1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Broadcom BCM7120 style Level 2 interrupt controller driver
4 *
5 * Copyright (C) 2014 Broadcom Corporation
6 */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/init.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/platform_device.h>
15 #include <linux/of.h>
16 #include <linux/of_irq.h>
17 #include <linux/of_address.h>
18 #include <linux/of_platform.h>
19 #include <linux/interrupt.h>
20 #include <linux/irq.h>
21 #include <linux/io.h>
22 #include <linux/irqdomain.h>
23 #include <linux/reboot.h>
24 #include <linux/bitops.h>
25 #include <linux/irqchip.h>
26 #include <linux/irqchip/chained_irq.h>
27
28 /* Register offset in the L2 interrupt controller */
29 #define IRQEN 0x00
30 #define IRQSTAT 0x04
31
32 #define MAX_WORDS 4
33 #define MAX_MAPPINGS (MAX_WORDS * 2)
34 #define IRQS_PER_WORD 32
35
36 struct bcm7120_l1_intc_data {
37 struct bcm7120_l2_intc_data *b;
38 u32 irq_map_mask[MAX_WORDS];
39 };
40
41 struct bcm7120_l2_intc_data {
42 unsigned int n_words;
43 void __iomem *map_base[MAX_MAPPINGS];
44 void __iomem *pair_base[MAX_WORDS];
45 int en_offset[MAX_WORDS];
46 int stat_offset[MAX_WORDS];
47 struct irq_domain *domain;
48 bool can_wake;
49 u32 irq_fwd_mask[MAX_WORDS];
50 struct bcm7120_l1_intc_data *l1_data;
51 int num_parent_irqs;
52 const __be32 *map_mask_prop;
53 };
54
bcm7120_l2_intc_irq_handle(struct irq_desc * desc)55 static void bcm7120_l2_intc_irq_handle(struct irq_desc *desc)
56 {
57 struct bcm7120_l1_intc_data *data = irq_desc_get_handler_data(desc);
58 struct bcm7120_l2_intc_data *b = data->b;
59 struct irq_chip *chip = irq_desc_get_chip(desc);
60 unsigned int idx;
61
62 chained_irq_enter(chip, desc);
63
64 for (idx = 0; idx < b->n_words; idx++) {
65 int base = idx * IRQS_PER_WORD;
66 struct irq_chip_generic *gc =
67 irq_get_domain_generic_chip(b->domain, base);
68 unsigned long pending;
69 int hwirq;
70
71 irq_gc_lock(gc);
72 pending = irq_reg_readl(gc, b->stat_offset[idx]) &
73 gc->mask_cache &
74 data->irq_map_mask[idx];
75 irq_gc_unlock(gc);
76
77 for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
78 generic_handle_irq(irq_find_mapping(b->domain,
79 base + hwirq));
80 }
81 }
82
83 chained_irq_exit(chip, desc);
84 }
85
bcm7120_l2_intc_suspend(struct irq_chip_generic * gc)86 static void bcm7120_l2_intc_suspend(struct irq_chip_generic *gc)
87 {
88 struct bcm7120_l2_intc_data *b = gc->private;
89 struct irq_chip_type *ct = gc->chip_types;
90
91 irq_gc_lock(gc);
92 if (b->can_wake)
93 irq_reg_writel(gc, gc->mask_cache | gc->wake_active,
94 ct->regs.mask);
95 irq_gc_unlock(gc);
96 }
97
bcm7120_l2_intc_resume(struct irq_chip_generic * gc)98 static void bcm7120_l2_intc_resume(struct irq_chip_generic *gc)
99 {
100 struct irq_chip_type *ct = gc->chip_types;
101
102 /* Restore the saved mask */
103 irq_gc_lock(gc);
104 irq_reg_writel(gc, gc->mask_cache, ct->regs.mask);
105 irq_gc_unlock(gc);
106 }
107
bcm7120_l2_intc_init_one(struct device_node * dn,struct bcm7120_l2_intc_data * data,int irq,u32 * valid_mask)108 static int bcm7120_l2_intc_init_one(struct device_node *dn,
109 struct bcm7120_l2_intc_data *data,
110 int irq, u32 *valid_mask)
111 {
112 struct bcm7120_l1_intc_data *l1_data = &data->l1_data[irq];
113 int parent_irq;
114 unsigned int idx;
115
116 parent_irq = irq_of_parse_and_map(dn, irq);
117 if (!parent_irq) {
118 pr_err("failed to map interrupt %d\n", irq);
119 return -EINVAL;
120 }
121
122 /* For multiple parent IRQs with multiple words, this looks like:
123 * <irq0_w0 irq0_w1 irq1_w0 irq1_w1 ...>
124 *
125 * We need to associate a given parent interrupt with its corresponding
126 * map_mask in order to mask the status register with it because we
127 * have the same handler being called for multiple parent interrupts.
