xref: /linux/arch/arm/mach-imx/gpc.c (revision 6aa2fdb87cf01d7746955c600cbac352dc04d451)
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/of.h>
18 #include <linux/of_address.h>
19 #include <linux/of_irq.h>
20 #include <linux/platform_device.h>
21 #include <linux/pm_domain.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/irqchip/arm-gic.h>
24 #include "common.h"
25 #include "hardware.h"
26 
27 #define GPC_CNTR		0x000
28 #define GPC_IMR1		0x008
29 #define GPC_PGC_GPU_PDN		0x260
30 #define GPC_PGC_GPU_PUPSCR	0x264
31 #define GPC_PGC_GPU_PDNSCR	0x268
32 #define GPC_PGC_CPU_PDN		0x2a0
33 #define GPC_PGC_CPU_PUPSCR	0x2a4
34 #define GPC_PGC_CPU_PDNSCR	0x2a8
35 #define GPC_PGC_SW2ISO_SHIFT	0x8
36 #define GPC_PGC_SW_SHIFT	0x0
37 
38 #define IMR_NUM			4
39 #define GPC_MAX_IRQS		(IMR_NUM * 32)
40 
41 #define GPU_VPU_PUP_REQ		BIT(1)
42 #define GPU_VPU_PDN_REQ		BIT(0)
43 
44 #define GPC_CLK_MAX		6
45 
46 struct pu_domain {
47 	struct generic_pm_domain base;
48 	struct regulator *reg;
49 	struct clk *clk[GPC_CLK_MAX];
50 	int num_clks;
51 };
52 
53 static void __iomem *gpc_base;
54 static u32 gpc_wake_irqs[IMR_NUM];
55 static u32 gpc_saved_imrs[IMR_NUM];
56 
57 void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw)
58 {
59 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
60 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PUPSCR);
61 }
62 
63 void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw)
64 {
65 	writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
66 		(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PDNSCR);
67 }
68 
69 void imx_gpc_set_arm_power_in_lpm(bool power_off)
70 {
71 	writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
72 }
73 
74 void imx_gpc_pre_suspend(bool arm_power_off)
75 {
76 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
77 	int i;
78 
79 	/* Tell GPC to power off ARM core when suspend */
80 	if (arm_power_off)
81 		imx_gpc_set_arm_power_in_lpm(arm_power_off);
82 
83 	for (i = 0; i < IMR_NUM; i++) {
84 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
85 		writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
86 	}
87 }
88 
89 void imx_gpc_post_resume(void)
90 {
91 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
92 	int i;
93 
94 	/* Keep ARM core powered on for other low-power modes */
95 	imx_gpc_set_arm_power_in_lpm(false);
96 
97 	for (i = 0; i < IMR_NUM; i++)
98 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
99 }
100 
101 static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
102 {
103 	unsigned int idx = d->hwirq / 32;
104 	u32 mask;
105 
106 	mask = 1 << d->hwirq % 32;
107 	gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
108 				  gpc_wake_irqs[idx] & ~mask;
109 
110 	/*
111 	 * Do *not* call into the parent, as the GIC doesn't have any
112 	 * wake-up facility...
113 	 */
114 	return 0;
115 }
116 
117 void imx_gpc_mask_all(void)
118 {
119 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
120 	int i;
121 
122 	for (i = 0; i < IMR_NUM; i++) {
123 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
124 		writel_relaxed(~0, reg_imr1 + i * 4);
125 	}
126 
127 }
128 
129 void imx_gpc_restore_all(void)
130 {
131 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
132 	int i;
133 
134 	for (i = 0; i < IMR_NUM; i++)
135 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
136 }
137 
138 void imx_gpc_hwirq_unmask(unsigned int hwirq)
139 {
140 	void __iomem *reg;
141 	u32 val;
142 
143 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
144 	val = readl_relaxed(reg);
145 	val &= ~(1 << hwirq % 32);
146 	writel_relaxed(val, reg);
147 }
148 
149 void imx_gpc_hwirq_mask(unsigned int hwirq)
150 {
151 	void __iomem *reg;
152 	u32 val;
153 
154 	reg = gpc_base + GPC_IMR1 + hwirq / 32 * 4;
155 	val = readl_relaxed(reg);
156 	val |= 1 << (hwirq % 32);
157 	writel_relaxed(val, reg);
158 }
159 
160 static void imx_gpc_irq_unmask(struct irq_data *d)
161 {
162 	imx_gpc_hwirq_unmask(d->hwirq);
163 	irq_chip_unmask_parent(d);
164 }
165 
166 static void imx_gpc_irq_mask(struct irq_data *d)
167 {
168 	imx_gpc_hwirq_mask(d->hwirq);
169 	irq_chip_mask_parent(d);
170 }
171 
172 static struct irq_chip imx_gpc_chip = {
173 	.name			= "GPC",
