1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * IMG PowerDown Controller (PDC)
4 *
5 * Copyright 2010-2013 Imagination Technologies Ltd.
6 *
7 * Exposes the syswake and PDC peripheral wake interrupts to the system.
8 *
9 */
10
11 #include <linux/bitops.h>
12 #include <linux/interrupt.h>
13 #include <linux/irqdomain.h>
14 #include <linux/io.h>
15 #include <linux/kernel.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/spinlock.h>
19
20 /* PDC interrupt register numbers */
21
22 #define PDC_IRQ_STATUS 0x310
23 #define PDC_IRQ_ENABLE 0x314
24 #define PDC_IRQ_CLEAR 0x318
25 #define PDC_IRQ_ROUTE 0x31c
26 #define PDC_SYS_WAKE_BASE 0x330
27 #define PDC_SYS_WAKE_STRIDE 0x8
28 #define PDC_SYS_WAKE_CONFIG_BASE 0x334
29 #define PDC_SYS_WAKE_CONFIG_STRIDE 0x8
30
31 /* PDC interrupt register field masks */
32
33 #define PDC_IRQ_SYS3 0x08
34 #define PDC_IRQ_SYS2 0x04
35 #define PDC_IRQ_SYS1 0x02
36 #define PDC_IRQ_SYS0 0x01
37 #define PDC_IRQ_ROUTE_WU_EN_SYS3 0x08000000
38 #define PDC_IRQ_ROUTE_WU_EN_SYS2 0x04000000
39 #define PDC_IRQ_ROUTE_WU_EN_SYS1 0x02000000
40 #define PDC_IRQ_ROUTE_WU_EN_SYS0 0x01000000
41 #define PDC_IRQ_ROUTE_WU_EN_WD 0x00040000
42 #define PDC_IRQ_ROUTE_WU_EN_IR 0x00020000
43 #define PDC_IRQ_ROUTE_WU_EN_RTC 0x00010000
44 #define PDC_IRQ_ROUTE_EXT_EN_SYS3 0x00000800
45 #define PDC_IRQ_ROUTE_EXT_EN_SYS2 0x00000400
46 #define PDC_IRQ_ROUTE_EXT_EN_SYS1 0x00000200
47 #define PDC_IRQ_ROUTE_EXT_EN_SYS0 0x00000100
48 #define PDC_IRQ_ROUTE_EXT_EN_WD 0x00000004
49 #define PDC_IRQ_ROUTE_EXT_EN_IR 0x00000002
50 #define PDC_IRQ_ROUTE_EXT_EN_RTC 0x00000001
51 #define PDC_SYS_WAKE_RESET 0x00000010
52 #define PDC_SYS_WAKE_INT_MODE 0x0000000e
53 #define PDC_SYS_WAKE_INT_MODE_SHIFT 1
54 #define PDC_SYS_WAKE_PIN_VAL 0x00000001
55
56 /* PDC interrupt constants */
57
58 #define PDC_SYS_WAKE_INT_LOW 0x0
59 #define PDC_SYS_WAKE_INT_HIGH 0x1
60 #define PDC_SYS_WAKE_INT_DOWN 0x2
61 #define PDC_SYS_WAKE_INT_UP 0x3
62 #define PDC_SYS_WAKE_INT_CHANGE 0x6
63 #define PDC_SYS_WAKE_INT_NONE 0x4
64
65 /**
66 * struct pdc_intc_priv - private pdc interrupt data.
67 * @nr_perips: Number of peripheral interrupt signals.
68 * @nr_syswakes: Number of syswake signals.
69 * @perip_irqs: List of peripheral IRQ numbers handled.
70 * @syswake_irq: Shared PDC syswake IRQ number.
71 * @domain: IRQ domain for PDC peripheral and syswake IRQs.
72 * @pdc_base: Base of PDC registers.
73 * @irq_route: Cached version of PDC_IRQ_ROUTE register.
74 * @lock: Lock to protect the PDC syswake registers and the cached
75 * values of those registers in this struct.
