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/clk.h>
10#include <linux/io.h>
11#include <linux/mfd/syscon.h>
12#include <linux/mfd/syscon/atmel-matrix.h>
13#include <linux/mfd/syscon/atmel-smc.h>
14#include <linux/init.h>
15#include <linux/of.h>
16#include <linux/of_platform.h>
17#include <linux/platform_device.h>
18#include <linux/property.h>
19#include <linux/regmap.h>
20#include <soc/at91/atmel-sfr.h>
21
22#define AT91_EBI_NUM_CS 8
23
24struct atmel_ebi_dev_config {
25 int cs;
26 struct atmel_smc_cs_conf smcconf;
27};
28
29struct atmel_ebi;
30
31struct atmel_ebi_dev {
32 struct list_head node;
33 struct atmel_ebi *ebi;
34 u32 mode;
35 int numcs;
36 struct atmel_ebi_dev_config configs[] __counted_by(numcs);
37};
38
39struct atmel_ebi_caps {
40 unsigned int available_cs;
41 unsigned int ebi_csa_offs;
42 const char *regmap_name;
43 void (*get_config)(struct atmel_ebi_dev *ebid,
44 struct atmel_ebi_dev_config *conf);
45 int (*xlate_config)(struct atmel_ebi_dev *ebid,
46 struct device_node *configs_np,
47 struct atmel_ebi_dev_config *conf);
48 void (*apply_config)(struct atmel_ebi_dev *ebid,
49 struct atmel_ebi_dev_config *conf);
50};
51
52struct atmel_ebi {
53 struct clk *clk;
54 struct regmap *regmap;
55 struct {
56 struct regmap *regmap;
57 struct clk *clk;
58 const struct atmel_hsmc_reg_layout *layout;
59 } smc;
60
61 struct device *dev;
62 const struct atmel_ebi_caps *caps;
63 struct list_head devs;
64};
65
66struct atmel_smc_timing_xlate {
67 const char *name;
68 int (*converter)(struct atmel_smc_cs_conf *conf,
69 unsigned int shift, unsigned int nycles);
70 unsigned int shift;
71};
72
73#define ATMEL_SMC_SETUP_XLATE(nm, pos) \
74 { .name = nm, .converter = atmel_smc_cs_conf_set_setup, .shift = pos}
75
76#define ATMEL_SMC_PULSE_XLATE(nm, pos) \
77 { .name = nm, .converter = atmel_smc_cs_conf_set_pulse, .shift = pos}
78
79#define ATMEL_SMC_CYCLE_XLATE(nm, pos) \
80 { .name = nm, .converter = atmel_smc_cs_conf_set_cycle, .shift = pos}
81
82static void at91sam9_ebi_get_config(struct atmel_ebi_dev *ebid,
83 struct atmel_ebi_dev_config *conf)
84{
85 atmel_smc_cs_conf_get(regmap: ebid->ebi->smc.regmap, cs: conf->cs,
86 conf: &conf->smcconf);
87}
88
89static void sama5_ebi_get_config(struct atmel_ebi_dev *ebid,
90 struct atmel_ebi_dev_config *conf)
91{
92 atmel_hsmc_cs_conf_get(regmap: ebid->ebi->smc.regmap, reglayout: ebid->ebi->smc.layout,
93 cs: conf->cs, conf: &conf->smcconf);
94}
95
96static const struct atmel_smc_timing_xlate timings_xlate_table[] = {
97 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-rd-setup-ns",
98 ATMEL_SMC_NCS_RD_SHIFT),
99 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-wr-setup-ns",
100 ATMEL_SMC_NCS_WR_SHIFT),
101 ATMEL_SMC_SETUP_XLATE("atmel,smc-nrd-setup-ns", ATMEL_SMC_NRD_SHIFT),
102 ATMEL_SMC_SETUP_XLATE("atmel,smc-nwe-setup-ns", ATMEL_SMC_NWE_SHIFT),
103 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-rd-pulse-ns",
104 ATMEL_SMC_NCS_RD_SHIFT),
105 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-wr-pulse-ns",
106 ATMEL_SMC_NCS_WR_SHIFT),
107 ATMEL_SMC_PULSE_XLATE("atmel,smc-nrd-pulse-ns", ATMEL_SMC_NRD_SHIFT),
108 ATMEL_SMC_PULSE_XLATE("atmel,smc-nwe-pulse-ns", ATMEL_SMC_NWE_SHIFT),
109 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nrd-cycle-ns", ATMEL_SMC_NRD_SHIFT),
