xref: /linux/drivers/gpu/drm/imx/dc/dc-ic.c (revision 570f7e331f5febb30f1384817463c7e42b65ca7d)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2024 NXP
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/interrupt.h>
8 #include <linux/irq.h>
9 #include <linux/irqchip/chained_irq.h>
10 #include <linux/irqdomain.h>
11 #include <linux/of.h>
12 #include <linux/of_irq.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/regmap.h>
16 
17 #include "dc-drv.h"
18 
19 #define USERINTERRUPTMASK(n)	(0x8 + 4 * (n))
20 #define INTERRUPTENABLE(n)	(0x10 + 4 * (n))
21 #define INTERRUPTPRESET(n)	(0x18 + 4 * (n))
22 #define INTERRUPTCLEAR(n)	(0x20 + 4 * (n))
23 #define INTERRUPTSTATUS(n)	(0x28 + 4 * (n))
24 #define USERINTERRUPTENABLE(n)	(0x40 + 4 * (n))
25 #define USERINTERRUPTPRESET(n)	(0x48 + 4 * (n))
26 #define USERINTERRUPTCLEAR(n)	(0x50 + 4 * (n))
27 #define USERINTERRUPTSTATUS(n)	(0x58 + 4 * (n))
28 
29 #define IRQ_COUNT	49
30 #define IRQ_RESERVED	35
31 #define REG_NUM		2
32 
33 struct dc_ic_data {
34 	struct regmap		*regs;
35 	struct clk		*clk_axi;
36 	int			irq[IRQ_COUNT];
37 	struct irq_domain	*domain;
38 };
39 
40 struct dc_ic_entry {
41 	struct dc_ic_data *data;
42 	int irq;
43 };
44 
45 static const struct regmap_range dc_ic_regmap_write_ranges[] = {
46 	regmap_reg_range(USERINTERRUPTMASK(0), INTERRUPTCLEAR(1)),
47 	regmap_reg_range(USERINTERRUPTENABLE(0), USERINTERRUPTCLEAR(1)),
48 };
49 
50 static const struct regmap_access_table dc_ic_regmap_write_table = {
51 	.yes_ranges = dc_ic_regmap_write_ranges,
52 	.n_yes_ranges = ARRAY_SIZE(dc_ic_regmap_write_ranges),
53 };
54 
55 static const struct regmap_range dc_ic_regmap_read_ranges[] = {
56 	regmap_reg_range(USERINTERRUPTMASK(0), INTERRUPTENABLE(1)),
57 	regmap_reg_range(INTERRUPTSTATUS(0), INTERRUPTSTATUS(1)),
58 	regmap_reg_range(USERINTERRUPTENABLE(0), USERINTERRUPTENABLE(1)),
59 	regmap_reg_range(USERINTERRUPTSTATUS(0), USERINTERRUPTSTATUS(1)),
60 };
61 
62 static const struct regmap_access_table dc_ic_regmap_read_table = {
63 	.yes_ranges = dc_ic_regmap_read_ranges,
64 	.n_yes_ranges = ARRAY_SIZE(dc_ic_regmap_read_ranges),
65 };
66 
67 static const struct regmap_range dc_ic_regmap_volatile_ranges[] = {
68 	regmap_reg_range(INTERRUPTPRESET(0), INTERRUPTCLEAR(1)),
69 	regmap_reg_range(USERINTERRUPTPRESET(0), USERINTERRUPTCLEAR(1)),
70 };
71 
72 static const struct regmap_access_table dc_ic_regmap_volatile_table = {
73 	.yes_ranges = dc_ic_regmap_volatile_ranges,
74 	.n_yes_ranges = ARRAY_SIZE(dc_ic_regmap_volatile_ranges),
75 };
76 
77 static const struct regmap_config dc_ic_regmap_config = {
78 	.reg_bits = 32,
79 	.reg_stride = 4,
80 	.val_bits = 32,
81 	.fast_io = true,
82 	.wr_table = &dc_ic_regmap_write_table,
83 	.rd_table = &dc_ic_regmap_read_table,
84 	.volatile_table = &dc_ic_regmap_volatile_table,
85 	.max_register = USERINTERRUPTSTATUS(1),
