Initial import

1 files changed, 614 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-renesas-intc-irqpin.c b/drivers/irqchip/irq-renesas-intc-irqpin.c
new file mode 100644
index 000000000..9a0767b9c
--- /dev/null
+++ b/drivers/irqchip/irq-renesas-intc-irqpin.c
@@ -0,0 +1,614 @@
+/*
+ * Renesas INTC External IRQ Pin Driver
+ *
+ *  Copyright (C) 2013 Magnus Damm
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/clk.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_data/irq-renesas-intc-irqpin.h>
+#include <linux/pm_runtime.h>
+
+#define INTC_IRQPIN_MAX 8 /* maximum 8 interrupts per driver instance */
+
+#define INTC_IRQPIN_REG_SENSE 0 /* ICRn */
+#define INTC_IRQPIN_REG_PRIO 1 /* INTPRInn */
+#define INTC_IRQPIN_REG_SOURCE 2 /* INTREQnn */
+#define INTC_IRQPIN_REG_MASK 3 /* INTMSKnn */
+#define INTC_IRQPIN_REG_CLEAR 4 /* INTMSKCLRnn */
+#define INTC_IRQPIN_REG_NR_MANDATORY 5
+#define INTC_IRQPIN_REG_IRLM 5 /* ICR0 with IRLM bit (optional) */
+#define INTC_IRQPIN_REG_NR 6
+
+/* INTC external IRQ PIN hardware register access:
+ *
+ * SENSE is read-write 32-bit with 2-bits or 4-bits per IRQ (*)
+ * PRIO is read-write 32-bit with 4-bits per IRQ (**)
+ * SOURCE is read-only 32-bit or 8-bit with 1-bit per IRQ (***)
+ * MASK is write-only 32-bit or 8-bit with 1-bit per IRQ (***)
+ * CLEAR is write-only 32-bit or 8-bit with 1-bit per IRQ (***)
+ *
+ * (*) May be accessed by more than one driver instance - lock needed
+ * (**) Read-modify-write access by one driver instance - lock needed
+ * (***) Accessed by one driver instance only - no locking needed
+ */
+
+struct intc_irqpin_iomem {
+	void __iomem *iomem;
+	unsigned long (*read)(void __iomem *iomem);
+	void (*write)(void __iomem *iomem, unsigned long data);
+	int width;
+};
+
+struct intc_irqpin_irq {
+	int hw_irq;
+	int requested_irq;
+	int domain_irq;
+	struct intc_irqpin_priv *p;
+};
+
+struct intc_irqpin_priv {
+	struct intc_irqpin_iomem iomem[INTC_IRQPIN_REG_NR];
+	struct intc_irqpin_irq irq[INTC_IRQPIN_MAX];
+	struct renesas_intc_irqpin_config config;
+	unsigned int number_of_irqs;
+	struct platform_device *pdev;
+	struct irq_chip irq_chip;
+	struct irq_domain *irq_domain;
+	struct clk *clk;
+	bool shared_irqs;
+	u8 shared_irq_mask;
+};
+
+struct intc_irqpin_irlm_config {
+	unsigned int irlm_bit;
+};
+
+static unsigned long intc_irqpin_read32(void __iomem *iomem)
+{
+	return ioread32(iomem);
+}
+
+static unsigned long intc_irqpin_read8(void __iomem *iomem)
+{
+	return ioread8(iomem);
+}
+
+static void intc_irqpin_write32(void __iomem *iomem, unsigned long data)
+{
+	iowrite32(data, iomem);
+}
+
+static void intc_irqpin_write8(void __iomem *iomem, unsigned long data)
+{
+	iowrite8(data, iomem);
+}
+
+static inline unsigned long intc_irqpin_read(struct intc_irqpin_priv *p,
+					     int reg)
+{
+	struct intc_irqpin_iomem *i = &p->iomem[reg];
+
+	return i->read(i->iomem);
+}
+
+static inline void intc_irqpin_write(struct intc_irqpin_priv *p,
+				     int reg, unsigned long data)
+{
+	struct intc_irqpin_iomem *i = &p->iomem[reg];
+
+	i->write(i->iomem, data);
+}
+
+static inline unsigned long intc_irqpin_hwirq_mask(struct intc_irqpin_priv *p,
+						   int reg, int hw_irq)
+{
+	return BIT((p->iomem[reg].width - 1) - hw_irq);
+}
+
+static inline void intc_irqpin_irq_write_hwirq(struct intc_irqpin_priv *p,