110 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nwe-cycle-ns", ATMEL_SMC_NWE_SHIFT),
111};
112
113static int atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev *ebid,
114 struct device_node *np,
115 struct atmel_smc_cs_conf *smcconf)
116{
117 unsigned int clk_rate = clk_get_rate(clk: ebid->ebi->clk);
118 unsigned int clk_period_ns = NSEC_PER_SEC / clk_rate;
119 bool required = false;
120 unsigned int ncycles;
121 int ret, i;
122 u32 val;
123
124 ret = of_property_read_u32(np, propname: "atmel,smc-tdf-ns", out_value: &val);
125 if (!ret) {
126 required = true;
127 ncycles = DIV_ROUND_UP(val, clk_period_ns);
128 if (ncycles > ATMEL_SMC_MODE_TDF_MAX) {
129 ret = -EINVAL;
130 goto out;
131 }
132
133 if (ncycles < ATMEL_SMC_MODE_TDF_MIN)
134 ncycles = ATMEL_SMC_MODE_TDF_MIN;
135
136 smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles);
137 }
138
139 for (i = 0; i < ARRAY_SIZE(timings_xlate_table); i++) {
140 const struct atmel_smc_timing_xlate *xlate;
141
142 xlate = &timings_xlate_table[i];
143
144 ret = of_property_read_u32(np, propname: xlate->name, out_value: &val);
145 if (ret) {
146 if (!required)
147 continue;
148 else
149 break;
150 }
151
152 if (!required) {
153 ret = -EINVAL;
154 break;
155 }
156
157 ncycles = DIV_ROUND_UP(val, clk_period_ns);
158 ret = xlate->converter(smcconf, xlate->shift, ncycles);
159 if (ret)
160 goto out;
161 }
162
163out:
164 if (ret) {
165 dev_err(ebid->ebi->dev,
166 "missing or invalid timings definition in %pOF",
167 np);
168 return ret;
169 }
170
171 return required;
172}
173
174static int atmel_ebi_xslate_smc_config(struct atmel_ebi_dev *ebid,
175 struct device_node *np,
176 struct atmel_ebi_dev_config *conf)
177{
178 struct atmel_smc_cs_conf *smcconf = &conf->smcconf;
179 bool required = false;
180 const char *tmp_str;
181 u32 tmp;
182 int ret;
183
184 ret = of_property_read_u32(np, propname: "atmel,smc-bus-width", out_value: &tmp);
185 if (!ret) {
186 switch (tmp) {
187 case 8:
188 smcconf->mode |= ATMEL_SMC_MODE_DBW_8;
189 break;
190
191 case 16:
192 smcconf->mode |= ATMEL_SMC_MODE_DBW_16;
193 break;
194
195 case 32:
196 smcconf->mode |= ATMEL_SMC_MODE_DBW_32;
197 break;
198
199 default:
200 return -EINVAL;
201 }
202
203 required = true;
204 }
205
206 if (of_property_read_bool(np, propname: "atmel,smc-tdf-optimized")) {
207 smcconf->mode |= ATMEL_SMC_MODE_TDFMODE_OPTIMIZED;
208 required = true;
209 }
210
211 tmp_str = NULL;
212 of_property_read_string(np, propname: "atmel,smc-byte-access-type", out_string: &tmp_str);
213 if (tmp_str && !strcmp(tmp_str, "write")) {
214 smcconf->mode |= ATMEL_SMC_MODE_BAT_WRITE;
215 required = true;
216 }
217
218 tmp_str = NULL;
219 of_property_read_string(np, propname: "atmel,smc-read-mode", out_string: &tmp_str);
220 if (tmp_str && !strcmp(tmp_str, "nrd")) {
221 smcconf->mode |= ATMEL_SMC_MODE_READMODE_NRD;
222 required = true;
223 }
224
225 tmp_str = NULL;
226 of_property_read_string(np, propname: "atmel,smc-write-mode", out_string: &tmp_str);
227 if (tmp_str && !strcmp(tmp_str, "nwe")) {
228 smcconf->mode |= ATMEL_SMC_MODE_WRITEMODE_NWE;
229 required = true;
230 }
231
232 tmp_str = NULL;
233 of_property_read_string(np, propname: "atmel,smc-exnw-mode", out_string: &tmp_str);
