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v6.13.7
  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/property.h>
 18#include <linux/spinlock.h>
 
 
 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 msix_entry	*msix_entries;	/* per line MSI-X */
 57	struct thunderx_line	*line_entries;	/* per line irq info */
 58	raw_spinlock_t		lock;
 59	unsigned long		invert_mask[2];
 60	unsigned long		od_mask[2];
 61	int			base_msi;
 62};
 63
 64static unsigned int bit_cfg_reg(unsigned int line)
 65{
 66	return 8 * line + GPIO_BIT_CFG;
 67}
 68
 69static unsigned int intr_reg(unsigned int line)
 70{
 71	return 8 * line + GPIO_INTR;
 72}
 73
 74static bool thunderx_gpio_is_gpio_nowarn(struct thunderx_gpio *txgpio,
 75					 unsigned int line)
 76{
 77	u64 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
 78
 79	return (bit_cfg & GPIO_BIT_CFG_PIN_SEL_MASK) == 0;
 80}
 81
 82/*
 83 * Check (and WARN) that the pin is available for GPIO.  We will not
 84 * allow modification of the state of non-GPIO pins from this driver.
 85 */
 86static bool thunderx_gpio_is_gpio(struct thunderx_gpio *txgpio,
 87				  unsigned int line)
 88{
 89	bool rv = thunderx_gpio_is_gpio_nowarn(txgpio, line);
 90
 91	WARN_RATELIMIT(!rv, "Pin %d not available for GPIO\n", line);
 92
 93	return rv;
 94}
 95
 96static int thunderx_gpio_request(struct gpio_chip *chip, unsigned int line)
 97{
 98	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
 99
100	return thunderx_gpio_is_gpio(txgpio, line) ? 0 : -EIO;
101}
102
103static int thunderx_gpio_dir_in(struct gpio_chip *chip, unsigned int line)
104{
105	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
106
107	if (!thunderx_gpio_is_gpio(txgpio, line))
108		return -EIO;
109
110	raw_spin_lock(&txgpio->lock);
111	clear_bit(line, txgpio->invert_mask);
112	clear_bit(line, txgpio->od_mask);
113	writeq(txgpio->line_entries[line].fil_bits,
114	       txgpio->register_base + bit_cfg_reg(line));
115	raw_spin_unlock(&txgpio->lock);
116	return 0;
117}
118
119static void thunderx_gpio_set(struct gpio_chip *chip, unsigned int line,
120			      int value)
121{
122	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
123	int bank = line / 64;
124	int bank_bit = line % 64;
125
126	void __iomem *reg = txgpio->register_base +
127		(bank * GPIO_2ND_BANK) + (value ? GPIO_TX_SET : GPIO_TX_CLR);
128
129	writeq(BIT_ULL(bank_bit), reg);
130}
131
132static int thunderx_gpio_dir_out(struct gpio_chip *chip, unsigned int line,
133				 int value)
134{
135	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
136	u64 bit_cfg = txgpio->line_entries[line].fil_bits | GPIO_BIT_CFG_TX_OE;
137
138	if (!thunderx_gpio_is_gpio(txgpio, line))
139		return -EIO;
140
141	raw_spin_lock(&txgpio->lock);
142
143	thunderx_gpio_set(chip, line, value);
144
145	if (test_bit(line, txgpio->invert_mask))
146		bit_cfg |= GPIO_BIT_CFG_PIN_XOR;
147
148	if (test_bit(line, txgpio->od_mask))
149		bit_cfg |= GPIO_BIT_CFG_TX_OD;
150
151	writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(line));
152
153	raw_spin_unlock(&txgpio->lock);
154	return 0;
155}
156
157static int thunderx_gpio_get_direction(struct gpio_chip *chip, unsigned int line)
158{
159	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
160	u64 bit_cfg;
161
162	if (!thunderx_gpio_is_gpio_nowarn(txgpio, line))
163		/*
164		 * Say it is input for now to avoid WARNing on
165		 * gpiochip_add_data().  We will WARN if someone
166		 * requests it or tries to use it.
167		 */
168		return 1;
169
170	bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
171
172	if (bit_cfg & GPIO_BIT_CFG_TX_OE)
173		return GPIO_LINE_DIRECTION_OUT;
174
175	return GPIO_LINE_DIRECTION_IN;
176}
177
178static int thunderx_gpio_set_config(struct gpio_chip *chip,
179				    unsigned int line,
180				    unsigned long cfg)
181{
182	bool orig_invert, orig_od, orig_dat, new_invert, new_od;
183	u32 arg, sel;
184	u64 bit_cfg;
185	int bank = line / 64;
186	int bank_bit = line % 64;
187	int ret = -ENOTSUPP;
188	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
189	void __iomem *reg = txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET;
190
191	if (!thunderx_gpio_is_gpio(txgpio, line))
192		return -EIO;
193
194	raw_spin_lock(&txgpio->lock);
195	orig_invert = test_bit(line, txgpio->invert_mask);
196	new_invert  = orig_invert;
197	orig_od = test_bit(line, txgpio->od_mask);
198	new_od = orig_od;
199	orig_dat = ((readq(reg) >> bank_bit) & 1) ^ orig_invert;
200	bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
201	switch (pinconf_to_config_param(cfg)) {
202	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
203		/*
204		 * Weird, setting open-drain mode causes signal
205		 * inversion.  Note this so we can compensate in the
206		 * dir_out function.
