1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2017-2019, The Linux Foundation. All rights reserved.
4 */
5
6 #include <linux/err.h>
7 #include <linux/init.h>
8 #include <linux/interrupt.h>
9 #include <linux/irq.h>
10 #include <linux/irqchip.h>
11 #include <linux/irqdomain.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_device.h>
18 #include <linux/of_irq.h>
19 #include <linux/soc/qcom/irq.h>
20 #include <linux/spinlock.h>
21 #include <linux/slab.h>
22 #include <linux/types.h>
23
24 #define PDC_MAX_IRQS 168
25 #define PDC_MAX_GPIO_IRQS 256
26
27 #define CLEAR_INTR(reg, intr) (reg & ~(1 << intr))
28 #define ENABLE_INTR(reg, intr) (reg | (1 << intr))
29
30 #define IRQ_ENABLE_BANK 0x10
31 #define IRQ_i_CFG 0x110
32
33 #define PDC_NO_PARENT_IRQ ~0UL
34
35 struct pdc_pin_region {
36 u32 pin_base;
37 u32 parent_base;
38 u32 cnt;
39 };
40
41 static DEFINE_RAW_SPINLOCK(pdc_lock);
42 static void __iomem *pdc_base;
43 static struct pdc_pin_region *pdc_region;
44 static int pdc_region_cnt;
45
pdc_reg_write(int reg,u32 i,u32 val)46 static void pdc_reg_write(int reg, u32 i, u32 val)
47 {
48 writel_relaxed(val, pdc_base + reg + i * sizeof(u32));
49 }
50
pdc_reg_read(int reg,u32 i)51 static u32 pdc_reg_read(int reg, u32 i)
52 {
53 return readl_relaxed(pdc_base + reg + i * sizeof(u32));
54 }
55
pdc_enable_intr(struct irq_data * d,bool on)56 static void pdc_enable_intr(struct irq_data *d, bool on)
57 {
58 int pin_out = d->hwirq;
59 unsigned long flags;
60 u32 index, mask;
61 u32 enable;
62
63 index = pin_out / 32;
64 mask = pin_out % 32;
65
66 raw_spin_lock_irqsave(&pdc_lock, flags);
67 enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
68 enable = on ? ENABLE_INTR(enable, mask) : CLEAR_INTR(enable, mask);
69 pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
70 raw_spin_unlock_irqrestore(&pdc_lock, flags);
71 }
72
qcom_pdc_gic_disable(struct irq_data * d)73 static void qcom_pdc_gic_disable(struct irq_data *d)
74 {
75 pdc_enable_intr(d, false);
76 irq_chip_disable_parent(d);
77 }
78
qcom_pdc_gic_enable(struct irq_data * d)79 static void qcom_pdc_gic_enable(struct irq_data *d)
80 {
81 pdc_enable_intr(d, true);
82 irq_chip_enable_parent(d);
83 }
84
85 /*
86 * GIC does not handle falling edge or active low. To allow falling edge and
87 * active low interrupts to be handled at GIC, PDC has an inverter that inverts
88 * falling edge into a rising edge and active low into an active high.
89 * For the inverter to work, the polarity bit in the IRQ_CONFIG register has to
90 * set as per the table below.
