xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision 7bcae826)
1 /*
2  * Copyright 2011-2013 Freescale Semiconductor, Inc.
3  * Copyright 2011 Linaro Ltd.
4  *
5  * The code contained herein is licensed under the GNU General Public
6  * License. You may obtain a copy of the GNU General Public License
7  * Version 2 or later at the following locations:
8  *
9  * http://www.opensource.org/licenses/gpl-license.html
10  * http://www.gnu.org/copyleft/gpl.html
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/delay.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 #include <linux/irqchip.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 #include <linux/of_irq.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_domain.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/irqchip/arm-gic.h>
25 #include "common.h"
26 #include "hardware.h"
27 
28 #define GPC_CNTR		0x000
29 #define GPC_IMR1		0x008
30 #define GPC_PGC_GPU_PDN		0x260
31 #define GPC_PGC_GPU_PUPSCR	0x264
32 #define GPC_PGC_GPU_PDNSCR	0x268
33 #define GPC_PGC_CPU_PDN		0x2a0
34 #define GPC_PGC_CPU_PUPSCR	0x2a4
35 #define GPC_PGC_CPU_PDNSCR	0x2a8
36 #define GPC_PGC_SW2ISO_SHIFT	0x8
37 #define GPC_PGC_SW_SHIFT	0x0
38 
39 #define IMR_NUM			4
40 #define GPC_MAX_IRQS		(IMR_NUM * 32)
41 
42 #define GPU_VPU_PUP_REQ		BIT(1)
43 #define GPU_VPU_PDN_REQ		BIT(0)
44 
45 #define GPC_CLK_MAX		6
46 
47 struct pu_domain {
48 	struct generic_pm_domain base;
49 	struct regulator *reg;
50 	struct clk *clk[GPC_CLK_MAX];
51 	int num_clks;
52 };
53 
54 static void __iomem *gpc_base;
55 static u32 gpc_wake_irqs[IMR_NUM];
56 static u32 gpc_saved_imrs[IMR_NUM];
57 
58 void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw)
59 {
60 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
61 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PUPSCR);
62 }
63 
64 void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw)
65 {
66 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
67 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PDNSCR);
68 }
69 
70 void imx_gpc_set_arm_power_in_lpm(bool power_off)
71 {
72 	writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
73 }
74 
75 void imx_gpc_pre_suspend(bool arm_power_off)
76 {
77 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
78 	int i;
79 
80 	/* Tell GPC to power off ARM core when suspend */
81 	if (arm_power_off)
82 		imx_gpc_set_arm_power_in_lpm(arm_power_off);
83 
84 	for (i = 0; i < IMR_NUM; i++) {
85 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
86 		writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
87 	}
88 }
89 
90 void imx_gpc_post_resume(void)
91 {
92 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
93 	int i;
94 
95 	/* Keep ARM core powered on for other low-power modes */
96 	imx_gpc_set_arm_power_in_lpm(false);
97 
98 	for (i = 0; i < IMR_NUM; i++)
99 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
100 }
101 
102 static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
103 {
104 	unsigned int idx = d->hwirq / 32;
105 	u32 mask;
106 
107 	mask = 1 << d->hwirq % 32;
108 	gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
109 				  gpc_wake_irqs[idx] & ~mask;
110 
111 	/*
112 	 * Do *not* call into the parent, as the GIC doesn't have any
113 	 * wake-up facility...