+					       int reg, int hw_irq)
+{
+	intc_irqpin_write(p, reg, intc_irqpin_hwirq_mask(p, reg, hw_irq));
+}
+
+static DEFINE_RAW_SPINLOCK(intc_irqpin_lock); /* only used by slow path */
+
+static void intc_irqpin_read_modify_write(struct intc_irqpin_priv *p,
+					  int reg, int shift,
+					  int width, int value)
+{
+	unsigned long flags;
+	unsigned long tmp;
+
+	raw_spin_lock_irqsave(&intc_irqpin_lock, flags);
+
+	tmp = intc_irqpin_read(p, reg);
+	tmp &= ~(((1 << width) - 1) << shift);
+	tmp |= value << shift;
+	intc_irqpin_write(p, reg, tmp);
+
+	raw_spin_unlock_irqrestore(&intc_irqpin_lock, flags);
+}
+
+static void intc_irqpin_mask_unmask_prio(struct intc_irqpin_priv *p,
+					 int irq, int do_mask)
+{
+	/* The PRIO register is assumed to be 32-bit with fixed 4-bit fields. */
+	int bitfield_width = 4;
+	int shift = 32 - (irq + 1) * bitfield_width;
+
+	intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_PRIO,
+				      shift, bitfield_width,
+				      do_mask ? 0 : (1 << bitfield_width) - 1);
+}
+
+static int intc_irqpin_set_sense(struct intc_irqpin_priv *p, int irq, int value)
+{
+	/* The SENSE register is assumed to be 32-bit. */
+	int bitfield_width = p->config.sense_bitfield_width;
+	int shift = 32 - (irq + 1) * bitfield_width;
+
+	dev_dbg(&p->pdev->dev, "sense irq = %d, mode = %d\n", irq, value);
+
+	if (value >= (1 << bitfield_width))
+		return -EINVAL;
+
+	intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_SENSE, shift,
+				      bitfield_width, value);
+	return 0;
+}
+
+static void intc_irqpin_dbg(struct intc_irqpin_irq *i, char *str)
+{
+	dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n",
+		str, i->requested_irq, i->hw_irq, i->domain_irq);
+}
+
+static void intc_irqpin_irq_enable(struct irq_data *d)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+	int hw_irq = irqd_to_hwirq(d);
+
+	intc_irqpin_dbg(&p->irq[hw_irq], "enable");
+	intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq);
+}
+
+static void intc_irqpin_irq_disable(struct irq_data *d)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+	int hw_irq = irqd_to_hwirq(d);
+
+	intc_irqpin_dbg(&p->irq[hw_irq], "disable");
+	intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq);
+}
+
+static void intc_irqpin_shared_irq_enable(struct irq_data *d)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+	int hw_irq = irqd_to_hwirq(d);
+
+	intc_irqpin_dbg(&p->irq[hw_irq], "shared enable");
+	intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq);
+
+	p->shared_irq_mask &= ~BIT(hw_irq);
+}
+
+static void intc_irqpin_shared_irq_disable(struct irq_data *d)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+	int hw_irq = irqd_to_hwirq(d);
+
+	intc_irqpin_dbg(&p->irq[hw_irq], "shared disable");
+	intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq);
+
+	p->shared_irq_mask |= BIT(hw_irq);
+}
+
+static void intc_irqpin_irq_enable_force(struct irq_data *d)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+	int irq = p->irq[irqd_to_hwirq(d)].requested_irq;
+
+	intc_irqpin_irq_enable(d);
+
+	/* enable interrupt through parent interrupt controller,
+	 * assumes non-shared interrupt with 1:1 mapping
+	 * needed for busted IRQs on some SoCs like sh73a0
+	 */
+	irq_get_chip(irq)->irq_unmask(irq_get_irq_data(irq));
+}
+
