1 files changed, 490 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-imgpdc.c b/drivers/irqchip/irq-imgpdc.c
new file mode 100644
index 000000000..5831be454
--- /dev/null
+++ b/drivers/irqchip/irq-imgpdc.c
@@ -0,0 +1,490 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IMG PowerDown Controller (PDC)
+ *
+ * Copyright 2010-2013 Imagination Technologies Ltd.
+ *
+ * Exposes the syswake and PDC peripheral wake interrupts to the system.
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+/* PDC interrupt register numbers */
+
+#define PDC_IRQ_STATUS			0x310
+#define PDC_IRQ_ENABLE			0x314
+#define PDC_IRQ_CLEAR			0x318
+#define PDC_IRQ_ROUTE			0x31c
+#define PDC_SYS_WAKE_BASE		0x330
+#define PDC_SYS_WAKE_STRIDE		0x8
+#define PDC_SYS_WAKE_CONFIG_BASE	0x334
+#define PDC_SYS_WAKE_CONFIG_STRIDE	0x8
+
+/* PDC interrupt register field masks */
+
+#define PDC_IRQ_SYS3			0x08
+#define PDC_IRQ_SYS2			0x04
+#define PDC_IRQ_SYS1			0x02
+#define PDC_IRQ_SYS0			0x01
+#define PDC_IRQ_ROUTE_WU_EN_SYS3	0x08000000
+#define PDC_IRQ_ROUTE_WU_EN_SYS2	0x04000000
+#define PDC_IRQ_ROUTE_WU_EN_SYS1	0x02000000
+#define PDC_IRQ_ROUTE_WU_EN_SYS0	0x01000000
+#define PDC_IRQ_ROUTE_WU_EN_WD		0x00040000
+#define PDC_IRQ_ROUTE_WU_EN_IR		0x00020000
+#define PDC_IRQ_ROUTE_WU_EN_RTC		0x00010000
+#define PDC_IRQ_ROUTE_EXT_EN_SYS3	0x00000800
+#define PDC_IRQ_ROUTE_EXT_EN_SYS2	0x00000400
+#define PDC_IRQ_ROUTE_EXT_EN_SYS1	0x00000200
+#define PDC_IRQ_ROUTE_EXT_EN_SYS0	0x00000100
+#define PDC_IRQ_ROUTE_EXT_EN_WD		0x00000004
+#define PDC_IRQ_ROUTE_EXT_EN_IR		0x00000002
+#define PDC_IRQ_ROUTE_EXT_EN_RTC	0x00000001
+#define PDC_SYS_WAKE_RESET		0x00000010
+#define PDC_SYS_WAKE_INT_MODE		0x0000000e
+#define PDC_SYS_WAKE_INT_MODE_SHIFT	1
+#define PDC_SYS_WAKE_PIN_VAL		0x00000001
+
+/* PDC interrupt constants */
+
+#define PDC_SYS_WAKE_INT_LOW		0x0
+#define PDC_SYS_WAKE_INT_HIGH		0x1
+#define PDC_SYS_WAKE_INT_DOWN		0x2
+#define PDC_SYS_WAKE_INT_UP		0x3
+#define PDC_SYS_WAKE_INT_CHANGE		0x6
+#define PDC_SYS_WAKE_INT_NONE		0x4
+
+/**
+ * struct pdc_intc_priv - private pdc interrupt data.
+ * @nr_perips:		Number of peripheral interrupt signals.
+ * @nr_syswakes:	Number of syswake signals.
+ * @perip_irqs:		List of peripheral IRQ numbers handled.
+ * @syswake_irq:	Shared PDC syswake IRQ number.
+ * @domain:		IRQ domain for PDC peripheral and syswake IRQs.
+ * @pdc_base:		Base of PDC registers.
+ * @irq_route:		Cached version of PDC_IRQ_ROUTE register.
+ * @lock:		Lock to protect the PDC syswake registers and the cached
+ *			values of those registers in this struct.
+ */
+struct pdc_intc_priv {
+	unsigned int		nr_perips;
+	unsigned int		nr_syswakes;
+	unsigned int		*perip_irqs;
+	unsigned int		syswake_irq;
+	struct irq_domain	*domain;
+	void __iomem		*pdc_base;
+
+	u32			irq_route;
+	raw_spinlock_t		lock;
+};
+
+static void pdc_write(struct pdc_intc_priv *priv, unsigned int reg_offs,
+		      unsigned int data)
+{
+	iowrite32(data, priv->pdc_base + reg_offs);
+}
+
+static unsigned int pdc_read(struct pdc_intc_priv *priv,
+			     unsigned int reg_offs)
+{
+	return ioread32(priv->pdc_base + reg_offs);
+}
+
+/* Generic IRQ callbacks */
+
+#define SYS0_HWIRQ	8
+
+static unsigned int hwirq_is_syswake(irq_hw_number_t hw)
+{
+	return hw >= SYS0_HWIRQ;
+}
+
+static unsigned int hwirq_to_syswake(irq_hw_number_t hw)
+{
+	return hw - SYS0_HWIRQ;
+}
+
+static irq_hw_number_t syswake_to_hwirq(unsigned int syswake)
+{
+	return SYS0_HWIRQ + syswake;
+}
+
+static struct pdc_intc_priv *irqd_to_priv(struct irq_data *data)
+{
+	return (struct pdc_intc_priv *)data->domain->host_data;
+}
+
+/*
+ * perip_irq_mask() and perip_irq_unmask() use IRQ_ROUTE which also contains
+ * wake bits, therefore we cannot use the generic irqchip mask callbacks as they
+ * cache the mask.