207		 */
208		set_bit(line, txgpio->invert_mask);
209		new_invert  = true;
210		set_bit(line, txgpio->od_mask);
211		new_od = true;
212		ret = 0;
213		break;
214	case PIN_CONFIG_DRIVE_PUSH_PULL:
215		clear_bit(line, txgpio->invert_mask);
216		new_invert  = false;
217		clear_bit(line, txgpio->od_mask);
218		new_od  = false;
219		ret = 0;
220		break;
221	case PIN_CONFIG_INPUT_DEBOUNCE:
222		arg = pinconf_to_config_argument(cfg);
223		if (arg > 1228) { /* 15 * 2^15 * 2.5nS maximum */
224			ret = -EINVAL;
225			break;
226		}
227		arg *= 400; /* scale to 2.5nS clocks. */
228		sel = 0;
229		while (arg > 15) {
230			sel++;
231			arg++; /* always round up */
232			arg >>= 1;
233		}
234		txgpio->line_entries[line].fil_bits =
235			(sel << GPIO_BIT_CFG_FIL_SEL_SHIFT) |
236			(arg << GPIO_BIT_CFG_FIL_CNT_SHIFT);
237		bit_cfg &= ~GPIO_BIT_CFG_FIL_MASK;
238		bit_cfg |= txgpio->line_entries[line].fil_bits;
239		writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(line));
240		ret = 0;
241		break;
242	default:
243		break;
244	}
245	raw_spin_unlock(&txgpio->lock);
246
247	/*
248	 * If currently output and OPEN_DRAIN changed, install the new
249	 * settings
250	 */
251	if ((new_invert != orig_invert || new_od != orig_od) &&
252	    (bit_cfg & GPIO_BIT_CFG_TX_OE))
253		ret = thunderx_gpio_dir_out(chip, line, orig_dat ^ new_invert);
254
255	return ret;
256}
257
258static int thunderx_gpio_get(struct gpio_chip *chip, unsigned int line)
259{
260	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
261	int bank = line / 64;
262	int bank_bit = line % 64;
263	u64 read_bits = readq(txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_RX_DAT);
264	u64 masked_bits = read_bits & BIT_ULL(bank_bit);
265
266	if (test_bit(line, txgpio->invert_mask))
267		return masked_bits == 0;
268	else
269		return masked_bits != 0;
270}
271
272static void thunderx_gpio_set_multiple(struct gpio_chip *chip,
273				       unsigned long *mask,
274				       unsigned long *bits)
275{
276	int bank;
277	u64 set_bits, clear_bits;
278	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
279
280	for (bank = 0; bank <= chip->ngpio / 64; bank++) {
281		set_bits = bits[bank] & mask[bank];
282		clear_bits = ~bits[bank] & mask[bank];
283		writeq(set_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET);
284		writeq(clear_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_CLR);
285	}
286}
287
288static void thunderx_gpio_irq_ack(struct irq_data *d)
289{
290	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
291	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
292
293	writeq(GPIO_INTR_INTR,
294	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
295}
296
297static void thunderx_gpio_irq_mask(struct irq_data *d)
298{
299	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
300	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
301
302	writeq(GPIO_INTR_ENA_W1C,
303	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
304}
305
306static void thunderx_gpio_irq_mask_ack(struct irq_data *d)
307{
308	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
309	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
310
311	writeq(GPIO_INTR_ENA_W1C | GPIO_INTR_INTR,
312	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
313}
314
315static void thunderx_gpio_irq_unmask(struct irq_data *d)
316{
317	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
318	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
319
320	writeq(GPIO_INTR_ENA_W1S,
321	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
322}
323
324static int thunderx_gpio_irq_set_type(struct irq_data *d,
325				      unsigned int flow_type)
326{
327	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
328	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
329	struct thunderx_line *txline =
330		&txgpio->line_entries[irqd_to_hwirq(d)];
331	u64 bit_cfg;
332
333	irqd_set_trigger_type(d, flow_type);
334
335	bit_cfg = txline->fil_bits | GPIO_BIT_CFG_INT_EN;
336
337	if (flow_type & IRQ_TYPE_EDGE_BOTH) {
338		irq_set_handler_locked(d, handle_fasteoi_ack_irq);
339		bit_cfg |= GPIO_BIT_CFG_INT_TYPE;
340	} else {
341		irq_set_handler_locked(d, handle_fasteoi_mask_irq);
342	}
343
344	raw_spin_lock(&txgpio->lock);
345	if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_LEVEL_LOW)) {
346		bit_cfg |= GPIO_BIT_CFG_PIN_XOR;
347		set_bit(txline->line, txgpio->invert_mask);
348	} else {
349		clear_bit(txline->line, txgpio->invert_mask);
350	}
351	clear_bit(txline->line, txgpio->od_mask);