+static void intc_irqpin_irq_disable_force(struct irq_data *d)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+	int irq = p->irq[irqd_to_hwirq(d)].requested_irq;
+
+	/* disable interrupt through parent interrupt controller,
+	 * assumes non-shared interrupt with 1:1 mapping
+	 * needed for busted IRQs on some SoCs like sh73a0
+	 */
+	irq_get_chip(irq)->irq_mask(irq_get_irq_data(irq));
+	intc_irqpin_irq_disable(d);
+}
+
+#define INTC_IRQ_SENSE_VALID 0x10
+#define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID)
+
+static unsigned char intc_irqpin_sense[IRQ_TYPE_SENSE_MASK + 1] = {
+	[IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x00),
+	[IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x01),
+	[IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x02),
+	[IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x03),
+	[IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x04),
+};
+
+static int intc_irqpin_irq_set_type(struct irq_data *d, unsigned int type)
+{
+	unsigned char value = intc_irqpin_sense[type & IRQ_TYPE_SENSE_MASK];
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+
+	if (!(value & INTC_IRQ_SENSE_VALID))
+		return -EINVAL;
+
+	return intc_irqpin_set_sense(p, irqd_to_hwirq(d),
+				     value ^ INTC_IRQ_SENSE_VALID);
+}
+
+static int intc_irqpin_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+	struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d);
+
+	if (!p->clk)
+		return 0;
+
+	if (on)
+		clk_enable(p->clk);
+	else
+		clk_disable(p->clk);
+
+	return 0;
+}
+
+static irqreturn_t intc_irqpin_irq_handler(int irq, void *dev_id)
+{
+	struct intc_irqpin_irq *i = dev_id;
+	struct intc_irqpin_priv *p = i->p;
+	unsigned long bit;
+
+	intc_irqpin_dbg(i, "demux1");
+	bit = intc_irqpin_hwirq_mask(p, INTC_IRQPIN_REG_SOURCE, i->hw_irq);
+
+	if (intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE) & bit) {
+		intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, ~bit);
+		intc_irqpin_dbg(i, "demux2");
+		generic_handle_irq(i->domain_irq);
+		return IRQ_HANDLED;
+	}
+	return IRQ_NONE;
+}
+
+static irqreturn_t intc_irqpin_shared_irq_handler(int irq, void *dev_id)
+{
+	struct intc_irqpin_priv *p = dev_id;
+	unsigned int reg_source = intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE);
+	irqreturn_t status = IRQ_NONE;
+	int k;
+
+	for (k = 0; k < 8; k++) {
+		if (reg_source & BIT(7 - k)) {
+			if (BIT(k) & p->shared_irq_mask)
+				continue;
+
+			status |= intc_irqpin_irq_handler(irq, &p->irq[k]);
+		}
+	}
+
+	return status;
+}
+
+static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq,
+				      irq_hw_number_t hw)
+{
+	struct intc_irqpin_priv *p = h->host_data;
+
+	p->irq[hw].domain_irq = virq;
+	p->irq[hw].hw_irq = hw;
+
+	intc_irqpin_dbg(&p->irq[hw], "map");
+	irq_set_chip_data(virq, h->host_data);
+	irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
+	set_irq_flags(virq, IRQF_VALID); /* kill me now */
+	return 0;
+}
+
+static struct irq_domain_ops intc_irqpin_irq_domain_ops = {
+	.map	= intc_irqpin_irq_domain_map,
+	.xlate  = irq_domain_xlate_twocell,
+};
+
+static const struct intc_irqpin_irlm_config intc_irqpin_irlm_r8a7779 = {
+	.irlm_bit = 23, /* ICR0.IRLM0 */
+};
+
+static const struct of_device_id intc_irqpin_dt_ids[] = {
+	{ .compatible = "renesas,intc-irqpin", },
+	{ .compatible = "renesas,intc-irqpin-r8a7779",
+	  .data = &intc_irqpin_irlm_r8a7779 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, intc_irqpin_dt_ids);
