xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision 827634ad)
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_xlate(struct irq_domain *domain,
185 				struct device_node *controller,
186 				const u32 *intspec,
187 				unsigned int intsize,
188 				unsigned long *out_hwirq,
189 				unsigned int *out_type)
190 {
191 	if (domain->of_node != controller)
192 		return -EINVAL;	/* Shouldn't happen, really... */
193 	if (intsize != 3)
194 		return -EINVAL;	/* Not GIC compliant */
195 	if (intspec[0] != 0)
196 		return -EINVAL;	/* No PPI should point to this domain */
197 
198 	*out_hwirq = intspec[1];
199 	*out_type = intspec[2];
200 	return 0;
201 }
202 
203 static int imx_gpc_domain_alloc(struct irq_domain *domain,
204 				  unsigned int irq,
205 				  unsigned int nr_irqs, void *data)
206 {
207 	struct of_phandle_args *args = data;
208 	struct of_phandle_args parent_args;
209 	irq_hw_number_t hwirq;
210 	int i;
211 
212 	if (args->args_count != 3)
213 		return -EINVAL;	/* Not GIC compliant */
214 	if (args->args[0] != 0)
215 		return -EINVAL;	/* No PPI should point to this domain */
216 
217 	hwirq = args->args[1];
218 	if (hwirq >= GPC_MAX_IRQS)
219 		return -EINVAL;	/* Can't deal with this */
220 
221 	for (i = 0; i < nr_irqs; i++)
222 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
223 					      &imx_gpc_chip, NULL);
224 
225 	parent_args = *args;
226 	parent_args.np = domain->parent->of_node;
227 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs, &parent_args);
228 }
229 
230 static struct irq_domain_ops imx_gpc_domain_ops = {
231 	.xlate	= imx_gpc_domain_xlate,
232 	.alloc	= imx_gpc_domain_alloc,
233 	.free	= irq_domain_free_irqs_common,
234 };
235 
236 static int __init imx_gpc_init(struct device_node *node,
237 			       struct device_node *parent)
238 {
239 	struct irq_domain *parent_domain, *domain;
240 	int i;
241 
242 	if (!parent) {
243 		pr_err("%s: no parent, giving up\n", node->full_name);
244 		return -ENODEV;
245 	}
246 
247 	parent_domain = irq_find_host(parent);
248 	if (!parent_domain) {
249 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
250 		return -ENXIO;
251 	}
252 
253 	gpc_base = of_iomap(node, 0);
254 	if (WARN_ON(!gpc_base))
255 	        return -ENOMEM;
256 
257 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
258 					  node, &imx_gpc_domain_ops,
259 					  NULL);
260 	if (!domain) {
261 		iounmap(gpc_base);
262 		return -ENOMEM;
263 	}
264 
265 	/* Initially mask all interrupts */
266 	for (i = 0; i < IMR_NUM; i++)
267 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
268 
269 	return 0;
270 }
271 
272 /*
273  * We cannot use the IRQCHIP_DECLARE macro that lives in
274  * drivers/irqchip, so we're forced to roll our own. Not very nice.
275  */
276 OF_DECLARE_2(irqchip, imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
277 
278 void __init imx_gpc_check_dt(void)
279 {
280 	struct device_node *np;
281 
282 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
283 	if (WARN_ON(!np ||
284 		    !of_find_property(np, "interrupt-controller", NULL)))
285 		pr_warn("Outdated DT detected, system is about to crash!!!\n");
286 }
287 
288 #ifdef CONFIG_PM_GENERIC_DOMAINS
289 
290 static void _imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
291 {
292 	int iso, iso2sw;
293 	u32 val;
294 
295 	/* Read ISO and ISO2SW power down delays */
296 	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PDNSCR);
297 	iso = val & 0x3f;
298 	iso2sw = (val >> 8) & 0x3f;
299 
300 	/* Gate off PU domain when GPU/VPU when powered down */
301 	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
302 
303 	/* Request GPC to power down GPU/VPU */
304 	val = readl_relaxed(gpc_base + GPC_CNTR);
305 	val |= GPU_VPU_PDN_REQ;
306 	writel_relaxed(val, gpc_base + GPC_CNTR);
307 
308 	/* Wait ISO + ISO2SW IPG clock cycles */
309 	ndelay((iso + iso2sw) * 1000 / 66);
310 }
311 
312 static int imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
313 {
314 	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
315 
316 	_imx6q_pm_pu_power_off(genpd);
317 
318 	if (pu->reg)
319 		regulator_disable(pu->reg);
320 
321 	return 0;
322 }
323 
