drivers/irqchip/irq-pruss-intc.c - third_party/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * PRU-ICSS INTC IRQChip driver for various TI SoCs
  *
  * Copyright (C) 2016-2020 Texas Instruments Incorporated - http://www.ti.com/
  *
  * Author(s):
  *	Andrew F. Davis <afd@ti.com>
  *	Suman Anna <s-anna@ti.com>
  *	Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
  *
  * Copyright (C) 2019 David Lechner <david@lechnology.com>
  */

 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>

 /*
  * Number of host interrupts reaching the main MPU sub-system. Note that this
  * is not the same as the total number of host interrupts supported by the PRUSS
  * INTC instance
  */
 #define MAX_NUM_HOST_IRQS	8

 /* minimum starting host interrupt number for MPU */
 #define FIRST_PRU_HOST_INT	2

 /* PRU_ICSS_INTC registers */
 #define PRU_INTC_REVID		0x0000
 #define PRU_INTC_CR		0x0004
 #define PRU_INTC_GER		0x0010
 #define PRU_INTC_GNLR		0x001c
 #define PRU_INTC_SISR		0x0020
 #define PRU_INTC_SICR		0x0024
 #define PRU_INTC_EISR		0x0028
 #define PRU_INTC_EICR		0x002c
 #define PRU_INTC_HIEISR		0x0034
 #define PRU_INTC_HIDISR		0x0038
 #define PRU_INTC_GPIR		0x0080
 #define PRU_INTC_SRSR(x)	(0x0200 + (x) * 4)
 #define PRU_INTC_SECR(x)	(0x0280 + (x) * 4)
 #define PRU_INTC_ESR(x)		(0x0300 + (x) * 4)
 #define PRU_INTC_ECR(x)		(0x0380 + (x) * 4)
 #define PRU_INTC_CMR(x)		(0x0400 + (x) * 4)
 #define PRU_INTC_HMR(x)		(0x0800 + (x) * 4)
 #define PRU_INTC_HIPIR(x)	(0x0900 + (x) * 4)
 #define PRU_INTC_SIPR(x)	(0x0d00 + (x) * 4)
 #define PRU_INTC_SITR(x)	(0x0d80 + (x) * 4)
 #define PRU_INTC_HINLR(x)	(0x1100 + (x) * 4)
 #define PRU_INTC_HIER		0x1500

 /* CMR register bit-field macros */
 #define CMR_EVT_MAP_MASK	0xf
 #define CMR_EVT_MAP_BITS	8
 #define CMR_EVT_PER_REG		4

 /* HMR register bit-field macros */
 #define HMR_CH_MAP_MASK		0xf
 #define HMR_CH_MAP_BITS		8
 #define HMR_CH_PER_REG		4

 /* HIPIR register bit-fields */
 #define INTC_HIPIR_NONE_HINT	0x80000000

 #define MAX_PRU_SYS_EVENTS 160
 #define MAX_PRU_CHANNELS 20

 /**
  * struct pruss_intc_map_record - keeps track of actual mapping state
  * @value: The currently mapped value (channel or host)
  * @ref_count: Keeps track of number of current users of this resource
  */
 struct pruss_intc_map_record {
 	u8 value;
 	u8 ref_count;
 };

 /**
  * struct pruss_intc_match_data - match data to handle SoC variations
  * @num_system_events: number of input system events handled by the PRUSS INTC
  * @num_host_events: number of host events (which is equal to number of
  *		     channels) supported by the PRUSS INTC
  */
 struct pruss_intc_match_data {
 	u8 num_system_events;
 	u8 num_host_events;
 };

 /**
  * struct pruss_intc - PRUSS interrupt controller structure
  * @event_channel: current state of system event to channel mappings
  * @channel_host: current state of channel to host mappings
  * @irqs: kernel irq numbers corresponding to PRUSS host interrupts
  * @base: base virtual address of INTC register space
  * @domain: irq domain for this interrupt controller
  * @soc_config: cached PRUSS INTC IP configuration data
  * @dev: PRUSS INTC device pointer
  * @lock: mutex to serialize interrupts mapping
  */
 struct pruss_intc {
 	struct pruss_intc_map_record event_channel[MAX_PRU_SYS_EVENTS];
 	struct pruss_intc_map_record channel_host[MAX_PRU_CHANNELS];
 	unsigned int irqs[MAX_NUM_HOST_IRQS];
 	void __iomem *base;
 	struct irq_domain *domain;
 	const struct pruss_intc_match_data *soc_config;
 	struct device *dev;
 	struct mutex lock; /* PRUSS INTC lock */
 };

 /**
  * struct pruss_host_irq_data - PRUSS host irq data structure
  * @intc: PRUSS interrupt controller pointer
  * @host_irq: host irq number
  */
 struct pruss_host_irq_data {
 	struct pruss_intc *intc;
 	u8 host_irq;
 };

 static inline u32 pruss_intc_read_reg(struct pruss_intc *intc, unsigned int reg)
 {
 	return readl_relaxed(intc->base + reg);
 }

 static inline void pruss_intc_write_reg(struct pruss_intc *intc,
 					unsigned int reg, u32 val)
 {
 	writel_relaxed(val, intc->base + reg);
 }

 static void pruss_intc_update_cmr(struct pruss_intc *intc, unsigned int evt,
 				  u8 ch)
 {
 	u32 idx, offset, val;

 	idx = evt / CMR_EVT_PER_REG;
 	offset = (evt % CMR_EVT_PER_REG) * CMR_EVT_MAP_BITS;

 	val = pruss_intc_read_reg(intc, PRU_INTC_CMR(idx));
 	val &= ~(CMR_EVT_MAP_MASK << offset);
 	val |= ch << offset;
 	pruss_intc_write_reg(intc, PRU_INTC_CMR(idx), val);

