1 files changed, 661 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-pruss-intc.c b/drivers/irqchip/irq-pruss-intc.c
new file mode 100644
index 000000000..fa8d89b02
--- /dev/null
+++ b/drivers/irqchip/irq-pruss-intc.c
@@ -0,0 +1,661 @@
+// 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_device.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 == 0) ? -EINVAL : 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 int 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);
+
+	return 0;
+}
+
+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 = 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");