1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2016 MediaTek Inc.
4 * Author: Youlin.Pei <youlin.pei@mediatek.com>
5 */
6
7 #include <linux/interrupt.h>
8 #include <linux/io.h>
9 #include <linux/irq.h>
10 #include <linux/irqchip.h>
11 #include <linux/irqdomain.h>
12 #include <linux/of.h>
13 #include <linux/of_irq.h>
14 #include <linux/of_address.h>
15 #include <linux/slab.h>
16 #include <linux/syscore_ops.h>
17
18 enum mtk_cirq_regoffs_index {
19 CIRQ_STA,
20 CIRQ_ACK,
21 CIRQ_MASK_SET,
22 CIRQ_MASK_CLR,
23 CIRQ_SENS_SET,
24 CIRQ_SENS_CLR,
25 CIRQ_POL_SET,
26 CIRQ_POL_CLR,
27 CIRQ_CONTROL
28 };
29
30 static const u32 mtk_cirq_regoffs_v1[] = {
31 [CIRQ_STA] = 0x0,
32 [CIRQ_ACK] = 0x40,
33 [CIRQ_MASK_SET] = 0xc0,
34 [CIRQ_MASK_CLR] = 0x100,
35 [CIRQ_SENS_SET] = 0x180,
36 [CIRQ_SENS_CLR] = 0x1c0,
37 [CIRQ_POL_SET] = 0x240,
38 [CIRQ_POL_CLR] = 0x280,
39 [CIRQ_CONTROL] = 0x300,
40 };
41
42 static const u32 mtk_cirq_regoffs_v2[] = {
43 [CIRQ_STA] = 0x0,
44 [CIRQ_ACK] = 0x80,
45 [CIRQ_MASK_SET] = 0x180,
46 [CIRQ_MASK_CLR] = 0x200,
47 [CIRQ_SENS_SET] = 0x300,
48 [CIRQ_SENS_CLR] = 0x380,
49 [CIRQ_POL_SET] = 0x480,
50 [CIRQ_POL_CLR] = 0x500,
51 [CIRQ_CONTROL] = 0x600,
52 };
53
54 #define CIRQ_EN 0x1
55 #define CIRQ_EDGE 0x2
56 #define CIRQ_FLUSH 0x4
57
58 struct mtk_cirq_chip_data {
59 void __iomem *base;
60 unsigned int ext_irq_start;
61 unsigned int ext_irq_end;
62 const u32 *offsets;
63 struct irq_domain *domain;
64 };
65
66 static struct mtk_cirq_chip_data *cirq_data;
67
mtk_cirq_reg(struct mtk_cirq_chip_data * chip_data,enum mtk_cirq_regoffs_index idx)68 static void __iomem *mtk_cirq_reg(struct mtk_cirq_chip_data *chip_data,
69 enum mtk_cirq_regoffs_index idx)
70 {
71 return chip_data->base + chip_data->offsets[idx];
72 }
73
mtk_cirq_irq_reg(struct mtk_cirq_chip_data * chip_data,enum mtk_cirq_regoffs_index idx,unsigned int cirq_num)74 static void __iomem *mtk_cirq_irq_reg(struct mtk_cirq_chip_data *chip_data,
75 enum mtk_cirq_regoffs_index idx,
76 unsigned int cirq_num)
77 {
78 return mtk_cirq_reg(chip_data, idx) + (cirq_num / 32) * 4;
79 }
80
mtk_cirq_write_mask(struct irq_data * data,enum mtk_cirq_regoffs_index idx)81 static void mtk_cirq_write_mask(struct irq_data *data, enum mtk_cirq_regoffs_index idx)
82 {
83 struct mtk_cirq_chip_data *chip_data = data->chip_data;
84 unsigned int cirq_num = data->hwirq;
85 u32 mask = 1 << (cirq_num % 32);
86
87 writel_relaxed(mask, mtk_cirq_irq_reg(chip_data, idx, cirq_num));
88 }
89
mtk_cirq_mask(struct irq_data * data)90 static void mtk_cirq_mask(struct irq_data *data)
91 {
92 mtk_cirq_write_mask(data, CIRQ_MASK_SET);
93 irq_chip_mask_parent(data);
94 }
95
mtk_cirq_unmask(struct irq_data * data)96 static void mtk_cirq_unmask(struct irq_data *data)
97 {
98 mtk_cirq_write_mask(data, CIRQ_MASK_CLR);
99 irq_chip_unmask_parent(data);
100 }
101
mtk_cirq_set_type(struct irq_data * data,unsigned int type)102 static int mtk_cirq_set_type(struct irq_data *data, unsigned int type)
103 {
104 int ret;
105
106 switch (type & IRQ_TYPE_SENSE_MASK) {
107 case IRQ_TYPE_EDGE_FALLING:
108 mtk_cirq_write_mask(data, CIRQ_POL_CLR);
109 mtk_cirq_write_mask(data, CIRQ_SENS_CLR);
110 break;
111 case IRQ_TYPE_EDGE_RISING:
112 mtk_cirq_write_mask(data, CIRQ_POL_SET);
113 mtk_cirq_write_mask(data, CIRQ_SENS_CLR);
114 break;
115 case IRQ_TYPE_LEVEL_LOW:
116 mtk_cirq_write_mask(data, CIRQ_POL_CLR);
117 mtk_cirq_write_mask(data, CIRQ_SENS_SET);
118 break;