+
+static int intc_irqpin_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct renesas_intc_irqpin_config *pdata = dev->platform_data;
+	const struct of_device_id *of_id;
+	struct intc_irqpin_priv *p;
+	struct intc_irqpin_iomem *i;
+	struct resource *io[INTC_IRQPIN_REG_NR];
+	struct resource *irq;
+	struct irq_chip *irq_chip;
+	void (*enable_fn)(struct irq_data *d);
+	void (*disable_fn)(struct irq_data *d);
+	const char *name = dev_name(dev);
+	int ref_irq;
+	int ret;
+	int k;
+
+	p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
+	if (!p) {
+		dev_err(dev, "failed to allocate driver data\n");
+		return -ENOMEM;
+	}
+
+	/* deal with driver instance configuration */
+	if (pdata) {
+		memcpy(&p->config, pdata, sizeof(*pdata));
+	} else {
+		of_property_read_u32(dev->of_node, "sense-bitfield-width",
+				     &p->config.sense_bitfield_width);
+		p->config.control_parent = of_property_read_bool(dev->of_node,
+								 "control-parent");
+	}
+	if (!p->config.sense_bitfield_width)
+		p->config.sense_bitfield_width = 4; /* default to 4 bits */
+
+	p->pdev = pdev;
+	platform_set_drvdata(pdev, p);
+
+	p->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(p->clk)) {
+		dev_warn(dev, "unable to get clock\n");
+		p->clk = NULL;
+	}
+
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+
+	/* get hold of register banks */
+	memset(io, 0, sizeof(io));
+	for (k = 0; k < INTC_IRQPIN_REG_NR; k++) {
+		io[k] = platform_get_resource(pdev, IORESOURCE_MEM, k);
+		if (!io[k] && k < INTC_IRQPIN_REG_NR_MANDATORY) {
+			dev_err(dev, "not enough IOMEM resources\n");
+			ret = -EINVAL;
+			goto err0;
+		}
+	}
+
+	/* allow any number of IRQs between 1 and INTC_IRQPIN_MAX */
+	for (k = 0; k < INTC_IRQPIN_MAX; k++) {
+		irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
+		if (!irq)
+			break;
+
+		p->irq[k].p = p;
+		p->irq[k].requested_irq = irq->start;
+	}
+
+	p->number_of_irqs = k;
+	if (p->number_of_irqs < 1) {
+		dev_err(dev, "not enough IRQ resources\n");
+		ret = -EINVAL;
+		goto err0;
+	}
+
+	/* ioremap IOMEM and setup read/write callbacks */
+	for (k = 0; k < INTC_IRQPIN_REG_NR; k++) {
+		i = &p->iomem[k];
+
+		/* handle optional registers */
+		if (!io[k])
+			continue;
+
+		switch (resource_size(io[k])) {
+		case 1:
+			i->width = 8;
+			i->read = intc_irqpin_read8;
+			i->write = intc_irqpin_write8;
+			break;
+		case 4:
+			i->width = 32;
+			i->read = intc_irqpin_read32;
+			i->write = intc_irqpin_write32;
+			break;
+		default:
+			dev_err(dev, "IOMEM size mismatch\n");
+			ret = -EINVAL;
+			goto err0;
+		}
+
+		i->iomem = devm_ioremap_nocache(dev, io[k]->start,
+						resource_size(io[k]));
+		if (!i->iomem) {
+			dev_err(dev, "failed to remap IOMEM\n");
+			ret = -ENXIO;
+			goto err0;
+		}
+	}
+
+	/* configure "individual IRQ mode" where needed */
+	of_id = of_match_device(intc_irqpin_dt_ids, dev);
+	if (of_id && of_id->data) {
+		const struct intc_irqpin_irlm_config *irlm_config = of_id->data;
+
+		if (io[INTC_IRQPIN_REG_IRLM])
+			intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_IRLM,
+						      irlm_config->irlm_bit,
+						      1, 1);
+		else
+			dev_warn(dev, "unable to select IRLM mode\n");
+	}
+
+	/* mask all interrupts using priority */
+	for (k = 0; k < p->number_of_irqs; k++)
+		intc_irqpin_mask_unmask_prio(p, k, 1);