114 	 */
115 	return 0;
116 }
117 
118 void imx_gpc_mask_all(void)
119 {
120 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
121 	int i;
122 
123 	for (i = 0; i < IMR_NUM; i++) {
124 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
125 		writel_relaxed(~0, reg_imr1 + i * 4);
126 	}
127 
128 }
129 
130 void imx_gpc_restore_all(void)
131 {
132 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
133 	int i;
134 
135 	for (i = 0; i < IMR_NUM; i++)
136 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
137 }
138 
139 void imx_gpc_hwirq_unmask(unsigned int hwirq)
140 {
141 	void __iomem *reg;
142 	u32 val;
143 
144 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
145 	val = readl_relaxed(reg);
146 	val &= ~(1 << hwirq % 32);
147 	writel_relaxed(val, reg);
148 }
149 
150 void imx_gpc_hwirq_mask(unsigned int hwirq)
151 {
152 	void __iomem *reg;
153 	u32 val;
154 
155 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
156 	val = readl_relaxed(reg);
157 	val |= 1 << (hwirq % 32);
158 	writel_relaxed(val, reg);
159 }
160 
161 static void imx_gpc_irq_unmask(struct irq_data *d)
162 {
163 	imx_gpc_hwirq_unmask(d->hwirq);
164 	irq_chip_unmask_parent(d);
165 }
166 
167 static void imx_gpc_irq_mask(struct irq_data *d)
168 {
169 	imx_gpc_hwirq_mask(d->hwirq);
170 	irq_chip_mask_parent(d);
171 }
172 
173 static struct irq_chip imx_gpc_chip = {
174 	.name			= "GPC",
175 	.irq_eoi		= irq_chip_eoi_parent,
176 	.irq_mask		= imx_gpc_irq_mask,
177 	.irq_unmask		= imx_gpc_irq_unmask,
178 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
179 	.irq_set_wake		= imx_gpc_irq_set_wake,
180 	.irq_set_type           = irq_chip_set_type_parent,
181 #ifdef CONFIG_SMP
182 	.irq_set_affinity	= irq_chip_set_affinity_parent,
183 #endif
184 };
185 
186 static int imx_gpc_domain_translate(struct irq_domain *d,
187 				    struct irq_fwspec *fwspec,
188 				    unsigned long *hwirq,
189 				    unsigned int *type)
190 {
191 	if (is_of_node(fwspec->fwnode)) {
192 		if (fwspec->param_count != 3)
193 			return -EINVAL;
194 
195 		/* No PPI should point to this domain */
196 		if (fwspec->param[0] != 0)
197 			return -EINVAL;
198 
199 		*hwirq = fwspec->param[1];
200 		*type = fwspec->param[2];
201 		return 0;
202 	}
203 
204 	return -EINVAL;
205 }
206 
207 static int imx_gpc_domain_alloc(struct irq_domain *domain,
208 				  unsigned int irq,
209 				  unsigned int nr_irqs, void *data)
210 {
211 	struct irq_fwspec *fwspec = data;
212 	struct irq_fwspec parent_fwspec;
213 	irq_hw_number_t hwirq;
214 	int i;
215 
216 	if (fwspec->param_count != 3)
217 		return -EINVAL;	/* Not GIC compliant */
218 	if (fwspec->param[0] != 0)
219 		return -EINVAL;	/* No PPI should point to this domain */
220 
221 	hwirq = fwspec->param[1];
222 	if (hwirq >= GPC_MAX_IRQS)
223 		return -EINVAL;	/* Can't deal with this */
224 
225 	for (i = 0; i < nr_irqs; i++)
226 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
227 					      &imx_gpc_chip, NULL);
228 
229 	parent_fwspec = *fwspec;
230 	parent_fwspec.fwnode = domain->parent->fwnode;
231 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
232 					    &parent_fwspec);
233 }
234 
235 static const struct irq_domain_ops imx_gpc_domain_ops = {
236 	.translate	= imx_gpc_domain_translate,
237 	.alloc		= imx_gpc_domain_alloc,
238 	.free		= irq_domain_free_irqs_common,
239 };
240 
241 static int __init imx_gpc_init(struct device_node *node,
242 			       struct device_node *parent)
243 {
244 	struct irq_domain *parent_domain, *domain;
245 	int i;
246 
247 	if (!parent) {
248 		pr_err("%s: no parent, giving up\n", node->full_name);
249 		return -ENODEV;
250 	}
251 
252 	parent_domain = irq_find_host(parent);
253 	if (!parent_domain) {
254 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
255 		return -ENXIO;
256 	}
257 
258 	gpc_base = of_iomap(node, 0);
259 	if (WARN_ON(!gpc_base))
260 	        return -ENOMEM;
261 
262 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
263 					  node, &imx_gpc_domain_ops,
264 					  NULL);
265 	if (!domain) {
266 		iounmap(gpc_base);
267 		return -ENOMEM;
268 	}
269 
270 	/* Initially mask all interrupts */
271 	for (i = 0; i < IMR_NUM; i++)
272 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
273 
274 	/*
275 	 * Clear the OF_POPULATED flag set in of_irq_init so that
276 	 * later the GPC power domain driver will not be skipped.