174 	.irq_eoi		= irq_chip_eoi_parent,
175 	.irq_mask		= imx_gpc_irq_mask,
176 	.irq_unmask		= imx_gpc_irq_unmask,
177 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
178 	.irq_set_wake		= imx_gpc_irq_set_wake,
179 #ifdef CONFIG_SMP
180 	.irq_set_affinity	= irq_chip_set_affinity_parent,
181 #endif
182 };
183 
184 static int imx_gpc_domain_translate(struct irq_domain *d,
185 				    struct irq_fwspec *fwspec,
186 				    unsigned long *hwirq,
187 				    unsigned int *type)
188 {
189 	if (is_of_node(fwspec->fwnode)) {
190 		if (fwspec->param_count != 3)
191 			return -EINVAL;
192 
193 		/* No PPI should point to this domain */
194 		if (fwspec->param[0] != 0)
195 			return -EINVAL;
196 
197 		*hwirq = fwspec->param[1];
198 		*type = fwspec->param[2];
199 		return 0;
200 	}
201 
202 	return -EINVAL;
203 }
204 
205 static int imx_gpc_domain_alloc(struct irq_domain *domain,
206 				  unsigned int irq,
207 				  unsigned int nr_irqs, void *data)
208 {
209 	struct irq_fwspec *fwspec = data;
210 	struct irq_fwspec parent_fwspec;
211 	irq_hw_number_t hwirq;
212 	int i;
213 
214 	if (fwspec->param_count != 3)
215 		return -EINVAL;	/* Not GIC compliant */
216 	if (fwspec->param[0] != 0)
217 		return -EINVAL;	/* No PPI should point to this domain */
218 
219 	hwirq = fwspec->param[1];
220 	if (hwirq >= GPC_MAX_IRQS)
221 		return -EINVAL;	/* Can't deal with this */
222 
223 	for (i = 0; i < nr_irqs; i++)
224 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
225 					      &imx_gpc_chip, NULL);
226 
227 	parent_fwspec = *fwspec;
228 	parent_fwspec.fwnode = domain->parent->fwnode;
229 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
230 					    &parent_fwspec);
231 }
232 
233 static const struct irq_domain_ops imx_gpc_domain_ops = {
234 	.translate	= imx_gpc_domain_translate,
235 	.alloc		= imx_gpc_domain_alloc,
236 	.free		= irq_domain_free_irqs_common,
237 };
238 
239 static int __init imx_gpc_init(struct device_node *node,
240 			       struct device_node *parent)
241 {
242 	struct irq_domain *parent_domain, *domain;
243 	int i;
244 
245 	if (!parent) {
246 		pr_err("%s: no parent, giving up\n", node->full_name);
247 		return -ENODEV;
248 	}
249 
250 	parent_domain = irq_find_host(parent);
251 	if (!parent_domain) {
252 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
253 		return -ENXIO;
254 	}
255 
256 	gpc_base = of_iomap(node, 0);
257 	if (WARN_ON(!gpc_base))
258 	        return -ENOMEM;
259 
260 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
261 					  node, &imx_gpc_domain_ops,
262 					  NULL);
263 	if (!domain) {
264 		iounmap(gpc_base);
265 		return -ENOMEM;
266 	}
267 
268 	/* Initially mask all interrupts */
269 	for (i = 0; i < IMR_NUM; i++)
270 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
271 
272 	return 0;
273 }
274 
275 /*
276  * We cannot use the IRQCHIP_DECLARE macro that lives in
277  * drivers/irqchip, so we're forced to roll our own. Not very nice.
278  */
279 OF_DECLARE_2(irqchip, imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
280 
281 void __init imx_gpc_check_dt(void)
282 {
283 	struct device_node *np;
284 
285 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
286 	if (WARN_ON(!np))
287 		return;
288 
289 	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
290 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
291 
292 		/* map GPC, so that at least CPUidle and WARs keep working */
293 		gpc_base = of_iomap(np, 0);
294 	}
295 }
296 
297 static void _imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
298 {
299 	int iso, iso2sw;
300 	u32 val;
301 
302 	/* Read ISO and ISO2SW power down delays */
303 	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PDNSCR);
304 	iso = val & 0x3f;
305 	iso2sw = (val >> 8) & 0x3f;
306 
307 	/* Gate off PU domain when GPU/VPU when powered down */
308 	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
309 
310 	/* Request GPC to power down GPU/VPU */
311 	val = readl_relaxed(gpc_base + GPC_CNTR);
312 	val |= GPU_VPU_PDN_REQ;
313 	writel_relaxed(val, gpc_base + GPC_CNTR);
314 
315 	/* Wait ISO + ISO2SW IPG clock cycles */
316 	ndelay((iso + iso2sw) * 1000 / 66);
317 }
318 
319 static int imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
320 {