128 *
129 * This is typically something needed on BCM7xxx (STB chips).
130 */
131 for (idx = 0; idx < data->n_words; idx++) {
132 if (data->map_mask_prop) {
133 l1_data->irq_map_mask[idx] |=
134 be32_to_cpup(data->map_mask_prop +
135 irq * data->n_words + idx);
136 } else {
137 l1_data->irq_map_mask[idx] = 0xffffffff;
138 }
139 valid_mask[idx] |= l1_data->irq_map_mask[idx];
140 }
141
142 l1_data->b = data;
143
144 irq_set_chained_handler_and_data(parent_irq,
145 bcm7120_l2_intc_irq_handle, l1_data);
146 if (data->can_wake)
147 enable_irq_wake(parent_irq);
148
149 return 0;
150 }
151
bcm7120_l2_intc_iomap_7120(struct device_node * dn,struct bcm7120_l2_intc_data * data)152 static int __init bcm7120_l2_intc_iomap_7120(struct device_node *dn,
153 struct bcm7120_l2_intc_data *data)
154 {
155 int ret;
156
157 data->map_base[0] = of_iomap(dn, 0);
158 if (!data->map_base[0]) {
159 pr_err("unable to map registers\n");
160 return -ENOMEM;
161 }
162
163 data->pair_base[0] = data->map_base[0];
164 data->en_offset[0] = IRQEN;
165 data->stat_offset[0] = IRQSTAT;
166 data->n_words = 1;
167
168 ret = of_property_read_u32_array(dn, "brcm,int-fwd-mask",
169 data->irq_fwd_mask, data->n_words);
170 if (ret != 0 && ret != -EINVAL) {
171 /* property exists but has the wrong number of words */
172 pr_err("invalid brcm,int-fwd-mask property\n");
173 return -EINVAL;
174 }
175
176 data->map_mask_prop = of_get_property(dn, "brcm,int-map-mask", &ret);
177 if (!data->map_mask_prop ||
178 (ret != (sizeof(__be32) * data->num_parent_irqs * data->n_words))) {
179 pr_err("invalid brcm,int-map-mask property\n");
180 return -EINVAL;
181 }
182
183 return 0;
184 }
185
bcm7120_l2_intc_iomap_3380(struct device_node * dn,struct bcm7120_l2_intc_data * data)186 static int __init bcm7120_l2_intc_iomap_3380(struct device_node *dn,
187 struct bcm7120_l2_intc_data *data)
188 {
189 unsigned int gc_idx;
190
191 for (gc_idx = 0; gc_idx < MAX_WORDS; gc_idx++) {
192 unsigned int map_idx = gc_idx * 2;
193 void __iomem *en = of_iomap(dn, map_idx + 0);
194 void __iomem *stat = of_iomap(dn, map_idx + 1);
195 void __iomem *base = min(en, stat);
196
197 data->map_base[map_idx + 0] = en;
198 data->map_base[map_idx + 1] = stat;
199
200 if (!base)
201 break;
202
203 data->pair_base[gc_idx] = base;
204 data->en_offset[gc_idx] = en - base;
205 data->stat_offset[gc_idx] = stat - base;
206 }
207
208 if (!gc_idx) {
209 pr_err("unable to map registers\n");
210 return -EINVAL;
211 }
212
213 data->n_words = gc_idx;
214 return 0;
215 }
216
bcm7120_l2_intc_probe(struct device_node * dn,struct device_node * parent,int (* iomap_regs_fn)(struct device_node *,struct bcm7120_l2_intc_data *),const char * intc_name)217 static int __init bcm7120_l2_intc_probe(struct device_node *dn,
218 struct device_node *parent,
219 int (*iomap_regs_fn)(struct device_node *,
220 struct bcm7120_l2_intc_data *),
221 const char *intc_name)
222 {
223 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
224 struct bcm7120_l2_intc_data *data;
225 struct irq_chip_generic *gc;
226 struct irq_chip_type *ct;
227 int ret = 0;
228 unsigned int idx, irq, flags;
229 u32 valid_mask[MAX_WORDS] = { };
230
231 data = kzalloc(sizeof(*data), GFP_KERNEL);
232 if (!data)
233 return -ENOMEM;
234
235 data->num_parent_irqs = of_irq_count(dn);
236 if (data->num_parent_irqs <= 0) {
237 pr_err("invalid number of parent interrupts\n");
238 ret = -ENOMEM;
239 goto out_unmap;
240 }
241
242 data->l1_data = kcalloc(data->num_parent_irqs, sizeof(*data->l1_data),
243 GFP_KERNEL);
244 if (!data->l1_data) {
245 ret = -ENOMEM;
246 goto out_free_l1_data;
247 }
248
249 ret = iomap_regs_fn(dn, data);
250 if (ret < 0)
251 goto out_free_l1_data;
252
253 data->can_wake = of_property_read_bool(dn, "brcm,irq-can-wake");
254
255 for (irq = 0; irq < data->num_parent_irqs; irq++) {
256 ret = bcm7120_l2_intc_init_one(dn, data, irq, valid_mask);
257 if (ret)
258 goto out_free_l1_data;
259 }
260
261 data->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * data->n_words,
262 &irq_generic_chip_ops, NULL);
263 if (!data->domain) {
264 ret = -ENOMEM;
265 goto out_free_l1_data;
266 }
267
268 /* MIPS chips strapped for BE will automagically configure the
269 * peripheral registers for CPU-native byte order.
