xref: /openbmc/linux/arch/arm/mach-imx/gpc.c (revision b96fc2f3)
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 #ifdef CONFIG_SMP
181 	.irq_set_affinity	= irq_chip_set_affinity_parent,
182 #endif
183 };
184 
185 static int imx_gpc_domain_xlate(struct irq_domain *domain,
186 				struct device_node *controller,
187 				const u32 *intspec,
188 				unsigned int intsize,
189 				unsigned long *out_hwirq,
190 				unsigned int *out_type)
191 {
192 	if (domain->of_node != controller)
193 		return -EINVAL;	/* Shouldn't happen, really... */
194 	if (intsize != 3)
195 		return -EINVAL;	/* Not GIC compliant */
196 	if (intspec[0] != 0)
197 		return -EINVAL;	/* No PPI should point to this domain */
198 
199 	*out_hwirq = intspec[1];
200 	*out_type = intspec[2];
201 	return 0;
202 }
203 
204 static int imx_gpc_domain_alloc(struct irq_domain *domain,
205 				  unsigned int irq,
206 				  unsigned int nr_irqs, void *data)
207 {
208 	struct of_phandle_args *args = data;
209 	struct of_phandle_args parent_args;
210 	irq_hw_number_t hwirq;
211 	int i;
212 
213 	if (args->args_count != 3)
214 		return -EINVAL;	/* Not GIC compliant */
215 	if (args->args[0] != 0)
216 		return -EINVAL;	/* No PPI should point to this domain */
217 
218 	hwirq = args->args[1];
219 	if (hwirq >= GPC_MAX_IRQS)
220 		return -EINVAL;	/* Can't deal with this */
221 
222 	for (i = 0; i < nr_irqs; i++)
223 		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
224 					      &imx_gpc_chip, NULL);
225 
226 	parent_args = *args;
227 	parent_args.np = domain->parent->of_node;
228 	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs, &parent_args);
229 }
230 
231 static const struct irq_domain_ops imx_gpc_domain_ops = {
232 	.xlate	= imx_gpc_domain_xlate,
233 	.alloc	= imx_gpc_domain_alloc,
234 	.free	= irq_domain_free_irqs_common,
235 };
236 
237 static int __init imx_gpc_init(struct device_node *node,
238 			       struct device_node *parent)
239 {
240 	struct irq_domain *parent_domain, *domain;
241 	int i;
242 
243 	if (!parent) {
244 		pr_err("%s: no parent, giving up\n", node->full_name);
245 		return -ENODEV;
246 	}
247 
248 	parent_domain = irq_find_host(parent);
249 	if (!parent_domain) {
250 		pr_err("%s: unable to obtain parent domain\n", node->full_name);
251 		return -ENXIO;
252 	}
253 
254 	gpc_base = of_iomap(node, 0);
255 	if (WARN_ON(!gpc_base))
256 	        return -ENOMEM;
257 
258 	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
259 					  node, &imx_gpc_domain_ops,
260 					  NULL);
261 	if (!domain) {
262 		iounmap(gpc_base);
263 		return -ENOMEM;
264 	}
265 
266 	/* Initially mask all interrupts */
267 	for (i = 0; i < IMR_NUM; i++)
268 		writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
269 
270 	return 0;
271 }
272 IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
273 
274 void __init imx_gpc_check_dt(void)
275 {
276 	struct device_node *np;
277 
278 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
279 	if (WARN_ON(!np))
280 		return;
281 
282 	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
283 		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
284 
285 		/* map GPC, so that at least CPUidle and WARs keep working */
286 		gpc_base = of_iomap(np, 0);
287 	}
288 }
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 	int i;
397 
398 	imx6q_pu_domain.reg = pu_reg;
399 
400 	for (i = 0; ; i++) {
401 		clk = of_clk_get(dev->of_node, i);
402 		if (IS_ERR(clk))
403 			break;
404 		if (i >= GPC_CLK_MAX) {
405 			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
406 			goto clk_err;
407 		}
408 		imx6q_pu_domain.clk[i] = clk;
409 	}
410 	imx6q_pu_domain.num_clks = i;
411 
412 	/* Enable power always in case bootloader disabled it. */
413 	imx6q_pm_pu_power_on(&imx6q_pu_domain.base);
414 
415 	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
416 		return 0;
417 
418 	pm_genpd_init(&imx6q_pu_domain.base, NULL, false);
419 	return of_genpd_add_provider_onecell(dev->of_node,
420 					     &imx_gpc_onecell_data);
421 
422 clk_err:
423 	while (i--)
424 		clk_put(imx6q_pu_domain.clk[i]);
425 	return -EINVAL;
426 }
427 
428 static int imx_gpc_probe(struct platform_device *pdev)
429 {
430 	struct regulator *pu_reg;
431 	int ret;
432 
433 	/* bail out if DT too old and doesn't provide the necessary info */
434 	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells"))
435 		return 0;
436 
437 	pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
438 	if (PTR_ERR(pu_reg) == -ENODEV)
439 		pu_reg = NULL;
440 	if (IS_ERR(pu_reg)) {
441 		ret = PTR_ERR(pu_reg);
442 		dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret);
443 		return ret;
444 	}
445 
446 	return imx_gpc_genpd_init(&pdev->dev, pu_reg);
447 }
448 
449 static const struct of_device_id imx_gpc_dt_ids[] = {
450 	{ .compatible = "fsl,imx6q-gpc" },
451 	{ .compatible = "fsl,imx6sl-gpc" },
452 	{ }
453 };
454 
455 static struct platform_driver imx_gpc_driver = {
456 	.driver = {
457 		.name = "imx-gpc",
458 		.of_match_table = imx_gpc_dt_ids,
459 	},
460 	.probe = imx_gpc_probe,
461 };
462 
463 static int __init imx_pgc_init(void)
464 {
465 	return platform_driver_register(&imx_gpc_driver);
466 }
467 subsys_initcall(imx_pgc_init);
468