352	writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(txline->line));
353	raw_spin_unlock(&txgpio->lock);
354
355	return IRQ_SET_MASK_OK;
356}
357
358static void thunderx_gpio_irq_enable(struct irq_data *d)
359{
360	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
361
362	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
363	irq_chip_enable_parent(d);
364	thunderx_gpio_irq_unmask(d);
365}
366
367static void thunderx_gpio_irq_disable(struct irq_data *d)
368{
369	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
370
371	thunderx_gpio_irq_mask(d);
372	irq_chip_disable_parent(d);
373	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
374}
375
376/*
377 * Interrupts are chained from underlying MSI-X vectors.  We have
378 * these irq_chip functions to be able to handle level triggering
379 * semantics and other acknowledgment tasks associated with the GPIO
380 * mechanism.
381 */
382static const struct irq_chip thunderx_gpio_irq_chip = {
383	.name			= "GPIO",
384	.irq_enable		= thunderx_gpio_irq_enable,
385	.irq_disable		= thunderx_gpio_irq_disable,
386	.irq_ack		= thunderx_gpio_irq_ack,
387	.irq_mask		= thunderx_gpio_irq_mask,
388	.irq_mask_ack		= thunderx_gpio_irq_mask_ack,
389	.irq_unmask		= thunderx_gpio_irq_unmask,
390	.irq_eoi		= irq_chip_eoi_parent,
391	.irq_set_affinity	= irq_chip_set_affinity_parent,
392	.irq_set_type		= thunderx_gpio_irq_set_type,
393	.flags			= IRQCHIP_SET_TYPE_MASKED | IRQCHIP_IMMUTABLE,
394	GPIOCHIP_IRQ_RESOURCE_HELPERS,
395};
396
397static int thunderx_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
398					       unsigned int child,
399					       unsigned int child_type,
400					       unsigned int *parent,
401					       unsigned int *parent_type)
402{
403	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
404	struct irq_data *irqd;
405	unsigned int irq;
406
407	irq = txgpio->msix_entries[child].vector;
408	irqd = irq_domain_get_irq_data(gc->irq.parent_domain, irq);
409	if (!irqd)
410		return -EINVAL;
411	*parent = irqd_to_hwirq(irqd);
412	*parent_type = IRQ_TYPE_LEVEL_HIGH;
413	return 0;
414}
415
416static int thunderx_gpio_populate_parent_alloc_info(struct gpio_chip *chip,
417						    union gpio_irq_fwspec *gfwspec,
418						    unsigned int parent_hwirq,
419						    unsigned int parent_type)
420{
421	msi_alloc_info_t *info = &gfwspec->msiinfo;
 
 
 
422
423	info->hwirq = parent_hwirq;
424	return 0;
425}
426
427static int thunderx_gpio_probe(struct pci_dev *pdev,
428			       const struct pci_device_id *id)
429{
430	void __iomem * const *tbl;
431	struct device *dev = &pdev->dev;
432	struct thunderx_gpio *txgpio;
433	struct gpio_chip *chip;
434	struct gpio_irq_chip *girq;
435	int ngpio, i;
436	int err = 0;
437
438	txgpio = devm_kzalloc(dev, sizeof(*txgpio), GFP_KERNEL);
439	if (!txgpio)
440		return -ENOMEM;
441
442	raw_spin_lock_init(&txgpio->lock);
443	chip = &txgpio->chip;
444
445	pci_set_drvdata(pdev, txgpio);
446
447	err = pcim_enable_device(pdev);
448	if (err) {
449		dev_err(dev, "Failed to enable PCI device: err %d\n", err);
450		goto out;
451	}
452
453	err = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
454	if (err) {
455		dev_err(dev, "Failed to iomap PCI device: err %d\n", err);
456		goto out;
457	}
458
459	tbl = pcim_iomap_table(pdev);
460	txgpio->register_base = tbl[0];
461	if (!txgpio->register_base) {
462		dev_err(dev, "Cannot map PCI resource\n");
463		err = -ENOMEM;
464		goto out;
465	}
466
467	if (pdev->subsystem_device == 0xa10a) {
468		/* CN88XX has no GPIO_CONST register*/
469		ngpio = 50;
470		txgpio->base_msi = 48;
471	} else {
472		u64 c = readq(txgpio->register_base + GPIO_CONST);
473
474		ngpio = c & GPIO_CONST_GPIOS_MASK;
475		txgpio->base_msi = (c >> 8) & 0xff;
476	}
477
478	txgpio->msix_entries = devm_kcalloc(dev,
479					    ngpio, sizeof(struct msix_entry),
480					    GFP_KERNEL);
481	if (!txgpio->msix_entries) {
482		err = -ENOMEM;
483		goto out;
484	}
485
486	txgpio->line_entries = devm_kcalloc(dev,
487					    ngpio,
488					    sizeof(struct thunderx_line),
489					    GFP_KERNEL);
490	if (!txgpio->line_entries) {
491		err = -ENOMEM;
492		goto out;
493	}
494
495	for (i = 0; i < ngpio; i++) {
496		u64 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(i));
497
498		txgpio->msix_entries[i].entry = txgpio->base_msi + (2 * i);
499		txgpio->line_entries[i].line = i;
500		txgpio->line_entries[i].txgpio = txgpio;
501		/*
502		 * If something has already programmed the pin, use
503		 * the existing glitch filter settings, otherwise go
504		 * to 400nS.
