xref: /linux/drivers/pmdomain/imx/gpc.c (revision 3be042cf46feeedf664152d063376b5c17026d1d)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
4  * Copyright 2011-2013 Freescale Semiconductor, Inc.
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/io.h>
10 #include <linux/of.h>
11 #include <linux/platform_device.h>
12 #include <linux/pm_domain.h>
13 #include <linux/property.h>
14 #include <linux/regmap.h>
15 #include <linux/regulator/consumer.h>
16 
17 #define GPC_CNTR		0x000
18 
19 #define GPC_PGC_CTRL_OFFS	0x0
20 #define GPC_PGC_PUPSCR_OFFS	0x4
21 #define GPC_PGC_PDNSCR_OFFS	0x8
22 #define GPC_PGC_SW2ISO_SHIFT	0x8
23 #define GPC_PGC_SW_SHIFT	0x0
24 
25 #define GPC_PGC_PCI_PDN		0x200
26 #define GPC_PGC_PCI_SR		0x20c
27 
28 #define GPC_PGC_GPU_PDN		0x260
29 #define GPC_PGC_GPU_PUPSCR	0x264
30 #define GPC_PGC_GPU_PDNSCR	0x268
31 #define GPC_PGC_GPU_SR		0x26c
32 
33 #define GPC_PGC_DISP_PDN	0x240
34 #define GPC_PGC_DISP_SR		0x24c
35 
36 #define GPU_VPU_PUP_REQ		BIT(1)
37 #define GPU_VPU_PDN_REQ		BIT(0)
38 
39 #define GPC_CLK_MAX		7
40 
41 #define PGC_DOMAIN_FLAG_NO_PD		BIT(0)
42 
43 struct imx_pm_domain {
44 	struct generic_pm_domain base;
45 	struct regmap *regmap;
46 	struct regulator *supply;
47 	struct clk *clk[GPC_CLK_MAX];
48 	int num_clks;
49 	unsigned int reg_offs;
50 	signed char cntr_pdn_bit;
51 	unsigned int ipg_rate_mhz;
52 };
53 
54 static inline struct imx_pm_domain *
55 to_imx_pm_domain(struct generic_pm_domain *genpd)
56 {
57 	return container_of(genpd, struct imx_pm_domain, base);
58 }
59 
60 static int imx6_pm_domain_power_off(struct generic_pm_domain *genpd)
61 {
62 	struct imx_pm_domain *pd = to_imx_pm_domain(genpd);
63 	int iso, iso2sw;
64 	u32 val;
65 
66 	/* Read ISO and ISO2SW power down delays */
67 	regmap_read(pd->regmap, pd->reg_offs + GPC_PGC_PDNSCR_OFFS, &val);
68 	iso = val & 0x3f;
69 	iso2sw = (val >> 8) & 0x3f;
70 
71 	/* Gate off domain when powered down */
72 	regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_CTRL_OFFS,
73 			   0x1, 0x1);
74 
75 	/* Request GPC to power down domain */
76 	val = BIT(pd->cntr_pdn_bit);
77 	regmap_update_bits(pd->regmap, GPC_CNTR, val, val);
78 
79 	/* Wait ISO + ISO2SW IPG clock cycles */
80 	udelay(DIV_ROUND_UP(iso + iso2sw, pd->ipg_rate_mhz));
81 
82 	if (pd->supply)
83 		regulator_disable(pd->supply);
84 
85 	return 0;
86 }
87 
88 static int imx6_pm_domain_power_on(struct generic_pm_domain *genpd)
89 {
90 	struct imx_pm_domain *pd = to_imx_pm_domain(genpd);
91 	int i, ret;
92 	u32 val, req;
93 
94 	if (pd->supply) {
95 		ret = regulator_enable(pd->supply);
96 		if (ret) {
97 			pr_err("%s: failed to enable regulator: %d\n",
98 			       __func__, ret);
99 			return ret;
100 		}
101 	}
102 
103 	/* Enable reset clocks for all devices in the domain */
104 	for (i = 0; i < pd->num_clks; i++)
105 		clk_prepare_enable(pd->clk[i]);
106 
107 	/* Gate off domain when powered down */
108 	regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_CTRL_OFFS,
109 			   0x1, 0x1);
110 
111 	/* Request GPC to power up domain */
112 	req = BIT(pd->cntr_pdn_bit + 1);