277 	 */
278 	of_node_clear_flag(node, OF_POPULATED);
279 
280 	return 0;
281 }
282 IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
283 
284 void __init imx_gpc_check_dt(void)
285 {
286 	struct device_node *np;
287 
288 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
289 	if (WARN_ON(!np))
290 		return;
291 
292 	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
293 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
294 
295 		/* map GPC, so that at least CPUidle and WARs keep working */
296 		gpc_base = of_iomap(np, 0);
297 	}
298 }
299 
300 static void _imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
301 {
302 	int iso, iso2sw;
303 	u32 val;
304 
305 	/* Read ISO and ISO2SW power down delays */
306 	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PDNSCR);
307 	iso = val & 0x3f;
308 	iso2sw = (val >> 8) & 0x3f;
309 
310 	/* Gate off PU domain when GPU/VPU when powered down */
311 	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
312 
313 	/* Request GPC to power down GPU/VPU */
314 	val = readl_relaxed(gpc_base + GPC_CNTR);
315 	val |= GPU_VPU_PDN_REQ;
316 	writel_relaxed(val, gpc_base + GPC_CNTR);
317 
318 	/* Wait ISO + ISO2SW IPG clock cycles */
319 	ndelay((iso + iso2sw) * 1000 / 66);
320 }
321 
322 static int imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
323 {
324 	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
325 
326 	_imx6q_pm_pu_power_off(genpd);
327 
328 	if (pu->reg)
329 		regulator_disable(pu->reg);
330 
331 	return 0;
332 }
333 
334 static int imx6q_pm_pu_power_on(struct generic_pm_domain *genpd)
335 {
336 	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
337 	int i, ret, sw, sw2iso;
338 	u32 val;
339 
340 	if (pu->reg)
341 		ret = regulator_enable(pu->reg);
342 	if (pu->reg && ret) {
343 		pr_err("%s: failed to enable regulator: %d\n", __func__, ret);
344 		return ret;
345 	}
346 
347 	/* Enable reset clocks for all devices in the PU domain */
348 	for (i = 0; i < pu->num_clks; i++)
349 		clk_prepare_enable(pu->clk[i]);
350 
351 	/* Gate off PU domain when GPU/VPU when powered down */
352 	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
353 
354 	/* Read ISO and ISO2SW power down delays */
355 	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PUPSCR);
356 	sw = val & 0x3f;
357 	sw2iso = (val >> 8) & 0x3f;
358 
359 	/* Request GPC to power up GPU/VPU */
360 	val = readl_relaxed(gpc_base + GPC_CNTR);
361 	val |= GPU_VPU_PUP_REQ;
362 	writel_relaxed(val, gpc_base + GPC_CNTR);
363 
364 	/* Wait ISO + ISO2SW IPG clock cycles */
365 	ndelay((sw + sw2iso) * 1000 / 66);
366 
367 	/* Disable reset clocks for all devices in the PU domain */
368 	for (i = 0; i < pu->num_clks; i++)
369 		clk_disable_unprepare(pu->clk[i]);
370 
371 	return 0;
372 }
373 
374 static struct generic_pm_domain imx6q_arm_domain = {
375 	.name = "ARM",
376 };
377 
378 static struct pu_domain imx6q_pu_domain = {
379 	.base = {
380 		.name = "PU",
381 		.power_off = imx6q_pm_pu_power_off,
382 		.power_on = imx6q_pm_pu_power_on,
