Loading...
1/*
2 * EBI driver for Atmel chips
3 * inspired by the fsl weim bus driver
4 *
5 * Copyright (C) 2013 Jean-Jacques Hiblot <jjhiblot@traphandler.com>
6 *
7 * This file is licensed under the terms of the GNU General Public
8 * License version 2. This program is licensed "as is" without any
9 * warranty of any kind, whether express or implied.
10 */
11
12#include <linux/clk.h>
13#include <linux/io.h>
14#include <linux/mfd/syscon.h>
15#include <linux/mfd/syscon/atmel-matrix.h>
16#include <linux/mfd/syscon/atmel-smc.h>
17#include <linux/init.h>
18#include <linux/of_device.h>
19#include <linux/regmap.h>
20
21struct atmel_ebi_dev_config {
22 int cs;
23 struct atmel_smc_cs_conf smcconf;
24};
25
26struct atmel_ebi;
27
28struct atmel_ebi_dev {
29 struct list_head node;
30 struct atmel_ebi *ebi;
31 u32 mode;
32 int numcs;
33 struct atmel_ebi_dev_config configs[];
34};
35
36struct atmel_ebi_caps {
37 unsigned int available_cs;
38 unsigned int ebi_csa_offs;
39 void (*get_config)(struct atmel_ebi_dev *ebid,
40 struct atmel_ebi_dev_config *conf);
41 int (*xlate_config)(struct atmel_ebi_dev *ebid,
42 struct device_node *configs_np,
43 struct atmel_ebi_dev_config *conf);
44 void (*apply_config)(struct atmel_ebi_dev *ebid,
45 struct atmel_ebi_dev_config *conf);
46};
47
48struct atmel_ebi {
49 struct clk *clk;
50 struct regmap *matrix;
51 struct {
52 struct regmap *regmap;
53 struct clk *clk;
54 const struct atmel_hsmc_reg_layout *layout;
55 } smc;
56
57 struct device *dev;
58 const struct atmel_ebi_caps *caps;
59 struct list_head devs;
60};
61
62struct atmel_smc_timing_xlate {
63 const char *name;
64 int (*converter)(struct atmel_smc_cs_conf *conf,
65 unsigned int shift, unsigned int nycles);
66 unsigned int shift;
67};
68
69#define ATMEL_SMC_SETUP_XLATE(nm, pos) \
70 { .name = nm, .converter = atmel_smc_cs_conf_set_setup, .shift = pos}
71
72#define ATMEL_SMC_PULSE_XLATE(nm, pos) \
73 { .name = nm, .converter = atmel_smc_cs_conf_set_pulse, .shift = pos}
74
75#define ATMEL_SMC_CYCLE_XLATE(nm, pos) \
76 { .name = nm, .converter = atmel_smc_cs_conf_set_cycle, .shift = pos}
77
78static void at91sam9_ebi_get_config(struct atmel_ebi_dev *ebid,
79 struct atmel_ebi_dev_config *conf)
80{
81 atmel_smc_cs_conf_get(ebid->ebi->smc.regmap, conf->cs,
82 &conf->smcconf);
83}
84
85static void sama5_ebi_get_config(struct atmel_ebi_dev *ebid,
86 struct atmel_ebi_dev_config *conf)
87{
88 atmel_hsmc_cs_conf_get(ebid->ebi->smc.regmap, ebid->ebi->smc.layout,
89 conf->cs, &conf->smcconf);
90}
91
92static const struct atmel_smc_timing_xlate timings_xlate_table[] = {
93 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-rd-setup-ns",
94 ATMEL_SMC_NCS_RD_SHIFT),
95 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-wr-setup-ns",
96 ATMEL_SMC_NCS_WR_SHIFT),
97 ATMEL_SMC_SETUP_XLATE("atmel,smc-nrd-setup-ns", ATMEL_SMC_NRD_SHIFT),
98 ATMEL_SMC_SETUP_XLATE("atmel,smc-nwe-setup-ns", ATMEL_SMC_NWE_SHIFT),
99 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-rd-pulse-ns",
100 ATMEL_SMC_NCS_RD_SHIFT),
101 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-wr-pulse-ns",
102 ATMEL_SMC_NCS_WR_SHIFT),
103 ATMEL_SMC_PULSE_XLATE("atmel,smc-nrd-pulse-ns", ATMEL_SMC_NRD_SHIFT),