234 if (tmp_str) {
235 if (!strcmp(tmp_str, "frozen"))
236 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_FROZEN;
237 else if (!strcmp(tmp_str, "ready"))
238 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_READY;
239 else if (strcmp(tmp_str, "disabled"))
240 return -EINVAL;
241
242 required = true;
243 }
244
245 ret = of_property_read_u32(np, propname: "atmel,smc-page-mode", out_value: &tmp);
246 if (!ret) {
247 switch (tmp) {
248 case 4:
249 smcconf->mode |= ATMEL_SMC_MODE_PS_4;
250 break;
251
252 case 8:
253 smcconf->mode |= ATMEL_SMC_MODE_PS_8;
254 break;
255
256 case 16:
257 smcconf->mode |= ATMEL_SMC_MODE_PS_16;
258 break;
259
260 case 32:
261 smcconf->mode |= ATMEL_SMC_MODE_PS_32;
262 break;
263
264 default:
265 return -EINVAL;
266 }
267
268 smcconf->mode |= ATMEL_SMC_MODE_PMEN;
269 required = true;
270 }
271
272 ret = atmel_ebi_xslate_smc_timings(ebid, np, smcconf: &conf->smcconf);
273 if (ret < 0)
274 return -EINVAL;
275
276 if ((ret > 0 && !required) || (!ret && required)) {
277 dev_err(ebid->ebi->dev, "missing atmel,smc- properties in %pOF",
278 np);
279 return -EINVAL;
280 }
281
282 return required;
283}
284
285static void at91sam9_ebi_apply_config(struct atmel_ebi_dev *ebid,
286 struct atmel_ebi_dev_config *conf)
287{
288 atmel_smc_cs_conf_apply(regmap: ebid->ebi->smc.regmap, cs: conf->cs,
289 conf: &conf->smcconf);
290}
291
292static void sama5_ebi_apply_config(struct atmel_ebi_dev *ebid,
293 struct atmel_ebi_dev_config *conf)
294{
295 atmel_hsmc_cs_conf_apply(regmap: ebid->ebi->smc.regmap, reglayout: ebid->ebi->smc.layout,
296 cs: conf->cs, conf: &conf->smcconf);
297}
298
299static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
300 int reg_cells)
301{
302 const struct atmel_ebi_caps *caps = ebi->caps;
303 struct atmel_ebi_dev_config conf = { };
304 struct device *dev = ebi->dev;
305 struct atmel_ebi_dev *ebid;
306 unsigned long cslines = 0;
307 int ret, numcs = 0, nentries, i;
308 bool apply = false;
309 u32 cs;
310
311 nentries = of_property_count_elems_of_size(np, propname: "reg",
312 elem_size: reg_cells * sizeof(u32));
313 for (i = 0; i < nentries; i++) {
314 ret = of_property_read_u32_index(np, propname: "reg", index: i * reg_cells,
315 out_value: &cs);
316 if (ret)
317 return ret;
318
319 if (cs >= AT91_EBI_NUM_CS ||
320 !(ebi->caps->available_cs & BIT(cs))) {
321 dev_err(dev, "invalid reg property in %pOF\n", np);
322 return -EINVAL;
323 }
324
325 if (!test_and_set_bit(nr: cs, addr: &cslines))
326 numcs++;
327 }
328
329 if (!numcs) {
330 dev_err(dev, "invalid reg property in %pOF\n", np);
331 return -EINVAL;
332 }
333
334 ebid = devm_kzalloc(dev: ebi->dev, struct_size(ebid, configs, numcs),
335 GFP_KERNEL);
336 if (!ebid)
337 return -ENOMEM;
338
339 ebid->ebi = ebi;
340 ebid->numcs = numcs;
341
342 ret = caps->xlate_config(ebid, np, &conf);
343 if (ret < 0)
344 return ret;
345 else if (ret)
346 apply = true;
347
348 i = 0;
349 for_each_set_bit(cs, &cslines, AT91_EBI_NUM_CS) {
350 ebid->configs[i].cs = cs;
351
352 if (apply) {
353 conf.cs = cs;
354 caps->apply_config(ebid, &conf);
355 }
356
357 caps->get_config(ebid, &ebid->configs[i]);
358
359 /*
360 * Attach the EBI device to the generic SMC logic if at least
361 * one "atmel,smc-" property is present.