505		 */
506		txgpio->line_entries[i].fil_bits = bit_cfg ?
507			(bit_cfg & GPIO_BIT_CFG_FIL_MASK) : GLITCH_FILTER_400NS;
508
509		if ((bit_cfg & GPIO_BIT_CFG_TX_OE) && (bit_cfg & GPIO_BIT_CFG_TX_OD))
510			set_bit(i, txgpio->od_mask);
511		if (bit_cfg & GPIO_BIT_CFG_PIN_XOR)
512			set_bit(i, txgpio->invert_mask);
513	}
514
515
516	/* Enable all MSI-X for interrupts on all possible lines. */
517	err = pci_enable_msix_range(pdev, txgpio->msix_entries, ngpio, ngpio);
518	if (err < 0)
519		goto out;
520
521	chip->label = KBUILD_MODNAME;
522	chip->parent = dev;
523	chip->owner = THIS_MODULE;
524	chip->request = thunderx_gpio_request;
525	chip->base = -1; /* System allocated */
526	chip->can_sleep = false;
527	chip->ngpio = ngpio;
528	chip->get_direction = thunderx_gpio_get_direction;
529	chip->direction_input = thunderx_gpio_dir_in;
530	chip->get = thunderx_gpio_get;
531	chip->direction_output = thunderx_gpio_dir_out;
532	chip->set = thunderx_gpio_set;
533	chip->set_multiple = thunderx_gpio_set_multiple;
534	chip->set_config = thunderx_gpio_set_config;
535	girq = &chip->irq;
536	gpio_irq_chip_set_chip(girq, &thunderx_gpio_irq_chip);
537	girq->fwnode = dev_fwnode(dev);
538	girq->parent_domain =
539		irq_get_irq_data(txgpio->msix_entries[0].vector)->domain;
540	girq->child_to_parent_hwirq = thunderx_gpio_child_to_parent_hwirq;
541	girq->populate_parent_alloc_arg = thunderx_gpio_populate_parent_alloc_info;
542	girq->handler = handle_bad_irq;
543	girq->default_type = IRQ_TYPE_NONE;
544
545	err = devm_gpiochip_add_data(dev, chip, txgpio);
546	if (err)
547		goto out;
548
549	/* Push on irq_data and the domain for each line. */
550	for (i = 0; i < ngpio; i++) {
551		struct irq_fwspec fwspec;
552
553		fwspec.fwnode = dev_fwnode(dev);
554		fwspec.param_count = 2;
555		fwspec.param[0] = i;
556		fwspec.param[1] = IRQ_TYPE_NONE;
557		err = irq_domain_push_irq(girq->domain,
558					  txgpio->msix_entries[i].vector,
559					  &fwspec);
560		if (err < 0)
561			dev_err(dev, "irq_domain_push_irq: %d\n", err);
562	}
563
564	dev_info(dev, "ThunderX GPIO: %d lines with base %d.\n",
565		 ngpio, chip->base);
566	return 0;
567out:
568	pci_set_drvdata(pdev, NULL);
569	return err;
570}
571
572static void thunderx_gpio_remove(struct pci_dev *pdev)
573{
574	int i;
575	struct thunderx_gpio *txgpio = pci_get_drvdata(pdev);
576
577	for (i = 0; i < txgpio->chip.ngpio; i++)
578		irq_domain_pop_irq(txgpio->chip.irq.domain,
579				   txgpio->msix_entries[i].vector);
580
581	irq_domain_remove(txgpio->chip.irq.domain);
582
583	pci_set_drvdata(pdev, NULL);
584}
585
586static const struct pci_device_id thunderx_gpio_id_table[] = {
587	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xA00A) },
588	{ 0, }	/* end of table */
589};
590
591MODULE_DEVICE_TABLE(pci, thunderx_gpio_id_table);
592
