xref: /linux/drivers/pmdomain/imx/gpc.c (revision 0678df8271820bcf8fb4f877129f05d68a237de4)
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 int 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 	return 0;
226 }
227 
228 static const struct platform_device_id imx_pgc_power_domain_id[] = {
229 	{ "imx-pgc-power-domain"},
230 	{ },
231 };
232 
233 static struct platform_driver imx_pgc_power_domain_driver = {
234 	.driver = {
235 		.name = "imx-pgc-pd",
236 	},
237 	.probe = imx_pgc_power_domain_probe,
238 	.remove = imx_pgc_power_domain_remove,
239 	.id_table = imx_pgc_power_domain_id,
240 };
241 builtin_platform_driver(imx_pgc_power_domain_driver)
242 
243 #define GPC_PGC_DOMAIN_ARM	0
244 #define GPC_PGC_DOMAIN_PU	1
245 #define GPC_PGC_DOMAIN_DISPLAY	2
246 #define GPC_PGC_DOMAIN_PCI	3
247 
248 static struct genpd_power_state imx6_pm_domain_pu_state = {
249 	.power_off_latency_ns = 25000,
250 	.power_on_latency_ns = 2000000,
251 };
252 
253 static struct imx_pm_domain imx_gpc_domains[] = {
254 	[GPC_PGC_DOMAIN_ARM] = {
255 		.base = {
256 			.name = "ARM",
257 			.flags = GENPD_FLAG_ALWAYS_ON,
258 		},
259 	},
260 	[GPC_PGC_DOMAIN_PU] = {
261 		.base = {
262 			.name = "PU",
263 			.power_off = imx6_pm_domain_power_off,
264 			.power_on = imx6_pm_domain_power_on,
265 			.states = &imx6_pm_domain_pu_state,
266 			.state_count = 1,
267 		},
268 		.reg_offs = 0x260,
269 		.cntr_pdn_bit = 0,
270 	},
271 	[GPC_PGC_DOMAIN_DISPLAY] = {
272 		.base = {
273 			.name = "DISPLAY",
274 			.power_off = imx6_pm_domain_power_off,
275 			.power_on = imx6_pm_domain_power_on,
276 		},
277 		.reg_offs = 0x240,
278 		.cntr_pdn_bit = 4,
279 	},
280 	[GPC_PGC_DOMAIN_PCI] = {
281 		.base = {
282 			.name = "PCI",
283 			.power_off = imx6_pm_domain_power_off,
284 			.power_on = imx6_pm_domain_power_on,
285 		},
286 		.reg_offs = 0x200,
287 		.cntr_pdn_bit = 6,
288 	},
289 };
290 
291 struct imx_gpc_dt_data {
292 	int num_domains;
293 	bool err009619_present;
294 	bool err006287_present;
295 };
296 
297 static const struct imx_gpc_dt_data imx6q_dt_data = {
298 	.num_domains = 2,
299 	.err009619_present = false,
300 	.err006287_present = false,
301 };
302 
303 static const struct imx_gpc_dt_data imx6qp_dt_data = {
304 	.num_domains = 2,
305 	.err009619_present = true,
306 	.err006287_present = false,
307 };
308 
309 static const struct imx_gpc_dt_data imx6sl_dt_data = {
310 	.num_domains = 3,
311 	.err009619_present = false,
312 	.err006287_present = true,
313 };
314 
315 static const struct imx_gpc_dt_data imx6sx_dt_data = {
316 	.num_domains = 4,
317 	.err009619_present = false,
318 	.err006287_present = false,
319 };
320 
321 static const struct of_device_id imx_gpc_dt_ids[] = {
322 	{ .compatible = "fsl,imx6q-gpc", .data = &imx6q_dt_data },
323 	{ .compatible = "fsl,imx6qp-gpc", .data = &imx6qp_dt_data },
324 	{ .compatible = "fsl,imx6sl-gpc", .data = &imx6sl_dt_data },
325 	{ .compatible = "fsl,imx6sx-gpc", .data = &imx6sx_dt_data },
326 	{ }
327 };
328 
329 static const struct regmap_range yes_ranges[] = {
330 	regmap_reg_range(GPC_CNTR, GPC_CNTR),
331 	regmap_reg_range(GPC_PGC_PCI_PDN, GPC_PGC_PCI_SR),
