irqchip: Move ARM VIC to drivers/irqchip

Now that we have drivers/irqchip, move VIC irqchip to drivers/irqchip.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 489 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-vic.c b/drivers/irqchip/irq-vic.c
new file mode 100644
index 0000000..e9a8a7d
--- /dev/null
+++ b/drivers/irqchip/irq-vic.c
@@ -0,0 +1,489 @@
+/*
+ *  linux/arch/arm/common/vic.c
+ *
+ *  Copyright (C) 1999 - 2003 ARM Limited
+ *  Copyright (C) 2000 Deep Blue Solutions Ltd
+ *
+ * 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, or
+ * (at your option) any later version.
+ *
+ * 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/export.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/syscore_ops.h>
+#include <linux/device.h>
+#include <linux/amba/bus.h>
+
+#include <asm/exception.h>
+#include <asm/mach/irq.h>
+#include <asm/hardware/vic.h>
+
+#include "irqchip.h"
+
+#define VIC_IRQ_STATUS			0x00
+#define VIC_FIQ_STATUS			0x04
+#define VIC_INT_SELECT			0x0c	/* 1 = FIQ, 0 = IRQ */
+#define VIC_INT_SOFT			0x18
+#define VIC_INT_SOFT_CLEAR		0x1c
+#define VIC_PROTECT			0x20
+#define VIC_PL190_VECT_ADDR		0x30	/* PL190 only */
+#define VIC_PL190_DEF_VECT_ADDR		0x34	/* PL190 only */
+
+#define VIC_VECT_ADDR0			0x100	/* 0 to 15 (0..31 PL192) */
+#define VIC_VECT_CNTL0			0x200	/* 0 to 15 (0..31 PL192) */
+#define VIC_ITCR			0x300	/* VIC test control register */
+
+#define VIC_VECT_CNTL_ENABLE		(1 << 5)
+
+#define VIC_PL192_VECT_ADDR		0xF00
+
+/**
+ * struct vic_device - VIC PM device
+ * @irq: The IRQ number for the base of the VIC.
+ * @base: The register base for the VIC.
+ * @valid_sources: A bitmask of valid interrupts
+ * @resume_sources: A bitmask of interrupts for resume.
+ * @resume_irqs: The IRQs enabled for resume.
+ * @int_select: Save for VIC_INT_SELECT.
+ * @int_enable: Save for VIC_INT_ENABLE.
+ * @soft_int: Save for VIC_INT_SOFT.
+ * @protect: Save for VIC_PROTECT.
+ * @domain: The IRQ domain for the VIC.
+ */
+struct vic_device {
+	void __iomem	*base;
+	int		irq;
+	u32		valid_sources;
+	u32		resume_sources;
+	u32		resume_irqs;
+	u32		int_select;
+	u32		int_enable;
+	u32		soft_int;
+	u32		protect;
+	struct irq_domain *domain;
+};
+
+/* we cannot allocate memory when VICs are initially registered */
+static struct vic_device vic_devices[CONFIG_ARM_VIC_NR];
+
+static int vic_id;
+
+static void vic_handle_irq(struct pt_regs *regs);
+
+/**
+ * vic_init2 - common initialisation code
+ * @base: Base of the VIC.
+ *
+ * Common initialisation code for registration
+ * and resume.
+*/
+static void vic_init2(void __iomem *base)
+{
+	int i;
+
+	for (i = 0; i < 16; i++) {
+		void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4);
+		writel(VIC_VECT_CNTL_ENABLE | i, reg);
+	}
+
+	writel(32, base + VIC_PL190_DEF_VECT_ADDR);
+}
+
+#ifdef CONFIG_PM
+static void resume_one_vic(struct vic_device *vic)
+{
+	void __iomem *base = vic->base;
+
+	printk(KERN_DEBUG "%s: resuming vic at %p\n", __func__, base);
+
+	/* re-initialise static settings */
+	vic_init2(base);
+
+	writel(vic->int_select, base + VIC_INT_SELECT);
+	writel(vic->protect, base + VIC_PROTECT);
+
+	/* set the enabled ints and then clear the non-enabled */
+	writel(vic->int_enable, base + VIC_INT_ENABLE);
+	writel(~vic->int_enable, base + VIC_INT_ENABLE_CLEAR);
+
+	/* and the same for the soft-int register */
+
+	writel(vic->soft_int, base + VIC_INT_SOFT);
+	writel(~vic->soft_int, base + VIC_INT_SOFT_CLEAR);
+}
+
+static void vic_resume(void)
+{
+	int id;
+
+	for (id = vic_id - 1; id >= 0; id--)
+		resume_one_vic(vic_devices + id);
+}
+
+static void suspend_one_vic(struct vic_device *vic)
+{
+	void __iomem *base = vic->base;
+
+	printk(KERN_DEBUG "%s: suspending vic at %p\n", __func__, base);
+
+	vic->int_select = readl(base + VIC_INT_SELECT);
+	vic->int_enable = readl(base + VIC_INT_ENABLE);
+	vic->soft_int = readl(base + VIC_INT_SOFT);
+	vic->protect = readl(base + VIC_PROTECT);
+
+	/* set the interrupts (if any) that are used for
+	 * resuming the system */
+
+	writel(vic->resume_irqs, base + VIC_INT_ENABLE);
+	writel(~vic->resume_irqs, base + VIC_INT_ENABLE_CLEAR);
+}
+
+static int vic_suspend(void)
+{
+	int id;
+
+	for (id = 0; id < vic_id; id++)
+		suspend_one_vic(vic_devices + id);
+
+	return 0;
+}
+
+struct syscore_ops vic_syscore_ops = {
+	.suspend	= vic_suspend,
+	.resume		= vic_resume,
+};
+
+/**
+ * vic_pm_init - initicall to register VIC pm
+ *
+ * This is called via late_initcall() to register
+ * the resources for the VICs due to the early
+ * nature of the VIC's registration.