362 */
363 if (ebi->caps->ebi_csa_offs && apply)
364 regmap_update_bits(map: ebi->regmap,
365 reg: ebi->caps->ebi_csa_offs,
366 BIT(cs), val: 0);
367
368 i++;
369 }
370
371 list_add_tail(new: &ebid->node, head: &ebi->devs);
372
373 return 0;
374}
375
376static const struct atmel_ebi_caps at91sam9260_ebi_caps = {
377 .available_cs = 0xff,
378 .ebi_csa_offs = AT91SAM9260_MATRIX_EBICSA,
379 .regmap_name = "atmel,matrix",
380 .get_config = at91sam9_ebi_get_config,
381 .xlate_config = atmel_ebi_xslate_smc_config,
382 .apply_config = at91sam9_ebi_apply_config,
383};
384
385static const struct atmel_ebi_caps at91sam9261_ebi_caps = {
386 .available_cs = 0xff,
387 .ebi_csa_offs = AT91SAM9261_MATRIX_EBICSA,
388 .regmap_name = "atmel,matrix",
389 .get_config = at91sam9_ebi_get_config,
390 .xlate_config = atmel_ebi_xslate_smc_config,
391 .apply_config = at91sam9_ebi_apply_config,
392};
393
394static const struct atmel_ebi_caps at91sam9263_ebi0_caps = {
395 .available_cs = 0x3f,
396 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI0CSA,
397 .regmap_name = "atmel,matrix",
398 .get_config = at91sam9_ebi_get_config,
399 .xlate_config = atmel_ebi_xslate_smc_config,
400 .apply_config = at91sam9_ebi_apply_config,
401};
402
403static const struct atmel_ebi_caps at91sam9263_ebi1_caps = {
404 .available_cs = 0x7,
405 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI1CSA,
406 .regmap_name = "atmel,matrix",
407 .get_config = at91sam9_ebi_get_config,
408 .xlate_config = atmel_ebi_xslate_smc_config,
409 .apply_config = at91sam9_ebi_apply_config,
410};
411
412static const struct atmel_ebi_caps at91sam9rl_ebi_caps = {
413 .available_cs = 0x3f,
414 .ebi_csa_offs = AT91SAM9RL_MATRIX_EBICSA,
415 .regmap_name = "atmel,matrix",
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 at91sam9g45_ebi_caps = {
422 .available_cs = 0x3f,
423 .ebi_csa_offs = AT91SAM9G45_MATRIX_EBICSA,
424 .regmap_name = "atmel,matrix",
425 .get_config = at91sam9_ebi_get_config,
426 .xlate_config = atmel_ebi_xslate_smc_config,
427 .apply_config = at91sam9_ebi_apply_config,
428};
429
430static const struct atmel_ebi_caps at91sam9x5_ebi_caps = {
431 .available_cs = 0x3f,
432 .ebi_csa_offs = AT91SAM9X5_MATRIX_EBICSA,
433 .regmap_name = "atmel,matrix",
434 .get_config = at91sam9_ebi_get_config,
435 .xlate_config = atmel_ebi_xslate_smc_config,
436 .apply_config = at91sam9_ebi_apply_config,
437};
438
439static const struct atmel_ebi_caps sama5d3_ebi_caps = {
440 .available_cs = 0xf,
441 .get_config = sama5_ebi_get_config,
442 .xlate_config = atmel_ebi_xslate_smc_config,
443 .apply_config = sama5_ebi_apply_config,
444};
445