593static struct pci_driver thunderx_gpio_driver = {
594	.name = KBUILD_MODNAME,
595	.id_table = thunderx_gpio_id_table,
596	.probe = thunderx_gpio_probe,
597	.remove = thunderx_gpio_remove,
598};
599
600module_pci_driver(thunderx_gpio_driver);
601
602MODULE_DESCRIPTION("Cavium Inc. ThunderX/OCTEON-TX GPIO Driver");
603MODULE_LICENSE("GPL");
v5.9
  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#include <asm-generic/msi.h>
 19
 20
 21#define GPIO_RX_DAT	0x0
 22#define GPIO_TX_SET	0x8
 23#define GPIO_TX_CLR	0x10
 24#define GPIO_CONST	0x90
 25#define  GPIO_CONST_GPIOS_MASK 0xff
 26#define GPIO_BIT_CFG	0x400
 27#define  GPIO_BIT_CFG_TX_OE		BIT(0)
 28#define  GPIO_BIT_CFG_PIN_XOR		BIT(1)
 29#define  GPIO_BIT_CFG_INT_EN		BIT(2)
 30#define  GPIO_BIT_CFG_INT_TYPE		BIT(3)
 31#define  GPIO_BIT_CFG_FIL_MASK		GENMASK(11, 4)
 32#define  GPIO_BIT_CFG_FIL_CNT_SHIFT	4
 33#define  GPIO_BIT_CFG_FIL_SEL_SHIFT	8
 34#define  GPIO_BIT_CFG_TX_OD		BIT(12)
 35#define  GPIO_BIT_CFG_PIN_SEL_MASK	GENMASK(25, 16)
 36#define GPIO_INTR	0x800
 37#define  GPIO_INTR_INTR			BIT(0)
 38#define  GPIO_INTR_INTR_W1S		BIT(1)
 39#define  GPIO_INTR_ENA_W1C		BIT(2)
 40#define  GPIO_INTR_ENA_W1S		BIT(3)
 41#define GPIO_2ND_BANK	0x1400
 42
 43#define GLITCH_FILTER_400NS ((4u << GPIO_BIT_CFG_FIL_SEL_SHIFT) | \
 44			     (9u << GPIO_BIT_CFG_FIL_CNT_SHIFT))
 45
 46struct thunderx_gpio;
 47
 48struct thunderx_line {
 49	struct thunderx_gpio	*txgpio;
 50	unsigned int		line;
 51	unsigned int		fil_bits;
 52};
 53
 54struct thunderx_gpio {
 55	struct gpio_chip	chip;
 56	u8 __iomem		*register_base;
 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	if (bit_cfg & GPIO_BIT_CFG_TX_OE)
174		return GPIO_LINE_DIRECTION_OUT;
175
176	return GPIO_LINE_DIRECTION_IN;
177}
178
179static int thunderx_gpio_set_config(struct gpio_chip *chip,
180				    unsigned int line,
181				    unsigned long cfg)
182{
183	bool orig_invert, orig_od, orig_dat, new_invert, new_od;
184	u32 arg, sel;
185	u64 bit_cfg;
186	int bank = line / 64;
187	int bank_bit = line % 64;
188	int ret = -ENOTSUPP;
189	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
190	void __iomem *reg = txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET;
191
192	if (!thunderx_gpio_is_gpio(txgpio, line))
193		return -EIO;
194
195	raw_spin_lock(&txgpio->lock);
196	orig_invert = test_bit(line, txgpio->invert_mask);
197	new_invert  = orig_invert;
198	orig_od = test_bit(line, txgpio->od_mask);
199	new_od = orig_od;
200	orig_dat = ((readq(reg) >> bank_bit) & 1) ^ orig_invert;
201	bit_cfg = readq(txgpio->register_base + bit_cfg_reg(line));
202	switch (pinconf_to_config_param(cfg)) {
203	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
204		/*
205		 * Weird, setting open-drain mode causes signal
206		 * inversion.  Note this so we can compensate in the
207		 * dir_out function.