76 */
77 struct pdc_intc_priv {
78 unsigned int nr_perips;
79 unsigned int nr_syswakes;
80 unsigned int *perip_irqs;
81 unsigned int syswake_irq;
82 struct irq_domain *domain;
83 void __iomem *pdc_base;
84
85 u32 irq_route;
86 raw_spinlock_t lock;
87 };
88
pdc_write(struct pdc_intc_priv * priv,unsigned int reg_offs,unsigned int data)89 static void pdc_write(struct pdc_intc_priv *priv, unsigned int reg_offs,
90 unsigned int data)
91 {
92 iowrite32(data, priv->pdc_base + reg_offs);
93 }
94
pdc_read(struct pdc_intc_priv * priv,unsigned int reg_offs)95 static unsigned int pdc_read(struct pdc_intc_priv *priv,
96 unsigned int reg_offs)
97 {
98 return ioread32(priv->pdc_base + reg_offs);
99 }
100
101 /* Generic IRQ callbacks */
102
103 #define SYS0_HWIRQ 8
104
hwirq_is_syswake(irq_hw_number_t hw)105 static unsigned int hwirq_is_syswake(irq_hw_number_t hw)
106 {
107 return hw >= SYS0_HWIRQ;
108 }
109
hwirq_to_syswake(irq_hw_number_t hw)110 static unsigned int hwirq_to_syswake(irq_hw_number_t hw)
111 {
112 return hw - SYS0_HWIRQ;
113 }
114
syswake_to_hwirq(unsigned int syswake)115 static irq_hw_number_t syswake_to_hwirq(unsigned int syswake)
116 {
117 return SYS0_HWIRQ + syswake;
118 }
119
irqd_to_priv(struct irq_data * data)120 static struct pdc_intc_priv *irqd_to_priv(struct irq_data *data)
121 {
122 return (struct pdc_intc_priv *)data->domain->host_data;
123 }
124
125 /*
126 * perip_irq_mask() and perip_irq_unmask() use IRQ_ROUTE which also contains
127 * wake bits, therefore we cannot use the generic irqchip mask callbacks as they
128 * cache the mask.
129 */
130
perip_irq_mask(struct irq_data * data)131 static void perip_irq_mask(struct irq_data *data)
132 {
133 struct pdc_intc_priv *priv = irqd_to_priv(data);
134
135 raw_spin_lock(&priv->lock);
136 priv->irq_route &= ~data->mask;
137 pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
138 raw_spin_unlock(&priv->lock);
139 }
140
perip_irq_unmask(struct irq_data * data)141 static void perip_irq_unmask(struct irq_data *data)
142 {
143 struct pdc_intc_priv *priv = irqd_to_priv(data);
144
145 raw_spin_lock(&priv->lock);
146 priv->irq_route |= data->mask;
147 pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
148 raw_spin_unlock(&priv->lock);
149 }
150
syswake_irq_set_type(struct irq_data * data,unsigned int flow_type)151 static int syswake_irq_set_type(struct irq_data *data, unsigned int flow_type)
152 {
153 struct pdc_intc_priv *priv = irqd_to_priv(data);
154 unsigned int syswake = hwirq_to_syswake(data->hwirq);
155 unsigned int irq_mode;
156 unsigned int soc_sys_wake_regoff, soc_sys_wake;
157
158 /* translate to syswake IRQ mode */
159 switch (flow_type) {
160 case IRQ_TYPE_EDGE_BOTH:
161 irq_mode = PDC_SYS_WAKE_INT_CHANGE;
162 break;
163 case IRQ_TYPE_EDGE_RISING:
164 irq_mode = PDC_SYS_WAKE_INT_UP;
165 break;
166 case IRQ_TYPE_EDGE_FALLING:
167 irq_mode = PDC_SYS_WAKE_INT_DOWN;
168 break;
169 case IRQ_TYPE_LEVEL_HIGH:
170 irq_mode = PDC_SYS_WAKE_INT_HIGH;
