1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2016, 2017 Cavium Inc.
7 */
8
9#include <linux/bitops.h>
10#include <linux/gpio/driver.h>
11#include <linux/interrupt.h>
12#include <linux/io.h>
13#include <linux/irq.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/pci.h>
17#include <linux/spinlock.h>
18
19
20#define GPIO_RX_DAT 0x0
21#define GPIO_TX_SET 0x8
22#define GPIO_TX_CLR 0x10
23#define GPIO_CONST 0x90
24#define GPIO_CONST_GPIOS_MASK 0xff
25#define GPIO_BIT_CFG 0x400
26#define GPIO_BIT_CFG_TX_OE BIT(0)
27#define GPIO_BIT_CFG_PIN_XOR BIT(1)
28#define GPIO_BIT_CFG_INT_EN BIT(2)
29#define GPIO_BIT_CFG_INT_TYPE BIT(3)
30#define GPIO_BIT_CFG_FIL_MASK GENMASK(11, 4)
31#define GPIO_BIT_CFG_FIL_CNT_SHIFT 4
32#define GPIO_BIT_CFG_FIL_SEL_SHIFT 8
33#define GPIO_BIT_CFG_TX_OD BIT(12)
34#define GPIO_BIT_CFG_PIN_SEL_MASK GENMASK(25, 16)
35#define GPIO_INTR 0x800
36#define GPIO_INTR_INTR BIT(0)
37#define GPIO_INTR_INTR_W1S BIT(1)
38#define GPIO_INTR_ENA_W1C BIT(2)
39#define GPIO_INTR_ENA_W1S BIT(3)
40#define GPIO_2ND_BANK 0x1400
41
42#define GLITCH_FILTER_400NS ((4u << GPIO_BIT_CFG_FIL_SEL_SHIFT) | \
43 (9u << GPIO_BIT_CFG_FIL_CNT_SHIFT))
44
45struct thunderx_gpio;
46
47struct thunderx_line {
48 struct thunderx_gpio *txgpio;
49 unsigned int line;
50 unsigned int fil_bits;
51};
52
53struct thunderx_gpio {
54 struct gpio_chip chip;
55 u8 __iomem *register_base;
56 struct irq_domain *irqd;
57 struct msix_entry *msix_entries; /* per line MSI-X */
58 struct thunderx_line *line_entries; /* per line irq info */
59 raw_spinlock_t lock;
60 unsigned long invert_mask[2];
61 unsigned long od_mask[2];
62 int base_msi;
63};
64
65static unsigned int bit_cfg_reg(unsigned int line)
66{
67 return 8 * line + GPIO_BIT_CFG;
68}
69
70static unsigned int intr_reg(unsigned int line)
71{
72 return 8 * line + GPIO_INTR;
73}
74
75static bool thunderx_gpio_is_gpio_nowarn(struct thunderx_gpio *txgpio,
76 unsigned int line)
77{
78 u64 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
79
80 return (bit_cfg & GPIO_BIT_CFG_PIN_SEL_MASK) == 0;
81}
82
83/*
84 * Check (and WARN) that the pin is available for GPIO. We will not
85 * allow modification of the state of non-GPIO pins from this driver.
86 */
87static bool thunderx_gpio_is_gpio(struct thunderx_gpio *txgpio,
88 unsigned int line)
89{
90 bool rv = thunderx_gpio_is_gpio_nowarn(txgpio, line);
91
92 WARN_RATELIMIT(!rv, "Pin %d not available for GPIO\n", line);
93
94 return rv;
95}
96
97static int thunderx_gpio_request(struct gpio_chip *chip, unsigned int line)
98{
99 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
100
101 return thunderx_gpio_is_gpio(txgpio, line) ? 0 : -EIO;
102}
103
104static int thunderx_gpio_dir_in(struct gpio_chip *chip, unsigned int line)
105{
106 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
107
108 if (!thunderx_gpio_is_gpio(txgpio, line))
109 return -EIO;
110
111 raw_spin_lock(&txgpio->lock);
112 clear_bit(line, txgpio->invert_mask);
113 clear_bit(line, txgpio->od_mask);
114 writeq(txgpio->line_entries[line].fil_bits,
115 txgpio->register_base + bit_cfg_reg(line));
116 raw_spin_unlock(&txgpio->lock);
117 return 0;
118}
119
120static void thunderx_gpio_set(struct gpio_chip *chip, unsigned int line,
121 int value)
122{
123 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
124 int bank = line / 64;
125 int bank_bit = line % 64;
126
127 void __iomem *reg = txgpio->register_base +
128 (bank * GPIO_2ND_BANK) + (value ? GPIO_TX_SET : GPIO_TX_CLR);
129
130 writeq(BIT_ULL(bank_bit), reg);
131}
132
133static int thunderx_gpio_dir_out(struct gpio_chip *chip, unsigned int line,
134 int value)
135{
136 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
137 u64 bit_cfg = txgpio->line_entries[line].fil_bits | GPIO_BIT_CFG_TX_OE;
138
139 if (!thunderx_gpio_is_gpio(txgpio, line))
140 return -EIO;
141
142 raw_spin_lock(&txgpio->lock);
143