208		 */
209		set_bit(line, txgpio->invert_mask);
210		new_invert  = true;
211		set_bit(line, txgpio->od_mask);
212		new_od = true;
213		ret = 0;
214		break;
215	case PIN_CONFIG_DRIVE_PUSH_PULL:
216		clear_bit(line, txgpio->invert_mask);
217		new_invert  = false;
218		clear_bit(line, txgpio->od_mask);
219		new_od  = false;
220		ret = 0;
221		break;
222	case PIN_CONFIG_INPUT_DEBOUNCE:
223		arg = pinconf_to_config_argument(cfg);
224		if (arg > 1228) { /* 15 * 2^15 * 2.5nS maximum */
225			ret = -EINVAL;
226			break;
227		}
228		arg *= 400; /* scale to 2.5nS clocks. */
229		sel = 0;
230		while (arg > 15) {
231			sel++;
232			arg++; /* always round up */
233			arg >>= 1;
234		}
235		txgpio->line_entries[line].fil_bits =
236			(sel << GPIO_BIT_CFG_FIL_SEL_SHIFT) |
237			(arg << GPIO_BIT_CFG_FIL_CNT_SHIFT);
238		bit_cfg &= ~GPIO_BIT_CFG_FIL_MASK;
239		bit_cfg |= txgpio->line_entries[line].fil_bits;
240		writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(line));
241		ret = 0;
242		break;
243	default:
244		break;
245	}
246	raw_spin_unlock(&txgpio->lock);
247
248	/*
249	 * If currently output and OPEN_DRAIN changed, install the new
250	 * settings
251	 */
252	if ((new_invert != orig_invert || new_od != orig_od) &&
253	    (bit_cfg & GPIO_BIT_CFG_TX_OE))
254		ret = thunderx_gpio_dir_out(chip, line, orig_dat ^ new_invert);
255
256	return ret;
257}
258
259static int thunderx_gpio_get(struct gpio_chip *chip, unsigned int line)
260{
261	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
262	int bank = line / 64;
263	int bank_bit = line % 64;
264	u64 read_bits = readq(txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_RX_DAT);
265	u64 masked_bits = read_bits & BIT_ULL(bank_bit);
266
267	if (test_bit(line, txgpio->invert_mask))
268		return masked_bits == 0;
269	else
270		return masked_bits != 0;
271}
272
273static void thunderx_gpio_set_multiple(struct gpio_chip *chip,
274				       unsigned long *mask,
275				       unsigned long *bits)
276{
277	int bank;
278	u64 set_bits, clear_bits;
279	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
280
281	for (bank = 0; bank <= chip->ngpio / 64; bank++) {
282		set_bits = bits[bank] & mask[bank];
283		clear_bits = ~bits[bank] & mask[bank];
284		writeq(set_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET);
285		writeq(clear_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_CLR);
286	}
287}
288
289static void thunderx_gpio_irq_ack(struct irq_data *d)
290{
291	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
292	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
293
294	writeq(GPIO_INTR_INTR,
295	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
296}
297
298static void thunderx_gpio_irq_mask(struct irq_data *d)
299{
300	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
301	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
302
303	writeq(GPIO_INTR_ENA_W1C,
304	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
305}
306
307static void thunderx_gpio_irq_mask_ack(struct irq_data *d)
308{
309	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
310	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
311
312	writeq(GPIO_INTR_ENA_W1C | GPIO_INTR_INTR,
313	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
314}
315
316static void thunderx_gpio_irq_unmask(struct irq_data *d)
317{
318	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
319	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
320
321	writeq(GPIO_INTR_ENA_W1S,
322	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
323}
324
325static int thunderx_gpio_irq_set_type(struct irq_data *d,
326				      unsigned int flow_type)
327{
328	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
329	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
330	struct thunderx_line *txline =
331		&txgpio->line_entries[irqd_to_hwirq(d)];
332	u64 bit_cfg;
333
334	irqd_set_trigger_type(d, flow_type);
335
336	bit_cfg = txline->fil_bits | GPIO_BIT_CFG_INT_EN;
337
338	if (flow_type & IRQ_TYPE_EDGE_BOTH) {
339		irq_set_handler_locked(d, handle_fasteoi_ack_irq);
340		bit_cfg |= GPIO_BIT_CFG_INT_TYPE;
341	} else {
342		irq_set_handler_locked(d, handle_fasteoi_mask_irq);
343	}
344
345	raw_spin_lock(&txgpio->lock);
346	if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_LEVEL_LOW)) {
347		bit_cfg |= GPIO_BIT_CFG_PIN_XOR;
348		set_bit(txline->line, txgpio->invert_mask);
349	} else {
350		clear_bit(txline->line, txgpio->invert_mask);
351	}
352	clear_bit(txline->line, txgpio->od_mask);
353	writeq(bit_cfg, txgpio->register_base + bit_cfg_reg(txline->line));
354	raw_spin_unlock(&txgpio->lock);
355
356	return IRQ_SET_MASK_OK;
357}
358
359static void thunderx_gpio_irq_enable(struct irq_data *data)
360{
361	irq_chip_enable_parent(data);
362	thunderx_gpio_irq_unmask(data);
 
 
 
363}
364
365static void thunderx_gpio_irq_disable(struct irq_data *data)
366{
367	thunderx_gpio_irq_mask(data);
368	irq_chip_disable_parent(data);
 
 
 
369}
370
371/*
372 * Interrupts are chained from underlying MSI-X vectors.  We have
373 * these irq_chip functions to be able to handle level triggering
374 * semantics and other acknowledgment tasks associated with the GPIO
375 * mechanism.
