)293 static void sama5_ebi_apply_config(struct atmel_ebi_dev *ebid,
294 struct atmel_ebi_dev_config *conf)
295 {
296 atmel_hsmc_cs_conf_apply(ebid->ebi->smc.regmap, ebid->ebi->smc.layout,
297 conf->cs, &conf->smcconf);
298 }
299
atmel_ebi_dev_setup(struct atmel_ebi * ebi,struct device_node * np,int reg_cells)300 static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
301 int reg_cells)
302 {
303 const struct atmel_ebi_caps *caps = ebi->caps;
304 struct atmel_ebi_dev_config conf = { };
305 struct device *dev = ebi->dev;
306 struct atmel_ebi_dev *ebid;
307 unsigned long cslines = 0;
308 int ret, numcs = 0, nentries, i;
309 bool apply = false;
310 u32 cs;
311
312 nentries = of_property_count_elems_of_size(np, "reg",
313 reg_cells * sizeof(u32));
314 for (i = 0; i < nentries; i++) {
315 ret = of_property_read_u32_index(np, "reg", i * reg_cells,
316 &cs);
317 if (ret)
318 return ret;
319
320 if (cs >= AT91_EBI_NUM_CS ||
321 !(ebi->caps->available_cs & BIT(cs))) {
322 dev_err(dev, "invalid reg property in %pOF\n", np);
323 return -EINVAL;
324 }
325
326 if (!test_and_set_bit(cs, &cslines))
327 numcs++;
328 }
329
330 if (!numcs) {
331 dev_err(dev, "invalid reg property in %pOF\n", np);
332 return -EINVAL;
333 }
334
335 ebid = devm_kzalloc(ebi->dev, struct_size(ebid, configs, numcs),
336 GFP_KERNEL);
337 if (!ebid)
338 return -ENOMEM;
339
340 ebid->ebi = ebi;
341 ebid->numcs = numcs;
342
343 ret = caps->xlate_config(ebid, np, &conf);
344 if (ret < 0)
345 return ret;
346 else if (ret)
347 apply = true;
348
349 i = 0;
350 for_each_set_bit(cs, &cslines, AT91_EBI_NUM_CS) {
351 ebid->configs[i].cs = cs;
352
353 if (apply) {
354 conf.cs = cs;
355 caps->apply_config(ebid, &conf);
356 }
357
358 caps->get_config(ebid, &ebid->configs[i]);
359
360 /*
361 * Attach the EBI device to the generic SMC logic if at least
362 * one "atmel,smc-" property is present.
363 */
364 if (ebi->caps->ebi_csa_offs && apply)
365 regmap_update_bits(ebi->regmap,
366 ebi->caps->ebi_csa_offs,
367 BIT(cs), 0);
368
369 i++;
370 }
371
372 list_add_tail(&ebid->node, &ebi->devs);
373
374 return 0;
375 }
376
377 static const struct atmel_ebi_caps at91sam9260_ebi_caps = {
378 .available_cs = 0xff,
379 .ebi_csa_offs = AT91SAM9260_MATRIX_EBICSA,
380 .regmap_name = "atmel,matrix",
381 .get_config = at91sam9_ebi_get_config,
382 .xlate_config = atmel_ebi_xslate_smc_config,
383 .apply_config = at91sam9_ebi_apply_config,
384 };
385
386 static const struct atmel_ebi_caps at91sam9261_ebi_caps = {
387 .available_cs = 0xff,
388 .ebi_csa_offs = AT91SAM9261_MATRIX_EBICSA,
389 .regmap_name = "atmel,matrix",
390 .get_config = at91sam9_ebi_get_config,
391 .xlate_config = atmel_ebi_xslate_smc_config,
392 .apply_config = at91sam9_ebi_apply_config,
393 };
394
395 static const struct atmel_ebi_caps at91sam9263_ebi0_caps = {
396 .available_cs = 0x3f,
397 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI0CSA,
398 .regmap_name = "atmel,matrix",
399 .get_config = at91sam9_ebi_get_config,
400 .xlate_config = atmel_ebi_xslate_smc_config,
401 .apply_config = at91sam9_ebi_apply_config,
402 };
403
404 static const struct atmel_ebi_caps at91sam9263_ebi1_caps = {
405 .available_cs = 0x7,