91 * Level sensitive active low LOW
92 * Rising edge sensitive NOT USED
93 * Falling edge sensitive LOW
94 * Dual Edge sensitive NOT USED
95 * Level sensitive active High HIGH
96 * Falling Edge sensitive NOT USED
97 * Rising edge sensitive HIGH
98 * Dual Edge sensitive HIGH
99 */
100 enum pdc_irq_config_bits {
101 PDC_LEVEL_LOW = 0b000,
102 PDC_EDGE_FALLING = 0b010,
103 PDC_LEVEL_HIGH = 0b100,
104 PDC_EDGE_RISING = 0b110,
105 PDC_EDGE_DUAL = 0b111,
106 };
107
108 /**
109 * qcom_pdc_gic_set_type: Configure PDC for the interrupt
110 *
111 * @d: the interrupt data
112 * @type: the interrupt type
113 *
114 * If @type is edge triggered, forward that as Rising edge as PDC
115 * takes care of converting falling edge to rising edge signal
116 * If @type is level, then forward that as level high as PDC
117 * takes care of converting falling edge to rising edge signal
118 */
qcom_pdc_gic_set_type(struct irq_data * d,unsigned int type)119 static int qcom_pdc_gic_set_type(struct irq_data *d, unsigned int type)
120 {
121 enum pdc_irq_config_bits pdc_type;
122 enum pdc_irq_config_bits old_pdc_type;
123 int ret;
124
125 switch (type) {
126 case IRQ_TYPE_EDGE_RISING:
127 pdc_type = PDC_EDGE_RISING;
128 break;
129 case IRQ_TYPE_EDGE_FALLING:
130 pdc_type = PDC_EDGE_FALLING;
131 type = IRQ_TYPE_EDGE_RISING;
132 break;
133 case IRQ_TYPE_EDGE_BOTH:
134 pdc_type = PDC_EDGE_DUAL;
135 type = IRQ_TYPE_EDGE_RISING;
136 break;
137 case IRQ_TYPE_LEVEL_HIGH:
138 pdc_type = PDC_LEVEL_HIGH;
139 break;
140 case IRQ_TYPE_LEVEL_LOW:
141 pdc_type = PDC_LEVEL_LOW;
142 type = IRQ_TYPE_LEVEL_HIGH;
143 break;
144 default:
145 WARN_ON(1);
146 return -EINVAL;
147 }
148
149 old_pdc_type = pdc_reg_read(IRQ_i_CFG, d->hwirq);
150 pdc_reg_write(IRQ_i_CFG, d->hwirq, pdc_type);
151
152 ret = irq_chip_set_type_parent(d, type);
153 if (ret)
154 return ret;
155
156 /*
157 * When we change types the PDC can give a phantom interrupt.
158 * Clear it. Specifically the phantom shows up when reconfiguring
159 * polarity of interrupt without changing the state of the signal
160 * but let's be consistent and clear it always.
161 *
162 * Doing this works because we have IRQCHIP_SET_TYPE_MASKED so the
163 * interrupt will be cleared before the rest of the system sees it.
164 */
165 if (old_pdc_type != pdc_type)
166 irq_chip_set_parent_state(d, IRQCHIP_STATE_PENDING, false);
167
168 return 0;
169 }
170
171 static struct irq_chip qcom_pdc_gic_chip = {
172 .name = "PDC",
173 .irq_eoi = irq_chip_eoi_parent,
174 .irq_mask = irq_chip_mask_parent,
175 .irq_unmask = irq_chip_unmask_parent,
176 .irq_disable = qcom_pdc_gic_disable,
177 .irq_enable = qcom_pdc_gic_enable,
178 .irq_get_irqchip_state = irq_chip_get_parent_state,
179 .irq_set_irqchip_state = irq_chip_set_parent_state,
180 .irq_retrigger = irq_chip_retrigger_hierarchy,
181 .irq_set_type = qcom_pdc_gic_set_type,
182 .flags = IRQCHIP_MASK_ON_SUSPEND |
183 IRQCHIP_SET_TYPE_MASKED |
184 IRQCHIP_SKIP_SET_WAKE |
185 IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND,
186 .irq_set_vcpu_affinity = irq_chip_set_vcpu_affinity_parent,
187 .irq_set_affinity = irq_chip_set_affinity_parent,
188 };
189
get_parent_hwirq(int pin)190 static irq_hw_number_t get_parent_hwirq(int pin)
191 {
192 int i;
193 struct pdc_pin_region *region;
194
195 for (i = 0; i < pdc_region_cnt; i++) {
196 region = &pdc_region[i];
