xref: /linux/drivers/pmdomain/imx/gpc.c (revision b44ae980e9d026c41101d97cf96c0eb09d490b35)
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_device.h>
11 #include <linux/platform_device.h>
12 #include <linux/pm_domain.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/consumer.h>
15 
16 #define GPC_CNTR		0x000
17 
18 #define GPC_PGC_CTRL_OFFS	0x0
19 #define GPC_PGC_PUPSCR_OFFS	0x4
20 #define GPC_PGC_PDNSCR_OFFS	0x8
21 #define GPC_PGC_SW2ISO_SHIFT	0x8
22 #define GPC_PGC_SW_SHIFT	0x0
23 
24 #define GPC_PGC_PCI_PDN		0x200
25 #define GPC_PGC_PCI_SR		0x20c
26 
27 #define GPC_PGC_GPU_PDN		0x260
28 #define GPC_PGC_GPU_PUPSCR	0x264
29 #define GPC_PGC_GPU_PDNSCR	0x268
30 #define GPC_PGC_GPU_SR		0x26c
31 
32 #define GPC_PGC_DISP_PDN	0x240
33 #define GPC_PGC_DISP_SR		0x24c
34 
35 #define GPU_VPU_PUP_REQ		BIT(1)
36 #define GPU_VPU_PDN_REQ		BIT(0)
37 
38 #define GPC_CLK_MAX		7
39 
40 #define PGC_DOMAIN_FLAG_NO_PD		BIT(0)
41 
42 struct imx_pm_domain {
43 	struct generic_pm_domain base;
44 	struct regmap *regmap;
45 	struct regulator *supply;
46 	struct clk *clk[GPC_CLK_MAX];
47 	int num_clks;
48 	unsigned int reg_offs;
49 	signed char cntr_pdn_bit;
50 	unsigned int ipg_rate_mhz;
51 };
52 
53 static inline struct imx_pm_domain *
54 to_imx_pm_domain(struct generic_pm_domain *genpd)
55 {
56 	return container_of(genpd, struct imx_pm_domain, base);
57 }
58 
59 static int imx6_pm_domain_power_off(struct generic_pm_domain *genpd)
60 {
61 	struct imx_pm_domain *pd = to_imx_pm_domain(genpd);
62 	int iso, iso2sw;
63 	u32 val;
64 
65 	/* Read ISO and ISO2SW power down delays */
66 	regmap_read(pd->regmap, pd->reg_offs + GPC_PGC_PDNSCR_OFFS, &val);
67 	iso = val & 0x3f;
68 	iso2sw = (val >> 8) & 0x3f;
69 
70 	/* Gate off domain when powered down */
71 	regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_CTRL_OFFS,
72 			   0x1, 0x1);
73 
74 	/* Request GPC to power down domain */
75 	val = BIT(pd->cntr_pdn_bit);
76 	regmap_update_bits(pd->regmap, GPC_CNTR, val, val);
77 
78 	/* Wait ISO + ISO2SW IPG clock cycles */
79 	udelay(DIV_ROUND_UP(iso + iso2sw, pd->ipg_rate_mhz));
80 
81 	if (pd->supply)
82 		regulator_disable(pd->supply);
83 
84 	return 0;
85 }
86 
87 static int imx6_pm_domain_power_on(struct generic_pm_domain *genpd)
88 {
89 	struct imx_pm_domain *pd = to_imx_pm_domain(genpd);
90 	int i, ret;
91 	u32 val, req;
92 
93 	if (pd->supply) {
94 		ret = regulator_enable(pd->supply);
95 		if (ret) {
96 			pr_err("%s: failed to enable regulator: %d\n",
97 			       __func__, ret);
98 			return ret;
99 		}
100 	}
101 
102 	/* Enable reset clocks for all devices in the domain */
103 	for (i = 0; i < pd->num_clks; i++)
104 		clk_prepare_enable(pd->clk[i]);
105 
106 	/* Gate off domain when powered down */
107 	regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_CTRL_OFFS,
108 			   0x1, 0x1);
109 
110 	/* Request GPC to power up domain */
111 	req = BIT(pd->cntr_pdn_bit + 1);
112 	regmap_update_bits(pd->regmap, GPC_CNTR, req, req);
113 
114 	/* Wait for the PGC to handle the request */
115 	ret = regmap_read_poll_timeout(pd->regmap, GPC_CNTR, val, !(val & req),
116 				       1, 50);
117 	if (ret)
118 		pr_err("powerup request on domain %s timed out\n", genpd->name);
119 
120 	/* Wait for reset to propagate through peripherals */
121 	usleep_range(5, 10);
122 
123 	/* Disable reset clocks for all devices in the domain */
124 	for (i = 0; i < pd->num_clks; i++)
125 		clk_disable_unprepare(pd->clk[i]);
126 
127 	return 0;
128 }
129 
130 static int imx_pgc_get_clocks(struct device *dev, struct imx_pm_domain *domain)