332 	regmap_reg_range(GPC_PGC_GPU_PDN, GPC_PGC_GPU_SR),
333 	regmap_reg_range(GPC_PGC_DISP_PDN, GPC_PGC_DISP_SR),
334 };
335 
336 static const struct regmap_access_table access_table = {
337 	.yes_ranges	= yes_ranges,
338 	.n_yes_ranges	= ARRAY_SIZE(yes_ranges),
339 };
340 
341 static const struct regmap_config imx_gpc_regmap_config = {
342 	.reg_bits = 32,
343 	.val_bits = 32,
344 	.reg_stride = 4,
345 	.rd_table = &access_table,
346 	.wr_table = &access_table,
347 	.max_register = 0x2ac,
348 	.fast_io = true,
349 };
350 
351 static struct generic_pm_domain *imx_gpc_onecell_domains[] = {
352 	&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base,
353 	&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base,
354 };
355 
356 static struct genpd_onecell_data imx_gpc_onecell_data = {
357 	.domains = imx_gpc_onecell_domains,
358 	.num_domains = 2,
359 };
360 
361 static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap,
362 			       unsigned int num_domains)
363 {
364 	struct imx_pm_domain *domain;
365 	int i, ret;
366 
367 	for (i = 0; i < num_domains; i++) {
368 		domain = &imx_gpc_domains[i];
369 		domain->regmap = regmap;
370 		domain->ipg_rate_mhz = 66;
371 
372 		if (i == 1) {
373 			domain->supply = devm_regulator_get(dev, "pu");
374 			if (IS_ERR(domain->supply))
375 				return PTR_ERR(domain->supply);
376 
377 			ret = imx_pgc_get_clocks(dev, domain);
378 			if (ret)
379 				goto clk_err;
380 
381 			domain->base.power_on(&domain->base);
382 		}
383 	}
384 
385 	for (i = 0; i < num_domains; i++)
386 		pm_genpd_init(&imx_gpc_domains[i].base, NULL, false);
387 
388 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
389 		ret = of_genpd_add_provider_onecell(dev->of_node,
390 						    &imx_gpc_onecell_data);
391 		if (ret)
392 			goto genpd_err;
393 	}
394 
395 	return 0;
396 
397 genpd_err:
398 	for (i = 0; i < num_domains; i++)
399 		pm_genpd_remove(&imx_gpc_domains[i].base);
400 	imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
401 clk_err:
402 	return ret;
403 }
404 
405 static int imx_gpc_probe(struct platform_device *pdev)
406 {
407 	const struct imx_gpc_dt_data *of_id_data = device_get_match_data(&pdev->dev);
408 	struct device_node *pgc_node;
409 	struct regmap *regmap;
410 	void __iomem *base;
411 	int ret;
412 
413 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
414 
415 	/* bail out if DT too old and doesn't provide the necessary info */
416 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
417 	    !pgc_node)
418 		return 0;
419 
420 	base = devm_platform_ioremap_resource(pdev, 0);
421 	if (IS_ERR(base))
422 		return PTR_ERR(base);
423 
424 	regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
425 					   &imx_gpc_regmap_config);
426 	if (IS_ERR(regmap)) {
427 		ret = PTR_ERR(regmap);
428 		dev_err(&pdev->dev, "failed to init regmap: %d\n",
429 			ret);
430 		return ret;
431 	}
432 
433 	/*
434 	 * Disable PU power down by runtime PM if ERR009619 is present.
435 	 *
436 	 * The PRE clock will be paused for several cycles when turning on the
437 	 * PU domain LDO from power down state. If PRE is in use at that time,
438 	 * the IPU/PRG cannot get the correct display data from the PRE.