144 thunderx_gpio_set(chip, line, value);
145
146 if (test_bit(line, txgpio->invert_mask))
147 bit_cfg |= GPIO_BIT_CFG_PIN_XOR;
148
149 if (test_bit(line, txgpio->od_mask))
150 bit_cfg |= GPIO_BIT_CFG_TX_OD;
151
152 writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(line));
153
154 raw_spin_unlock(&txgpio->lock);
155 return 0;
156}
157
158static int thunderx_gpio_get_direction(struct gpio_chip *chip, unsigned int line)
159{
160 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
161 u64 bit_cfg;
162
163 if (!thunderx_gpio_is_gpio_nowarn(txgpio, line))
164 /*
165 * Say it is input for now to avoid WARNing on
166 * gpiochip_add_data(). We will WARN if someone
167 * requests it or tries to use it.
168 */
169 return 1;
170
171 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
172
173 return !(bit_cfg & GPIO_BIT_CFG_TX_OE);
174}
175
176static int thunderx_gpio_set_config(struct gpio_chip *chip,
177 unsigned int line,
178 unsigned long cfg)
179{
180 bool orig_invert, orig_od, orig_dat, new_invert, new_od;
181 u32 arg, sel;
182 u64 bit_cfg;
183 int bank = line / 64;
184 int bank_bit = line % 64;
185 int ret = -ENOTSUPP;
186 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
187 void __iomem *reg = txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET;
188
189 if (!thunderx_gpio_is_gpio(txgpio, line))
190 return -EIO;
191
192 raw_spin_lock(&txgpio->lock);
193 orig_invert = test_bit(line, txgpio->invert_mask);
194 new_invert = orig_invert;
195 orig_od = test_bit(line, txgpio->od_mask);
196 new_od = orig_od;
197 orig_dat = ((readq(reg) >> bank_bit) & 1) ^ orig_invert;
198 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
199 switch (pinconf_to_config_param(cfg)) {
200 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
201 /*
202 * Weird, setting open-drain mode causes signal
203 * inversion. Note this so we can compensate in the
204 * dir_out function.
205 */
206 set_bit(line, txgpio->invert_mask);
207 new_invert = true;
208 set_bit(line, txgpio->od_mask);
209 new_od = true;
210 ret = 0;
211 break;
212 case PIN_CONFIG_DRIVE_PUSH_PULL:
213 clear_bit(line, txgpio->invert_mask);
214 new_invert = false;
215 clear_bit(line, txgpio->od_mask);
216 new_od = false;
217 ret = 0;
218 break;
219 case PIN_CONFIG_INPUT_DEBOUNCE:
220 arg = pinconf_to_config_argument(cfg);
221 if (arg > 1228) { /* 15 * 2^15 * 2.5nS maximum */
222 ret = -EINVAL;
223 break;
224 }
225 arg *= 400; /* scale to 2.5nS clocks. */
226 sel = 0;
227 while (arg > 15) {
228 sel++;
229 arg++; /* always round up */
230 arg >>= 1;
231 }
232 txgpio->line_entries[line].fil_bits =
233 (sel << GPIO_BIT_CFG_FIL_SEL_SHIFT) |
234 (arg << GPIO_BIT_CFG_FIL_CNT_SHIFT);
235 bit_cfg &= ~GPIO_BIT_CFG_FIL_MASK;
236 bit_cfg |= txgpio->line_entries[line].fil_bits;
237 writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(line));
238 ret = 0;
239 break;
240 default:
241 break;
242 }
243 raw_spin_unlock(&txgpio->lock);
244
245 /*
246 * If currently output and OPEN_DRAIN changed, install the new
247 * settings
248 */
249 if ((new_invert != orig_invert || new_od != orig_od) &&
250 (bit_cfg & GPIO_BIT_CFG_TX_OE))
251 ret = thunderx_gpio_dir_out(chip, line, orig_dat ^ new_invert);
252
253 return ret;
254}
255
256static int thunderx_gpio_get(struct gpio_chip *chip, unsigned int line)
257{
258 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
259 int bank = line / 64;
260 int bank_bit = line % 64;
261 u64 read_bits = readq(txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_RX_DAT);
262 u64 masked_bits = read_bits & BIT_ULL(bank_bit);
263
264 if (test_bit(line, txgpio->invert_mask))
265 return masked_bits == 0;
266 else
267 return masked_bits != 0;
268}
269
270static void thunderx_gpio_set_multiple(struct gpio_chip *chip,
271 unsigned long *mask,
272 unsigned long *bits)
273{
274 int bank;
275 u64 set_bits, clear_bits;