131 {
132 	int i, ret;
133 
134 	for (i = 0; ; i++) {
135 		struct clk *clk = of_clk_get(dev->of_node, i);
136 		if (IS_ERR(clk))
137 			break;
138 		if (i >= GPC_CLK_MAX) {
139 			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
140 			ret = -EINVAL;
141 			goto clk_err;
142 		}
143 		domain->clk[i] = clk;
144 	}
145 	domain->num_clks = i;
146 
147 	return 0;
148 
149 clk_err:
150 	while (i--)
151 		clk_put(domain->clk[i]);
152 
153 	return ret;
154 }
155 
156 static void imx_pgc_put_clocks(struct imx_pm_domain *domain)
157 {
158 	int i;
159 
160 	for (i = domain->num_clks - 1; i >= 0; i--)
161 		clk_put(domain->clk[i]);
162 }
163 
164 static int imx_pgc_parse_dt(struct device *dev, struct imx_pm_domain *domain)
165 {
166 	/* try to get the domain supply regulator */
167 	domain->supply = devm_regulator_get_optional(dev, "power");
168 	if (IS_ERR(domain->supply)) {
169 		if (PTR_ERR(domain->supply) == -ENODEV)
170 			domain->supply = NULL;
171 		else
172 			return PTR_ERR(domain->supply);
173 	}
174 
175 	/* try to get all clocks needed for reset propagation */
176 	return imx_pgc_get_clocks(dev, domain);
177 }
178 
179 static int imx_pgc_power_domain_probe(struct platform_device *pdev)
180 {
181 	struct imx_pm_domain *domain = pdev->dev.platform_data;
182 	struct device *dev = &pdev->dev;
183 	int ret;
184 
185 	/* if this PD is associated with a DT node try to parse it */
186 	if (dev->of_node) {
187 		ret = imx_pgc_parse_dt(dev, domain);
188 		if (ret)
189 			return ret;
190 	}
191 
192 	/* initially power on the domain */
193 	if (domain->base.power_on)
194 		domain->base.power_on(&domain->base);
195 
196 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
197 		pm_genpd_init(&domain->base, NULL, false);
198 		ret = of_genpd_add_provider_simple(dev->of_node, &domain->base);
199 		if (ret)
200 			goto genpd_err;
201 	}
202 
203 	device_link_add(dev, dev->parent, DL_FLAG_AUTOREMOVE_CONSUMER);
204 
205 	return 0;
206 
207 genpd_err:
208 	pm_genpd_remove(&domain->base);
209 	imx_pgc_put_clocks(domain);
210 
211 	return ret;
212 }
213 
214 static int imx_pgc_power_domain_remove(struct platform_device *pdev)
215 {
216 	struct imx_pm_domain *domain = pdev->dev.platform_data;
217 
218 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
219 		of_genpd_del_provider(pdev->dev.of_node);
220 		pm_genpd_remove(&domain->base);
221 		imx_pgc_put_clocks(domain);
222 	}
223 
224 	return 0;
225 }
226 
227 static const struct platform_device_id imx_pgc_power_domain_id[] = {
228 	{ "imx-pgc-power-domain"},
229 	{ },
230 };
231 
232 static struct platform_driver imx_pgc_power_domain_driver = {
233 	.driver = {
234 		.name = "imx-pgc-pd",
235 	},
236 	.probe = imx_pgc_power_domain_probe,
237 	.remove = imx_pgc_power_domain_remove,
238 	.id_table = imx_pgc_power_domain_id,
239 };
240 builtin_platform_driver(imx_pgc_power_domain_driver)
241 
242 #define GPC_PGC_DOMAIN_ARM	0
243 #define GPC_PGC_DOMAIN_PU	1
244 #define GPC_PGC_DOMAIN_DISPLAY	2
245 #define GPC_PGC_DOMAIN_PCI	3
246 
247 static struct genpd_power_state imx6_pm_domain_pu_state = {
248 	.power_off_latency_ns = 25000,
249 	.power_on_latency_ns = 2000000,
250 };
251 
252 static struct imx_pm_domain imx_gpc_domains[] = {
253 	[GPC_PGC_DOMAIN_ARM] = {
254 		.base = {
255 			.name = "ARM",
256 			.flags = GENPD_FLAG_ALWAYS_ON,
257 		},
258 	},
259 	[GPC_PGC_DOMAIN_PU] = {
260 		.base = {
261 			.name = "PU",
262 			.power_off = imx6_pm_domain_power_off,
263 			.power_on = imx6_pm_domain_power_on,