439 	 *
440 	 * This is not a concern when the whole system enters suspend state, so
441 	 * it's safe to power down PU in this case.
442 	 */
443 	if (of_id_data->err009619_present)
444 		imx_gpc_domains[GPC_PGC_DOMAIN_PU].base.flags |=
445 				GENPD_FLAG_RPM_ALWAYS_ON;
446 
447 	/* Keep DISP always on if ERR006287 is present */
448 	if (of_id_data->err006287_present)
449 		imx_gpc_domains[GPC_PGC_DOMAIN_DISPLAY].base.flags |=
450 				GENPD_FLAG_ALWAYS_ON;
451 
452 	if (!pgc_node) {
453 		ret = imx_gpc_old_dt_init(&pdev->dev, regmap,
454 					  of_id_data->num_domains);
455 		if (ret)
456 			return ret;
457 	} else {
458 		struct imx_pm_domain *domain;
459 		struct platform_device *pd_pdev;
460 		struct device_node *np;
461 		struct clk *ipg_clk;
462 		unsigned int ipg_rate_mhz;
463 		int domain_index;
464 
465 		ipg_clk = devm_clk_get(&pdev->dev, "ipg");
466 		if (IS_ERR(ipg_clk))
467 			return PTR_ERR(ipg_clk);
468 		ipg_rate_mhz = clk_get_rate(ipg_clk) / 1000000;
469 
470 		for_each_child_of_node(pgc_node, np) {
471 			ret = of_property_read_u32(np, "reg", &domain_index);
472 			if (ret) {
473 				of_node_put(np);
474 				return ret;
475 			}
476 			if (domain_index >= of_id_data->num_domains)
477 				continue;
478 
479 			pd_pdev = platform_device_alloc("imx-pgc-power-domain",
480 							domain_index);
481 			if (!pd_pdev) {
482 				of_node_put(np);
483 				return -ENOMEM;
484 			}
485 
486 			ret = platform_device_add_data(pd_pdev,
487 						       &imx_gpc_domains[domain_index],
488 						       sizeof(imx_gpc_domains[domain_index]));
489 			if (ret) {
490 				platform_device_put(pd_pdev);
491 				of_node_put(np);
492 				return ret;
493 			}
494 			domain = pd_pdev->dev.platform_data;
495 			domain->regmap = regmap;
496 			domain->ipg_rate_mhz = ipg_rate_mhz;
497 
498 			pd_pdev->dev.parent = &pdev->dev;
499 			pd_pdev->dev.of_node = np;
500 			pd_pdev->dev.fwnode = of_fwnode_handle(np);
501 
502 			ret = platform_device_add(pd_pdev);
503 			if (ret) {
504 				platform_device_put(pd_pdev);
505 				of_node_put(np);
506 				return ret;
507 			}
508 		}
509 	}
510 
511 	return 0;
512 }
513 
514 static int imx_gpc_remove(struct platform_device *pdev)
515 {
516 	struct device_node *pgc_node;
517 	int ret;
518 
519 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
520 
521 	/* bail out if DT too old and doesn't provide the necessary info */
522 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
523 	    !pgc_node)
524 		return 0;
525 
526 	/*
527 	 * If the old DT binding is used the toplevel driver needs to
528 	 * de-register the power domains
529 	 */
530 	if (!pgc_node) {
531 		of_genpd_del_provider(pdev->dev.of_node);
532 
533 		ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base);
534 		if (ret)
535 			return ret;
536 		imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
537 
538 		ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base);
539 		if (ret)
540 			return ret;
541 	}
542 
543 	return 0;
544 }
545 
546 static struct platform_driver imx_gpc_driver = {
547 	.driver = {
548 		.name = "imx-gpc",
549 		.of_match_table = imx_gpc_dt_ids,
550 	},
551 	.probe = imx_gpc_probe,
552 	.remove = imx_gpc_remove,
553 };
554 builtin_platform_driver(imx_gpc_driver)
555