 	dev_dbg(intc->dev, "SYSEV%u -> CH%d (CMR%d 0x%08x)\n", evt, ch,
 		idx, pruss_intc_read_reg(intc, PRU_INTC_CMR(idx)));
 }

 static void pruss_intc_update_hmr(struct pruss_intc *intc, u8 ch, u8 host)
 {
 	u32 idx, offset, val;

 	idx = ch / HMR_CH_PER_REG;
 	offset = (ch % HMR_CH_PER_REG) * HMR_CH_MAP_BITS;

 	val = pruss_intc_read_reg(intc, PRU_INTC_HMR(idx));
 	val &= ~(HMR_CH_MAP_MASK << offset);
 	val |= host << offset;
 	pruss_intc_write_reg(intc, PRU_INTC_HMR(idx), val);

 	dev_dbg(intc->dev, "CH%d -> HOST%d (HMR%d 0x%08x)\n", ch, host, idx,
 		pruss_intc_read_reg(intc, PRU_INTC_HMR(idx)));
 }

 /**
  * pruss_intc_map() - configure the PRUSS INTC
  * @intc: PRUSS interrupt controller pointer
  * @hwirq: the system event number
  *
  * Configures the PRUSS INTC with the provided configuration from the one parsed
  * in the xlate function.
  */
 static void pruss_intc_map(struct pruss_intc *intc, unsigned long hwirq)
 {
 	struct device *dev = intc->dev;
 	u8 ch, host, reg_idx;
 	u32 val;

 	mutex_lock(&intc->lock);

 	intc->event_channel[hwirq].ref_count++;

 	ch = intc->event_channel[hwirq].value;
 	host = intc->channel_host[ch].value;

 	pruss_intc_update_cmr(intc, hwirq, ch);

 	reg_idx = hwirq / 32;
 	val = BIT(hwirq  % 32);

 	/* clear and enable system event */
 	pruss_intc_write_reg(intc, PRU_INTC_ESR(reg_idx), val);
 	pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val);

 	if (++intc->channel_host[ch].ref_count == 1) {
 		pruss_intc_update_hmr(intc, ch, host);

 		/* enable host interrupts */
 		pruss_intc_write_reg(intc, PRU_INTC_HIEISR, host);
 	}

 	dev_dbg(dev, "mapped system_event = %lu channel = %d host = %d",
 		hwirq, ch, host);

 	mutex_unlock(&intc->lock);
 }

 /**
  * pruss_intc_unmap() - unconfigure the PRUSS INTC
  * @intc: PRUSS interrupt controller pointer
  * @hwirq: the system event number
  *
  * Undo whatever was done in pruss_intc_map() for a PRU core.
  * Mappings are reference counted, so resources are only disabled when there
  * are no longer any users.
  */
 static void pruss_intc_unmap(struct pruss_intc *intc, unsigned long hwirq)
 {
 	u8 ch, host, reg_idx;
 	u32 val;

 	mutex_lock(&intc->lock);

 	ch = intc->event_channel[hwirq].value;
 	host = intc->channel_host[ch].value;

 	if (--intc->channel_host[ch].ref_count == 0) {
 		/* disable host interrupts */
 		pruss_intc_write_reg(intc, PRU_INTC_HIDISR, host);

 		/* clear the map using reset value 0 */
 		pruss_intc_update_hmr(intc, ch, 0);
 	}

 	intc->event_channel[hwirq].ref_count--;
 	reg_idx = hwirq / 32;
 	val = BIT(hwirq  % 32);

 	/* disable system events */
 	pruss_intc_write_reg(intc, PRU_INTC_ECR(reg_idx), val);
 	/* clear any pending status */
 	pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val);

 	/* clear the map using reset value 0 */
 	pruss_intc_update_cmr(intc, hwirq, 0);

 	dev_dbg(intc->dev, "unmapped system_event = %lu channel = %d host = %d\n",
 		hwirq, ch, host);

 	mutex_unlock(&intc->lock);
 }

 static void pruss_intc_init(struct pruss_intc *intc)
 {
 	const struct pruss_intc_match_data *soc_config = intc->soc_config;
 	int num_chnl_map_regs, num_host_intr_regs, num_event_type_regs, i;

 	num_chnl_map_regs = DIV_ROUND_UP(soc_config->num_system_events,
 					 CMR_EVT_PER_REG);
 	num_host_intr_regs = DIV_ROUND_UP(soc_config->num_host_events,
 					  HMR_CH_PER_REG);
 	num_event_type_regs = DIV_ROUND_UP(soc_config->num_system_events, 32);

 	/*
 	 * configure polarity (SIPR register) to active high and
 	 * type (SITR register) to level interrupt for all system events
 	 */
 	for (i = 0; i < num_event_type_regs; i++) {
 		pruss_intc_write_reg(intc, PRU_INTC_SIPR(i), 0xffffffff);
 		pruss_intc_write_reg(intc, PRU_INTC_SITR(i), 0);
 	}

 	/* clear all interrupt channel map registers, 4 events per register */
 	for (i = 0; i < num_chnl_map_regs; i++)
 		pruss_intc_write_reg(intc, PRU_INTC_CMR(i), 0);

 	/* clear all host interrupt map registers, 4 channels per register */
 	for (i = 0; i < num_host_intr_regs; i++)
 		pruss_intc_write_reg(intc, PRU_INTC_HMR(i), 0);