+ */
+
+static void perip_irq_mask(struct irq_data *data)
+{
+	struct pdc_intc_priv *priv = irqd_to_priv(data);
+
+	raw_spin_lock(&priv->lock);
+	priv->irq_route &= ~data->mask;
+	pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+	raw_spin_unlock(&priv->lock);
+}
+
+static void perip_irq_unmask(struct irq_data *data)
+{
+	struct pdc_intc_priv *priv = irqd_to_priv(data);
+
+	raw_spin_lock(&priv->lock);
+	priv->irq_route |= data->mask;
+	pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+	raw_spin_unlock(&priv->lock);
+}
+
+static int syswake_irq_set_type(struct irq_data *data, unsigned int flow_type)
+{
+	struct pdc_intc_priv *priv = irqd_to_priv(data);
+	unsigned int syswake = hwirq_to_syswake(data->hwirq);
+	unsigned int irq_mode;
+	unsigned int soc_sys_wake_regoff, soc_sys_wake;
+
+	/* translate to syswake IRQ mode */
+	switch (flow_type) {
+	case IRQ_TYPE_EDGE_BOTH:
+		irq_mode = PDC_SYS_WAKE_INT_CHANGE;
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		irq_mode = PDC_SYS_WAKE_INT_UP;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		irq_mode = PDC_SYS_WAKE_INT_DOWN;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		irq_mode = PDC_SYS_WAKE_INT_HIGH;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		irq_mode = PDC_SYS_WAKE_INT_LOW;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	raw_spin_lock(&priv->lock);
+
+	/* set the IRQ mode */
+	soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + syswake*PDC_SYS_WAKE_STRIDE;
+	soc_sys_wake = pdc_read(priv, soc_sys_wake_regoff);
+	soc_sys_wake &= ~PDC_SYS_WAKE_INT_MODE;
+	soc_sys_wake |= irq_mode << PDC_SYS_WAKE_INT_MODE_SHIFT;
+	pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
+
+	/* and update the handler */
+	irq_setup_alt_chip(data, flow_type);
+
+	raw_spin_unlock(&priv->lock);
+
+	return 0;
+}
+
+/* applies to both peripheral and syswake interrupts */
+static int pdc_irq_set_wake(struct irq_data *data, unsigned int on)
+{
+	struct pdc_intc_priv *priv = irqd_to_priv(data);
+	irq_hw_number_t hw = data->hwirq;
+	unsigned int mask = (1 << 16) << hw;
+	unsigned int dst_irq;
+
+	raw_spin_lock(&priv->lock);
+	if (on)
+		priv->irq_route |= mask;
+	else
+		priv->irq_route &= ~mask;
+	pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+	raw_spin_unlock(&priv->lock);
+
+	/* control the destination IRQ wakeup too for standby mode */
+	if (hwirq_is_syswake(hw))
+		dst_irq = priv->syswake_irq;
+	else
+		dst_irq = priv->perip_irqs[hw];
+	irq_set_irq_wake(dst_irq, on);
+
+	return 0;
+}
+
+static void pdc_intc_perip_isr(struct irq_desc *desc)
+{
+	unsigned int irq = irq_desc_get_irq(desc);
+	struct pdc_intc_priv *priv;
+	unsigned int i;
+
+	priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
+
+	/* find the peripheral number */
+	for (i = 0; i < priv->nr_perips; ++i)
+		if (irq == priv->perip_irqs[i])
+			goto found;
+
+	/* should never get here */
+	return;
+found:
+
+	/* pass on the interrupt */
+	generic_handle_domain_irq(priv->domain, i);
+}
+
+static void pdc_intc_syswake_isr(struct irq_desc *desc)
+{
+	struct pdc_intc_priv *priv;
+	unsigned int syswake;
+	unsigned int status;
+
+	priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
+
+	status = pdc_read(priv, PDC_IRQ_STATUS) &
+		 pdc_read(priv, PDC_IRQ_ENABLE);
+	status &= (1 << priv->nr_syswakes) - 1;
+
+	for (syswake = 0; status; status >>= 1, ++syswake) {
+		/* Has this sys_wake triggered? */
+		if (!(status & 1))
+			continue;
+
+		generic_handle_domain_irq(priv->domain, syswake_to_hwirq(syswake));
+	}
+}
+
+static void pdc_intc_setup(struct pdc_intc_priv *priv)
+{
+	int i;
+	unsigned int soc_sys_wake_regoff;
+	unsigned int soc_sys_wake;
+
+	/*
+	 * Mask all syswake interrupts before routing, or we could receive an
+	 * interrupt before we're ready to handle it.
