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