 	/* global interrupt enable */
 	pruss_intc_write_reg(intc, PRU_INTC_GER, 1);
 }

 static void pruss_intc_irq_ack(struct irq_data *data)
 {
 	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
 	unsigned int hwirq = data->hwirq;

 	pruss_intc_write_reg(intc, PRU_INTC_SICR, hwirq);
 }

 static void pruss_intc_irq_mask(struct irq_data *data)
 {
 	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
 	unsigned int hwirq = data->hwirq;

 	pruss_intc_write_reg(intc, PRU_INTC_EICR, hwirq);
 }

 static void pruss_intc_irq_unmask(struct irq_data *data)
 {
 	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
 	unsigned int hwirq = data->hwirq;

 	pruss_intc_write_reg(intc, PRU_INTC_EISR, hwirq);
 }

 static int pruss_intc_irq_reqres(struct irq_data *data)
 {
 	if (!try_module_get(THIS_MODULE))
 		return -ENODEV;

 	return 0;
 }

 static void pruss_intc_irq_relres(struct irq_data *data)
 {
 	module_put(THIS_MODULE);
 }

 static int pruss_intc_irq_get_irqchip_state(struct irq_data *data,
 					    enum irqchip_irq_state which,
 					    bool *state)
 {
 	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
 	u32 reg, mask, srsr;

 	if (which != IRQCHIP_STATE_PENDING)
 		return -EINVAL;

 	reg = PRU_INTC_SRSR(data->hwirq / 32);
 	mask = BIT(data->hwirq % 32);

 	srsr = pruss_intc_read_reg(intc, reg);

 	*state = !!(srsr & mask);

 	return 0;
 }

 static int pruss_intc_irq_set_irqchip_state(struct irq_data *data,
 					    enum irqchip_irq_state which,
 					    bool state)
 {
 	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);

 	if (which != IRQCHIP_STATE_PENDING)
 		return -EINVAL;

 	if (state)
 		pruss_intc_write_reg(intc, PRU_INTC_SISR, data->hwirq);
 	else
 		pruss_intc_write_reg(intc, PRU_INTC_SICR, data->hwirq);

 	return 0;
 }

 static struct irq_chip pruss_irqchip = {
 	.name			= "pruss-intc",
 	.irq_ack		= pruss_intc_irq_ack,
 	.irq_mask		= pruss_intc_irq_mask,
 	.irq_unmask		= pruss_intc_irq_unmask,
 	.irq_request_resources	= pruss_intc_irq_reqres,
 	.irq_release_resources	= pruss_intc_irq_relres,
 	.irq_get_irqchip_state	= pruss_intc_irq_get_irqchip_state,
 	.irq_set_irqchip_state	= pruss_intc_irq_set_irqchip_state,
 };

 static int pruss_intc_validate_mapping(struct pruss_intc *intc, int event,
 				       int channel, int host)
 {
 	struct device *dev = intc->dev;
 	int ret = 0;

 	mutex_lock(&intc->lock);

 	/* check if sysevent already assigned */
 	if (intc->event_channel[event].ref_count > 0 &&
 	    intc->event_channel[event].value != channel) {
 		dev_err(dev, "event %d (req. ch %d) already assigned to channel %d\n",
 			event, channel, intc->event_channel[event].value);
 		ret = -EBUSY;
 		goto unlock;
 	}

 	/* check if channel already assigned */
 	if (intc->channel_host[channel].ref_count > 0 &&
 	    intc->channel_host[channel].value != host) {
 		dev_err(dev, "channel %d (req. host %d) already assigned to host %d\n",
 			channel, host, intc->channel_host[channel].value);
 		ret = -EBUSY;
 		goto unlock;
 	}

 	intc->event_channel[event].value = channel;
 	intc->channel_host[channel].value = host;

 unlock:
 	mutex_unlock(&intc->lock);
 	return ret;
 }

 static int
 pruss_intc_irq_domain_xlate(struct irq_domain *d, struct device_node *node,
 			    const u32 *intspec, unsigned int intsize,
 			    unsigned long *out_hwirq, unsigned int *out_type)
 {
 	struct pruss_intc *intc = d->host_data;
 	struct device *dev = intc->dev;
 	int ret, sys_event, channel, host;

 	if (intsize < 3)
 		return -EINVAL;

 	sys_event = intspec[0];
 	if (sys_event < 0 || sys_event >= intc->soc_config->num_system_events) {
 		dev_err(dev, "%d is not valid event number\n", sys_event);
 		return -EINVAL;
 	}

 	channel = intspec[1];
 	if (channel < 0 || channel >= intc->soc_config->num_host_events) {
 		dev_err(dev, "%d is not valid channel number", channel);
 		return -EINVAL;
 	}

 	host = intspec[2];
 	if (host < 0 || host >= intc->soc_config->num_host_events) {
 		dev_err(dev, "%d is not valid host irq number\n", host);
 		return -EINVAL;
 	}

 	/* check if requested sys_event was already mapped, if so validate it */
 	ret = pruss_intc_validate_mapping(intc, sys_event, channel, host);
 	if (ret)
 		return ret;