+	 */
+	pdc_write(priv, PDC_IRQ_ENABLE, 0);
+
+	/*
+	 * Enable routing of all syswakes
+	 * Disable all wake sources
+	 */
+	priv->irq_route = ((PDC_IRQ_ROUTE_EXT_EN_SYS0 << priv->nr_syswakes) -
+				PDC_IRQ_ROUTE_EXT_EN_SYS0);
+	pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+
+	/* Initialise syswake IRQ */
+	for (i = 0; i < priv->nr_syswakes; ++i) {
+		/* set the IRQ mode to none */
+		soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + i*PDC_SYS_WAKE_STRIDE;
+		soc_sys_wake = PDC_SYS_WAKE_INT_NONE
+				<< PDC_SYS_WAKE_INT_MODE_SHIFT;
+		pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
+	}
+}
+
+static int pdc_intc_probe(struct platform_device *pdev)
+{
+	struct pdc_intc_priv *priv;
+	struct device_node *node = pdev->dev.of_node;
+	struct resource *res_regs;
+	struct irq_chip_generic *gc;
+	unsigned int i;
+	int irq, ret;
+	u32 val;
+
+	if (!node)
+		return -ENOENT;
+
+	/* Get registers */
+	res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res_regs == NULL) {
+		dev_err(&pdev->dev, "cannot find registers resource\n");
+		return -ENOENT;
+	}
+
+	/* Allocate driver data */
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+	raw_spin_lock_init(&priv->lock);
+	platform_set_drvdata(pdev, priv);
+
+	/* Ioremap the registers */
+	priv->pdc_base = devm_ioremap(&pdev->dev, res_regs->start,
+				      resource_size(res_regs));
+	if (!priv->pdc_base)
+		return -EIO;
+
+	/* Get number of peripherals */
+	ret = of_property_read_u32(node, "num-perips", &val);
+	if (ret) {
+		dev_err(&pdev->dev, "No num-perips node property found\n");
+		return -EINVAL;
+	}
+	if (val > SYS0_HWIRQ) {
+		dev_err(&pdev->dev, "num-perips (%u) out of range\n", val);
+		return -EINVAL;
+	}
+	priv->nr_perips = val;
+
+	/* Get number of syswakes */
+	ret = of_property_read_u32(node, "num-syswakes", &val);
+	if (ret) {
+		dev_err(&pdev->dev, "No num-syswakes node property found\n");
+		return -EINVAL;
+	}
+	if (val > SYS0_HWIRQ) {
+		dev_err(&pdev->dev, "num-syswakes (%u) out of range\n", val);
+		return -EINVAL;
+	}
+	priv->nr_syswakes = val;
+
+	/* Get peripheral IRQ numbers */
+	priv->perip_irqs = devm_kcalloc(&pdev->dev, 4, priv->nr_perips,
+					GFP_KERNEL);
+	if (!priv->perip_irqs)
+		return -ENOMEM;
+	for (i = 0; i < priv->nr_perips; ++i) {
+		irq = platform_get_irq(pdev, 1 + i);
+		if (irq < 0)
+			return irq;
+		priv->perip_irqs[i] = irq;
+	}
+	/* check if too many were provided */
+	if (platform_get_irq(pdev, 1 + i) >= 0) {
+		dev_err(&pdev->dev, "surplus perip IRQs detected\n");
+		return -EINVAL;
+	}
+
+	/* Get syswake IRQ number */
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+	priv->syswake_irq = irq;
+
+	/* Set up an IRQ domain */
+	priv->domain = irq_domain_add_linear(node, 16, &irq_generic_chip_ops,
+					     priv);
+	if (unlikely(!priv->domain)) {
+		dev_err(&pdev->dev, "cannot add IRQ domain\n");
+		return -ENOMEM;
+	}
+
+	/*
+	 * Set up 2 generic irq chips with 2 chip types.