104 ATMEL_SMC_PULSE_XLATE("atmel,smc-nwe-pulse-ns", ATMEL_SMC_NWE_SHIFT),
105 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nrd-cycle-ns", ATMEL_SMC_NRD_SHIFT),
106 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nwe-cycle-ns", ATMEL_SMC_NWE_SHIFT),
107};
108
109static int atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev *ebid,
110 struct device_node *np,
111 struct atmel_smc_cs_conf *smcconf)
112{
113 unsigned int clk_rate = clk_get_rate(ebid->ebi->clk);
114 unsigned int clk_period_ns = NSEC_PER_SEC / clk_rate;
115 bool required = false;
116 unsigned int ncycles;
117 int ret, i;
118 u32 val;
119
120 ret = of_property_read_u32(np, "atmel,smc-tdf-ns", &val);
121 if (!ret) {
122 required = true;
123 ncycles = DIV_ROUND_UP(val, clk_period_ns);
124 if (ncycles > ATMEL_SMC_MODE_TDF_MAX) {
125 ret = -EINVAL;
126 goto out;
127 }
128
129 if (ncycles < ATMEL_SMC_MODE_TDF_MIN)
130 ncycles = ATMEL_SMC_MODE_TDF_MIN;
131
132 smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles);
133 }
134
135 for (i = 0; i < ARRAY_SIZE(timings_xlate_table); i++) {
136 const struct atmel_smc_timing_xlate *xlate;
137
138 xlate = &timings_xlate_table[i];
139
140 ret = of_property_read_u32(np, xlate->name, &val);
141 if (ret) {
142 if (!required)
143 continue;
144 else
145 break;
146 }
147
148 if (!required) {
149 ret = -EINVAL;
150 break;
151 }
152
153 ncycles = DIV_ROUND_UP(val, clk_period_ns);
154 ret = xlate->converter(smcconf, xlate->shift, ncycles);
155 if (ret)
156 goto out;
157 }
158
159out:
160 if (ret) {
161 dev_err(ebid->ebi->dev,
162 "missing or invalid timings definition in %pOF",
163 np);
164 return ret;
165 }
166
167 return required;
168}
169
170static int atmel_ebi_xslate_smc_config(struct atmel_ebi_dev *ebid,
171 struct device_node *np,
172 struct atmel_ebi_dev_config *conf)
173{
174 struct atmel_smc_cs_conf *smcconf = &conf->smcconf;
175 bool required = false;
176 const char *tmp_str;
177 u32 tmp;
178 int ret;
179
180 ret = of_property_read_u32(np, "atmel,smc-bus-width", &tmp);
181 if (!ret) {
182 switch (tmp) {
183 case 8:
184 smcconf->mode |= ATMEL_SMC_MODE_DBW_8;
185 break;
186
187 case 16:
188 smcconf->mode |= ATMEL_SMC_MODE_DBW_16;
189 break;
190
191 case 32:
192 smcconf->mode |= ATMEL_SMC_MODE_DBW_32;
193 break;
194
195 default:
196 return -EINVAL;
197 }
198
199 required = true;
200 }
201
202 if (of_property_read_bool(np, "atmel,smc-tdf-optimized")) {
203 smcconf->mode |= ATMEL_SMC_MODE_TDFMODE_OPTIMIZED;
204 required = true;
205 }
206
207 tmp_str = NULL;
208 of_property_read_string(np, "atmel,smc-byte-access-type", &tmp_str);
209 if (tmp_str && !strcmp(tmp_str, "write")) {
210 smcconf->mode |= ATMEL_SMC_MODE_BAT_WRITE;
211 required = true;
212 }
213
214 tmp_str = NULL;
215 of_property_read_string(np, "atmel,smc-read-mode", &tmp_str);
216 if (tmp_str && !strcmp(tmp_str, "nrd")) {
217 smcconf->mode |= ATMEL_SMC_MODE_READMODE_NRD;
218 required = true;
219 }
220
221 tmp_str = NULL;
222 of_property_read_string(np, "atmel,smc-write-mode", &tmp_str);
223 if (tmp_str && !strcmp(tmp_str, "nwe")) {
224 smcconf->mode |= ATMEL_SMC_MODE_WRITEMODE_NWE;
225 required = true;
226 }
227
228 tmp_str = NULL;