 	*out_hwirq = sys_event;
 	*out_type = IRQ_TYPE_LEVEL_HIGH;

 	return 0;
 }

 static int pruss_intc_irq_domain_map(struct irq_domain *d, unsigned int virq,
 				     irq_hw_number_t hw)
 {
 	struct pruss_intc *intc = d->host_data;

 	pruss_intc_map(intc, hw);

 	irq_set_chip_data(virq, intc);
 	irq_set_chip_and_handler(virq, &pruss_irqchip, handle_level_irq);

 	return 0;
 }

 static void pruss_intc_irq_domain_unmap(struct irq_domain *d, unsigned int virq)
 {
 	struct pruss_intc *intc = d->host_data;
 	unsigned long hwirq = irqd_to_hwirq(irq_get_irq_data(virq));

 	irq_set_chip_and_handler(virq, NULL, NULL);
 	irq_set_chip_data(virq, NULL);
 	pruss_intc_unmap(intc, hwirq);
 }

 static const struct irq_domain_ops pruss_intc_irq_domain_ops = {
 	.xlate	= pruss_intc_irq_domain_xlate,
 	.map	= pruss_intc_irq_domain_map,
 	.unmap	= pruss_intc_irq_domain_unmap,
 };

 static void pruss_intc_irq_handler(struct irq_desc *desc)
 {
 	unsigned int irq = irq_desc_get_irq(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
 	struct pruss_host_irq_data *host_irq_data = irq_get_handler_data(irq);
 	struct pruss_intc *intc = host_irq_data->intc;
 	u8 host_irq = host_irq_data->host_irq + FIRST_PRU_HOST_INT;

 	chained_irq_enter(chip, desc);

 	while (true) {
 		u32 hipir;
 		int hwirq, err;

 		/* get highest priority pending PRUSS system event */
 		hipir = pruss_intc_read_reg(intc, PRU_INTC_HIPIR(host_irq));
 		if (hipir & INTC_HIPIR_NONE_HINT)
 			break;

 		hwirq = hipir & GENMASK(9, 0);
 		err = generic_handle_domain_irq(intc->domain, hwirq);

 		/*
 		 * NOTE: manually ACK any system events that do not have a
 		 * handler mapped yet
 		 */
 		if (WARN_ON_ONCE(err))
 			pruss_intc_write_reg(intc, PRU_INTC_SICR, hwirq);
 	}

 	chained_irq_exit(chip, desc);
 }

 static const char * const irq_names[MAX_NUM_HOST_IRQS] = {
 	"host_intr0", "host_intr1", "host_intr2", "host_intr3",
 	"host_intr4", "host_intr5", "host_intr6", "host_intr7",
 };

 static int pruss_intc_probe(struct platform_device *pdev)
 {
 	const struct pruss_intc_match_data *data;
 	struct device *dev = &pdev->dev;
 	struct pruss_intc *intc;
 	struct pruss_host_irq_data *host_data;
 	int i, irq, ret;
 	u8 max_system_events, irqs_reserved = 0;

 	data = of_device_get_match_data(dev);
 	if (!data)
 		return -ENODEV;

 	max_system_events = data->num_system_events;

 	intc = devm_kzalloc(dev, sizeof(*intc), GFP_KERNEL);
 	if (!intc)
 		return -ENOMEM;

 	intc->soc_config = data;
 	intc->dev = dev;
 	platform_set_drvdata(pdev, intc);

 	intc->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(intc->base))
 		return PTR_ERR(intc->base);

 	ret = of_property_read_u8(dev->of_node, "ti,irqs-reserved",
 				  &irqs_reserved);

 	/*
 	 * The irqs-reserved is used only for some SoC's therefore not having
 	 * this property is still valid
 	 */
 	if (ret < 0 && ret != -EINVAL)
 		return ret;

 	pruss_intc_init(intc);

 	mutex_init(&intc->lock);

 	intc->domain = irq_domain_add_linear(dev->of_node, max_system_events,
 					     &pruss_intc_irq_domain_ops, intc);
 	if (!intc->domain)
 		return -ENOMEM;

 	for (i = 0; i < MAX_NUM_HOST_IRQS; i++) {
 		if (irqs_reserved & BIT(i))
 			continue;

 		irq = platform_get_irq_byname(pdev, irq_names[i]);
 		if (irq < 0) {
 			ret = irq;
 			goto fail_irq;
 		}

 		intc->irqs[i] = irq;

 		host_data = devm_kzalloc(dev, sizeof(*host_data), GFP_KERNEL);
 		if (!host_data) {
 			ret = -ENOMEM;
 			goto fail_irq;
 		}

 		host_data->intc = intc;
 		host_data->host_irq = i;

 		irq_set_handler_data(irq, host_data);
 		irq_set_chained_handler(irq, pruss_intc_irq_handler);
 	}

 	return 0;

 fail_irq:
 	while (--i >= 0) {
 		if (intc->irqs[i])
 			irq_set_chained_handler_and_data(intc->irqs[i], NULL,
 							 NULL);
 	}

 	irq_domain_remove(intc->domain);

 	return ret;
 }

 static void pruss_intc_remove(struct platform_device *pdev)
 {
 	struct pruss_intc *intc = platform_get_drvdata(pdev);
 	u8 max_system_events = intc->soc_config->num_system_events;
 	unsigned int hwirq;
 	int i;

 	for (i = 0; i < MAX_NUM_HOST_IRQS; i++) {
 		if (intc->irqs[i])
 			irq_set_chained_handler_and_data(intc->irqs[i], NULL,
 							 NULL);
 	}

 	for (hwirq = 0; hwirq < max_system_events; hwirq++)
 		irq_dispose_mapping(irq_find_mapping(intc->domain, hwirq));

 	irq_domain_remove(intc->domain);
 }

 static const struct pruss_intc_match_data pruss_intc_data = {
 	.num_system_events = 64,
 	.num_host_events = 10,
 };

 static const struct pruss_intc_match_data icssg_intc_data = {
 	.num_system_events = 160,
 	.num_host_events = 20,
 };

 static const struct of_device_id pruss_intc_of_match[] = {
 	{
 		.compatible = "ti,pruss-intc",
 		.data = &pruss_intc_data,
 	},
 	{
 		.compatible = "ti,icssg-intc",
 		.data = &icssg_intc_data,
 	},
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, pruss_intc_of_match);

 static struct platform_driver pruss_intc_driver = {
 	.driver = {
 		.name			= "pruss-intc",
 		.of_match_table		= pruss_intc_of_match,
 		.suppress_bind_attrs	= true,
 	},
 	.probe		= pruss_intc_probe,
 	.remove_new	= pruss_intc_remove,
 };
 module_platform_driver(pruss_intc_driver);