113 	regmap_update_bits(pd->regmap, GPC_CNTR, req, req);
114 
115 	/* Wait for the PGC to handle the request */
116 	ret = regmap_read_poll_timeout(pd->regmap, GPC_CNTR, val, !(val & req),
117 				       1, 50);
118 	if (ret)
119 		pr_err("powerup request on domain %s timed out\n", genpd->name);
120 
121 	/* Wait for reset to propagate through peripherals */
122 	usleep_range(5, 10);
123 
124 	/* Disable reset clocks for all devices in the domain */
125 	for (i = 0; i < pd->num_clks; i++)
126 		clk_disable_unprepare(pd->clk[i]);
127 
128 	return 0;
129 }
130 
131 static int imx_pgc_get_clocks(struct device *dev, struct imx_pm_domain *domain)
132 {
133 	int i, ret;
134 
135 	for (i = 0; ; i++) {
136 		struct clk *clk = of_clk_get(dev->of_node, i);
137 		if (IS_ERR(clk))
138 			break;
139 		if (i >= GPC_CLK_MAX) {
140 			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
141 			ret = -EINVAL;
142 			goto clk_err;
143 		}
144 		domain->clk[i] = clk;
145 	}
146 	domain->num_clks = i;
147 
148 	return 0;
149 
150 clk_err:
151 	while (i--)
152 		clk_put(domain->clk[i]);
153 
154 	return ret;
155 }
156 
157 static void imx_pgc_put_clocks(struct imx_pm_domain *domain)
158 {
159 	int i;
160 
161 	for (i = domain->num_clks - 1; i >= 0; i--)
162 		clk_put(domain->clk[i]);
163 }
164 
165 static int imx_pgc_parse_dt(struct device *dev, struct imx_pm_domain *domain)
166 {
167 	/* try to get the domain supply regulator */
168 	domain->supply = devm_regulator_get_optional(dev, "power");
169 	if (IS_ERR(domain->supply)) {
170 		if (PTR_ERR(domain->supply) == -ENODEV)
171 			domain->supply = NULL;
172 		else
173 			return PTR_ERR(domain->supply);
174 	}
175 
176 	/* try to get all clocks needed for reset propagation */
177 	return imx_pgc_get_clocks(dev, domain);
178 }
179 
180 static int imx_pgc_power_domain_probe(struct platform_device *pdev)
181 {
182 	struct imx_pm_domain *domain = pdev->dev.platform_data;
183 	struct device *dev = &pdev->dev;
184 	int ret;
185 
186 	/* if this PD is associated with a DT node try to parse it */
187 	if (dev->of_node) {
188 		ret = imx_pgc_parse_dt(dev, domain);
189 		if (ret)
190 			return ret;
191 	}
192 
193 	/* initially power on the domain */
194 	if (domain->base.power_on)
195 		domain->base.power_on(&domain->base);
196 
197 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
198 		pm_genpd_init(&domain->base, NULL, false);
199 		ret = of_genpd_add_provider_simple(dev->of_node, &domain->base);
200 		if (ret)
201 			goto genpd_err;
202 	}
203 
204 	device_link_add(dev, dev->parent, DL_FLAG_AUTOREMOVE_CONSUMER);
205 
206 	return 0;
207 
208 genpd_err:
209 	pm_genpd_remove(&domain->base);
210 	imx_pgc_put_clocks(domain);
211 
212 	return ret;
213 }
214 
215 static void imx_pgc_power_domain_remove(struct platform_device *pdev)
216 {
217 	struct imx_pm_domain *domain = pdev->dev.platform_data;
218 
219 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
220 		of_genpd_del_provider(pdev->dev.of_node);
221 		pm_genpd_remove(&domain->base);
222 		imx_pgc_put_clocks(domain);
223 	}
224 }
225 
226 static const struct platform_device_id imx_pgc_power_domain_id[] = {