406 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI1CSA,
407 .regmap_name = "atmel,matrix",
408 .get_config = at91sam9_ebi_get_config,
409 .xlate_config = atmel_ebi_xslate_smc_config,
410 .apply_config = at91sam9_ebi_apply_config,
411 };
412
413 static const struct atmel_ebi_caps at91sam9rl_ebi_caps = {
414 .available_cs = 0x3f,
415 .ebi_csa_offs = AT91SAM9RL_MATRIX_EBICSA,
416 .regmap_name = "atmel,matrix",
417 .get_config = at91sam9_ebi_get_config,
418 .xlate_config = atmel_ebi_xslate_smc_config,
419 .apply_config = at91sam9_ebi_apply_config,
420 };
421
422 static const struct atmel_ebi_caps at91sam9g45_ebi_caps = {
423 .available_cs = 0x3f,
424 .ebi_csa_offs = AT91SAM9G45_MATRIX_EBICSA,
425 .regmap_name = "atmel,matrix",
426 .get_config = at91sam9_ebi_get_config,
427 .xlate_config = atmel_ebi_xslate_smc_config,
428 .apply_config = at91sam9_ebi_apply_config,
429 };
430
431 static const struct atmel_ebi_caps at91sam9x5_ebi_caps = {
432 .available_cs = 0x3f,
433 .ebi_csa_offs = AT91SAM9X5_MATRIX_EBICSA,
434 .regmap_name = "atmel,matrix",
435 .get_config = at91sam9_ebi_get_config,
436 .xlate_config = atmel_ebi_xslate_smc_config,
437 .apply_config = at91sam9_ebi_apply_config,
438 };
439
440 static const struct atmel_ebi_caps sama5d3_ebi_caps = {
441 .available_cs = 0xf,
442 .get_config = sama5_ebi_get_config,
443 .xlate_config = atmel_ebi_xslate_smc_config,
444 .apply_config = sama5_ebi_apply_config,
445 };
446
447 static const struct atmel_ebi_caps sam9x60_ebi_caps = {
448 .available_cs = 0x3f,
449 .ebi_csa_offs = AT91_SFR_CCFG_EBICSA,
450 .regmap_name = "microchip,sfr",
451 .get_config = at91sam9_ebi_get_config,
452 .xlate_config = atmel_ebi_xslate_smc_config,
453 .apply_config = at91sam9_ebi_apply_config,
454 };
455
456 static const struct of_device_id atmel_ebi_id_table[] = {
457 {
458 .compatible = "atmel,at91sam9260-ebi",
459 .data = &at91sam9260_ebi_caps,
460 },
461 {
462 .compatible = "atmel,at91sam9261-ebi",
463 .data = &at91sam9261_ebi_caps,
464 },
465 {
466 .compatible = "atmel,at91sam9263-ebi0",
467 .data = &at91sam9263_ebi0_caps,
468 },
469 {
470 .compatible = "atmel,at91sam9263-ebi1",
471 .data = &at91sam9263_ebi1_caps,
472 },
473 {
474 .compatible = "atmel,at91sam9rl-ebi",
475 .data = &at91sam9rl_ebi_caps,
476 },
477 {
478 .compatible = "atmel,at91sam9g45-ebi",
479 .data = &at91sam9g45_ebi_caps,
480 },
481 {
482 .compatible = "atmel,at91sam9x5-ebi",
483 .data = &at91sam9x5_ebi_caps,
484 },
485 {
486 .compatible = "atmel,sama5d3-ebi",
487 .data = &sama5d3_ebi_caps,
488 },
489 {
490 .compatible = "microchip,sam9x60-ebi",
491 .data = &sam9x60_ebi_caps,
492 },
493 { /* sentinel */ }
494 };
495
atmel_ebi_dev_disable(struct atmel_ebi * ebi,struct device_node * np)496 static int atmel_ebi_dev_disable(struct atmel_ebi *ebi, struct device_node *np)
497 {
498 struct device *dev = ebi->dev;
499 struct property *newprop;
500
501 newprop = devm_kzalloc(dev, sizeof(*newprop), GFP_KERNEL);
502 if (!newprop)
503 return -ENOMEM;
504
505 newprop->name = devm_kstrdup(dev, "status", GFP_KERNEL);
506 if (!newprop->name)
507 return -ENOMEM;
508
509 newprop->value = devm_kstrdup(dev, "disabled", GFP_KERNEL);
510 if (!newprop->value)
511 return -ENOMEM;
512