 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
 MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
 MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
 MODULE_DESCRIPTION("TI PRU-ICSS INTC Driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* PRU-ICSS INTC IRQChip driver for various TI SoCs
	*
	* Copyright (C) 2016-2020 Texas Instruments Incorporated - http://www.ti.com/
	*
	* Author(s):
	* Andrew F. Davis <afd@ti.com>
	* Suman Anna <s-anna@ti.com>
	* Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
	*
	* Copyright (C) 2019 David Lechner <david@lechnology.com>
	*/

	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/irqchip/chained_irq.h>
	#include <linux/irqdomain.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>

	/*
	* Number of host interrupts reaching the main MPU sub-system. Note that this
	* is not the same as the total number of host interrupts supported by the PRUSS
	* INTC instance
	*/
	#define MAX_NUM_HOST_IRQS 8

	/* minimum starting host interrupt number for MPU */
	#define FIRST_PRU_HOST_INT 2

	/* PRU_ICSS_INTC registers */
	#define PRU_INTC_REVID 0x0000
	#define PRU_INTC_CR 0x0004
	#define PRU_INTC_GER 0x0010
	#define PRU_INTC_GNLR 0x001c
	#define PRU_INTC_SISR 0x0020
	#define PRU_INTC_SICR 0x0024
	#define PRU_INTC_EISR 0x0028
	#define PRU_INTC_EICR 0x002c
	#define PRU_INTC_HIEISR 0x0034
	#define PRU_INTC_HIDISR 0x0038
	#define PRU_INTC_GPIR 0x0080
	#define PRU_INTC_SRSR(x) (0x0200 + (x) * 4)
	#define PRU_INTC_SECR(x) (0x0280 + (x) * 4)
	#define PRU_INTC_ESR(x) (0x0300 + (x) * 4)
	#define PRU_INTC_ECR(x) (0x0380 + (x) * 4)
	#define PRU_INTC_CMR(x) (0x0400 + (x) * 4)
	#define PRU_INTC_HMR(x) (0x0800 + (x) * 4)
	#define PRU_INTC_HIPIR(x) (0x0900 + (x) * 4)
	#define PRU_INTC_SIPR(x) (0x0d00 + (x) * 4)
	#define PRU_INTC_SITR(x) (0x0d80 + (x) * 4)
	#define PRU_INTC_HINLR(x) (0x1100 + (x) * 4)
	#define PRU_INTC_HIER 0x1500

	/* CMR register bit-field macros */
	#define CMR_EVT_MAP_MASK 0xf
	#define CMR_EVT_MAP_BITS 8
	#define CMR_EVT_PER_REG 4

	/* HMR register bit-field macros */
	#define HMR_CH_MAP_MASK 0xf
	#define HMR_CH_MAP_BITS 8
	#define HMR_CH_PER_REG 4

	/* HIPIR register bit-fields */
	#define INTC_HIPIR_NONE_HINT 0x80000000

	#define MAX_PRU_SYS_EVENTS 160
	#define MAX_PRU_CHANNELS 20

	/**
	* struct pruss_intc_map_record - keeps track of actual mapping state
	* @value: The currently mapped value (channel or host)
	* @ref_count: Keeps track of number of current users of this resource
	*/
	struct pruss_intc_map_record {
	u8 value;
	u8 ref_count;
	};

	/**
	* struct pruss_intc_match_data - match data to handle SoC variations
	* @num_system_events: number of input system events handled by the PRUSS INTC
	* @num_host_events: number of host events (which is equal to number of
	* channels) supported by the PRUSS INTC
	*/
	struct pruss_intc_match_data {
	u8 num_system_events;
	u8 num_host_events;
	};

	/**
	* struct pruss_intc - PRUSS interrupt controller structure
	* @event_channel: current state of system event to channel mappings
	* @channel_host: current state of channel to host mappings
	* @irqs: kernel irq numbers corresponding to PRUSS host interrupts
	* @base: base virtual address of INTC register space
	* @domain: irq domain for this interrupt controller
	* @soc_config: cached PRUSS INTC IP configuration data
	* @dev: PRUSS INTC device pointer
	* @lock: mutex to serialize interrupts mapping
	*/
	struct pruss_intc {
	struct pruss_intc_map_record event_channel[MAX_PRU_SYS_EVENTS];
	struct pruss_intc_map_record channel_host[MAX_PRU_CHANNELS];
	unsigned int irqs[MAX_NUM_HOST_IRQS];
	void __iomem *base;
	struct irq_domain *domain;
	const struct pruss_intc_match_data *soc_config;
	struct device *dev;
	struct mutex lock; /* PRUSS INTC lock */
	};

	/**
	* struct pruss_host_irq_data - PRUSS host irq data structure
	* @intc: PRUSS interrupt controller pointer
	* @host_irq: host irq number
	*/
	struct pruss_host_irq_data {
	struct pruss_intc *intc;
	u8 host_irq;
	};

	static inline u32 pruss_intc_read_reg(struct pruss_intc *intc, unsigned int reg)
	{
	return readl_relaxed(intc->base + reg);
	}

	static inline void pruss_intc_write_reg(struct pruss_intc *intc,
	unsigned int reg, u32 val)
	{
	writel_relaxed(val, intc->base + reg);
	}

	static void pruss_intc_update_cmr(struct pruss_intc *intc, unsigned int evt,
	u8 ch)
	{
	u32 idx, offset, val;

	idx = evt / CMR_EVT_PER_REG;
	offset = (evt % CMR_EVT_PER_REG) * CMR_EVT_MAP_BITS;