376 */
377static struct irq_chip thunderx_gpio_irq_chip = {
378	.name			= "GPIO",
379	.irq_enable		= thunderx_gpio_irq_enable,
380	.irq_disable		= thunderx_gpio_irq_disable,
381	.irq_ack		= thunderx_gpio_irq_ack,
382	.irq_mask		= thunderx_gpio_irq_mask,
383	.irq_mask_ack		= thunderx_gpio_irq_mask_ack,
384	.irq_unmask		= thunderx_gpio_irq_unmask,
385	.irq_eoi		= irq_chip_eoi_parent,
386	.irq_set_affinity	= irq_chip_set_affinity_parent,
387	.irq_set_type		= thunderx_gpio_irq_set_type,
388
389	.flags			= IRQCHIP_SET_TYPE_MASKED
390};
391
392static int thunderx_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
393					       unsigned int child,
394					       unsigned int child_type,
395					       unsigned int *parent,
396					       unsigned int *parent_type)
397{
398	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
399	struct irq_data *irqd;
400	unsigned int irq;
401
402	irq = txgpio->msix_entries[child].vector;
403	irqd = irq_domain_get_irq_data(gc->irq.parent_domain, irq);
404	if (!irqd)
405		return -EINVAL;
406	*parent = irqd_to_hwirq(irqd);
407	*parent_type = IRQ_TYPE_LEVEL_HIGH;
408	return 0;
409}
410
411static void *thunderx_gpio_populate_parent_alloc_info(struct gpio_chip *chip,
412						      unsigned int parent_hwirq,
413						      unsigned int parent_type)
414{
415	msi_alloc_info_t *info;
416
417	info = kmalloc(sizeof(*info), GFP_KERNEL);
418	if (!info)
419		return NULL;
420
421	info->hwirq = parent_hwirq;
422	return info;
423}
424
425static int thunderx_gpio_probe(struct pci_dev *pdev,
426			       const struct pci_device_id *id)
427{
428	void __iomem * const *tbl;
429	struct device *dev = &pdev->dev;
430	struct thunderx_gpio *txgpio;
431	struct gpio_chip *chip;
432	struct gpio_irq_chip *girq;
433	int ngpio, i;
434	int err = 0;
435
436	txgpio = devm_kzalloc(dev, sizeof(*txgpio), GFP_KERNEL);
437	if (!txgpio)
438		return -ENOMEM;
439
440	raw_spin_lock_init(&txgpio->lock);
441	chip = &txgpio->chip;
442
443	pci_set_drvdata(pdev, txgpio);
444
445	err = pcim_enable_device(pdev);
446	if (err) {
447		dev_err(dev, "Failed to enable PCI device: err %d\n", err);
448		goto out;
449	}
450
451	err = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
452	if (err) {
453		dev_err(dev, "Failed to iomap PCI device: err %d\n", err);
454		goto out;
455	}
456
457	tbl = pcim_iomap_table(pdev);
458	txgpio->register_base = tbl[0];
459	if (!txgpio->register_base) {
460		dev_err(dev, "Cannot map PCI resource\n");
461		err = -ENOMEM;
462		goto out;
463	}
464
465	if (pdev->subsystem_device == 0xa10a) {
466		/* CN88XX has no GPIO_CONST register*/
467		ngpio = 50;
468		txgpio->base_msi = 48;
469	} else {
470		u64 c = readq(txgpio->register_base + GPIO_CONST);
471
472		ngpio = c & GPIO_CONST_GPIOS_MASK;
473		txgpio->base_msi = (c >> 8) & 0xff;
474	}
475
476	txgpio->msix_entries = devm_kcalloc(dev,
477					    ngpio, sizeof(struct msix_entry),
478					    GFP_KERNEL);
479	if (!txgpio->msix_entries) {
480		err = -ENOMEM;
481		goto out;
482	}
483
484	txgpio->line_entries = devm_kcalloc(dev,
485					    ngpio,
486					    sizeof(struct thunderx_line),
487					    GFP_KERNEL);
488	if (!txgpio->line_entries) {
489		err = -ENOMEM;
490		goto out;
491	}
492
493	for (i = 0; i < ngpio; i++) {
494		u64 bit_cfg = readq(txgpio->register_base + bit_cfg_reg(i));
495
496		txgpio->msix_entries[i].entry = txgpio->base_msi + (2 * i);
497		txgpio->line_entries[i].line = i;
498		txgpio->line_entries[i].txgpio = txgpio;
499		/*
500		 * If something has already programmed the pin, use
501		 * the existing glitch filter settings, otherwise go
502		 * to 400nS.
