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
47struct 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
54static void __iomem *gpc_base;
55static u32 gpc_wake_irqs[IMR_NUM];
56static u32 gpc_saved_imrs[IMR_NUM];
57
58void 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
64void 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
70void imx_gpc_set_arm_power_in_lpm(bool power_off)
71{
72	writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
73}
74
75void 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
90void 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
102static 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
118void 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
130void 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
139void 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
150void 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
161static 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
167static 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
173static 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
186static 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
207static 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
235static 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
241static 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	return 0;
275}
276IRQCHIP_DECLARE(imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
277
278void __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		return;
285
286	if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
287		pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
288
289		/* map GPC, so that at least CPUidle and WARs keep working */
290		gpc_base = of_iomap(np, 0);
291	}
292}
293
294static void _imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
295{
296	int iso, iso2sw;
297	u32 val;
298
299	/* Read ISO and ISO2SW power down delays */
300	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PDNSCR);
301	iso = val & 0x3f;
302	iso2sw = (val >> 8) & 0x3f;
303
304	/* Gate off PU domain when GPU/VPU when powered down */
305	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
306
307	/* Request GPC to power down GPU/VPU */
308	val = readl_relaxed(gpc_base + GPC_CNTR);
309	val |= GPU_VPU_PDN_REQ;
310	writel_relaxed(val, gpc_base + GPC_CNTR);
311
312	/* Wait ISO + ISO2SW IPG clock cycles */
313	ndelay((iso + iso2sw) * 1000 / 66);
314}
315
316static int imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
317{
318	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
319
320	_imx6q_pm_pu_power_off(genpd);
321
322	if (pu->reg)
323		regulator_disable(pu->reg);
324
325	return 0;
326}
327
328static int imx6q_pm_pu_power_on(struct generic_pm_domain *genpd)
329{
330	struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
331	int i, ret, sw, sw2iso;
332	u32 val;
333
334	if (pu->reg)
335		ret = regulator_enable(pu->reg);
336	if (pu->reg && ret) {
337		pr_err("%s: failed to enable regulator: %d\n", __func__, ret);
338		return ret;
339	}
340
341	/* Enable reset clocks for all devices in the PU domain */
342	for (i = 0; i < pu->num_clks; i++)
343		clk_prepare_enable(pu->clk[i]);
344
345	/* Gate off PU domain when GPU/VPU when powered down */
346	writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
347
348	/* Read ISO and ISO2SW power down delays */
349	val = readl_relaxed(gpc_base + GPC_PGC_GPU_PUPSCR);
350	sw = val & 0x3f;
351	sw2iso = (val >> 8) & 0x3f;
352
353	/* Request GPC to power up GPU/VPU */
354	val = readl_relaxed(gpc_base + GPC_CNTR);
355	val |= GPU_VPU_PUP_REQ;
356	writel_relaxed(val, gpc_base + GPC_CNTR);
357
358	/* Wait ISO + ISO2SW IPG clock cycles */
359	ndelay((sw + sw2iso) * 1000 / 66);
360
361	/* Disable reset clocks for all devices in the PU domain */
362	for (i = 0; i < pu->num_clks; i++)
363		clk_disable_unprepare(pu->clk[i]);
364
365	return 0;
366}
367
368static struct generic_pm_domain imx6q_arm_domain = {
369	.name = "ARM",
370};
371
372static struct pu_domain imx6q_pu_domain = {
373	.base = {
374		.name = "PU",
375		.power_off = imx6q_pm_pu_power_off,
376		.power_on = imx6q_pm_pu_power_on,
377		.power_off_latency_ns = 25000,
378		.power_on_latency_ns = 2000000,
379	},
380};
381
382static struct generic_pm_domain imx6sl_display_domain = {
383	.name = "DISPLAY",
384};
385
386static struct generic_pm_domain *imx_gpc_domains[] = {
387	&imx6q_arm_domain,
388	&imx6q_pu_domain.base,
389	&imx6sl_display_domain,
390};
391
392static struct genpd_onecell_data imx_gpc_onecell_data = {
393	.domains = imx_gpc_domains,
394	.num_domains = ARRAY_SIZE(imx_gpc_domains),
395};
396
397static int imx_gpc_genpd_init(struct device *dev, struct regulator *pu_reg)
398{
399	struct clk *clk;
400	int i;
401
402	imx6q_pu_domain.reg = pu_reg;
403
404	for (i = 0; ; i++) {
405		clk = of_clk_get(dev->of_node, i);
406		if (IS_ERR(clk))
407			break;
408		if (i >= GPC_CLK_MAX) {
409			dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
410			goto clk_err;
411		}
412		imx6q_pu_domain.clk[i] = clk;
413	}
414	imx6q_pu_domain.num_clks = i;
415
416	/* Enable power always in case bootloader disabled it. */
417	imx6q_pm_pu_power_on(&imx6q_pu_domain.base);
418
419	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
420		return 0;
421
422	pm_genpd_init(&imx6q_pu_domain.base, NULL, false);
423	return of_genpd_add_provider_onecell(dev->of_node,
424					     &imx_gpc_onecell_data);
425
426clk_err:
427	while (i--)
428		clk_put(imx6q_pu_domain.clk[i]);
429	return -EINVAL;
430}
431
432static int imx_gpc_probe(struct platform_device *pdev)
433{
434	struct regulator *pu_reg;
435	int ret;
436
437	/* bail out if DT too old and doesn't provide the necessary info */
438	if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells"))
439		return 0;
440
441	pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
442	if (PTR_ERR(pu_reg) == -ENODEV)
443		pu_reg = NULL;
444	if (IS_ERR(pu_reg)) {
445		ret = PTR_ERR(pu_reg);
446		dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret);
447		return ret;
448	}
449
450	return imx_gpc_genpd_init(&pdev->dev, pu_reg);
451}
452
453static const struct of_device_id imx_gpc_dt_ids[] = {
454	{ .compatible = "fsl,imx6q-gpc" },
455	{ .compatible = "fsl,imx6sl-gpc" },
456	{ }
457};
458
459static struct platform_driver imx_gpc_driver = {
460	.driver = {
461		.name = "imx-gpc",
462		.of_match_table = imx_gpc_dt_ids,
463	},
464	.probe = imx_gpc_probe,
465};
466
467static int __init imx_pgc_init(void)
468{
469	return platform_driver_register(&imx_gpc_driver);
470}
471subsys_initcall(imx_pgc_init);
472