227 	{ "imx-pgc-power-domain"},
228 	{ },
229 };
230 
231 static struct platform_driver imx_pgc_power_domain_driver = {
232 	.driver = {
233 		.name = "imx-pgc-pd",
234 	},
235 	.probe = imx_pgc_power_domain_probe,
236 	.remove_new = imx_pgc_power_domain_remove,
237 	.id_table = imx_pgc_power_domain_id,
238 };
239 builtin_platform_driver(imx_pgc_power_domain_driver)
240 
241 #define GPC_PGC_DOMAIN_ARM	0
242 #define GPC_PGC_DOMAIN_PU	1
243 #define GPC_PGC_DOMAIN_DISPLAY	2
244 #define GPC_PGC_DOMAIN_PCI	3
245 
246 static struct genpd_power_state imx6_pm_domain_pu_state = {
247 	.power_off_latency_ns = 25000,
248 	.power_on_latency_ns = 2000000,
249 };
250 
251 static struct imx_pm_domain imx_gpc_domains[] = {
252 	[GPC_PGC_DOMAIN_ARM] = {
253 		.base = {
254 			.name = "ARM",
255 			.flags = GENPD_FLAG_ALWAYS_ON,
256 		},
257 	},
258 	[GPC_PGC_DOMAIN_PU] = {
259 		.base = {
260 			.name = "PU",
261 			.power_off = imx6_pm_domain_power_off,
262 			.power_on = imx6_pm_domain_power_on,
263 			.states = &imx6_pm_domain_pu_state,
264 			.state_count = 1,
265 		},
266 		.reg_offs = 0x260,
267 		.cntr_pdn_bit = 0,
268 	},
269 	[GPC_PGC_DOMAIN_DISPLAY] = {
270 		.base = {
271 			.name = "DISPLAY",
272 			.power_off = imx6_pm_domain_power_off,
273 			.power_on = imx6_pm_domain_power_on,
274 		},
275 		.reg_offs = 0x240,
276 		.cntr_pdn_bit = 4,
277 	},
278 	[GPC_PGC_DOMAIN_PCI] = {
279 		.base = {
280 			.name = "PCI",
281 			.power_off = imx6_pm_domain_power_off,
282 			.power_on = imx6_pm_domain_power_on,
283 		},
284 		.reg_offs = 0x200,
285 		.cntr_pdn_bit = 6,
286 	},
287 };
288 
289 struct imx_gpc_dt_data {
290 	int num_domains;
291 	bool err009619_present;
292 	bool err006287_present;
293 };
294 
295 static const struct imx_gpc_dt_data imx6q_dt_data = {
296 	.num_domains = 2,
297 	.err009619_present = false,
298 	.err006287_present = false,
299 };
300 
301 static const struct imx_gpc_dt_data imx6qp_dt_data = {
302 	.num_domains = 2,
303 	.err009619_present = true,
304 	.err006287_present = false,
305 };
306 
307 static const struct imx_gpc_dt_data imx6sl_dt_data = {
308 	.num_domains = 3,
309 	.err009619_present = false,
310 	.err006287_present = true,
311 };
312 
313 static const struct imx_gpc_dt_data imx6sx_dt_data = {
314 	.num_domains = 4,
315 	.err009619_present = false,
316 	.err006287_present = false,
317 };
318 
319 static const struct of_device_id imx_gpc_dt_ids[] = {
320 	{ .compatible = "fsl,imx6q-gpc", .data = &imx6q_dt_data },
321 	{ .compatible = "fsl,imx6qp-gpc", .data = &imx6qp_dt_data },
322 	{ .compatible = "fsl,imx6sl-gpc", .data = &imx6sl_dt_data },
323 	{ .compatible = "fsl,imx6sx-gpc", .data = &imx6sx_dt_data },
324 	{ }
325 };
326 
327 static const struct regmap_range yes_ranges[] = {
328 	regmap_reg_range(GPC_CNTR, GPC_CNTR),
329 	regmap_reg_range(GPC_PGC_PCI_PDN, GPC_PGC_PCI_SR),
330 	regmap_reg_range(GPC_PGC_GPU_PDN, GPC_PGC_GPU_SR),
331 	regmap_reg_range(GPC_PGC_DISP_PDN, GPC_PGC_DISP_SR),
332 };
333 
334 static const struct regmap_access_table access_table = {
335 	.yes_ranges	= yes_ranges,