	val = pruss_intc_read_reg(intc, PRU_INTC_CMR(idx));
	val &= ~(CMR_EVT_MAP_MASK << offset);
	val \|= ch << offset;
	pruss_intc_write_reg(intc, PRU_INTC_CMR(idx), val);

	dev_dbg(intc->dev, "SYSEV%u -> CH%d (CMR%d 0x%08x)\n", evt, ch,
	idx, pruss_intc_read_reg(intc, PRU_INTC_CMR(idx)));
	}

	static void pruss_intc_update_hmr(struct pruss_intc *intc, u8 ch, u8 host)
	{
	u32 idx, offset, val;

	idx = ch / HMR_CH_PER_REG;
	offset = (ch % HMR_CH_PER_REG) * HMR_CH_MAP_BITS;

	val = pruss_intc_read_reg(intc, PRU_INTC_HMR(idx));
	val &= ~(HMR_CH_MAP_MASK << offset);
	val \|= host << offset;
	pruss_intc_write_reg(intc, PRU_INTC_HMR(idx), val);

	dev_dbg(intc->dev, "CH%d -> HOST%d (HMR%d 0x%08x)\n", ch, host, idx,
	pruss_intc_read_reg(intc, PRU_INTC_HMR(idx)));
	}

	/**
	* pruss_intc_map() - configure the PRUSS INTC
	* @intc: PRUSS interrupt controller pointer
	* @hwirq: the system event number
	*
	* Configures the PRUSS INTC with the provided configuration from the one parsed
	* in the xlate function.
	*/
	static void pruss_intc_map(struct pruss_intc *intc, unsigned long hwirq)
	{
	struct device *dev = intc->dev;
	u8 ch, host, reg_idx;
	u32 val;

	mutex_lock(&intc->lock);

	intc->event_channel[hwirq].ref_count++;

	ch = intc->event_channel[hwirq].value;
	host = intc->channel_host[ch].value;

	pruss_intc_update_cmr(intc, hwirq, ch);

	reg_idx = hwirq / 32;
	val = BIT(hwirq % 32);

	/* clear and enable system event */
	pruss_intc_write_reg(intc, PRU_INTC_ESR(reg_idx), val);
	pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val);

	if (++intc->channel_host[ch].ref_count == 1) {
	pruss_intc_update_hmr(intc, ch, host);

	/* enable host interrupts */
	pruss_intc_write_reg(intc, PRU_INTC_HIEISR, host);
	}

	dev_dbg(dev, "mapped system_event = %lu channel = %d host = %d",
	hwirq, ch, host);

	mutex_unlock(&intc->lock);
	}

	/**
	* pruss_intc_unmap() - unconfigure the PRUSS INTC
	* @intc: PRUSS interrupt controller pointer
	* @hwirq: the system event number
	*
	* Undo whatever was done in pruss_intc_map() for a PRU core.
	* Mappings are reference counted, so resources are only disabled when there
	* are no longer any users.
	*/
	static void pruss_intc_unmap(struct pruss_intc *intc, unsigned long hwirq)
	{
	u8 ch, host, reg_idx;
	u32 val;

	mutex_lock(&intc->lock);

	ch = intc->event_channel[hwirq].value;
	host = intc->channel_host[ch].value;

	if (--intc->channel_host[ch].ref_count == 0) {
	/* disable host interrupts */
	pruss_intc_write_reg(intc, PRU_INTC_HIDISR, host);

	/* clear the map using reset value 0 */
	pruss_intc_update_hmr(intc, ch, 0);
	}

	intc->event_channel[hwirq].ref_count--;
	reg_idx = hwirq / 32;
	val = BIT(hwirq % 32);

	/* disable system events */
	pruss_intc_write_reg(intc, PRU_INTC_ECR(reg_idx), val);
	/* clear any pending status */
	pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val);

	/* clear the map using reset value 0 */
	pruss_intc_update_cmr(intc, hwirq, 0);

	dev_dbg(intc->dev, "unmapped system_event = %lu channel = %d host = %d\n",
	hwirq, ch, host);

	mutex_unlock(&intc->lock);
	}

	static void pruss_intc_init(struct pruss_intc *intc)
	{
	const struct pruss_intc_match_data *soc_config = intc->soc_config;
	int num_chnl_map_regs, num_host_intr_regs, num_event_type_regs, i;

	num_chnl_map_regs = DIV_ROUND_UP(soc_config->num_system_events,
	CMR_EVT_PER_REG);
	num_host_intr_regs = DIV_ROUND_UP(soc_config->num_host_events,
	HMR_CH_PER_REG);
	num_event_type_regs = DIV_ROUND_UP(soc_config->num_system_events, 32);

	/*
	* configure polarity (SIPR register) to active high and
	* type (SITR register) to level interrupt for all system events
	*/
	for (i = 0; i < num_event_type_regs; i++) {
	pruss_intc_write_reg(intc, PRU_INTC_SIPR(i), 0xffffffff);
	pruss_intc_write_reg(intc, PRU_INTC_SITR(i), 0);
	}

	/* clear all interrupt channel map registers, 4 events per register */
	for (i = 0; i < num_chnl_map_regs; i++)
	pruss_intc_write_reg(intc, PRU_INTC_CMR(i), 0);

	/* clear all host interrupt map registers, 4 channels per register */
	for (i = 0; i < num_host_intr_regs; i++)
	pruss_intc_write_reg(intc, PRU_INTC_HMR(i), 0);

