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