Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[sfrench/cifs-2.6.git] / drivers / memory / atmel-ebi.c
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
21 struct atmel_ebi_dev_config {
22         int cs;
23         struct atmel_smc_cs_conf smcconf;
24 };
25
26 struct atmel_ebi;
27
28 struct 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
36 struct 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
48 struct 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
62 struct 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
78 static 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
85 static 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
92 static 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
109 static 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
159 out:
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
170 static 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
281 static 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
288 static 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
295 static 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
373 static 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
381 static 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
389 static 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
397 static 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
405 static 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
413 static 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
421 static 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
429 static 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
436 static 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
472 static 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
494 static 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
590 static __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
605 static SIMPLE_DEV_PM_OPS(atmel_ebi_pm_ops, NULL, atmel_ebi_resume);
606
607 static 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 };
614 builtin_platform_driver_probe(atmel_ebi_driver, atmel_ebi_probe);