264 			.states = &imx6_pm_domain_pu_state,
265 			.state_count = 1,
266 		},
267 		.reg_offs = 0x260,
268 		.cntr_pdn_bit = 0,
269 	},
270 	[GPC_PGC_DOMAIN_DISPLAY] = {
271 		.base = {
272 			.name = "DISPLAY",
273 			.power_off = imx6_pm_domain_power_off,
274 			.power_on = imx6_pm_domain_power_on,
275 		},
276 		.reg_offs = 0x240,
277 		.cntr_pdn_bit = 4,
278 	},
279 	[GPC_PGC_DOMAIN_PCI] = {
280 		.base = {
281 			.name = "PCI",
282 			.power_off = imx6_pm_domain_power_off,
283 			.power_on = imx6_pm_domain_power_on,
284 		},
285 		.reg_offs = 0x200,
286 		.cntr_pdn_bit = 6,
287 	},
288 };
289 
290 struct imx_gpc_dt_data {
291 	int num_domains;
292 	bool err009619_present;
293 	bool err006287_present;
294 };
295 
296 static const struct imx_gpc_dt_data imx6q_dt_data = {
297 	.num_domains = 2,
298 	.err009619_present = false,
299 	.err006287_present = false,
300 };
301 
302 static const struct imx_gpc_dt_data imx6qp_dt_data = {
303 	.num_domains = 2,
304 	.err009619_present = true,
305 	.err006287_present = false,
306 };
307 
308 static const struct imx_gpc_dt_data imx6sl_dt_data = {
309 	.num_domains = 3,
310 	.err009619_present = false,
311 	.err006287_present = true,
312 };
313 
314 static const struct imx_gpc_dt_data imx6sx_dt_data = {
315 	.num_domains = 4,
316 	.err009619_present = false,
317 	.err006287_present = false,
318 };
319 
320 static const struct of_device_id imx_gpc_dt_ids[] = {
321 	{ .compatible = "fsl,imx6q-gpc", .data = &imx6q_dt_data },
322 	{ .compatible = "fsl,imx6qp-gpc", .data = &imx6qp_dt_data },
323 	{ .compatible = "fsl,imx6sl-gpc", .data = &imx6sl_dt_data },
324 	{ .compatible = "fsl,imx6sx-gpc", .data = &imx6sx_dt_data },
325 	{ }
326 };
327 
328 static const struct regmap_range yes_ranges[] = {
329 	regmap_reg_range(GPC_CNTR, GPC_CNTR),
330 	regmap_reg_range(GPC_PGC_PCI_PDN, GPC_PGC_PCI_SR),
331 	regmap_reg_range(GPC_PGC_GPU_PDN, GPC_PGC_GPU_SR),
332 	regmap_reg_range(GPC_PGC_DISP_PDN, GPC_PGC_DISP_SR),
333 };
334 
335 static const struct regmap_access_table access_table = {
336 	.yes_ranges	= yes_ranges,
337 	.n_yes_ranges	= ARRAY_SIZE(yes_ranges),
338 };
339 
340 static const struct regmap_config imx_gpc_regmap_config = {
341 	.reg_bits = 32,
342 	.val_bits = 32,
343 	.reg_stride = 4,
344 	.rd_table = &access_table,
345 	.wr_table = &access_table,
346 	.max_register = 0x2ac,
347 	.fast_io = true,
348 };
349 
350 static struct generic_pm_domain *imx_gpc_onecell_domains[] = {
351 	&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base,
352 	&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base,
353 };
354 
355 static struct genpd_onecell_data imx_gpc_onecell_data = {
356 	.domains = imx_gpc_onecell_domains,
357 	.num_domains = 2,
358 };
359 
360 static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap,
361 			       unsigned int num_domains)
362 {
363 	struct imx_pm_domain *domain;
364 	int i, ret;
365 
366 	for (i = 0; i < num_domains; i++) {
367 		domain = &imx_gpc_domains[i];
368 		domain->regmap = regmap;
369 		domain->ipg_rate_mhz = 66;
370 
371 		if (i == 1) {
372 			domain->supply = devm_regulator_get(dev, "pu");
373 			if (IS_ERR(domain->supply))
374 				return PTR_ERR(domain->supply);
375 
376 			ret = imx_pgc_get_clocks(dev, domain);
377 			if (ret)
378 				goto clk_err;
379 
380 			domain->base.power_on(&domain->base);
381 		}
382 	}
383 
384 	for (i = 0; i < num_domains; i++)
385 		pm_genpd_init(&imx_gpc_domains[i].base, NULL, false);
386 
387 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