197 if (pin >= region->pin_base &&
198 pin < region->pin_base + region->cnt)
199 return (region->parent_base + pin - region->pin_base);
200 }
201
202 return PDC_NO_PARENT_IRQ;
203 }
204
qcom_pdc_translate(struct irq_domain * d,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)205 static int qcom_pdc_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
206 unsigned long *hwirq, unsigned int *type)
207 {
208 if (is_of_node(fwspec->fwnode)) {
209 if (fwspec->param_count != 2)
210 return -EINVAL;
211
212 *hwirq = fwspec->param[0];
213 *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
214 return 0;
215 }
216
217 return -EINVAL;
218 }
219
qcom_pdc_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * data)220 static int qcom_pdc_alloc(struct irq_domain *domain, unsigned int virq,
221 unsigned int nr_irqs, void *data)
222 {
223 struct irq_fwspec *fwspec = data;
224 struct irq_fwspec parent_fwspec;
225 irq_hw_number_t hwirq, parent_hwirq;
226 unsigned int type;
227 int ret;
228
229 ret = qcom_pdc_translate(domain, fwspec, &hwirq, &type);
230 if (ret)
231 return ret;
232
233 ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
234 &qcom_pdc_gic_chip, NULL);
235 if (ret)
236 return ret;
237
238 parent_hwirq = get_parent_hwirq(hwirq);
239 if (parent_hwirq == PDC_NO_PARENT_IRQ)
240 return irq_domain_disconnect_hierarchy(domain->parent, virq);
241
242 if (type & IRQ_TYPE_EDGE_BOTH)
243 type = IRQ_TYPE_EDGE_RISING;
244
245 if (type & IRQ_TYPE_LEVEL_MASK)
246 type = IRQ_TYPE_LEVEL_HIGH;
247
248 parent_fwspec.fwnode = domain->parent->fwnode;
249 parent_fwspec.param_count = 3;
250 parent_fwspec.param[0] = 0;
251 parent_fwspec.param[1] = parent_hwirq;
252 parent_fwspec.param[2] = type;
253
254 return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
255 &parent_fwspec);
256 }
257
258 static const struct irq_domain_ops qcom_pdc_ops = {
259 .translate = qcom_pdc_translate,
260 .alloc = qcom_pdc_alloc,
261 .free = irq_domain_free_irqs_common,
262 };
263
qcom_pdc_gpio_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * data)264 static int qcom_pdc_gpio_alloc(struct irq_domain *domain, unsigned int virq,
265 unsigned int nr_irqs, void *data)
266 {
267 struct irq_fwspec *fwspec = data;
268 struct irq_fwspec parent_fwspec;
269 irq_hw_number_t hwirq, parent_hwirq;
270 unsigned int type;
271 int ret;
272
273 ret = qcom_pdc_translate(domain, fwspec, &hwirq, &type);
274 if (ret)
275 return ret;
276
277 if (hwirq == GPIO_NO_WAKE_IRQ)
278 return irq_domain_disconnect_hierarchy(domain, virq);
279
280 ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
281 &qcom_pdc_gic_chip, NULL);
282 if (ret)
283 return ret;
284
285 parent_hwirq = get_parent_hwirq(hwirq);
286 if (parent_hwirq == PDC_NO_PARENT_IRQ)
287 return irq_domain_disconnect_hierarchy(domain->parent, virq);
288
289 if (type & IRQ_TYPE_EDGE_BOTH)
290 type = IRQ_TYPE_EDGE_RISING;
291
292 if (type & IRQ_TYPE_LEVEL_MASK)
293 type = IRQ_TYPE_LEVEL_HIGH;
294
295 parent_fwspec.fwnode = domain->parent->fwnode;
296 parent_fwspec.param_count = 3;
297 parent_fwspec.param[0] = 0;
298 parent_fwspec.param[1] = parent_hwirq;
299 parent_fwspec.param[2] = type;
300
301 return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
302 &parent_fwspec);
303 }
304
qcom_pdc_gpio_domain_select(struct irq_domain * d,struct irq_fwspec * fwspec,enum irq_domain_bus_token bus_token)305 static int qcom_pdc_gpio_domain_select(struct irq_domain *d,
