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, irq_no;
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 irq_no = irq_linear_revmap(priv->domain, i);
241 generic_handle_irq(irq_no);
242 }
243
pdc_intc_syswake_isr(struct irq_desc * desc)244 static void pdc_intc_syswake_isr(struct irq_desc *desc)
245 {
246 struct pdc_intc_priv *priv;
247 unsigned int syswake, irq_no;
248 unsigned int status;
249
250 priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
251
252 status = pdc_read(priv, PDC_IRQ_STATUS) &
253 pdc_read(priv, PDC_IRQ_ENABLE);
254 status &= (1 << priv->nr_syswakes) - 1;
255
256 for (syswake = 0; status; status >>= 1, ++syswake) {
257 /* Has this sys_wake triggered? */
258 if (!(status & 1))
259 continue;
260
261 irq_no = irq_linear_revmap(priv->domain,
262 syswake_to_hwirq(syswake));
263 generic_handle_irq(irq_no);
264 }
265 }
266
pdc_intc_setup(struct pdc_intc_priv * priv)267 static void pdc_intc_setup(struct pdc_intc_priv *priv)
268 {
269 int i;
270 unsigned int soc_sys_wake_regoff;
271 unsigned int soc_sys_wake;
272
273 /*
274 * Mask all syswake interrupts before routing, or we could receive an
275 * interrupt before we're ready to handle it.
276 */
277 pdc_write(priv, PDC_IRQ_ENABLE, 0);
278
279 /*
280 * Enable routing of all syswakes
281 * Disable all wake sources
282 */
283 priv->irq_route = ((PDC_IRQ_ROUTE_EXT_EN_SYS0 << priv->nr_syswakes) -
284 PDC_IRQ_ROUTE_EXT_EN_SYS0);
285 pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
286
287 /* Initialise syswake IRQ */
288 for (i = 0; i < priv->nr_syswakes; ++i) {
289 /* set the IRQ mode to none */
290 soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + i*PDC_SYS_WAKE_STRIDE;
291 soc_sys_wake = PDC_SYS_WAKE_INT_NONE
292 << PDC_SYS_WAKE_INT_MODE_SHIFT;
293 pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
294 }
295 }
296
pdc_intc_probe(struct platform_device * pdev)297 static int pdc_intc_probe(struct platform_device *pdev)
298 {
299 struct pdc_intc_priv *priv;
300 struct device_node *node = pdev->dev.of_node;
301 struct resource *res_regs;
302 struct irq_chip_generic *gc;
303 unsigned int i;
304 int irq, ret;
305 u32 val;
306
307 if (!node)
308 return -ENOENT;
309
310 /* Get registers */
311 res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
312 if (res_regs == NULL) {
313 dev_err(&pdev->dev, "cannot find registers resource\n");
314 return -ENOENT;
315 }
316
317 /* Allocate driver data */
318 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
319 if (!priv) {
320 dev_err(&pdev->dev, "cannot allocate device data\n");
321 return -ENOMEM;
322 }
323 raw_spin_lock_init(&priv->lock);
324 platform_set_drvdata(pdev, priv);
325
326 /* Ioremap the registers */
327 priv->pdc_base = devm_ioremap(&pdev->dev, res_regs->start,
328 resource_size(res_regs));
329 if (!priv->pdc_base)
330 return -EIO;
331
332 /* Get number of peripherals */
333 ret = of_property_read_u32(node, "num-perips", &val);
334 if (ret) {
335 dev_err(&pdev->dev, "No num-perips node property found\n");
336 return -EINVAL;
337 }
338 if (val > SYS0_HWIRQ) {
339 dev_err(&pdev->dev, "num-perips (%u) out of range\n", val);
340 return -EINVAL;
341 }
342 priv->nr_perips = val;
343
344 /* Get number of syswakes */
345 ret = of_property_read_u32(node, "num-syswakes", &val);
346 if (ret) {
347 dev_err(&pdev->dev, "No num-syswakes node property found\n");
348 return -EINVAL;
349 }
350 if (val > SYS0_HWIRQ) {
351 dev_err(&pdev->dev, "num-syswakes (%u) out of range\n", val);
352 return -EINVAL;
353 }
354 priv->nr_syswakes = val;
355
356 /* Get peripheral IRQ numbers */
357 priv->perip_irqs = devm_kcalloc(&pdev->dev, 4, priv->nr_perips,
358 GFP_KERNEL);
359 if (!priv->perip_irqs) {
360 dev_err(&pdev->dev, "cannot allocate perip IRQ list\n");
361 return -ENOMEM;
362 }
363 for (i = 0; i < priv->nr_perips; ++i) {
364 irq = platform_get_irq(pdev, 1 + i);
365 if (irq < 0)
366 return irq;
367 priv->perip_irqs[i] = irq;
368 }
369 /* check if too many were provided */
370 if (platform_get_irq(pdev, 1 + i) >= 0) {
371 dev_err(&pdev->dev, "surplus perip IRQs detected\n");
372 return -EINVAL;
373 }
374
375 /* Get syswake IRQ number */
376 irq = platform_get_irq(pdev, 0);
377 if (irq < 0)
378 return irq;
379 priv->syswake_irq = irq;
380
381 /* Set up an IRQ domain */
382 priv->domain = irq_domain_add_linear(node, 16, &irq_generic_chip_ops,
383 priv);
384 if (unlikely(!priv->domain)) {
385 dev_err(&pdev->dev, "cannot add IRQ domain\n");
386 return -ENOMEM;
387 }
388
389 /*
390 * Set up 2 generic irq chips with 2 chip types.