388 		ret = of_genpd_add_provider_onecell(dev->of_node,
389 						    &imx_gpc_onecell_data);
390 		if (ret)
391 			goto genpd_err;
392 	}
393 
394 	return 0;
395 
396 genpd_err:
397 	for (i = 0; i < num_domains; i++)
398 		pm_genpd_remove(&imx_gpc_domains[i].base);
399 	imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
400 clk_err:
401 	return ret;
402 }
403 
404 static int imx_gpc_probe(struct platform_device *pdev)
405 {
406 	const struct of_device_id *of_id =
407 			of_match_device(imx_gpc_dt_ids, &pdev->dev);
408 	const struct imx_gpc_dt_data *of_id_data = of_id->data;
409 	struct device_node *pgc_node;
410 	struct regmap *regmap;
411 	void __iomem *base;
412 	int ret;
413 
414 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
415 
416 	/* bail out if DT too old and doesn't provide the necessary info */
417 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
418 	    !pgc_node)
419 		return 0;
420 
421 	base = devm_platform_ioremap_resource(pdev, 0);
422 	if (IS_ERR(base))
423 		return PTR_ERR(base);
424 
425 	regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
426 					   &imx_gpc_regmap_config);
427 	if (IS_ERR(regmap)) {
428 		ret = PTR_ERR(regmap);
429 		dev_err(&pdev->dev, "failed to init regmap: %d\n",
430 			ret);
431 		return ret;
432 	}
433 
434 	/*
435 	 * Disable PU power down by runtime PM if ERR009619 is present.
436 	 *
437 	 * The PRE clock will be paused for several cycles when turning on the
438 	 * PU domain LDO from power down state. If PRE is in use at that time,
439 	 * the IPU/PRG cannot get the correct display data from the PRE.
440 	 *
441 	 * This is not a concern when the whole system enters suspend state, so
442 	 * it's safe to power down PU in this case.
443 	 */
444 	if (of_id_data->err009619_present)
445 		imx_gpc_domains[GPC_PGC_DOMAIN_PU].base.flags |=
446 				GENPD_FLAG_RPM_ALWAYS_ON;
447 
448 	/* Keep DISP always on if ERR006287 is present */
449 	if (of_id_data->err006287_present)
450 		imx_gpc_domains[GPC_PGC_DOMAIN_DISPLAY].base.flags |=
451 				GENPD_FLAG_ALWAYS_ON;
452 
453 	if (!pgc_node) {
454 		ret = imx_gpc_old_dt_init(&pdev->dev, regmap,
455 					  of_id_data->num_domains);
456 		if (ret)
457 			return ret;
458 	} else {
459 		struct imx_pm_domain *domain;
460 		struct platform_device *pd_pdev;
461 		struct device_node *np;
462 		struct clk *ipg_clk;
463 		unsigned int ipg_rate_mhz;
464 		int domain_index;
465 
466 		ipg_clk = devm_clk_get(&pdev->dev, "ipg");
467 		if (IS_ERR(ipg_clk))
468 			return PTR_ERR(ipg_clk);
469 		ipg_rate_mhz = clk_get_rate(ipg_clk) / 1000000;
470 
471 		for_each_child_of_node(pgc_node, np) {
472 			ret = of_property_read_u32(np, "reg", &domain_index);
473 			if (ret) {
474 				of_node_put(np);
475 				return ret;
476 			}
477 			if (domain_index >= of_id_data->num_domains)
478 				continue;
479 
480 			pd_pdev = platform_device_alloc("imx-pgc-power-domain",
481 							domain_index);
482 			if (!pd_pdev) {
483 				of_node_put(np);
484 				return -ENOMEM;
485 			}
486 
487 			ret = platform_device_add_data(pd_pdev,
488 						       &imx_gpc_domains[domain_index],
489 						       sizeof(imx_gpc_domains[domain_index]));
490 			if (ret) {
491 				platform_device_put(pd_pdev);
492 				of_node_put(np);
493 				return ret;
494 			}
495 			domain = pd_pdev->dev.platform_data;
496 			domain->regmap = regmap;
497 			domain->ipg_rate_mhz = ipg_rate_mhz;
498 
499 			pd_pdev->dev.parent = &pdev->dev;
500 			pd_pdev->dev.of_node = 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