+*/
+static int __init vic_pm_init(void)
+{
+	if (vic_id > 0)
+		register_syscore_ops(&vic_syscore_ops);
+
+	return 0;
+}
+late_initcall(vic_pm_init);
+#endif /* CONFIG_PM */
+
+static struct irq_chip vic_chip;
+
+static int vic_irqdomain_map(struct irq_domain *d, unsigned int irq,
+			     irq_hw_number_t hwirq)
+{
+	struct vic_device *v = d->host_data;
+
+	/* Skip invalid IRQs, only register handlers for the real ones */
+	if (!(v->valid_sources & (1 << hwirq)))
+		return -ENOTSUPP;
+	irq_set_chip_and_handler(irq, &vic_chip, handle_level_irq);
+	irq_set_chip_data(irq, v->base);
+	set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+	return 0;
+}
+
+/*
+ * Handle each interrupt in a single VIC.  Returns non-zero if we've
+ * handled at least one interrupt.  This reads the status register
+ * before handling each interrupt, which is necessary given that
+ * handle_IRQ may briefly re-enable interrupts for soft IRQ handling.
+ */
+static int handle_one_vic(struct vic_device *vic, struct pt_regs *regs)
+{
+	u32 stat, irq;
+	int handled = 0;
+
+	while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) {
+		irq = ffs(stat) - 1;
+		handle_IRQ(irq_find_mapping(vic->domain, irq), regs);
+		handled = 1;
+	}
+
+	return handled;
+}
+
+/*
+ * Keep iterating over all registered VIC's until there are no pending
+ * interrupts.
+ */
+static asmlinkage void __exception_irq_entry vic_handle_irq(struct pt_regs *regs)
+{
+	int i, handled;
+
+	do {
+		for (i = 0, handled = 0; i < vic_id; ++i)
+			handled |= handle_one_vic(&vic_devices[i], regs);
+	} while (handled);
+}
+
+static struct irq_domain_ops vic_irqdomain_ops = {
+	.map = vic_irqdomain_map,
+	.xlate = irq_domain_xlate_onetwocell,
+};
+
+/**
+ * vic_register() - Register a VIC.
+ * @base: The base address of the VIC.
+ * @irq: The base IRQ for the VIC.
+ * @valid_sources: bitmask of valid interrupts
+ * @resume_sources: bitmask of interrupts allowed for resume sources.
+ * @node: The device tree node associated with the VIC.
+ *
+ * Register the VIC with the system device tree so that it can be notified
+ * of suspend and resume requests and ensure that the correct actions are
+ * taken to re-instate the settings on resume.
+ *
+ * This also configures the IRQ domain for the VIC.