229 of_property_read_string(np, "atmel,smc-exnw-mode", &tmp_str);
230 if (tmp_str) {
231 if (!strcmp(tmp_str, "frozen"))
232 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_FROZEN;
233 else if (!strcmp(tmp_str, "ready"))
234 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_READY;
235 else if (strcmp(tmp_str, "disabled"))
236 return -EINVAL;
237
238 required = true;
239 }
240
241 ret = of_property_read_u32(np, "atmel,smc-page-mode", &tmp);
242 if (!ret) {
243 switch (tmp) {
244 case 4:
245 smcconf->mode |= ATMEL_SMC_MODE_PS_4;
246 break;
247
248 case 8:
249 smcconf->mode |= ATMEL_SMC_MODE_PS_8;
250 break;
251
252 case 16:
253 smcconf->mode |= ATMEL_SMC_MODE_PS_16;
254 break;
255
256 case 32:
257 smcconf->mode |= ATMEL_SMC_MODE_PS_32;
258 break;
259
260 default:
261 return -EINVAL;
262 }
263
264 smcconf->mode |= ATMEL_SMC_MODE_PMEN;
265 required = true;
266 }
267
268 ret = atmel_ebi_xslate_smc_timings(ebid, np, &conf->smcconf);
269 if (ret < 0)
270 return -EINVAL;
271
272 if ((ret > 0 && !required) || (!ret && required)) {
273 dev_err(ebid->ebi->dev, "missing atmel,smc- properties in %pOF",
274 np);
275 return -EINVAL;
276 }
277
278 return required;
279}
280
281static void at91sam9_ebi_apply_config(struct atmel_ebi_dev *ebid,
282 struct atmel_ebi_dev_config *conf)
283{
284 atmel_smc_cs_conf_apply(ebid->ebi->smc.regmap, conf->cs,
285 &conf->smcconf);
286}
287
288static void sama5_ebi_apply_config(struct atmel_ebi_dev *ebid,
289 struct atmel_ebi_dev_config *conf)
290{
291 atmel_hsmc_cs_conf_apply(ebid->ebi->smc.regmap, ebid->ebi->smc.layout,
292 conf->cs, &conf->smcconf);
293}
294
295static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
296 int reg_cells)
297{
298 const struct atmel_ebi_caps *caps = ebi->caps;
299 struct atmel_ebi_dev_config conf = { };
300 struct device *dev = ebi->dev;
301 struct atmel_ebi_dev *ebid;
302 unsigned long cslines = 0;
303 int ret, numcs = 0, nentries, i;
304 bool apply = false;
305 u32 cs;
306
307 nentries = of_property_count_elems_of_size(np, "reg",
308 reg_cells * sizeof(u32));
309 for (i = 0; i < nentries; i++) {
310 ret = of_property_read_u32_index(np, "reg", i * reg_cells,
311 &cs);
312 if (ret)
313 return ret;
314
315 if (cs >= AT91_MATRIX_EBI_NUM_CS ||
316 !(ebi->caps->available_cs & BIT(cs))) {
317 dev_err(dev, "invalid reg property in %pOF\n", np);
318 return -EINVAL;
319 }
320
321 if (!test_and_set_bit(cs, &cslines))
322 numcs++;
323 }
324
325 if (!numcs) {
326 dev_err(dev, "invalid reg property in %pOF\n", np);
327 return -EINVAL;
328 }
329
330 ebid = devm_kzalloc(ebi->dev,
331 sizeof(*ebid) + (numcs * sizeof(*ebid->configs)),
332 GFP_KERNEL);
333 if (!ebid)
334 return -ENOMEM;
335
336 ebid->ebi = ebi;
337 ebid->numcs = numcs;
338
339 ret = caps->xlate_config(ebid, np, &conf);
340 if (ret < 0)
341 return ret;
342 else if (ret)
343 apply = true;
344
345 i = 0;
346 for_each_set_bit(cs, &cslines, AT91_MATRIX_EBI_NUM_CS) {
347 ebid->configs[i].cs = cs;
348
349 if (apply) {
350 conf.cs = cs;
351 caps->apply_config(ebid, &conf);
352 }
353
354 caps->get_config(ebid, &ebid->configs[i]);
355
356 /*
357 * Attach the EBI device to the generic SMC logic if at least
358 * one "atmel,smc-" property is present.