+
+	/* clear all pending interrupts */
+	intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, 0x0);
+
+	/* scan for shared interrupt lines */
+	ref_irq = p->irq[0].requested_irq;
+	p->shared_irqs = true;
+	for (k = 1; k < p->number_of_irqs; k++) {
+		if (ref_irq != p->irq[k].requested_irq) {
+			p->shared_irqs = false;
+			break;
+		}
+	}
+
+	/* use more severe masking method if requested */
+	if (p->config.control_parent) {
+		enable_fn = intc_irqpin_irq_enable_force;
+		disable_fn = intc_irqpin_irq_disable_force;
+	} else if (!p->shared_irqs) {
+		enable_fn = intc_irqpin_irq_enable;
+		disable_fn = intc_irqpin_irq_disable;
+	} else {
+		enable_fn = intc_irqpin_shared_irq_enable;
+		disable_fn = intc_irqpin_shared_irq_disable;
+	}
+
+	irq_chip = &p->irq_chip;
+	irq_chip->name = name;
+	irq_chip->irq_mask = disable_fn;
+	irq_chip->irq_unmask = enable_fn;
+	irq_chip->irq_set_type = intc_irqpin_irq_set_type;
+	irq_chip->irq_set_wake = intc_irqpin_irq_set_wake;
+	irq_chip->flags	= IRQCHIP_MASK_ON_SUSPEND;
+
+	p->irq_domain = irq_domain_add_simple(dev->of_node,
+					      p->number_of_irqs,
+					      p->config.irq_base,
+					      &intc_irqpin_irq_domain_ops, p);
+	if (!p->irq_domain) {
+		ret = -ENXIO;
+		dev_err(dev, "cannot initialize irq domain\n");
+		goto err0;
+	}
+
+	if (p->shared_irqs) {
+		/* request one shared interrupt */
+		if (devm_request_irq(dev, p->irq[0].requested_irq,
+				intc_irqpin_shared_irq_handler,
+				IRQF_SHARED, name, p)) {
+			dev_err(dev, "failed to request low IRQ\n");
+			ret = -ENOENT;
+			goto err1;
+		}
+	} else {
+		/* request interrupts one by one */
+		for (k = 0; k < p->number_of_irqs; k++) {
+			if (devm_request_irq(dev, p->irq[k].requested_irq,
+					     intc_irqpin_irq_handler, 0, name,
+					     &p->irq[k])) {
+				dev_err(dev, "failed to request low IRQ\n");
+				ret = -ENOENT;
+				goto err1;
+			}
+		}
+	}
+
+	/* unmask all interrupts on prio level */
+	for (k = 0; k < p->number_of_irqs; k++)
+		intc_irqpin_mask_unmask_prio(p, k, 0);
+
+	dev_info(dev, "driving %d irqs\n", p->number_of_irqs);
+
+	/* warn in case of mismatch if irq base is specified */
+	if (p->config.irq_base) {
+		if (p->config.irq_base != p->irq[0].domain_irq)
+			dev_warn(dev, "irq base mismatch (%d/%d)\n",
+				 p->config.irq_base, p->irq[0].domain_irq);
+	}
+
+	return 0;
+
+err1:
+	irq_domain_remove(p->irq_domain);
+err0:
+	pm_runtime_put(dev);
+	pm_runtime_disable(dev);
+	return ret;
+}
+
+static int intc_irqpin_remove(struct platform_device *pdev)
+{
+	struct intc_irqpin_priv *p = platform_get_drvdata(pdev);
+
+	irq_domain_remove(p->irq_domain);
+	pm_runtime_put(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	return 0;
+}
+
+static struct platform_driver intc_irqpin_device_driver = {
+	.probe		= intc_irqpin_probe,
+	.remove		= intc_irqpin_remove,
+	.driver		= {
+		.name	= "renesas_intc_irqpin",
+		.of_match_table = intc_irqpin_dt_ids,
+	}
+};
+
+static int __init intc_irqpin_init(void)
+{
+	return platform_driver_register(&intc_irqpin_device_driver);
+}
+postcore_initcall(intc_irqpin_init);
+
+static void __exit intc_irqpin_exit(void)
+{
+	platform_driver_unregister(&intc_irqpin_device_driver);
+}
+module_exit(intc_irqpin_exit);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("Renesas INTC External IRQ Pin Driver");
+MODULE_LICENSE("GPL v2");