391 * The first one for peripheral irqs (only 1 chip type used)
392 * The second one for syswake irqs (edge and level chip types)
393 */
394 ret = irq_alloc_domain_generic_chips(priv->domain, 8, 2, "pdc",
395 handle_level_irq, 0, 0,
396 IRQ_GC_INIT_NESTED_LOCK);
397 if (ret)
398 goto err_generic;
399
400 /* peripheral interrupt chip */
401
402 gc = irq_get_domain_generic_chip(priv->domain, 0);
403 gc->unused = ~(BIT(priv->nr_perips) - 1);
404 gc->reg_base = priv->pdc_base;
405 /*
406 * IRQ_ROUTE contains wake bits, so we can't use the generic versions as
407 * they cache the mask
408 */
409 gc->chip_types[0].regs.mask = PDC_IRQ_ROUTE;
410 gc->chip_types[0].chip.irq_mask = perip_irq_mask;
411 gc->chip_types[0].chip.irq_unmask = perip_irq_unmask;
412 gc->chip_types[0].chip.irq_set_wake = pdc_irq_set_wake;
413
414 /* syswake interrupt chip */
415
416 gc = irq_get_domain_generic_chip(priv->domain, 8);
417 gc->unused = ~(BIT(priv->nr_syswakes) - 1);
418 gc->reg_base = priv->pdc_base;
419
420 /* edge interrupts */
421 gc->chip_types[0].type = IRQ_TYPE_EDGE_BOTH;
422 gc->chip_types[0].handler = handle_edge_irq;
423 gc->chip_types[0].regs.ack = PDC_IRQ_CLEAR;
424 gc->chip_types[0].regs.mask = PDC_IRQ_ENABLE;
425 gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
426 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
427 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
428 gc->chip_types[0].chip.irq_set_type = syswake_irq_set_type;
429 gc->chip_types[0].chip.irq_set_wake = pdc_irq_set_wake;
430 /* for standby we pass on to the shared syswake IRQ */
431 gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
432
433 /* level interrupts */
434 gc->chip_types[1].type = IRQ_TYPE_LEVEL_MASK;
435 gc->chip_types[1].handler = handle_level_irq;
436 gc->chip_types[1].regs.ack = PDC_IRQ_CLEAR;
437 gc->chip_types[1].regs.mask = PDC_IRQ_ENABLE;
438 gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit;
439 gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit;
440 gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit;
441 gc->chip_types[1].chip.irq_set_type = syswake_irq_set_type;
442 gc->chip_types[1].chip.irq_set_wake = pdc_irq_set_wake;
443 /* for standby we pass on to the shared syswake IRQ */
444 gc->chip_types[1].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
445
446 /* Set up the hardware to enable interrupt routing */
447 pdc_intc_setup(priv);
448
449 /* Setup chained handlers for the peripheral IRQs */
450 for (i = 0; i < priv->nr_perips; ++i) {
451 irq = priv->perip_irqs[i];
452 irq_set_chained_handler_and_data(irq, pdc_intc_perip_isr,
453 priv);
454 }
455
456 /* Setup chained handler for the syswake IRQ */
457 irq_set_chained_handler_and_data(priv->syswake_irq,
458 pdc_intc_syswake_isr, priv);
459
460 dev_info(&pdev->dev,
461 "PDC IRQ controller initialised (%u perip IRQs, %u syswake IRQs)\n",
462 priv->nr_perips,
463 priv->nr_syswakes);
464
465 return 0;
466 err_generic:
467 irq_domain_remove(priv->domain);
468 return ret;
469 }
470
pdc_intc_remove(struct platform_device * pdev)471 static int pdc_intc_remove(struct platform_device *pdev)
472 {
473 struct pdc_intc_priv *priv = platform_get_drvdata(pdev);
474
475 irq_domain_remove(priv->domain);
476 return 0;
477 }
478
479 static const struct of_device_id pdc_intc_match[] = {
480 { .compatible = "img,pdc-intc" },
481 {}
482 };
483
484 static struct platform_driver pdc_intc_driver = {
485 .driver = {
486 .name = "pdc-intc",
487 .of_match_table = pdc_intc_match,
488 },
489 .probe = pdc_intc_probe,
490 .remove = pdc_intc_remove,
491 };
492
pdc_intc_init(void)493 static int __init pdc_intc_init(void)
494 {
495 return platform_driver_register(&pdc_intc_driver);
496 }
497 core_initcall(pdc_intc_init);
498