324 static int imx6q_pm_pu_power_on(struct generic_pm_domain *genpd)
325 {
326 	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
327 	int i, ret, sw, sw2iso;
328 	u32 val;
329 
330 	if (pu->reg)
331 		ret = regulator_enable(pu->reg);
332 	if (pu->reg && ret) {
333 		pr_err("%s: failed to enable regulator: %d\n", __func__, ret);
334 		return ret;
335 	}
336 
337 	/* Enable reset clocks for all devices in the PU domain */
338 	for (i = 0; i < pu->num_clks; i++)
339 		clk_prepare_enable(pu->clk[i]);
340 
341 	/* Gate off PU domain when GPU/VPU when powered down */
342 	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
343 
344 	/* Read ISO and ISO2SW power down delays */
345 	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PUPSCR);
346 	sw = val & 0x3f;
347 	sw2iso = (val >> 8) & 0x3f;
348 
349 	/* Request GPC to power up GPU/VPU */
350 	val = readl_relaxed(gpc_base + GPC_CNTR);
351 	val |= GPU_VPU_PUP_REQ;
352 	writel_relaxed(val, gpc_base + GPC_CNTR);
353 
354 	/* Wait ISO + ISO2SW IPG clock cycles */
355 	ndelay((sw + sw2iso) * 1000 / 66);
356 
357 	/* Disable reset clocks for all devices in the PU domain */
358 	for (i = 0; i < pu->num_clks; i++)
359 		clk_disable_unprepare(pu->clk[i]);
360 
361 	return 0;
362 }
363 
364 static struct generic_pm_domain imx6q_arm_domain = {
365 	.name = "ARM",
366 };
367 
368 static struct pu_domain imx6q_pu_domain = {
369 	.base = {
370 		.name = "PU",
371 		.power_off = imx6q_pm_pu_power_off,
372 		.power_on = imx6q_pm_pu_power_on,
373 		.power_off_latency_ns = 25000,
374 		.power_on_latency_ns = 2000000,
375 	},
376 };
377 
378 static struct generic_pm_domain imx6sl_display_domain = {
379 	.name = "DISPLAY",
380 };
381 
382 static struct generic_pm_domain *imx_gpc_domains[] = {
383 	&imx6q_arm_domain,
384 	&imx6q_pu_domain.base,
385 	&imx6sl_display_domain,
386 };
387 
388 static struct genpd_onecell_data imx_gpc_onecell_data = {
389 	.domains = imx_gpc_domains,
390 	.num_domains = ARRAY_SIZE(imx_gpc_domains),
391 };
392 
393 static int imx_gpc_genpd_init(struct device *dev, struct regulator *pu_reg)
394 {
395 	struct clk *clk;
396 	bool is_off;
397 	int i;
398 
399 	imx6q_pu_domain.reg = pu_reg;
400 
401 	for (i = 0; ; i++) {
402 		clk = of_clk_get(dev->of_node, i);
403 		if (IS_ERR(clk))
404 			break;
405 		if (i >= GPC_CLK_MAX) {
406 			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
407 			goto clk_err;
408 		}
409 		imx6q_pu_domain.clk[i] = clk;
410 	}
411 	imx6q_pu_domain.num_clks = i;
412 
413 	is_off = IS_ENABLED(CONFIG_PM);
414 	if (is_off) {
415 		_imx6q_pm_pu_power_off(&imx6q_pu_domain.base);
416 	} else {
417 		/*
418 		 * Enable power if compiled without CONFIG_PM in case the
419 		 * bootloader disabled it.
420 		 */
421 		imx6q_pm_pu_power_on(&imx6q_pu_domain.base);
422 	}
423 
424 	pm_genpd_init(&imx6q_pu_domain.base, NULL, is_off);
425 	return of_genpd_add_provider_onecell(dev->of_node,
426 					     &imx_gpc_onecell_data);
427 
428 clk_err:
429 	while (i--)
430 		clk_put(imx6q_pu_domain.clk[i]);
431 	return -EINVAL;
432 }
433 
434 #else
435 static inline int imx_gpc_genpd_init(struct device *dev, struct regulator *reg)
436 {
437 	return 0;
438 }
439 #endif /* CONFIG_PM_GENERIC_DOMAINS */
440 
441 static int imx_gpc_probe(struct platform_device *pdev)
442 {
443 	struct regulator *pu_reg;
444 	int ret;
445 
446 	pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
447 	if (PTR_ERR(pu_reg) == -ENODEV)
448 		pu_reg = NULL;
449 	if (IS_ERR(pu_reg)) {
450 		ret = PTR_ERR(pu_reg);
451 		dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret);
452 		return ret;
453 	}
454 
455 	return imx_gpc_genpd_init(&pdev->dev, pu_reg);
456 }
457 
458 static const struct of_device_id imx_gpc_dt_ids[] = {
459 	{ .compatible = "fsl,imx6q-gpc" },
460 	{ .compatible = "fsl,imx6sl-gpc" },
461 	{ }
462 };
463 
464 static struct platform_driver imx_gpc_driver = {
465 	.driver = {
466 		.name = "imx-gpc",
467 		.owner = THIS_MODULE,
468 		.of_match_table = imx_gpc_dt_ids,
469 	},
470 	.probe = imx_gpc_probe,
471 };
472 
473 static int __init imx_pgc_init(void)
474 {
475 	return platform_driver_register(&imx_gpc_driver);
476 }
477 subsys_initcall(imx_pgc_init);
478