xref: /linux/drivers/pmdomain/imx/gpc.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
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 = 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 };
347 
348 static struct generic_pm_domain *imx_gpc_onecell_domains[] = {
349 	&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base,
350 	&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base,
351 };
352 
353 static struct genpd_onecell_data imx_gpc_onecell_data = {
354 	.domains = imx_gpc_onecell_domains,
355 	.num_domains = 2,
356 };
357 
358 static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap,
359 			       unsigned int num_domains)
360 {
361 	struct imx_pm_domain *domain;
362 	int i, ret;
363 
364 	for (i = 0; i < num_domains; i++) {
365 		domain = &imx_gpc_domains[i];
366 		domain->regmap = regmap;
367 		domain->ipg_rate_mhz = 66;
368 
369 		if (i == 1) {
370 			domain->supply = devm_regulator_get(dev, "pu");
371 			if (IS_ERR(domain->supply))
372 				return PTR_ERR(domain->supply);
373 
374 			ret = imx_pgc_get_clocks(dev, domain);
375 			if (ret)
376 				goto clk_err;
377 
378 			domain->base.power_on(&domain->base);
379 		}
380 	}
381 
382 	for (i = 0; i < num_domains; i++)
383 		pm_genpd_init(&imx_gpc_domains[i].base, NULL, false);
384 
385 	if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
386 		ret = of_genpd_add_provider_onecell(dev->of_node,
387 						    &imx_gpc_onecell_data);
388 		if (ret)
389 			goto genpd_err;
390 	}
391 
392 	return 0;
393 
394 genpd_err:
395 	for (i = 0; i < num_domains; i++)
396 		pm_genpd_remove(&imx_gpc_domains[i].base);
397 	imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
398 clk_err:
399 	return ret;
400 }
401 
402 static int imx_gpc_probe(struct platform_device *pdev)
403 {
404 	const struct imx_gpc_dt_data *of_id_data = device_get_match_data(&pdev->dev);
405 	struct device_node *pgc_node;
406 	struct regmap *regmap;
407 	void __iomem *base;
408 	int ret;
409 
410 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
411 
412 	/* bail out if DT too old and doesn't provide the necessary info */
413 	if (!of_property_present(pdev->dev.of_node, "#power-domain-cells") &&
414 	    !pgc_node)
415 		return 0;
416 
417 	base = devm_platform_ioremap_resource(pdev, 0);
418 	if (IS_ERR(base))
419 		return PTR_ERR(base);
420 
421 	regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
422 					   &imx_gpc_regmap_config);
423 	if (IS_ERR(regmap)) {
424 		ret = PTR_ERR(regmap);
425 		dev_err(&pdev->dev, "failed to init regmap: %d\n",
426 			ret);
427 		return ret;
428 	}
429 
430 	/*
431 	 * Disable PU power down by runtime PM if ERR009619 is present.
432 	 *
433 	 * The PRE clock will be paused for several cycles when turning on the
434 	 * PU domain LDO from power down state. If PRE is in use at that time,
435 	 * the IPU/PRG cannot get the correct display data from the PRE.
436 	 *
437 	 * This is not a concern when the whole system enters suspend state, so
438 	 * it's safe to power down PU in this case.
439 	 */
440 	if (of_id_data->err009619_present)
441 		imx_gpc_domains[GPC_PGC_DOMAIN_PU].base.flags |=
442 				GENPD_FLAG_RPM_ALWAYS_ON;
443 
444 	/* Keep DISP always on if ERR006287 is present */
445 	if (of_id_data->err006287_present)
446 		imx_gpc_domains[GPC_PGC_DOMAIN_DISPLAY].base.flags |=
447 				GENPD_FLAG_ALWAYS_ON;
448 
449 	if (!pgc_node) {
450 		ret = imx_gpc_old_dt_init(&pdev->dev, regmap,
451 					  of_id_data->num_domains);
452 		if (ret)
453 			return ret;
454 	} else {
455 		struct imx_pm_domain *domain;
456 		struct platform_device *pd_pdev;
457 		struct clk *ipg_clk;
458 		unsigned int ipg_rate_mhz;
459 		int domain_index;
460 
461 		ipg_clk = devm_clk_get(&pdev->dev, "ipg");
462 		if (IS_ERR(ipg_clk))
463 			return PTR_ERR(ipg_clk);
464 		ipg_rate_mhz = clk_get_rate(ipg_clk) / 1000000;
465 
466 		for_each_child_of_node_scoped(pgc_node, np) {
467 			ret = of_property_read_u32(np, "reg", &domain_index);
468 			if (ret)
469 				return ret;
470 
471 			if (domain_index >= of_id_data->num_domains)
472 				continue;
473 
474 			pd_pdev = platform_device_alloc("imx-pgc-power-domain",
475 							domain_index);
476 			if (!pd_pdev)
477 				return -ENOMEM;
478 
479 			ret = platform_device_add_data(pd_pdev,
480 						       &imx_gpc_domains[domain_index],
481 						       sizeof(imx_gpc_domains[domain_index]));
482 			if (ret) {
483 				platform_device_put(pd_pdev);
484 				return ret;
485 			}
486 			domain = pd_pdev->dev.platform_data;
487 			domain->regmap = regmap;
488 			domain->ipg_rate_mhz = ipg_rate_mhz;
489 
490 			pd_pdev->dev.parent = &pdev->dev;
491 			pd_pdev->dev.of_node = np;
492 			pd_pdev->dev.fwnode = of_fwnode_handle(np);
493 
494 			ret = platform_device_add(pd_pdev);
495 			if (ret) {
496 				platform_device_put(pd_pdev);
497 				return ret;
498 			}
499 		}
500 	}
501 
502 	return 0;
503 }
504 
505 static void imx_gpc_remove(struct platform_device *pdev)
506 {
507 	struct device_node *pgc_node;
508 	int ret;
509 
510 	pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
511 
512 	/* bail out if DT too old and doesn't provide the necessary info */
513 	if (!of_property_present(pdev->dev.of_node, "#power-domain-cells") &&
514 	    !pgc_node)
515 		return;
516 
517 	/*
518 	 * If the old DT binding is used the toplevel driver needs to
519 	 * de-register the power domains
520 	 */
521 	if (!pgc_node) {
522 		of_genpd_del_provider(pdev->dev.of_node);
523 
524 		ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base);
525 		if (ret) {
526 			dev_err(&pdev->dev, "Failed to remove PU power domain (%pe)\n",
527 				ERR_PTR(ret));
528 			return;
529 		}
530 		imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
531 
532 		ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base);
533 		if (ret) {
534 			dev_err(&pdev->dev, "Failed to remove ARM power domain (%pe)\n",
535 				ERR_PTR(ret));
536 			return;
537 		}
538 	}
539 }
540 
541 static struct platform_driver imx_gpc_driver = {
542 	.driver = {
543 		.name = "imx-gpc",
544 		.of_match_table = imx_gpc_dt_ids,
545 	},
546 	.probe = imx_gpc_probe,
547 	.remove = imx_gpc_remove,
548 };
549 builtin_platform_driver(imx_gpc_driver)
550