119 case IRQ_TYPE_LEVEL_HIGH:
120 mtk_cirq_write_mask(data, CIRQ_POL_SET);
121 mtk_cirq_write_mask(data, CIRQ_SENS_SET);
122 break;
123 default:
124 break;
125 }
126
127 data = data->parent_data;
128 ret = data->chip->irq_set_type(data, type);
129 return ret;
130 }
131
132 static struct irq_chip mtk_cirq_chip = {
133 .name = "MT_CIRQ",
134 .irq_mask = mtk_cirq_mask,
135 .irq_unmask = mtk_cirq_unmask,
136 .irq_eoi = irq_chip_eoi_parent,
137 .irq_set_type = mtk_cirq_set_type,
138 .irq_retrigger = irq_chip_retrigger_hierarchy,
139 #ifdef CONFIG_SMP
140 .irq_set_affinity = irq_chip_set_affinity_parent,
141 #endif
142 };
143
mtk_cirq_domain_translate(struct irq_domain * d,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)144 static int mtk_cirq_domain_translate(struct irq_domain *d,
145 struct irq_fwspec *fwspec,
146 unsigned long *hwirq,
147 unsigned int *type)
148 {
149 if (is_of_node(fwspec->fwnode)) {
150 if (fwspec->param_count != 3)
151 return -EINVAL;
152
153 /* No PPI should point to this domain */
154 if (fwspec->param[0] != 0)
155 return -EINVAL;
156
157 /* cirq support irq number check */
158 if (fwspec->param[1] < cirq_data->ext_irq_start ||
159 fwspec->param[1] > cirq_data->ext_irq_end)
160 return -EINVAL;
161
162 *hwirq = fwspec->param[1] - cirq_data->ext_irq_start;
163 *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
164 return 0;
165 }
166
167 return -EINVAL;
168 }
169
mtk_cirq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)170 static int mtk_cirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
171 unsigned int nr_irqs, void *arg)
172 {
173 int ret;
174 irq_hw_number_t hwirq;
175 unsigned int type;
176 struct irq_fwspec *fwspec = arg;
177 struct irq_fwspec parent_fwspec = *fwspec;
178
179 ret = mtk_cirq_domain_translate(domain, fwspec, &hwirq, &type);
180 if (ret)
181 return ret;
182
183 if (WARN_ON(nr_irqs != 1))
184 return -EINVAL;
185
186 irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
187 &mtk_cirq_chip,
188 domain->host_data);
189
190 parent_fwspec.fwnode = domain->parent->fwnode;
191 return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
192 &parent_fwspec);
193 }
194
195 static const struct irq_domain_ops cirq_domain_ops = {
196 .translate = mtk_cirq_domain_translate,
197 .alloc = mtk_cirq_domain_alloc,
198 .free = irq_domain_free_irqs_common,
199 };
200
201 #ifdef CONFIG_PM_SLEEP
mtk_cirq_suspend(void)202 static int mtk_cirq_suspend(void)
203 {
204 void __iomem *reg;
205 u32 value, mask;
206 unsigned int irq, hwirq_num;
207 bool pending, masked;
208 int i, pendret, maskret;
209
210 /*
211 * When external interrupts happened, CIRQ will record the status
212 * even CIRQ is not enabled. When execute flush command, CIRQ will
213 * resend the signals according to the status. So if don't clear the
214 * status, CIRQ will resend the wrong signals.
215 *
216 * arch_suspend_disable_irqs() will be called before CIRQ suspend
217 * callback. If clear all the status simply, the external interrupts
218 * which happened between arch_suspend_disable_irqs and CIRQ suspend
219 * callback will be lost. Using following steps to avoid this issue;
220 *
221 * - Iterate over all the CIRQ supported interrupts;
222 * - For each interrupt, inspect its pending and masked status at GIC
223 * level;
224 * - If pending and unmasked, it happened between
225 * arch_suspend_disable_irqs and CIRQ suspend callback, don't ACK
226 * it. Otherwise, ACK it.