+	 * The first one for peripheral irqs (only 1 chip type used)
+	 * The second one for syswake irqs (edge and level chip types)
+	 */
+	ret = irq_alloc_domain_generic_chips(priv->domain, 8, 2, "pdc",
+					     handle_level_irq, 0, 0,
+					     IRQ_GC_INIT_NESTED_LOCK);
+	if (ret)
+		goto err_generic;
+
+	/* peripheral interrupt chip */
+
+	gc = irq_get_domain_generic_chip(priv->domain, 0);
+	gc->unused	= ~(BIT(priv->nr_perips) - 1);
+	gc->reg_base	= priv->pdc_base;
+	/*
+	 * IRQ_ROUTE contains wake bits, so we can't use the generic versions as
+	 * they cache the mask
+	 */
+	gc->chip_types[0].regs.mask		= PDC_IRQ_ROUTE;
+	gc->chip_types[0].chip.irq_mask		= perip_irq_mask;
+	gc->chip_types[0].chip.irq_unmask	= perip_irq_unmask;
+	gc->chip_types[0].chip.irq_set_wake	= pdc_irq_set_wake;
+
+	/* syswake interrupt chip */
+
+	gc = irq_get_domain_generic_chip(priv->domain, 8);
+	gc->unused	= ~(BIT(priv->nr_syswakes) - 1);
+	gc->reg_base	= priv->pdc_base;
+
+	/* edge interrupts */
+	gc->chip_types[0].type			= IRQ_TYPE_EDGE_BOTH;
+	gc->chip_types[0].handler		= handle_edge_irq;
+	gc->chip_types[0].regs.ack		= PDC_IRQ_CLEAR;
+	gc->chip_types[0].regs.mask		= PDC_IRQ_ENABLE;
+	gc->chip_types[0].chip.irq_ack		= irq_gc_ack_set_bit;
+	gc->chip_types[0].chip.irq_mask		= irq_gc_mask_clr_bit;
+	gc->chip_types[0].chip.irq_unmask	= irq_gc_mask_set_bit;
+	gc->chip_types[0].chip.irq_set_type	= syswake_irq_set_type;
+	gc->chip_types[0].chip.irq_set_wake	= pdc_irq_set_wake;
+	/* for standby we pass on to the shared syswake IRQ */
+	gc->chip_types[0].chip.flags		= IRQCHIP_MASK_ON_SUSPEND;
+
+	/* level interrupts */
+	gc->chip_types[1].type			= IRQ_TYPE_LEVEL_MASK;
+	gc->chip_types[1].handler		= handle_level_irq;
+	gc->chip_types[1].regs.ack		= PDC_IRQ_CLEAR;
+	gc->chip_types[1].regs.mask		= PDC_IRQ_ENABLE;
+	gc->chip_types[1].chip.irq_ack		= irq_gc_ack_set_bit;
+	gc->chip_types[1].chip.irq_mask		= irq_gc_mask_clr_bit;
+	gc->chip_types[1].chip.irq_unmask	= irq_gc_mask_set_bit;
+	gc->chip_types[1].chip.irq_set_type	= syswake_irq_set_type;
+	gc->chip_types[1].chip.irq_set_wake	= pdc_irq_set_wake;
+	/* for standby we pass on to the shared syswake IRQ */
+	gc->chip_types[1].chip.flags		= IRQCHIP_MASK_ON_SUSPEND;
+
+	/* Set up the hardware to enable interrupt routing */
+	pdc_intc_setup(priv);
+
+	/* Setup chained handlers for the peripheral IRQs */
+	for (i = 0; i < priv->nr_perips; ++i) {
+		irq = priv->perip_irqs[i];
+		irq_set_chained_handler_and_data(irq, pdc_intc_perip_isr,
+						 priv);
+	}
+
+	/* Setup chained handler for the syswake IRQ */
+	irq_set_chained_handler_and_data(priv->syswake_irq,
+					 pdc_intc_syswake_isr, priv);
+
+	dev_info(&pdev->dev,
+		 "PDC IRQ controller initialised (%u perip IRQs, %u syswake IRQs)\n",
+		 priv->nr_perips,
+		 priv->nr_syswakes);
+
+	return 0;
+err_generic:
+	irq_domain_remove(priv->domain);
+	return ret;
+}
+
+static int pdc_intc_remove(struct platform_device *pdev)
+{
+	struct pdc_intc_priv *priv = platform_get_drvdata(pdev);
+
+	irq_domain_remove(priv->domain);
+	return 0;
+}
+
+static const struct of_device_id pdc_intc_match[] = {
+	{ .compatible = "img,pdc-intc" },
+	{}
+};
+
+static struct platform_driver pdc_intc_driver = {
+	.driver = {
+		.name		= "pdc-intc",
+		.of_match_table	= pdc_intc_match,
+	},
+	.probe = pdc_intc_probe,
+	.remove = pdc_intc_remove,
+};
+
+static int __init pdc_intc_init(void)
+{
+	return platform_driver_register(&pdc_intc_driver);
+}
+core_initcall(pdc_intc_init);