336 	.n_yes_ranges	= ARRAY_SIZE(yes_ranges),
337 };
338 
339 static const struct regmap_config imx_gpc_regmap_config = {
340 	.reg_bits = 32,
341 	.val_bits = 32,
342 	.reg_stride = 4,
343 	.rd_table = &access_table,
344 	.wr_table = &access_table,
345 	.max_register = 0x2ac,
346 	.fast_io = true,
347 };
348 
349 static struct generic_pm_domain *imx_gpc_onecell_domains[] = {
350 	&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base,
351 	&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base,
352 };
353 
354 static struct genpd_onecell_data imx_gpc_onecell_data = {
355 	.domains = imx_gpc_onecell_domains,
356 	.num_domains = 2,
357 };
358 
359 static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap,
360 			       unsigned int num_domains)
361 {
362 	struct imx_pm_domain *domain;
363 	int i, ret;
364 
365 	for (i = 0; i < num_domains; i++) {
366 		domain = &imx_gpc_domains[i];
367 		domain->regmap = regmap;
368 		domain->ipg_rate_mhz = 66;
369 
370 		if (i == 1) {
371 			domain->supply = devm_regulator_get(dev, "pu");
372 			if (IS_ERR(domain->supply))
373 				return PTR_ERR(domain->supply);
374 
375 			ret = imx_pgc_get_clocks(dev, domain);
376 			if (ret)
377 				goto clk_err;
378 
379 			domain->base.power_on(&domain->base);
380 		}
381 	}
382 
383 	for (i = 0; i < num_domains; i++)
384 		pm_genpd_init(&imx_gpc_domains[i].base, NULL, false);
385 
386 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
387 		ret = of_genpd_add_provider_onecell(dev->of_node,
388 						    &imx_gpc_onecell_data);
389 		if (ret)
390 			goto genpd_err;
391 	}
392 
393 	return 0;
394 
395 genpd_err:
396 	for (i = 0; i < num_domains; i++)
397 		pm_genpd_remove(&imx_gpc_domains[i].base);
398 	imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
399 clk_err:
400 	return ret;
401 }
402 
403 static int imx_gpc_probe(struct platform_device *pdev)
404 {
405 	const struct imx_gpc_dt_data *of_id_data = device_get_match_data(&pdev->dev);
406 	struct device_node *pgc_node;
407 	struct regmap *regmap;
408 	void __iomem *base;
409 	int ret;
410 
411 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
412 
413 	/* bail out if DT too old and doesn't provide the necessary info */
414 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
415 	    !pgc_node)
416 		return 0;
417 
418 	base = devm_platform_ioremap_resource(pdev, 0);
419 	if (IS_ERR(base))
420 		return PTR_ERR(base);
421 
422 	regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
423 					   &imx_gpc_regmap_config);
424 	if (IS_ERR(regmap)) {
425 		ret = PTR_ERR(regmap);
426 		dev_err(&pdev->dev, "failed to init regmap: %d\n",
427 			ret);
428 		return ret;
429 	}
430 
431 	/*
432 	 * Disable PU power down by runtime PM if ERR009619 is present.
433 	 *
434 	 * The PRE clock will be paused for several cycles when turning on the
435 	 * PU domain LDO from power down state. If PRE is in use at that time,
436 	 * the IPU/PRG cannot get the correct display data from the PRE.
437 	 *
438 	 * This is not a concern when the whole system enters suspend state, so
439 	 * it's safe to power down PU in this case.