	/* global interrupt enable */
	pruss_intc_write_reg(intc, PRU_INTC_GER, 1);
	}

	static void pruss_intc_irq_ack(struct irq_data *data)
	{
	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
	unsigned int hwirq = data->hwirq;

	pruss_intc_write_reg(intc, PRU_INTC_SICR, hwirq);
	}

	static void pruss_intc_irq_mask(struct irq_data *data)
	{
	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
	unsigned int hwirq = data->hwirq;

	pruss_intc_write_reg(intc, PRU_INTC_EICR, hwirq);
	}

	static void pruss_intc_irq_unmask(struct irq_data *data)
	{
	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
	unsigned int hwirq = data->hwirq;

	pruss_intc_write_reg(intc, PRU_INTC_EISR, hwirq);
	}

	static int pruss_intc_irq_reqres(struct irq_data *data)
	{
	if (!try_module_get(THIS_MODULE))
	return -ENODEV;

	return 0;
	}

	static void pruss_intc_irq_relres(struct irq_data *data)
	{
	module_put(THIS_MODULE);
	}

	static int pruss_intc_irq_get_irqchip_state(struct irq_data *data,
	enum irqchip_irq_state which,
	bool *state)
	{
	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);
	u32 reg, mask, srsr;

	if (which != IRQCHIP_STATE_PENDING)
	return -EINVAL;

	reg = PRU_INTC_SRSR(data->hwirq / 32);
	mask = BIT(data->hwirq % 32);

	srsr = pruss_intc_read_reg(intc, reg);

	*state = !!(srsr & mask);

	return 0;
	}

	static int pruss_intc_irq_set_irqchip_state(struct irq_data *data,
	enum irqchip_irq_state which,
	bool state)
	{
	struct pruss_intc *intc = irq_data_get_irq_chip_data(data);

	if (which != IRQCHIP_STATE_PENDING)
	return -EINVAL;

	if (state)
	pruss_intc_write_reg(intc, PRU_INTC_SISR, data->hwirq);
	else
	pruss_intc_write_reg(intc, PRU_INTC_SICR, data->hwirq);

	return 0;
	}

	static struct irq_chip pruss_irqchip = {
	.name = "pruss-intc",
	.irq_ack = pruss_intc_irq_ack,
	.irq_mask = pruss_intc_irq_mask,
	.irq_unmask = pruss_intc_irq_unmask,
	.irq_request_resources = pruss_intc_irq_reqres,
	.irq_release_resources = pruss_intc_irq_relres,
	.irq_get_irqchip_state = pruss_intc_irq_get_irqchip_state,
	.irq_set_irqchip_state = pruss_intc_irq_set_irqchip_state,
	};

	static int pruss_intc_validate_mapping(struct pruss_intc *intc, int event,
	int channel, int host)
	{
	struct device *dev = intc->dev;
	int ret = 0;

	mutex_lock(&intc->lock);

	/* check if sysevent already assigned */
	if (intc->event_channel[event].ref_count > 0 &&
	intc->event_channel[event].value != channel) {
	dev_err(dev, "event %d (req. ch %d) already assigned to channel %d\n",
	event, channel, intc->event_channel[event].value);
	ret = -EBUSY;
	goto unlock;
	}

	/* check if channel already assigned */
	if (intc->channel_host[channel].ref_count > 0 &&
	intc->channel_host[channel].value != host) {
	dev_err(dev, "channel %d (req. host %d) already assigned to host %d\n",
	channel, host, intc->channel_host[channel].value);
	ret = -EBUSY;
	goto unlock;
	}

	intc->event_channel[event].value = channel;
	intc->channel_host[channel].value = host;

	unlock:
	mutex_unlock(&intc->lock);
	return ret;
	}

	static int
	pruss_intc_irq_domain_xlate(struct irq_domain d, struct device_node node,
	const u32 *intspec, unsigned int intsize,
	unsigned long out_hwirq, unsigned int out_type)
	{
	struct pruss_intc *intc = d->host_data;
	struct device *dev = intc->dev;
	int ret, sys_event, channel, host;

	if (intsize < 3)
	return -EINVAL;

	sys_event = intspec[0];
	if (sys_event < 0 \|\| sys_event >= intc->soc_config->num_system_events) {
	dev_err(dev, "%d is not valid event number\n", sys_event);
	return -EINVAL;
	}

	channel = intspec[1];
	if (channel < 0 \|\| channel >= intc->soc_config->num_host_events) {
	dev_err(dev, "%d is not valid channel number", channel);
	return -EINVAL;
	}

	host = intspec[2];
	if (host < 0 \|\| host >= intc->soc_config->num_host_events) {
	dev_err(dev, "%d is not valid host irq number\n", host);
	return -EINVAL;
	}

	/* check if requested sys_event was already mapped, if so validate it */
	ret = pruss_intc_validate_mapping(intc, sys_event, channel, host);
	if (ret)
	return ret;

	*out_hwirq = sys_event;
	*out_type = IRQ_TYPE_LEVEL_HIGH;

	return 0;
	}

	static int pruss_intc_irq_domain_map(struct irq_domain *d, unsigned int virq,
	irq_hw_number_t hw)
	{
	struct pruss_intc *intc = d->host_data;

	pruss_intc_map(intc, hw);

	irq_set_chip_data(virq, intc);
	irq_set_chip_and_handler(virq, &pruss_irqchip, handle_level_irq);

	return 0;
	}

	static void pruss_intc_irq_domain_unmap(struct irq_domain *d, unsigned int virq)
	{
	struct pruss_intc *intc = d->host_data;
	unsigned long hwirq = irqd_to_hwirq(irq_get_irq_data(virq));

	irq_set_chip_and_handler(virq, NULL, NULL);
	irq_set_chip_data(virq, NULL);
	pruss_intc_unmap(intc, hwirq);
	}

	static const struct irq_domain_ops pruss_intc_irq_domain_ops = {
	.xlate = pruss_intc_irq_domain_xlate,
	.map = pruss_intc_irq_domain_map,
	.unmap = pruss_intc_irq_domain_unmap,
	};

	static void pruss_intc_irq_handler(struct irq_desc *desc)
	{
	unsigned int irq = irq_desc_get_irq(desc);
	struct irq_chip *chip = irq_desc_get_chip(desc);
	struct pruss_host_irq_data *host_irq_data = irq_get_handler_data(irq);
	struct pruss_intc *intc = host_irq_data->intc;
	u8 host_irq = host_irq_data->host_irq + FIRST_PRU_HOST_INT;

	chained_irq_enter(chip, desc);

	while (true) {
	u32 hipir;
	int hwirq, err;