446static const struct atmel_ebi_caps sam9x60_ebi_caps = {
447 .available_cs = 0x3f,
448 .ebi_csa_offs = AT91_SFR_CCFG_EBICSA,
449 .regmap_name = "microchip,sfr",
450 .get_config = at91sam9_ebi_get_config,
451 .xlate_config = atmel_ebi_xslate_smc_config,
452 .apply_config = at91sam9_ebi_apply_config,
453};
454
455static const struct of_device_id atmel_ebi_id_table[] = {
456 {
457 .compatible = "atmel,at91sam9260-ebi",
458 .data = &at91sam9260_ebi_caps,
459 },
460 {
461 .compatible = "atmel,at91sam9261-ebi",
462 .data = &at91sam9261_ebi_caps,
463 },
464 {
465 .compatible = "atmel,at91sam9263-ebi0",
466 .data = &at91sam9263_ebi0_caps,
467 },
468 {
469 .compatible = "atmel,at91sam9263-ebi1",
470 .data = &at91sam9263_ebi1_caps,
471 },
472 {
473 .compatible = "atmel,at91sam9rl-ebi",
474 .data = &at91sam9rl_ebi_caps,
475 },
476 {
477 .compatible = "atmel,at91sam9g45-ebi",
478 .data = &at91sam9g45_ebi_caps,
479 },
480 {
481 .compatible = "atmel,at91sam9x5-ebi",
482 .data = &at91sam9x5_ebi_caps,
483 },
484 {
485 .compatible = "atmel,sama5d3-ebi",
486 .data = &sama5d3_ebi_caps,
487 },
488 {
489 .compatible = "microchip,sam9x60-ebi",
490 .data = &sam9x60_ebi_caps,
491 },
492 { /* sentinel */ }
493};
494
495static int atmel_ebi_dev_disable(struct atmel_ebi *ebi, struct device_node *np)
496{
497 struct device *dev = ebi->dev;
498 struct property *newprop;
499
500 newprop = devm_kzalloc(dev, size: sizeof(*newprop), GFP_KERNEL);
501 if (!newprop)
502 return -ENOMEM;
503
504 newprop->name = devm_kstrdup(dev, s: "status", GFP_KERNEL);
505 if (!newprop->name)
506 return -ENOMEM;
507
508 newprop->value = devm_kstrdup(dev, s: "disabled", GFP_KERNEL);
509 if (!newprop->value)
510 return -ENOMEM;
511
512 newprop->length = sizeof("disabled");
513
514 return of_update_property(np, newprop);
515}
516
517static int atmel_ebi_probe(struct platform_device *pdev)
518{
519 struct device *dev = &pdev->dev;
520 struct device_node *child, *np = dev->of_node, *smc_np;
521 struct atmel_ebi *ebi;
522 int ret, reg_cells;
523 struct clk *clk;
524 u32 val;
525
526 ebi = devm_kzalloc(dev, size: sizeof(*ebi), GFP_KERNEL);
527 if (!ebi)
528 return -ENOMEM;
529
530 platform_set_drvdata(pdev, data: ebi);
531
532 INIT_LIST_HEAD(list: &ebi->devs);
533 ebi->caps = device_get_match_data(dev);
534 if (!ebi->caps)
535 return -EINVAL;
536 ebi->dev = dev;
537
538 clk = devm_clk_get(dev, NULL);
539 if (IS_ERR(ptr: clk))
540 return PTR_ERR(ptr: clk);
541
542 ebi->clk = clk;
543
544 smc_np = of_parse_phandle(np: dev->of_node, phandle_name: "atmel,smc", index: 0);
545
546 ebi->smc.regmap = syscon_node_to_regmap(np: smc_np);
547 if (IS_ERR(ptr: ebi->smc.regmap)) {