227 */
228 hwirq_num = cirq_data->ext_irq_end - cirq_data->ext_irq_start + 1;
229 for (i = 0; i < hwirq_num; i++) {
230 irq = irq_find_mapping(cirq_data->domain, i);
231 if (irq) {
232 pendret = irq_get_irqchip_state(irq,
233 IRQCHIP_STATE_PENDING,
234 &pending);
235
236 maskret = irq_get_irqchip_state(irq,
237 IRQCHIP_STATE_MASKED,
238 &masked);
239
240 if (pendret == 0 && maskret == 0 &&
241 (pending && !masked))
242 continue;
243 }
244
245 reg = mtk_cirq_irq_reg(cirq_data, CIRQ_ACK, i);
246 mask = 1 << (i % 32);
247 writel_relaxed(mask, reg);
248 }
249
250 /* set edge_only mode, record edge-triggerd interrupts */
251 /* enable cirq */
252 reg = mtk_cirq_reg(cirq_data, CIRQ_CONTROL);
253 value = readl_relaxed(reg);
254 value |= (CIRQ_EDGE | CIRQ_EN);
255 writel_relaxed(value, reg);
256
257 return 0;
258 }
259
mtk_cirq_resume(void)260 static void mtk_cirq_resume(void)
261 {
262 void __iomem *reg = mtk_cirq_reg(cirq_data, CIRQ_CONTROL);
263 u32 value;
264
265 /* flush recorded interrupts, will send signals to parent controller */
266 value = readl_relaxed(reg);
267 writel_relaxed(value | CIRQ_FLUSH, reg);
268
269 /* disable cirq */
270 value = readl_relaxed(reg);
271 value &= ~(CIRQ_EDGE | CIRQ_EN);
272 writel_relaxed(value, reg);
273 }
274
275 static struct syscore_ops mtk_cirq_syscore_ops = {
276 .suspend = mtk_cirq_suspend,
277 .resume = mtk_cirq_resume,
278 };
279
mtk_cirq_syscore_init(void)280 static void mtk_cirq_syscore_init(void)
281 {
282 register_syscore_ops(&mtk_cirq_syscore_ops);
283 }
284 #else
mtk_cirq_syscore_init(void)285 static inline void mtk_cirq_syscore_init(void) {}
286 #endif
287
288 static const struct of_device_id mtk_cirq_of_match[] = {
289 { .compatible = "mediatek,mt2701-cirq", .data = &mtk_cirq_regoffs_v1 },
290 { .compatible = "mediatek,mt8135-cirq", .data = &mtk_cirq_regoffs_v1 },
291 { .compatible = "mediatek,mt8173-cirq", .data = &mtk_cirq_regoffs_v1 },
292 { .compatible = "mediatek,mt8192-cirq", .data = &mtk_cirq_regoffs_v2 },
293 { /* sentinel */ }
294 };
295
mtk_cirq_of_init(struct device_node * node,struct device_node * parent)296 static int __init mtk_cirq_of_init(struct device_node *node,
297 struct device_node *parent)
298 {
299 struct irq_domain *domain, *domain_parent;
300 const struct of_device_id *match;
301 unsigned int irq_num;
302 int ret;
303
304 domain_parent = irq_find_host(parent);
305 if (!domain_parent) {
306 pr_err("mtk_cirq: interrupt-parent not found\n");
307 return -EINVAL;
308 }
309
310 cirq_data = kzalloc(sizeof(*cirq_data), GFP_KERNEL);
311 if (!cirq_data)
312 return -ENOMEM;
313
314 cirq_data->base = of_iomap(node, 0);
315 if (!cirq_data->base) {
316 pr_err("mtk_cirq: unable to map cirq register\n");
317 ret = -ENXIO;
318 goto out_free;
319 }
320
321 ret = of_property_read_u32_index(node, "mediatek,ext-irq-range", 0,
322 &cirq_data->ext_irq_start);
323 if (ret)
324 goto out_unmap;
325
326 ret = of_property_read_u32_index(node, "mediatek,ext-irq-range", 1,
327 &cirq_data->ext_irq_end);
328 if (ret)
329 goto out_unmap;
330
331 match = of_match_node(mtk_cirq_of_match, node);
332 if (!match) {
333 ret = -ENODEV;
334 goto out_unmap;
335 }
336 cirq_data->offsets = match->data;
337
338 irq_num = cirq_data->ext_irq_end - cirq_data->ext_irq_start + 1;
339 domain = irq_domain_add_hierarchy(domain_parent, 0,
340 irq_num, node,
341 &cirq_domain_ops, cirq_data);
342 if (!domain) {
343 ret = -ENOMEM;
344 goto out_unmap;
345 }
346 cirq_data->domain = domain;
347
348 mtk_cirq_syscore_init();
349
350 return 0;
351
352 out_unmap:
353 iounmap(cirq_data->base);
354 out_free:
355 kfree(cirq_data);
356 return ret;
357 }
358
359 IRQCHIP_DECLARE(mtk_cirq, "mediatek,mtk-cirq", mtk_cirq_of_init);
360