503		 */
504		txgpio->line_entries[i].fil_bits = bit_cfg ?
505			(bit_cfg & GPIO_BIT_CFG_FIL_MASK) : GLITCH_FILTER_400NS;
506
507		if ((bit_cfg & GPIO_BIT_CFG_TX_OE) && (bit_cfg & GPIO_BIT_CFG_TX_OD))
508			set_bit(i, txgpio->od_mask);
509		if (bit_cfg & GPIO_BIT_CFG_PIN_XOR)
510			set_bit(i, txgpio->invert_mask);
511	}
512
513
514	/* Enable all MSI-X for interrupts on all possible lines. */
515	err = pci_enable_msix_range(pdev, txgpio->msix_entries, ngpio, ngpio);
516	if (err < 0)
517		goto out;
518
519	chip->label = KBUILD_MODNAME;
520	chip->parent = dev;
521	chip->owner = THIS_MODULE;
522	chip->request = thunderx_gpio_request;
523	chip->base = -1; /* System allocated */
524	chip->can_sleep = false;
525	chip->ngpio = ngpio;
526	chip->get_direction = thunderx_gpio_get_direction;
527	chip->direction_input = thunderx_gpio_dir_in;
528	chip->get = thunderx_gpio_get;
529	chip->direction_output = thunderx_gpio_dir_out;
530	chip->set = thunderx_gpio_set;
531	chip->set_multiple = thunderx_gpio_set_multiple;
532	chip->set_config = thunderx_gpio_set_config;
533	girq = &chip->irq;
534	girq->chip = &thunderx_gpio_irq_chip;
535	girq->fwnode = of_node_to_fwnode(dev->of_node);
536	girq->parent_domain =
537		irq_get_irq_data(txgpio->msix_entries[0].vector)->domain;
538	girq->child_to_parent_hwirq = thunderx_gpio_child_to_parent_hwirq;
539	girq->populate_parent_alloc_arg = thunderx_gpio_populate_parent_alloc_info;
540	girq->handler = handle_bad_irq;
541	girq->default_type = IRQ_TYPE_NONE;
542
543	err = devm_gpiochip_add_data(dev, chip, txgpio);
544	if (err)
545		goto out;
546
547	/* Push on irq_data and the domain for each line. */
548	for (i = 0; i < ngpio; i++) {
549		struct irq_fwspec fwspec;
550
551		fwspec.fwnode = of_node_to_fwnode(dev->of_node);
552		fwspec.param_count = 2;
553		fwspec.param[0] = i;
554		fwspec.param[1] = IRQ_TYPE_NONE;
555		err = irq_domain_push_irq(girq->domain,
556					  txgpio->msix_entries[i].vector,
557					  &fwspec);
558		if (err < 0)
559			dev_err(dev, "irq_domain_push_irq: %d\n", err);
560	}
561
562	dev_info(dev, "ThunderX GPIO: %d lines with base %d.\n",
563		 ngpio, chip->base);
564	return 0;
565out:
566	pci_set_drvdata(pdev, NULL);
567	return err;
568}
569
570static void thunderx_gpio_remove(struct pci_dev *pdev)
571{
572	int i;
573	struct thunderx_gpio *txgpio = pci_get_drvdata(pdev);
574
575	for (i = 0; i < txgpio->chip.ngpio; i++)
576		irq_domain_pop_irq(txgpio->chip.irq.domain,
577				   txgpio->msix_entries[i].vector);
578
579	irq_domain_remove(txgpio->chip.irq.domain);
580
581	pci_set_drvdata(pdev, NULL);
582}
583
584static const struct pci_device_id thunderx_gpio_id_table[] = {
585	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xA00A) },
586	{ 0, }	/* end of table */
587};
588
589MODULE_DEVICE_TABLE(pci, thunderx_gpio_id_table);
590
591static struct pci_driver thunderx_gpio_driver = {
592	.name = KBUILD_MODNAME,
593	.id_table = thunderx_gpio_id_table,
594	.probe = thunderx_gpio_probe,
595	.remove = thunderx_gpio_remove,
596};
597
598module_pci_driver(thunderx_gpio_driver);
599
600MODULE_DESCRIPTION("Cavium Inc. ThunderX/OCTEON-TX GPIO Driver");
601MODULE_LICENSE("GPL");