359 */
360 if (ebi->caps->ebi_csa_offs && apply)
361 regmap_update_bits(ebi->matrix,
362 ebi->caps->ebi_csa_offs,
363 BIT(cs), 0);
364
365 i++;
366 }
367
368 list_add_tail(&ebid->node, &ebi->devs);
369
370 return 0;
371}
372
373static const struct atmel_ebi_caps at91sam9260_ebi_caps = {
374 .available_cs = 0xff,
375 .ebi_csa_offs = AT91SAM9260_MATRIX_EBICSA,
376 .get_config = at91sam9_ebi_get_config,
377 .xlate_config = atmel_ebi_xslate_smc_config,
378 .apply_config = at91sam9_ebi_apply_config,
379};
380
381static const struct atmel_ebi_caps at91sam9261_ebi_caps = {
382 .available_cs = 0xff,
383 .ebi_csa_offs = AT91SAM9261_MATRIX_EBICSA,
384 .get_config = at91sam9_ebi_get_config,
385 .xlate_config = atmel_ebi_xslate_smc_config,
386 .apply_config = at91sam9_ebi_apply_config,
387};
388
389static const struct atmel_ebi_caps at91sam9263_ebi0_caps = {
390 .available_cs = 0x3f,
391 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI0CSA,
392 .get_config = at91sam9_ebi_get_config,
393 .xlate_config = atmel_ebi_xslate_smc_config,
394 .apply_config = at91sam9_ebi_apply_config,
395};
396
397static const struct atmel_ebi_caps at91sam9263_ebi1_caps = {
398 .available_cs = 0x7,
399 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI1CSA,
400 .get_config = at91sam9_ebi_get_config,
401 .xlate_config = atmel_ebi_xslate_smc_config,
402 .apply_config = at91sam9_ebi_apply_config,
403};
404
405static const struct atmel_ebi_caps at91sam9rl_ebi_caps = {
406 .available_cs = 0x3f,
407 .ebi_csa_offs = AT91SAM9RL_MATRIX_EBICSA,
408 .get_config = at91sam9_ebi_get_config,
409 .xlate_config = atmel_ebi_xslate_smc_config,
410 .apply_config = at91sam9_ebi_apply_config,
411};
412
413static const struct atmel_ebi_caps at91sam9g45_ebi_caps = {
414 .available_cs = 0x3f,
415 .ebi_csa_offs = AT91SAM9G45_MATRIX_EBICSA,
416 .get_config = at91sam9_ebi_get_config,
417 .xlate_config = atmel_ebi_xslate_smc_config,
418 .apply_config = at91sam9_ebi_apply_config,
419};
420
421static const struct atmel_ebi_caps at91sam9x5_ebi_caps = {
422 .available_cs = 0x3f,
423 .ebi_csa_offs = AT91SAM9X5_MATRIX_EBICSA,
424 .get_config = at91sam9_ebi_get_config,
425 .xlate_config = atmel_ebi_xslate_smc_config,
426 .apply_config = at91sam9_ebi_apply_config,
427};
428
429static const struct atmel_ebi_caps sama5d3_ebi_caps = {
430 .available_cs = 0xf,
431 .get_config = sama5_ebi_get_config,
432 .xlate_config = atmel_ebi_xslate_smc_config,
433 .apply_config = sama5_ebi_apply_config,
434};
435
436static const struct of_device_id atmel_ebi_id_table[] = {
437 {
438 .compatible = "atmel,at91sam9260-ebi",
439 .data = &at91sam9260_ebi_caps,
440 },
441 {
442 .compatible = "atmel,at91sam9261-ebi",
443 .data = &at91sam9261_ebi_caps,
444 },
445 {
446 .compatible = "atmel,at91sam9263-ebi0",
447 .data = &at91sam9263_ebi0_caps,
448 },
449 {
450 .compatible = "atmel,at91sam9263-ebi1",
451 .data = &at91sam9263_ebi1_caps,
452 },
453 {
454 .compatible = "atmel,at91sam9rl-ebi",
455 .data = &at91sam9rl_ebi_caps,
456 },
457 {
458 .compatible = "atmel,at91sam9g45-ebi",
459 .data = &at91sam9g45_ebi_caps,
460 },
461 {
462 .compatible = "atmel,at91sam9x5-ebi",
463 .data = &at91sam9x5_ebi_caps,
464 },
465 {
466 .compatible = "atmel,sama5d3-ebi",
467 .data = &sama5d3_ebi_caps,
468 },
469 { /* sentinel */ }
470};
471
472static int atmel_ebi_dev_disable(struct atmel_ebi *ebi, struct device_node *np)
473{
474 struct device *dev = ebi->dev;
475 struct property *newprop;
476