171 break;
172 case IRQ_TYPE_LEVEL_LOW:
173 irq_mode = PDC_SYS_WAKE_INT_LOW;
174 break;
175 default:
176 return -EINVAL;
177 }
178
179 raw_spin_lock(&priv->lock);
180
181 /* set the IRQ mode */
182 soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + syswake*PDC_SYS_WAKE_STRIDE;
183 soc_sys_wake = pdc_read(priv, soc_sys_wake_regoff);
184 soc_sys_wake &= ~PDC_SYS_WAKE_INT_MODE;
185 soc_sys_wake |= irq_mode << PDC_SYS_WAKE_INT_MODE_SHIFT;
186 pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
187
188 /* and update the handler */
189 irq_setup_alt_chip(data, flow_type);
190
191 raw_spin_unlock(&priv->lock);
192
193 return 0;
194 }
195
196 /* applies to both peripheral and syswake interrupts */
pdc_irq_set_wake(struct irq_data * data,unsigned int on)197 static int pdc_irq_set_wake(struct irq_data *data, unsigned int on)
198 {
199 struct pdc_intc_priv *priv = irqd_to_priv(data);
200 irq_hw_number_t hw = data->hwirq;
201 unsigned int mask = (1 << 16) << hw;
202 unsigned int dst_irq;
203
204 raw_spin_lock(&priv->lock);
205 if (on)
206 priv->irq_route |= mask;
207 else
208 priv->irq_route &= ~mask;
209 pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
210 raw_spin_unlock(&priv->lock);
211
212 /* control the destination IRQ wakeup too for standby mode */
213 if (hwirq_is_syswake(hw))
214 dst_irq = priv->syswake_irq;
215 else
216 dst_irq = priv->perip_irqs[hw];
217 irq_set_irq_wake(dst_irq, on);
218
219 return 0;
220 }
221
pdc_intc_perip_isr(struct irq_desc * desc)222 static void pdc_intc_perip_isr(struct irq_desc *desc)
223 {
224 unsigned int irq = irq_desc_get_irq(desc);
225 struct pdc_intc_priv *priv;
226 unsigned int i;
227
228 priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
229
230 /* find the peripheral number */
231 for (i = 0; i < priv->nr_perips; ++i)
232 if (irq == priv->perip_irqs[i])
233 goto found;
234
235 /* should never get here */
236 return;
237 found:
238
239 /* pass on the interrupt */
240 generic_handle_domain_irq(priv->domain, i);
241 }
242
pdc_intc_syswake_isr(struct irq_desc * desc)243 static void pdc_intc_syswake_isr(struct irq_desc *desc)
244 {
245 struct pdc_intc_priv *priv;
246 unsigned int syswake;
247 unsigned int status;
248
249 priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
250
251 status = pdc_read(priv, PDC_IRQ_STATUS) &
252 pdc_read(priv, PDC_IRQ_ENABLE);
253 status &= (1 << priv->nr_syswakes) - 1;
254
255 for (syswake = 0; status; status >>= 1, ++syswake) {
256 /* Has this sys_wake triggered? */
257 if (!(status & 1))
258 continue;
259
260 generic_handle_domain_irq(priv->domain, syswake_to_hwirq(syswake));
261 }
262 }
263
pdc_intc_setup(struct pdc_intc_priv * priv)264 static void pdc_intc_setup(struct pdc_intc_priv *priv)
265 {
266 int i;
267 unsigned int soc_sys_wake_regoff;
268 unsigned int soc_sys_wake;
269
270 /*
271 * Mask all syswake interrupts before routing, or we could receive an
272 * interrupt before we're ready to handle it.