276 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
277
278 for (bank = 0; bank <= chip->ngpio / 64; bank++) {
279 set_bits = bits[bank] & mask[bank];
280 clear_bits = ~bits[bank] & mask[bank];
281 writeq(set_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET);
282 writeq(clear_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_CLR);
283 }
284}
285
286static void thunderx_gpio_irq_ack(struct irq_data *data)
287{
288 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
289
290 writeq(GPIO_INTR_INTR,
291 txline->txgpio->register_base + intr_reg(txline->line));
292}
293
294static void thunderx_gpio_irq_mask(struct irq_data *data)
295{
296 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
297
298 writeq(GPIO_INTR_ENA_W1C,
299 txline->txgpio->register_base + intr_reg(txline->line));
300}
301
302static void thunderx_gpio_irq_mask_ack(struct irq_data *data)
303{
304 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
305
306 writeq(GPIO_INTR_ENA_W1C | GPIO_INTR_INTR,
307 txline->txgpio->register_base + intr_reg(txline->line));
308}
309
310static void thunderx_gpio_irq_unmask(struct irq_data *data)
311{
312 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
313
314 writeq(GPIO_INTR_ENA_W1S,
315 txline->txgpio->register_base + intr_reg(txline->line));
316}
317
318static int thunderx_gpio_irq_set_type(struct irq_data *data,
319 unsigned int flow_type)
320{
321 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
322 struct thunderx_gpio *txgpio = txline->txgpio;
323 u64 bit_cfg;
324
325 irqd_set_trigger_type(data, flow_type);
326
327 bit_cfg = txline->fil_bits | GPIO_BIT_CFG_INT_EN;
328
329 if (flow_type & IRQ_TYPE_EDGE_BOTH) {
330 irq_set_handler_locked(data, handle_fasteoi_ack_irq);
331 bit_cfg |= GPIO_BIT_CFG_INT_TYPE;
332 } else {
333 irq_set_handler_locked(data, handle_fasteoi_mask_irq);
334 }
335
336 raw_spin_lock(&txgpio->lock);
337 if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_LEVEL_LOW)) {
338 bit_cfg |= GPIO_BIT_CFG_PIN_XOR;
339 set_bit(txline->line, txgpio->invert_mask);
340 } else {
341 clear_bit(txline->line, txgpio->invert_mask);
342 }
343 clear_bit(txline->line, txgpio->od_mask);
344 writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(txline->line));
345 raw_spin_unlock(&txgpio->lock);
346
347 return IRQ_SET_MASK_OK;
348}
349
350static void thunderx_gpio_irq_enable(struct irq_data *data)
351{
352 irq_chip_enable_parent(data);
353 thunderx_gpio_irq_unmask(data);
354}
355
356static void thunderx_gpio_irq_disable(struct irq_data *data)
357{
358 thunderx_gpio_irq_mask(data);
359 irq_chip_disable_parent(data);
360}
361
362static int thunderx_gpio_irq_request_resources(struct irq_data *data)
363{
364 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
365 struct thunderx_gpio *txgpio = txline->txgpio;
366 struct irq_data *parent_data = data->parent_data;
367 int r;
368
369 r = gpiochip_lock_as_irq(&txgpio->chip, txline->line);
370 if (r)
371 return r;
372
373 if (parent_data && parent_data->chip->irq_request_resources) {
374 r = parent_data->chip->irq_request_resources(parent_data);
375 if (r)
376 goto error;
377 }
378
379 return 0;
380error:
381 gpiochip_unlock_as_irq(&txgpio->chip, txline->line);
382 return r;
383}
384
385static void thunderx_gpio_irq_release_resources(struct irq_data *data)
386{
387 struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
388 struct thunderx_gpio *txgpio = txline->txgpio;
389 struct irq_data *parent_data = data->parent_data;
390
391 if (parent_data && parent_data->chip->irq_release_resources)
392 parent_data->chip->irq_release_resources(parent_data);
393
394 gpiochip_unlock_as_irq(&txgpio->chip, txline->line);
395}
396
397/*
398 * Interrupts are chained from underlying MSI-X vectors. We have
399 * these irq_chip functions to be able to handle level triggering
400 * semantics and other acknowledgment tasks associated with the GPIO
401 * mechanism.