86 };
87 
88 static void dc_ic_irq_handler(struct irq_desc *desc)
89 {
90 	struct dc_ic_entry *entry = irq_desc_get_handler_data(desc);
91 	struct dc_ic_data *data = entry->data;
92 	unsigned int status, enable;
93 	unsigned int virq;
94 
95 	chained_irq_enter(irq_desc_get_chip(desc), desc);
96 
97 	regmap_read(data->regs, USERINTERRUPTSTATUS(entry->irq / 32), &status);
98 	regmap_read(data->regs, USERINTERRUPTENABLE(entry->irq / 32), &enable);
99 
100 	status &= enable;
101 
102 	if (status & BIT(entry->irq % 32)) {
103 		virq = irq_find_mapping(data->domain, entry->irq);
104 		if (virq)
105 			generic_handle_irq(virq);
106 	}
107 
108 	chained_irq_exit(irq_desc_get_chip(desc), desc);
109 }
110 
111 static const unsigned long unused_irq[REG_NUM] = {0x00000000, 0xfffe0008};
112 
113 static int dc_ic_probe(struct platform_device *pdev)
114 {
115 	struct device *dev = &pdev->dev;
116 	struct irq_chip_generic *gc;
117 	struct dc_ic_entry *entry;
118 	struct irq_chip_type *ct;
119 	struct dc_ic_data *data;
120 	void __iomem *base;
121 	int i, ret;
122 
123 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
124 	if (!data)
125 		return -ENOMEM;
126 
127 	entry = devm_kcalloc(dev, IRQ_COUNT, sizeof(*entry), GFP_KERNEL);
128 	if (!entry)
129 		return -ENOMEM;
130 
131 	base = devm_platform_ioremap_resource(pdev, 0);
132 	if (IS_ERR(base)) {
133 		dev_err(dev, "failed to initialize reg\n");
134 		return PTR_ERR(base);
135 	}
136 
137 	data->regs = devm_regmap_init_mmio(dev, base, &dc_ic_regmap_config);
138 	if (IS_ERR(data->regs))
139 		return PTR_ERR(data->regs);
140 
141 	data->clk_axi = devm_clk_get(dev, NULL);
142 	if (IS_ERR(data->clk_axi))
143 		return dev_err_probe(dev, PTR_ERR(data->clk_axi),
144 				     "failed to get AXI clock\n");
145 
146 	for (i = 0; i < IRQ_COUNT; i++) {
147 		/* skip the reserved IRQ */
148 		if (i == IRQ_RESERVED)
149 			continue;
150 
151 		ret = platform_get_irq(pdev, i);
152 		if (ret < 0)
153 			return ret;
154 	}
155 
156 	dev_set_drvdata(dev, data);
157 
158 	ret = devm_pm_runtime_enable(dev);
159 	if (ret)
160 		return ret;
161 
162 	ret = pm_runtime_resume_and_get(dev);
163 	if (ret < 0) {
164 		dev_err(dev, "failed to get runtime PM sync: %d\n", ret);
165 		return ret;
166 	}
167 
168 	for (i = 0; i < REG_NUM; i++) {
169 		/* mask and clear all interrupts */
170 		regmap_write(data->regs, USERINTERRUPTENABLE(i), 0x0);
171 		regmap_write(data->regs, INTERRUPTENABLE(i), 0x0);
172 		regmap_write(data->regs, USERINTERRUPTCLEAR(i), 0xffffffff);
173 		regmap_write(data->regs, INTERRUPTCLEAR(i), 0xffffffff);
174 
175 		/* set all interrupts to user mode */
176 		regmap_write(data->regs, USERINTERRUPTMASK(i), 0xffffffff);
177 	}
178 
179 	data->domain = irq_domain_create_linear(of_fwnode_handle(dev->of_node), IRQ_COUNT,
180 						&irq_generic_chip_ops, data);