306 struct irq_fwspec *fwspec,
307 enum irq_domain_bus_token bus_token)
308 {
309 return bus_token == DOMAIN_BUS_WAKEUP;
310 }
311
312 static const struct irq_domain_ops qcom_pdc_gpio_ops = {
313 .select = qcom_pdc_gpio_domain_select,
314 .alloc = qcom_pdc_gpio_alloc,
315 .free = irq_domain_free_irqs_common,
316 };
317
pdc_setup_pin_mapping(struct device_node * np)318 static int pdc_setup_pin_mapping(struct device_node *np)
319 {
320 int ret, n, i;
321 u32 irq_index, reg_index, val;
322
323 n = of_property_count_elems_of_size(np, "qcom,pdc-ranges", sizeof(u32));
324 if (n <= 0 || n % 3)
325 return -EINVAL;
326
327 pdc_region_cnt = n / 3;
328 pdc_region = kcalloc(pdc_region_cnt, sizeof(*pdc_region), GFP_KERNEL);
329 if (!pdc_region) {
330 pdc_region_cnt = 0;
331 return -ENOMEM;
332 }
333
334 for (n = 0; n < pdc_region_cnt; n++) {
335 ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
336 n * 3 + 0,
337 &pdc_region[n].pin_base);
338 if (ret)
339 return ret;
340 ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
341 n * 3 + 1,
342 &pdc_region[n].parent_base);
343 if (ret)
344 return ret;
345 ret = of_property_read_u32_index(np, "qcom,pdc-ranges",
346 n * 3 + 2,
347 &pdc_region[n].cnt);
348 if (ret)
349 return ret;
350
351 for (i = 0; i < pdc_region[n].cnt; i++) {
352 reg_index = (i + pdc_region[n].pin_base) >> 5;
353 irq_index = (i + pdc_region[n].pin_base) & 0x1f;
354 val = pdc_reg_read(IRQ_ENABLE_BANK, reg_index);
355 val &= ~BIT(irq_index);
356 pdc_reg_write(IRQ_ENABLE_BANK, reg_index, val);
357 }
358 }
359
360 return 0;
361 }
362
qcom_pdc_init(struct device_node * node,struct device_node * parent)363 static int qcom_pdc_init(struct device_node *node, struct device_node *parent)
364 {
365 struct irq_domain *parent_domain, *pdc_domain, *pdc_gpio_domain;
366 int ret;
367
368 pdc_base = of_iomap(node, 0);
369 if (!pdc_base) {
370 pr_err("%pOF: unable to map PDC registers\n", node);
371 return -ENXIO;
372 }
373
374 parent_domain = irq_find_host(parent);
375 if (!parent_domain) {
376 pr_err("%pOF: unable to find PDC's parent domain\n", node);
377 ret = -ENXIO;
378 goto fail;
379 }
380
381 ret = pdc_setup_pin_mapping(node);
382 if (ret) {
383 pr_err("%pOF: failed to init PDC pin-hwirq mapping\n", node);
384 goto fail;
385 }
386
387 pdc_domain = irq_domain_create_hierarchy(parent_domain, 0, PDC_MAX_IRQS,
388 of_fwnode_handle(node),
389 &qcom_pdc_ops, NULL);
390 if (!pdc_domain) {
391 pr_err("%pOF: GIC domain add failed\n", node);
392 ret = -ENOMEM;
393 goto fail;
394 }
395
396 pdc_gpio_domain = irq_domain_create_hierarchy(parent_domain,
397 IRQ_DOMAIN_FLAG_QCOM_PDC_WAKEUP,
398 PDC_MAX_GPIO_IRQS,
399 of_fwnode_handle(node),
400 &qcom_pdc_gpio_ops, NULL);
401 if (!pdc_gpio_domain) {
402 pr_err("%pOF: PDC domain add failed for GPIO domain\n", node);
403 ret = -ENOMEM;
404 goto remove;
405 }
406
407 irq_domain_update_bus_token(pdc_gpio_domain, DOMAIN_BUS_WAKEUP);
408
409 return 0;
410
411 remove:
412 irq_domain_remove(pdc_domain);
413 fail:
414 kfree(pdc_region);
415 iounmap(pdc_base);
416 return ret;
417 }
418
419 IRQCHIP_PLATFORM_DRIVER_BEGIN(qcom_pdc)
420 IRQCHIP_MATCH("qcom,pdc", qcom_pdc_init)
421 IRQCHIP_PLATFORM_DRIVER_END(qcom_pdc)
422 MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Power Domain Controller");
423 MODULE_LICENSE("GPL v2");
424