402 */
403static struct irq_chip thunderx_gpio_irq_chip = {
404 .name = "GPIO",
405 .irq_enable = thunderx_gpio_irq_enable,
406 .irq_disable = thunderx_gpio_irq_disable,
407 .irq_ack = thunderx_gpio_irq_ack,
408 .irq_mask = thunderx_gpio_irq_mask,
409 .irq_mask_ack = thunderx_gpio_irq_mask_ack,
410 .irq_unmask = thunderx_gpio_irq_unmask,
411 .irq_eoi = irq_chip_eoi_parent,
412 .irq_set_affinity = irq_chip_set_affinity_parent,
413 .irq_request_resources = thunderx_gpio_irq_request_resources,
414 .irq_release_resources = thunderx_gpio_irq_release_resources,
415 .irq_set_type = thunderx_gpio_irq_set_type,
416
417 .flags = IRQCHIP_SET_TYPE_MASKED
418};
419
420static int thunderx_gpio_irq_translate(struct irq_domain *d,
421 struct irq_fwspec *fwspec,
422 irq_hw_number_t *hwirq,
423 unsigned int *type)
424{
425 struct thunderx_gpio *txgpio = d->host_data;
426
427 if (WARN_ON(fwspec->param_count < 2))
428 return -EINVAL;
429 if (fwspec->param[0] >= txgpio->chip.ngpio)
430 return -EINVAL;
431 *hwirq = fwspec->param[0];
432 *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
433 return 0;
434}
435
436static int thunderx_gpio_irq_alloc(struct irq_domain *d, unsigned int virq,
437 unsigned int nr_irqs, void *arg)
438{
439 struct thunderx_line *txline = arg;
440
441 return irq_domain_set_hwirq_and_chip(d, virq, txline->line,
442 &thunderx_gpio_irq_chip, txline);
443}
444
445static const struct irq_domain_ops thunderx_gpio_irqd_ops = {
446 .alloc = thunderx_gpio_irq_alloc,
447 .translate = thunderx_gpio_irq_translate
448};
449
450static int thunderx_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
451{
452 struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
453
454 return irq_find_mapping(txgpio->irqd, offset);
455}
456
457static int thunderx_gpio_probe(struct pci_dev *pdev,
458 const struct pci_device_id *id)
459{
460 void __iomem * const *tbl;
461 struct device *dev = &pdev->dev;
462 struct thunderx_gpio *txgpio;
463 struct gpio_chip *chip;
464 int ngpio, i;
465 int err = 0;
466
467 txgpio = devm_kzalloc(dev, sizeof(*txgpio), GFP_KERNEL);
468 if (!txgpio)
469 return -ENOMEM;
470
471 raw_spin_lock_init(&txgpio->lock);
472 chip = &txgpio->chip;
473
474 pci_set_drvdata(pdev, txgpio);
475
476 err = pcim_enable_device(pdev);
477 if (err) {
478 dev_err(dev, "Failed to enable PCI device: err %d\n", err);
479 goto out;
480 }
481
482 err = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
483 if (err) {
484 dev_err(dev, "Failed to iomap PCI device: err %d\n", err);
485 goto out;
486 }
487
488 tbl = pcim_iomap_table(pdev);
489 txgpio->register_base = tbl[0];
490 if (!txgpio->register_base) {
491 dev_err(dev, "Cannot map PCI resource\n");
492 err = -ENOMEM;
493 goto out;
494 }
495
496 if (pdev->subsystem_device == 0xa10a) {
497 /* CN88XX has no GPIO_CONST register*/
498 ngpio = 50;
499 txgpio->base_msi = 48;
500 } else {
501 u64 c = readq(txgpio->register_base + GPIO_CONST);
502
503 ngpio = c & GPIO_CONST_GPIOS_MASK;
504 txgpio->base_msi = (c >> 8) & 0xff;
505 }
506
507 txgpio->msix_entries = devm_kcalloc(dev,
508 ngpio, sizeof(struct msix_entry),
509 GFP_KERNEL);
510 if (!txgpio->msix_entries) {
511 err = -ENOMEM;
512 goto out;
513 }
514
515 txgpio->line_entries = devm_kcalloc(dev,
516 ngpio,
517 sizeof(struct thunderx_line),
518 GFP_KERNEL);
519 if (!txgpio->line_entries) {
520 err = -ENOMEM;
521 goto out;
522 }
523
524 for (i = 0; i < ngpio; i++) {
525 u64 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(i));
526
527 txgpio->msix_entries[i].entry = txgpio->base_msi + (2 * i);
528 txgpio->line_entries[i].line = i;
529 txgpio->line_entries[i].txgpio = txgpio;
530 /*
531 * If something has already programmed the pin, use
532 * the existing glitch filter settings, otherwise go
533 * to 400nS.