	/* get highest priority pending PRUSS system event */
	hipir = pruss_intc_read_reg(intc, PRU_INTC_HIPIR(host_irq));
	if (hipir & INTC_HIPIR_NONE_HINT)
	break;

	hwirq = hipir & GENMASK(9, 0);
	err = generic_handle_domain_irq(intc->domain, hwirq);

	/*
	* NOTE: manually ACK any system events that do not have a
	* handler mapped yet
	*/
	if (WARN_ON_ONCE(err))
	pruss_intc_write_reg(intc, PRU_INTC_SICR, hwirq);
	}

	chained_irq_exit(chip, desc);
	}

	static const char * const irq_names[MAX_NUM_HOST_IRQS] = {
	"host_intr0", "host_intr1", "host_intr2", "host_intr3",
	"host_intr4", "host_intr5", "host_intr6", "host_intr7",
	};

	static int pruss_intc_probe(struct platform_device *pdev)
	{
	const struct pruss_intc_match_data *data;
	struct device *dev = &pdev->dev;
	struct pruss_intc *intc;
	struct pruss_host_irq_data *host_data;
	int i, irq, ret;
	u8 max_system_events, irqs_reserved = 0;

	data = of_device_get_match_data(dev);
	if (!data)
	return -ENODEV;

	max_system_events = data->num_system_events;

	intc = devm_kzalloc(dev, sizeof(*intc), GFP_KERNEL);
	if (!intc)
	return -ENOMEM;

	intc->soc_config = data;
	intc->dev = dev;
	platform_set_drvdata(pdev, intc);

	intc->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(intc->base))
	return PTR_ERR(intc->base);

	ret = of_property_read_u8(dev->of_node, "ti,irqs-reserved",
	&irqs_reserved);

	/*
	* The irqs-reserved is used only for some SoC's therefore not having
	* this property is still valid
	*/
	if (ret < 0 && ret != -EINVAL)
	return ret;

	pruss_intc_init(intc);

	mutex_init(&intc->lock);

	intc->domain = irq_domain_add_linear(dev->of_node, max_system_events,
	&pruss_intc_irq_domain_ops, intc);
	if (!intc->domain)
	return -ENOMEM;

	for (i = 0; i < MAX_NUM_HOST_IRQS; i++) {
	if (irqs_reserved & BIT(i))
	continue;

	irq = platform_get_irq_byname(pdev, irq_names[i]);
	if (irq < 0) {
	ret = irq;
	goto fail_irq;
	}

	intc->irqs[i] = irq;

	host_data = devm_kzalloc(dev, sizeof(*host_data), GFP_KERNEL);
	if (!host_data) {
	ret = -ENOMEM;
	goto fail_irq;
	}

	host_data->intc = intc;
	host_data->host_irq = i;

	irq_set_handler_data(irq, host_data);
	irq_set_chained_handler(irq, pruss_intc_irq_handler);
	}

	return 0;

	fail_irq:
	while (--i >= 0) {
	if (intc->irqs[i])
	irq_set_chained_handler_and_data(intc->irqs[i], NULL,
	NULL);
	}

	irq_domain_remove(intc->domain);

	return ret;
	}

	static void pruss_intc_remove(struct platform_device *pdev)
	{
	struct pruss_intc *intc = platform_get_drvdata(pdev);
	u8 max_system_events = intc->soc_config->num_system_events;
	unsigned int hwirq;
	int i;

	for (i = 0; i < MAX_NUM_HOST_IRQS; i++) {
	if (intc->irqs[i])
	irq_set_chained_handler_and_data(intc->irqs[i], NULL,
	NULL);
	}

	for (hwirq = 0; hwirq < max_system_events; hwirq++)
	irq_dispose_mapping(irq_find_mapping(intc->domain, hwirq));

	irq_domain_remove(intc->domain);
	}

	static const struct pruss_intc_match_data pruss_intc_data = {
	.num_system_events = 64,
	.num_host_events = 10,
	};

	static const struct pruss_intc_match_data icssg_intc_data = {
	.num_system_events = 160,
	.num_host_events = 20,
	};

	static const struct of_device_id pruss_intc_of_match[] = {
	{
	.compatible = "ti,pruss-intc",
	.data = &pruss_intc_data,
	},
	{
	.compatible = "ti,icssg-intc",
	.data = &icssg_intc_data,
	},
	{ /* sentinel */ },
	};
	MODULE_DEVICE_TABLE(of, pruss_intc_of_match);

	static struct platform_driver pruss_intc_driver = {
	.driver = {
	.name = "pruss-intc",
	.of_match_table = pruss_intc_of_match,
	.suppress_bind_attrs = true,
	},
	.probe = pruss_intc_probe,
	.remove_new = pruss_intc_remove,
	};
	module_platform_driver(pruss_intc_driver);

	MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
	MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
	MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
	MODULE_DESCRIPTION("TI PRU-ICSS INTC Driver");
	MODULE_LICENSE("GPL v2");