273 */
274 pdc_write(priv, PDC_IRQ_ENABLE, 0);
275
276 /*
277 * Enable routing of all syswakes
278 * Disable all wake sources
279 */
280 priv->irq_route = ((PDC_IRQ_ROUTE_EXT_EN_SYS0 << priv->nr_syswakes) -
281 PDC_IRQ_ROUTE_EXT_EN_SYS0);
282 pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
283
284 /* Initialise syswake IRQ */
285 for (i = 0; i < priv->nr_syswakes; ++i) {
286 /* set the IRQ mode to none */
287 soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + i*PDC_SYS_WAKE_STRIDE;
288 soc_sys_wake = PDC_SYS_WAKE_INT_NONE
289 << PDC_SYS_WAKE_INT_MODE_SHIFT;
290 pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
291 }
292 }
293
pdc_intc_probe(struct platform_device * pdev)294 static int pdc_intc_probe(struct platform_device *pdev)
295 {
296 struct pdc_intc_priv *priv;
297 struct device_node *node = pdev->dev.of_node;
298 struct resource *res_regs;
299 struct irq_chip_generic *gc;
300 unsigned int i;
301 int irq, ret;
302 u32 val;
303
304 if (!node)
305 return -ENOENT;
306
307 /* Get registers */
308 res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
309 if (res_regs == NULL) {
310 dev_err(&pdev->dev, "cannot find registers resource\n");
311 return -ENOENT;
312 }
313
314 /* Allocate driver data */
315 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
316 if (!priv)
317 return -ENOMEM;
318 raw_spin_lock_init(&priv->lock);
319 platform_set_drvdata(pdev, priv);
320
321 /* Ioremap the registers */
322 priv->pdc_base = devm_ioremap(&pdev->dev, res_regs->start,
323 resource_size(res_regs));
324 if (!priv->pdc_base)
325 return -EIO;
326
327 /* Get number of peripherals */
328 ret = of_property_read_u32(node, "num-perips", &val);
329 if (ret) {
330 dev_err(&pdev->dev, "No num-perips node property found\n");
331 return -EINVAL;
332 }
333 if (val > SYS0_HWIRQ) {
334 dev_err(&pdev->dev, "num-perips (%u) out of range\n", val);
335 return -EINVAL;
336 }
337 priv->nr_perips = val;
338
339 /* Get number of syswakes */
340 ret = of_property_read_u32(node, "num-syswakes", &val);
341 if (ret) {
342 dev_err(&pdev->dev, "No num-syswakes node property found\n");
343 return -EINVAL;
344 }
345 if (val > SYS0_HWIRQ) {
346 dev_err(&pdev->dev, "num-syswakes (%u) out of range\n", val);
347 return -EINVAL;
348 }
349 priv->nr_syswakes = val;
350
351 /* Get peripheral IRQ numbers */
352 priv->perip_irqs = devm_kcalloc(&pdev->dev, 4, priv->nr_perips,
353 GFP_KERNEL);
354 if (!priv->perip_irqs)
355 return -ENOMEM;
356 for (i = 0; i < priv->nr_perips; ++i) {
357 irq = platform_get_irq(pdev, 1 + i);
358 if (irq < 0)
359 return irq;
360 priv->perip_irqs[i] = irq;
361 }
362 /* check if too many were provided */
363 if (platform_get_irq(pdev, 1 + i) >= 0) {
364 dev_err(&pdev->dev, "surplus perip IRQs detected\n");
365 return -EINVAL;
366 }
367
368 /* Get syswake IRQ number */
369 irq = platform_get_irq(pdev, 0);
370 if (irq < 0)
371 return irq;
372 priv->syswake_irq = irq;
373
374 /* Set up an IRQ domain */
375 priv->domain = irq_domain_add_linear(node, 16, &irq_generic_chip_ops,
376 priv);
377 if (unlikely(!priv->domain)) {
378 dev_err(&pdev->dev, "cannot add IRQ domain\n");
379 return -ENOMEM;
380 }
381
382 /*
383 * Set up 2 generic irq chips with 2 chip types.