270 */
271 flags = IRQ_GC_INIT_MASK_CACHE;
272 if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
273 flags |= IRQ_GC_BE_IO;
274
275 ret = irq_alloc_domain_generic_chips(data->domain, IRQS_PER_WORD, 1,
276 dn->full_name, handle_level_irq, clr, 0, flags);
277 if (ret) {
278 pr_err("failed to allocate generic irq chip\n");
279 goto out_free_domain;
280 }
281
282 for (idx = 0; idx < data->n_words; idx++) {
283 irq = idx * IRQS_PER_WORD;
284 gc = irq_get_domain_generic_chip(data->domain, irq);
285
286 gc->unused = 0xffffffff & ~valid_mask[idx];
287 gc->private = data;
288 ct = gc->chip_types;
289
290 gc->reg_base = data->pair_base[idx];
291 ct->regs.mask = data->en_offset[idx];
292
293 /* gc->reg_base is defined and so is gc->writel */
294 irq_reg_writel(gc, data->irq_fwd_mask[idx],
295 data->en_offset[idx]);
296
297 ct->chip.irq_mask = irq_gc_mask_clr_bit;
298 ct->chip.irq_unmask = irq_gc_mask_set_bit;
299 ct->chip.irq_ack = irq_gc_noop;
300 gc->suspend = bcm7120_l2_intc_suspend;
301 gc->resume = bcm7120_l2_intc_resume;
302
303 /*
304 * Initialize mask-cache, in case we need it for
305 * saving/restoring fwd mask even w/o any child interrupts
306 * installed
307 */
308 gc->mask_cache = irq_reg_readl(gc, ct->regs.mask);
309
310 if (data->can_wake) {
311 /* This IRQ chip can wake the system, set all
312 * relevant child interrupts in wake_enabled mask
313 */
314 gc->wake_enabled = 0xffffffff;
315 gc->wake_enabled &= ~gc->unused;
316 ct->chip.irq_set_wake = irq_gc_set_wake;
317 }
318 }
319
320 pr_info("registered %s intc (%pOF, parent IRQ(s): %d)\n",
321 intc_name, dn, data->num_parent_irqs);
322
323 return 0;
324
325 out_free_domain:
326 irq_domain_remove(data->domain);
327 out_free_l1_data:
328 kfree(data->l1_data);
329 out_unmap:
330 for (idx = 0; idx < MAX_MAPPINGS; idx++) {
331 if (data->map_base[idx])
332 iounmap(data->map_base[idx]);
333 }
334 kfree(data);
335 return ret;
336 }
337
bcm7120_l2_intc_probe_7120(struct device_node * dn,struct device_node * parent)338 static int __init bcm7120_l2_intc_probe_7120(struct device_node *dn,
339 struct device_node *parent)
340 {
341 return bcm7120_l2_intc_probe(dn, parent, bcm7120_l2_intc_iomap_7120,
342 "BCM7120 L2");
343 }
344
bcm7120_l2_intc_probe_3380(struct device_node * dn,struct device_node * parent)345 static int __init bcm7120_l2_intc_probe_3380(struct device_node *dn,
346 struct device_node *parent)
347 {
348 return bcm7120_l2_intc_probe(dn, parent, bcm7120_l2_intc_iomap_3380,
349 "BCM3380 L2");
350 }
351
352 IRQCHIP_DECLARE(bcm7120_l2_intc, "brcm,bcm7120-l2-intc",
353 bcm7120_l2_intc_probe_7120);
354
355 IRQCHIP_DECLARE(bcm3380_l2_intc, "brcm,bcm3380-l2-intc",
356 bcm7120_l2_intc_probe_3380);
357