383 	},
384 };
385 
386 static struct generic_pm_domain imx6sl_display_domain = {
387 	.name = "DISPLAY",
388 };
389 
390 static struct generic_pm_domain *imx_gpc_domains[] = {
391 	&imx6q_arm_domain,
392 	&imx6q_pu_domain.base,
393 	&imx6sl_display_domain,
394 };
395 
396 static struct genpd_onecell_data imx_gpc_onecell_data = {
397 	.domains = imx_gpc_domains,
398 	.num_domains = ARRAY_SIZE(imx_gpc_domains),
399 };
400 
401 static int imx_gpc_genpd_init(struct device *dev, struct regulator *pu_reg)
402 {
403 	struct clk *clk;
404 	int i, ret;
405 
406 	imx6q_pu_domain.reg = pu_reg;
407 
408 	for (i = 0; ; i++) {
409 		clk = of_clk_get(dev->of_node, i);
410 		if (IS_ERR(clk))
411 			break;
412 		if (i >= GPC_CLK_MAX) {
413 			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
414 			goto clk_err;
415 		}
416 		imx6q_pu_domain.clk[i] = clk;
417 	}
418 	imx6q_pu_domain.num_clks = i;
419 
420 	/* Enable power always in case bootloader disabled it. */
421 	imx6q_pm_pu_power_on(&imx6q_pu_domain.base);
422 
423 	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
424 		return 0;
425 
426 	imx6q_pu_domain.base.states = devm_kzalloc(dev,
427 					sizeof(*imx6q_pu_domain.base.states),
428 					GFP_KERNEL);
429 	if (!imx6q_pu_domain.base.states)
430 		return -ENOMEM;
431 
432 	imx6q_pu_domain.base.states[0].power_off_latency_ns = 25000;
433 	imx6q_pu_domain.base.states[0].power_on_latency_ns = 2000000;
434 	imx6q_pu_domain.base.state_count = 1;
435 
436 	for (i = 0; i < ARRAY_SIZE(imx_gpc_domains); i++)
437 		pm_genpd_init(imx_gpc_domains[i], NULL, false);
438 
439 	ret =  of_genpd_add_provider_onecell(dev->of_node,
440 					     &imx_gpc_onecell_data);
441 	if (ret)
442 		goto power_off;
443 
444 	return 0;
445 
446 power_off:
447 	imx6q_pm_pu_power_off(&imx6q_pu_domain.base);
448 clk_err:
449 	while (i--)
450 		clk_put(imx6q_pu_domain.clk[i]);
451 	imx6q_pu_domain.reg = NULL;
452 	return -EINVAL;
453 }
454 
455 static int imx_gpc_probe(struct platform_device *pdev)
456 {
457 	struct regulator *pu_reg;
458 	int ret;
459 
460 	/* bail out if DT too old and doesn't provide the necessary info */
461 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells"))
462 		return 0;
463 
464 	pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
465 	if (PTR_ERR(pu_reg) == -ENODEV)
466 		pu_reg = NULL;
467 	if (IS_ERR(pu_reg)) {
468 		ret = PTR_ERR(pu_reg);
469 		dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret);
470 		return ret;
471 	}
472 
473 	return imx_gpc_genpd_init(&pdev->dev, pu_reg);
474 }
475 
476 static const struct of_device_id imx_gpc_dt_ids[] = {
477 	{ .compatible = "fsl,imx6q-gpc" },
478 	{ .compatible = "fsl,imx6sl-gpc" },
479 	{ }
480 };
481 
482 static struct platform_driver imx_gpc_driver = {
483 	.driver = {
484 		.name = "imx-gpc",
485 		.of_match_table = imx_gpc_dt_ids,
486 	},
487 	.probe = imx_gpc_probe,
488 };
489 
490 static int __init imx_pgc_init(void)
491 {
492 	return platform_driver_register(&imx_gpc_driver);
493 }
494 subsys_initcall(imx_pgc_init);
495