181 	if (!data->domain) {
182 		dev_err(dev, "failed to create IRQ domain\n");
183 		pm_runtime_put(dev);
184 		return -ENOMEM;
185 	}
186 	irq_domain_set_pm_device(data->domain, dev);
187 
188 	ret = irq_alloc_domain_generic_chips(data->domain, 32, 1, "DC",
189 					     handle_level_irq, 0, 0, 0);
190 	if (ret) {
191 		dev_err(dev, "failed to alloc generic IRQ chips: %d\n", ret);
192 		irq_domain_remove(data->domain);
193 		pm_runtime_put(dev);
194 		return ret;
195 	}
196 
197 	for (i = 0; i < IRQ_COUNT; i += 32) {
198 		gc = irq_get_domain_generic_chip(data->domain, i);
199 		gc->reg_base = base;
200 		gc->unused = unused_irq[i / 32];
201 		ct = gc->chip_types;
202 		ct->chip.irq_ack = irq_gc_ack_set_bit;
203 		ct->chip.irq_mask = irq_gc_mask_clr_bit;
204 		ct->chip.irq_unmask = irq_gc_mask_set_bit;
205 		ct->regs.ack = USERINTERRUPTCLEAR(i / 32);
206 		ct->regs.mask = USERINTERRUPTENABLE(i / 32);
207 	}
208 
209 	for (i = 0; i < IRQ_COUNT; i++) {
210 		/* skip the reserved IRQ */
211 		if (i == IRQ_RESERVED)
212 			continue;
213 
214 		data->irq[i] = irq_of_parse_and_map(dev->of_node, i);
215 
216 		entry[i].data = data;
217 		entry[i].irq = i;
218 
219 		irq_set_chained_handler_and_data(data->irq[i],
220 						 dc_ic_irq_handler, &entry[i]);
221 	}
222 
223 	return 0;
224 }
225 
226 static void dc_ic_remove(struct platform_device *pdev)
227 {
228 	struct dc_ic_data *data = dev_get_drvdata(&pdev->dev);
229 	int i;
230 
231 	for (i = 0; i < IRQ_COUNT; i++) {
232 		if (i == IRQ_RESERVED)
233 			continue;
234 
235 		irq_set_chained_handler_and_data(data->irq[i], NULL, NULL);
236 	}
237 
238 	irq_domain_remove(data->domain);
239 
240 	pm_runtime_put_sync(&pdev->dev);
241 }
242 
243 static int dc_ic_runtime_suspend(struct device *dev)
244 {
245 	struct dc_ic_data *data = dev_get_drvdata(dev);
246 
247 	clk_disable_unprepare(data->clk_axi);
248 
249 	return 0;
250 }
251 
252 static int dc_ic_runtime_resume(struct device *dev)
253 {
254 	struct dc_ic_data *data = dev_get_drvdata(dev);
255 	int ret;
256 
257 	ret = clk_prepare_enable(data->clk_axi);
258 	if (ret)
259 		dev_err(dev, "failed to enable AXI clock: %d\n", ret);
260 
261 	return ret;
262 }
263 
264 static const struct dev_pm_ops dc_ic_pm_ops = {
265 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
266 				      pm_runtime_force_resume)
267 	RUNTIME_PM_OPS(dc_ic_runtime_suspend, dc_ic_runtime_resume, NULL)
268 };
269 
270 static const struct of_device_id dc_ic_dt_ids[] = {
271 	{ .compatible = "fsl,imx8qxp-dc-intc", },
272 	{ /* sentinel */ }
273 };
274 
275 struct platform_driver dc_ic_driver = {
276 	.probe = dc_ic_probe,
277 	.remove = dc_ic_remove,
278 	.driver = {
279 		.name = "imx8-dc-intc",
280 		.suppress_bind_attrs = true,
281 		.of_match_table	= dc_ic_dt_ids,
282 		.pm = pm_sleep_ptr(&dc_ic_pm_ops),
283 	},
284 };
285