548 ret = PTR_ERR(ptr: ebi->smc.regmap);
549 goto put_node;
550 }
551
552 ebi->smc.layout = atmel_hsmc_get_reg_layout(np: smc_np);
553 if (IS_ERR(ptr: ebi->smc.layout)) {
554 ret = PTR_ERR(ptr: ebi->smc.layout);
555 goto put_node;
556 }
557
558 ebi->smc.clk = of_clk_get(np: smc_np, index: 0);
559 if (IS_ERR(ptr: ebi->smc.clk)) {
560 if (PTR_ERR(ptr: ebi->smc.clk) != -ENOENT) {
561 ret = PTR_ERR(ptr: ebi->smc.clk);
562 goto put_node;
563 }
564
565 ebi->smc.clk = NULL;
566 }
567 of_node_put(node: smc_np);
568 ret = clk_prepare_enable(clk: ebi->smc.clk);
569 if (ret)
570 return ret;
571
572 /*
573 * The sama5d3 does not provide an EBICSA register and thus does need
574 * to access it.
575 */
576 if (ebi->caps->ebi_csa_offs) {
577 ebi->regmap =
578 syscon_regmap_lookup_by_phandle(np,
579 property: ebi->caps->regmap_name);
580 if (IS_ERR(ptr: ebi->regmap))
581 return PTR_ERR(ptr: ebi->regmap);
582 }
583
584 ret = of_property_read_u32(np, propname: "#address-cells", out_value: &val);
585 if (ret) {
586 dev_err(dev, "missing #address-cells property\n");
587 return ret;
588 }
589
590 reg_cells = val;
591
592 ret = of_property_read_u32(np, propname: "#size-cells", out_value: &val);
593 if (ret) {
594 dev_err(dev, "missing #address-cells property\n");
595 return ret;
596 }
597
598 reg_cells += val;
599
600 for_each_available_child_of_node(np, child) {
601 if (!of_property_present(np: child, propname: "reg"))
602 continue;
603
604 ret = atmel_ebi_dev_setup(ebi, np: child, reg_cells);
605 if (ret) {
606 dev_err(dev, "failed to configure EBI bus for %pOF, disabling the device",
607 child);
608
609 ret = atmel_ebi_dev_disable(ebi, np: child);
610 if (ret) {
611 of_node_put(node: child);
612 return ret;
613 }
614 }
615 }
616
617 return of_platform_populate(root: np, NULL, NULL, parent: dev);
618
619put_node:
620 of_node_put(node: smc_np);
621 return ret;
622}
623
624static __maybe_unused int atmel_ebi_resume(struct device *dev)
625{
626 struct atmel_ebi *ebi = dev_get_drvdata(dev);
627 struct atmel_ebi_dev *ebid;
628
629 list_for_each_entry(ebid, &ebi->devs, node) {
630 int i;
631
632 for (i = 0; i < ebid->numcs; i++)
633 ebid->ebi->caps->apply_config(ebid, &ebid->configs[i]);
634 }
635
636 return 0;
637}
638
639static SIMPLE_DEV_PM_OPS(atmel_ebi_pm_ops, NULL, atmel_ebi_resume);
640
641static struct platform_driver atmel_ebi_driver = {
642 .driver = {
643 .name = "atmel-ebi",
644 .of_match_table = atmel_ebi_id_table,
645 .pm = &atmel_ebi_pm_ops,
646 },
647};
648builtin_platform_driver_probe(atmel_ebi_driver, atmel_ebi_probe);
649

source code of linux/drivers/memory/atmel-ebi.c