440 	 */
441 	if (of_id_data->err009619_present)
442 		imx_gpc_domains[GPC_PGC_DOMAIN_PU].base.flags |=
443 				GENPD_FLAG_RPM_ALWAYS_ON;
444 
445 	/* Keep DISP always on if ERR006287 is present */
446 	if (of_id_data->err006287_present)
447 		imx_gpc_domains[GPC_PGC_DOMAIN_DISPLAY].base.flags |=
448 				GENPD_FLAG_ALWAYS_ON;
449 
450 	if (!pgc_node) {
451 		ret = imx_gpc_old_dt_init(&pdev->dev, regmap,
452 					  of_id_data->num_domains);
453 		if (ret)
454 			return ret;
455 	} else {
456 		struct imx_pm_domain *domain;
457 		struct platform_device *pd_pdev;
458 		struct device_node *np;
459 		struct clk *ipg_clk;
460 		unsigned int ipg_rate_mhz;
461 		int domain_index;
462 
463 		ipg_clk = devm_clk_get(&pdev->dev, "ipg");
464 		if (IS_ERR(ipg_clk))
465 			return PTR_ERR(ipg_clk);
466 		ipg_rate_mhz = clk_get_rate(ipg_clk) / 1000000;
467 
468 		for_each_child_of_node(pgc_node, np) {
469 			ret = of_property_read_u32(np, "reg", &domain_index);
470 			if (ret) {
471 				of_node_put(np);
472 				return ret;
473 			}
474 			if (domain_index >= of_id_data->num_domains)
475 				continue;
476 
477 			pd_pdev = platform_device_alloc("imx-pgc-power-domain",
478 							domain_index);
479 			if (!pd_pdev) {
480 				of_node_put(np);
481 				return -ENOMEM;
482 			}
483 
484 			ret = platform_device_add_data(pd_pdev,
485 						       &imx_gpc_domains[domain_index],
486 						       sizeof(imx_gpc_domains[domain_index]));
487 			if (ret) {
488 				platform_device_put(pd_pdev);
489 				of_node_put(np);
490 				return ret;
491 			}
492 			domain = pd_pdev->dev.platform_data;
493 			domain->regmap = regmap;
494 			domain->ipg_rate_mhz = ipg_rate_mhz;
495 
496 			pd_pdev->dev.parent = &pdev->dev;
497 			pd_pdev->dev.of_node = np;
498 			pd_pdev->dev.fwnode = of_fwnode_handle(np);
499 
500 			ret = platform_device_add(pd_pdev);
501 			if (ret) {
502 				platform_device_put(pd_pdev);
503 				of_node_put(np);
504 				return ret;
505 			}
506 		}
507 	}
508 
509 	return 0;
510 }
511 
512 static void imx_gpc_remove(struct platform_device *pdev)
513 {
514 	struct device_node *pgc_node;
515 	int ret;
516 
517 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
518 
519 	/* bail out if DT too old and doesn't provide the necessary info */
520 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
521 	    !pgc_node)
522 		return;
523 
524 	/*
525 	 * If the old DT binding is used the toplevel driver needs to
526 	 * de-register the power domains
527 	 */
528 	if (!pgc_node) {
529 		of_genpd_del_provider(pdev->dev.of_node);
530 
531 		ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base);
532 		if (ret) {
533 			dev_err(&pdev->dev, "Failed to remove PU power domain (%pe)\n",
534 				ERR_PTR(ret));
535 			return;
536 		}
537 		imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
538 
539 		ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base);
540 		if (ret) {
541 			dev_err(&pdev->dev, "Failed to remove ARM power domain (%pe)\n",
542 				ERR_PTR(ret));
543 			return;
544 		}
545 	}
546 }
547 
548 static struct platform_driver imx_gpc_driver = {
549 	.driver = {
550 		.name = "imx-gpc",
551 		.of_match_table = imx_gpc_dt_ids,
552 	},
553 	.probe = imx_gpc_probe,
554 	.remove_new = imx_gpc_remove,
555 };
556 builtin_platform_driver(imx_gpc_driver)
557