321 	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
322 
323 	_imx6q_pm_pu_power_off(genpd);
324 
325 	if (pu->reg)
326 		regulator_disable(pu->reg);
327 
328 	return 0;
329 }
330 
331 static int imx6q_pm_pu_power_on(struct generic_pm_domain *genpd)
332 {
333 	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
334 	int i, ret, sw, sw2iso;
335 	u32 val;
336 
337 	if (pu->reg)
338 		ret = regulator_enable(pu->reg);
339 	if (pu->reg && ret) {
340 		pr_err("%s: failed to enable regulator: %d\n", __func__, ret);
341 		return ret;
342 	}
343 
344 	/* Enable reset clocks for all devices in the PU domain */
345 	for (i = 0; i < pu->num_clks; i++)
346 		clk_prepare_enable(pu->clk[i]);
347 
348 	/* Gate off PU domain when GPU/VPU when powered down */
349 	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
350 
351 	/* Read ISO and ISO2SW power down delays */
352 	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PUPSCR);
353 	sw = val & 0x3f;
354 	sw2iso = (val >> 8) & 0x3f;
355 
356 	/* Request GPC to power up GPU/VPU */
357 	val = readl_relaxed(gpc_base + GPC_CNTR);
358 	val |= GPU_VPU_PUP_REQ;
359 	writel_relaxed(val, gpc_base + GPC_CNTR);
360 
361 	/* Wait ISO + ISO2SW IPG clock cycles */
362 	ndelay((sw + sw2iso) * 1000 / 66);
363 
364 	/* Disable reset clocks for all devices in the PU domain */
365 	for (i = 0; i < pu->num_clks; i++)
366 		clk_disable_unprepare(pu->clk[i]);
367 
368 	return 0;
369 }
370 
371 static struct generic_pm_domain imx6q_arm_domain = {
372 	.name = "ARM",
373 };
374 
375 static struct pu_domain imx6q_pu_domain = {
376 	.base = {
377 		.name = "PU",
378 		.power_off = imx6q_pm_pu_power_off,
379 		.power_on = imx6q_pm_pu_power_on,
380 		.power_off_latency_ns = 25000,
381 		.power_on_latency_ns = 2000000,
382 	},
383 };
384 
385 static struct generic_pm_domain imx6sl_display_domain = {
386 	.name = "DISPLAY",
387 };
388 
389 static struct generic_pm_domain *imx_gpc_domains[] = {
390 	&imx6q_arm_domain,
391 	&imx6q_pu_domain.base,
392 	&imx6sl_display_domain,
393 };
394 
395 static struct genpd_onecell_data imx_gpc_onecell_data = {
396 	.domains = imx_gpc_domains,
397 	.num_domains = ARRAY_SIZE(imx_gpc_domains),
398 };
399 
400 static int imx_gpc_genpd_init(struct device *dev, struct regulator *pu_reg)
401 {
402 	struct clk *clk;
403 	int i;
404 
405 	imx6q_pu_domain.reg = pu_reg;
406 
407 	for (i = 0; ; i++) {
408 		clk = of_clk_get(dev->of_node, i);
409 		if (IS_ERR(clk))
410 			break;
411 		if (i >= GPC_CLK_MAX) {
412 			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
413 			goto clk_err;
414 		}
415 		imx6q_pu_domain.clk[i] = clk;
416 	}
417 	imx6q_pu_domain.num_clks = i;
418 
419 	/* Enable power always in case bootloader disabled it. */
420 	imx6q_pm_pu_power_on(&imx6q_pu_domain.base);
421 
422 	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
423 		return 0;
424 
425 	pm_genpd_init(&imx6q_pu_domain.base, NULL, false);
426 	return of_genpd_add_provider_onecell(dev->of_node,
427 					     &imx_gpc_onecell_data);
428 
429 clk_err:
430 	while (i--)
431 		clk_put(imx6q_pu_domain.clk[i]);
432 	return -EINVAL;
433 }
434 
435 static int imx_gpc_probe(struct platform_device *pdev)
436 {
437 	struct regulator *pu_reg;
438 	int ret;
439 
440 	/* bail out if DT too old and doesn't provide the necessary info */
441 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells"))
442 		return 0;
443 
444 	pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
445 	if (PTR_ERR(pu_reg) == -ENODEV)
446 		pu_reg = NULL;
447 	if (IS_ERR(pu_reg)) {
448 		ret = PTR_ERR(pu_reg);
449 		dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret);
450 		return ret;
451 	}
452 
453 	return imx_gpc_genpd_init(&pdev->dev, pu_reg);
454 }
455 
456 static const struct of_device_id imx_gpc_dt_ids[] = {
457 	{ .compatible = "fsl,imx6q-gpc" },
458 	{ .compatible = "fsl,imx6sl-gpc" },
459 	{ }
460 };
461 
462 static struct platform_driver imx_gpc_driver = {
463 	.driver = {
464 		.name = "imx-gpc",
465 		.of_match_table = imx_gpc_dt_ids,
466 	},
467 	.probe = imx_gpc_probe,
468 };
469 
470 static int __init imx_pgc_init(void)
471 {
472 	return platform_driver_register(&imx_gpc_driver);
473 }
474 subsys_initcall(imx_pgc_init);
475