477 newprop = devm_kzalloc(dev, sizeof(*newprop), GFP_KERNEL);
478 if (!newprop)
479 return -ENOMEM;
480
481 newprop->name = devm_kstrdup(dev, "status", GFP_KERNEL);
482 if (!newprop->name)
483 return -ENOMEM;
484
485 newprop->value = devm_kstrdup(dev, "disabled", GFP_KERNEL);
486 if (!newprop->value)
487 return -ENOMEM;
488
489 newprop->length = sizeof("disabled");
490
491 return of_update_property(np, newprop);
492}
493
494static int atmel_ebi_probe(struct platform_device *pdev)
495{
496 struct device *dev = &pdev->dev;
497 struct device_node *child, *np = dev->of_node, *smc_np;
498 const struct of_device_id *match;
499 struct atmel_ebi *ebi;
500 int ret, reg_cells;
501 struct clk *clk;
502 u32 val;
503
504 match = of_match_device(atmel_ebi_id_table, dev);
505 if (!match || !match->data)
506 return -EINVAL;
507
508 ebi = devm_kzalloc(dev, sizeof(*ebi), GFP_KERNEL);
509 if (!ebi)
510 return -ENOMEM;
511
512 platform_set_drvdata(pdev, ebi);
513
514 INIT_LIST_HEAD(&ebi->devs);
515 ebi->caps = match->data;
516 ebi->dev = dev;
517
518 clk = devm_clk_get(dev, NULL);
519 if (IS_ERR(clk))
520 return PTR_ERR(clk);
521
522 ebi->clk = clk;
523
524 smc_np = of_parse_phandle(dev->of_node, "atmel,smc", 0);
525
526 ebi->smc.regmap = syscon_node_to_regmap(smc_np);
527 if (IS_ERR(ebi->smc.regmap))
528 return PTR_ERR(ebi->smc.regmap);
529
530 ebi->smc.layout = atmel_hsmc_get_reg_layout(smc_np);
531 if (IS_ERR(ebi->smc.layout))
532 return PTR_ERR(ebi->smc.layout);
533
534 ebi->smc.clk = of_clk_get(smc_np, 0);
535 if (IS_ERR(ebi->smc.clk)) {
536 if (PTR_ERR(ebi->smc.clk) != -ENOENT)
537 return PTR_ERR(ebi->smc.clk);
538
539 ebi->smc.clk = NULL;
540 }
541 ret = clk_prepare_enable(ebi->smc.clk);
542 if (ret)
543 return ret;
544
545 /*
546 * The sama5d3 does not provide an EBICSA register and thus does need
547 * to access the matrix registers.
548 */
549 if (ebi->caps->ebi_csa_offs) {
550 ebi->matrix =
551 syscon_regmap_lookup_by_phandle(np, "atmel,matrix");
552 if (IS_ERR(ebi->matrix))
553 return PTR_ERR(ebi->matrix);
554 }
555
556 ret = of_property_read_u32(np, "#address-cells", &val);
557 if (ret) {
558 dev_err(dev, "missing #address-cells property\n");
559 return ret;
560 }
561
562 reg_cells = val;
563
564 ret = of_property_read_u32(np, "#size-cells", &val);
565 if (ret) {
566 dev_err(dev, "missing #address-cells property\n");
567 return ret;
568 }
569
570 reg_cells += val;
571
572 for_each_available_child_of_node(np, child) {
573 if (!of_find_property(child, "reg", NULL))
574 continue;
575
576 ret = atmel_ebi_dev_setup(ebi, child, reg_cells);
577 if (ret) {
578 dev_err(dev, "failed to configure EBI bus for %pOF, disabling the device",
579 child);
580
581 ret = atmel_ebi_dev_disable(ebi, child);
582 if (ret)
583 return ret;
584 }
585 }
586
587 return of_platform_populate(np, NULL, NULL, dev);
588}
589
590static __maybe_unused int atmel_ebi_resume(struct device *dev)
591{
592 struct atmel_ebi *ebi = dev_get_drvdata(dev);
593 struct atmel_ebi_dev *ebid;
594
595 list_for_each_entry(ebid, &ebi->devs, node) {
596 int i;
597
598 for (i = 0; i < ebid->numcs; i++)
599 ebid->ebi->caps->apply_config(ebid, &ebid->configs[i]);
600 }
601
602 return 0;
603}
604
605static SIMPLE_DEV_PM_OPS(atmel_ebi_pm_ops, NULL, atmel_ebi_resume);
606
607static struct platform_driver atmel_ebi_driver = {
608 .driver = {
609 .name = "atmel-ebi",
610 .of_match_table = atmel_ebi_id_table,
611 .pm = &atmel_ebi_pm_ops,
612 },
613};
614builtin_platform_driver_probe(atmel_ebi_driver, atmel_ebi_probe);