384 * The first one for peripheral irqs (only 1 chip type used)
385 * The second one for syswake irqs (edge and level chip types)
386 */
387 ret = irq_alloc_domain_generic_chips(priv->domain, 8, 2, "pdc",
388 handle_level_irq, 0, 0,
389 IRQ_GC_INIT_NESTED_LOCK);
390 if (ret)
391 goto err_generic;
392
393 /* peripheral interrupt chip */
394
395 gc = irq_get_domain_generic_chip(priv->domain, 0);
396 gc->unused = ~(BIT(priv->nr_perips) - 1);
397 gc->reg_base = priv->pdc_base;
398 /*
399 * IRQ_ROUTE contains wake bits, so we can't use the generic versions as
400 * they cache the mask
401 */
402 gc->chip_types[0].regs.mask = PDC_IRQ_ROUTE;
403 gc->chip_types[0].chip.irq_mask = perip_irq_mask;
404 gc->chip_types[0].chip.irq_unmask = perip_irq_unmask;
405 gc->chip_types[0].chip.irq_set_wake = pdc_irq_set_wake;
406
407 /* syswake interrupt chip */
408
409 gc = irq_get_domain_generic_chip(priv->domain, 8);
410 gc->unused = ~(BIT(priv->nr_syswakes) - 1);
411 gc->reg_base = priv->pdc_base;
412
413 /* edge interrupts */
414 gc->chip_types[0].type = IRQ_TYPE_EDGE_BOTH;
415 gc->chip_types[0].handler = handle_edge_irq;
416 gc->chip_types[0].regs.ack = PDC_IRQ_CLEAR;
417 gc->chip_types[0].regs.mask = PDC_IRQ_ENABLE;
418 gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
419 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
420 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
421 gc->chip_types[0].chip.irq_set_type = syswake_irq_set_type;
422 gc->chip_types[0].chip.irq_set_wake = pdc_irq_set_wake;
423 /* for standby we pass on to the shared syswake IRQ */
424 gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
425
426 /* level interrupts */
427 gc->chip_types[1].type = IRQ_TYPE_LEVEL_MASK;
428 gc->chip_types[1].handler = handle_level_irq;
429 gc->chip_types[1].regs.ack = PDC_IRQ_CLEAR;
430 gc->chip_types[1].regs.mask = PDC_IRQ_ENABLE;
431 gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit;
432 gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit;
433 gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit;
434 gc->chip_types[1].chip.irq_set_type = syswake_irq_set_type;
435 gc->chip_types[1].chip.irq_set_wake = pdc_irq_set_wake;
436 /* for standby we pass on to the shared syswake IRQ */
437 gc->chip_types[1].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
438
439 /* Set up the hardware to enable interrupt routing */
440 pdc_intc_setup(priv);
441
442 /* Setup chained handlers for the peripheral IRQs */
443 for (i = 0; i < priv->nr_perips; ++i) {
444 irq = priv->perip_irqs[i];
445 irq_set_chained_handler_and_data(irq, pdc_intc_perip_isr,
446 priv);
447 }
448
449 /* Setup chained handler for the syswake IRQ */
450 irq_set_chained_handler_and_data(priv->syswake_irq,
451 pdc_intc_syswake_isr, priv);
452
453 dev_info(&pdev->dev,
454 "PDC IRQ controller initialised (%u perip IRQs, %u syswake IRQs)\n",
455 priv->nr_perips,
456 priv->nr_syswakes);
457
458 return 0;
459 err_generic:
460 irq_domain_remove(priv->domain);
461 return ret;
462 }
463
pdc_intc_remove(struct platform_device * pdev)464 static void pdc_intc_remove(struct platform_device *pdev)
465 {
466 struct pdc_intc_priv *priv = platform_get_drvdata(pdev);
467
468 irq_domain_remove(priv->domain);
469 }
470
471 static const struct of_device_id pdc_intc_match[] = {
472 { .compatible = "img,pdc-intc" },
473 {}
474 };
475
476 static struct platform_driver pdc_intc_driver = {
477 .driver = {
478 .name = "pdc-intc",
479 .of_match_table = pdc_intc_match,
480 },
481 .probe = pdc_intc_probe,
482 .remove_new = pdc_intc_remove,
483 };
484
pdc_intc_init(void)485 static int __init pdc_intc_init(void)
486 {
487 return platform_driver_register(&pdc_intc_driver);
488 }
489 core_initcall(pdc_intc_init);
490