513 newprop->length = sizeof("disabled");
514
515 return of_update_property(np, newprop);
516 }
517
atmel_ebi_probe(struct platform_device * pdev)518 static int atmel_ebi_probe(struct platform_device *pdev)
519 {
520 struct device *dev = &pdev->dev;
521 struct device_node *np = dev->of_node;
522 struct atmel_ebi *ebi;
523 int ret, reg_cells;
524 struct clk *clk;
525 u32 val;
526
527 ebi = devm_kzalloc(dev, sizeof(*ebi), GFP_KERNEL);
528 if (!ebi)
529 return -ENOMEM;
530
531 platform_set_drvdata(pdev, ebi);
532
533 INIT_LIST_HEAD(&ebi->devs);
534 ebi->caps = device_get_match_data(dev);
535 if (!ebi->caps)
536 return -EINVAL;
537 ebi->dev = dev;
538
539 clk = devm_clk_get(dev, NULL);
540 if (IS_ERR(clk))
541 return PTR_ERR(clk);
542
543 ebi->clk = clk;
544
545 struct device_node *smc_np __free(device_node) =
546 of_parse_phandle(dev->of_node, "atmel,smc", 0);
547
548 ebi->smc.regmap = syscon_node_to_regmap(smc_np);
549 if (IS_ERR(ebi->smc.regmap))
550 return PTR_ERR(ebi->smc.regmap);
551
552 ebi->smc.layout = atmel_hsmc_get_reg_layout(smc_np);
553 if (IS_ERR(ebi->smc.layout))
554 return PTR_ERR(ebi->smc.layout);
555
556 ebi->smc.clk = of_clk_get(smc_np, 0);
557 if (IS_ERR(ebi->smc.clk)) {
558 if (PTR_ERR(ebi->smc.clk) != -ENOENT)
559 return PTR_ERR(ebi->smc.clk);
560
561 ebi->smc.clk = NULL;
562 }
563 ret = clk_prepare_enable(ebi->smc.clk);
564 if (ret)
565 return ret;
566
567 /*
568 * The sama5d3 does not provide an EBICSA register and thus does need
569 * to access it.
570 */
571 if (ebi->caps->ebi_csa_offs) {
572 ebi->regmap =
573 syscon_regmap_lookup_by_phandle(np,
574 ebi->caps->regmap_name);
575 if (IS_ERR(ebi->regmap))
576 return PTR_ERR(ebi->regmap);
577 }
578
579 ret = of_property_read_u32(np, "#address-cells", &val);
580 if (ret) {
581 dev_err(dev, "missing #address-cells property\n");
582 return ret;
583 }
584
585 reg_cells = val;
586
587 ret = of_property_read_u32(np, "#size-cells", &val);
588 if (ret) {
589 dev_err(dev, "missing #address-cells property\n");
590 return ret;
591 }
592
593 reg_cells += val;
594
595 for_each_available_child_of_node_scoped(np, child) {
596 if (!of_property_present(child, "reg"))
597 continue;
598
599 ret = atmel_ebi_dev_setup(ebi, child, reg_cells);
600 if (ret) {
601 dev_err(dev, "failed to configure EBI bus for %pOF, disabling the device",
602 child);
603
604 ret = atmel_ebi_dev_disable(ebi, child);
605 if (ret)
606 return ret;
607 }
608 }
609
610 return of_platform_populate(np, NULL, NULL, dev);
611 }
612
atmel_ebi_resume(struct device * dev)613 static __maybe_unused int atmel_ebi_resume(struct device *dev)
614 {
615 struct atmel_ebi *ebi = dev_get_drvdata(dev);
616 struct atmel_ebi_dev *ebid;
617
618 list_for_each_entry(ebid, &ebi->devs, node) {
619 int i;
620
621 for (i = 0; i < ebid->numcs; i++)
622 ebid->ebi->caps->apply_config(ebid, &ebid->configs[i]);
623 }
624
625 return 0;
626 }
627
628 static SIMPLE_DEV_PM_OPS(atmel_ebi_pm_ops, NULL, atmel_ebi_resume);
629
630 static struct platform_driver atmel_ebi_driver = {
631 .driver = {
632 .name = "atmel-ebi",
633 .of_match_table = atmel_ebi_id_table,
634 .pm = &atmel_ebi_pm_ops,
635 },
636 };
637 builtin_platform_driver_probe(atmel_ebi_driver, atmel_ebi_probe);
638