534 */
535 txgpio->line_entries[i].fil_bits = bit_cfg ?
536 (bit_cfg & GPIO_BIT_CFG_FIL_MASK) : GLITCH_FILTER_400NS;
537
538 if ((bit_cfg & GPIO_BIT_CFG_TX_OE) && (bit_cfg & GPIO_BIT_CFG_TX_OD))
539 set_bit(i, txgpio->od_mask);
540 if (bit_cfg & GPIO_BIT_CFG_PIN_XOR)
541 set_bit(i, txgpio->invert_mask);
542 }
543
544
545 /* Enable all MSI-X for interrupts on all possible lines. */
546 err = pci_enable_msix_range(pdev, txgpio->msix_entries, ngpio, ngpio);
547 if (err < 0)
548 goto out;
549
550 /*
551 * Push GPIO specific irqdomain on hierarchy created as a side
552 * effect of the pci_enable_msix()
553 */
554 txgpio->irqd = irq_domain_create_hierarchy(irq_get_irq_data(txgpio->msix_entries[0].vector)->domain,
555 0, 0, of_node_to_fwnode(dev->of_node),
556 &thunderx_gpio_irqd_ops, txgpio);
557 if (!txgpio->irqd) {
558 err = -ENOMEM;
559 goto out;
560 }
561
562 /* Push on irq_data and the domain for each line. */
563 for (i = 0; i < ngpio; i++) {
564 err = irq_domain_push_irq(txgpio->irqd,
565 txgpio->msix_entries[i].vector,
566 &txgpio->line_entries[i]);
567 if (err < 0)
568 dev_err(dev, "irq_domain_push_irq: %d\n", err);
569 }
570
571 chip->label = KBUILD_MODNAME;
572 chip->parent = dev;
573 chip->owner = THIS_MODULE;
574 chip->request = thunderx_gpio_request;
575 chip->base = -1; /* System allocated */
576 chip->can_sleep = false;
577 chip->ngpio = ngpio;
578 chip->get_direction = thunderx_gpio_get_direction;
579 chip->direction_input = thunderx_gpio_dir_in;
580 chip->get = thunderx_gpio_get;
581 chip->direction_output = thunderx_gpio_dir_out;
582 chip->set = thunderx_gpio_set;
583 chip->set_multiple = thunderx_gpio_set_multiple;
584 chip->set_config = thunderx_gpio_set_config;
585 chip->to_irq = thunderx_gpio_to_irq;
586 err = devm_gpiochip_add_data(dev, chip, txgpio);
587 if (err)
588 goto out;
589
590 dev_info(dev, "ThunderX GPIO: %d lines with base %d.\n",
591 ngpio, chip->base);
592 return 0;
593out:
594 pci_set_drvdata(pdev, NULL);
595 return err;
596}
597
598static void thunderx_gpio_remove(struct pci_dev *pdev)
599{
600 int i;
601 struct thunderx_gpio *txgpio = pci_get_drvdata(pdev);
602
603 for (i = 0; i < txgpio->chip.ngpio; i++)
604 irq_domain_pop_irq(txgpio->irqd,
605 txgpio->msix_entries[i].vector);
606
607 irq_domain_remove(txgpio->irqd);
608
609 pci_set_drvdata(pdev, NULL);
610}
611
612static const struct pci_device_id thunderx_gpio_id_table[] = {
613 { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xA00A) },
614 { 0, } /* end of table */
615};
616
617MODULE_DEVICE_TABLE(pci, thunderx_gpio_id_table);
618
619static struct pci_driver thunderx_gpio_driver = {
620 .name = KBUILD_MODNAME,
621 .id_table = thunderx_gpio_id_table,
622 .probe = thunderx_gpio_probe,
623 .remove = thunderx_gpio_remove,
624};
625
626module_pci_driver(thunderx_gpio_driver);
627
628MODULE_DESCRIPTION("Cavium Inc. ThunderX/OCTEON-TX GPIO Driver");
629MODULE_LICENSE("GPL");
630