+ */
+static void __init vic_register(void __iomem *base, unsigned int irq,
+				u32 valid_sources, u32 resume_sources,
+				struct device_node *node)
+{
+	struct vic_device *v;
+	int i;
+
+	if (vic_id >= ARRAY_SIZE(vic_devices)) {
+		printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__);
+		return;
+	}
+
+	v = &vic_devices[vic_id];
+	v->base = base;
+	v->valid_sources = valid_sources;
+	v->resume_sources = resume_sources;
+	v->irq = irq;
+	set_handle_irq(vic_handle_irq);
+	vic_id++;
+	v->domain = irq_domain_add_simple(node, fls(valid_sources), irq,
+					  &vic_irqdomain_ops, v);
+	/* create an IRQ mapping for each valid IRQ */
+	for (i = 0; i < fls(valid_sources); i++)
+		if (valid_sources & (1 << i))
+			irq_create_mapping(v->domain, i);
+}
+
+static void vic_ack_irq(struct irq_data *d)
+{
+	void __iomem *base = irq_data_get_irq_chip_data(d);
+	unsigned int irq = d->hwirq;
+	writel(1 << irq, base + VIC_INT_ENABLE_CLEAR);
+	/* moreover, clear the soft-triggered, in case it was the reason */
+	writel(1 << irq, base + VIC_INT_SOFT_CLEAR);
+}
+
+static void vic_mask_irq(struct irq_data *d)
+{
+	void __iomem *base = irq_data_get_irq_chip_data(d);
+	unsigned int irq = d->hwirq;
+	writel(1 << irq, base + VIC_INT_ENABLE_CLEAR);
+}
+
+static void vic_unmask_irq(struct irq_data *d)
+{
+	void __iomem *base = irq_data_get_irq_chip_data(d);
+	unsigned int irq = d->hwirq;
+	writel(1 << irq, base + VIC_INT_ENABLE);
+}
+
+#if defined(CONFIG_PM)
+static struct vic_device *vic_from_irq(unsigned int irq)
+{
+        struct vic_device *v = vic_devices;
+	unsigned int base_irq = irq & ~31;
+	int id;
+
+	for (id = 0; id < vic_id; id++, v++) {
+		if (v->irq == base_irq)
+			return v;
+	}
+
+	return NULL;
+}
+
+static int vic_set_wake(struct irq_data *d, unsigned int on)
+{
+	struct vic_device *v = vic_from_irq(d->irq);
+	unsigned int off = d->hwirq;
+	u32 bit = 1 << off;
+
+	if (!v)
+		return -EINVAL;
+
+	if (!(bit & v->resume_sources))
+		return -EINVAL;
+
+	if (on)
+		v->resume_irqs |= bit;
+	else
+		v->resume_irqs &= ~bit;
+
+	return 0;
+}
+#else
+#define vic_set_wake NULL
+#endif /* CONFIG_PM */
+
+static struct irq_chip vic_chip = {
+	.name		= "VIC",
+	.irq_ack	= vic_ack_irq,
+	.irq_mask	= vic_mask_irq,
+	.irq_unmask	= vic_unmask_irq,
+	.irq_set_wake	= vic_set_wake,
+};
+
+static void __init vic_disable(void __iomem *base)
+{
+	writel(0, base + VIC_INT_SELECT);
+	writel(0, base + VIC_INT_ENABLE);
+	writel(~0, base + VIC_INT_ENABLE_CLEAR);
+	writel(0, base + VIC_ITCR);
+	writel(~0, base + VIC_INT_SOFT_CLEAR);
+}
+
+static void __init vic_clear_interrupts(void __iomem *base)
+{
+	unsigned int i;
+
+	writel(0, base + VIC_PL190_VECT_ADDR);
+	for (i = 0; i < 19; i++) {
+		unsigned int value;
+
+		value = readl(base + VIC_PL190_VECT_ADDR);
+		writel(value, base + VIC_PL190_VECT_ADDR);
+	}
+}
+
+/*
+ * The PL190 cell from ARM has been modified by ST to handle 64 interrupts.
+ * The original cell has 32 interrupts, while the modified one has 64,
+ * replocating two blocks 0x00..0x1f in 0x20..0x3f. In that case
+ * the probe function is called twice, with base set to offset 000
+ *  and 020 within the page. We call this "second block".
+ */
+static void __init vic_init_st(void __iomem *base, unsigned int irq_start,
+			       u32 vic_sources, struct device_node *node)
+{
+	unsigned int i;
+	int vic_2nd_block = ((unsigned long)base & ~PAGE_MASK) != 0;
+
+	/* Disable all interrupts initially. */
+	vic_disable(base);
+
+	/*
+	 * Make sure we clear all existing interrupts. The vector registers
+	 * in this cell are after the second block of general registers,
+	 * so we can address them using standard offsets, but only from
+	 * the second base address, which is 0x20 in the page
+	 */
+	if (vic_2nd_block) {
+		vic_clear_interrupts(base);
+
+		/* ST has 16 vectors as well, but we don't enable them by now */
+		for (i = 0; i < 16; i++) {
+			void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4);
+			writel(0, reg);
+		}
+
+		writel(32, base + VIC_PL190_DEF_VECT_ADDR);
+	}
+
+	vic_register(base, irq_start, vic_sources, 0, node);
+}
+
+void __init __vic_init(void __iomem *base, int irq_start,
+			      u32 vic_sources, u32 resume_sources,
+			      struct device_node *node)
+{
+	unsigned int i;
+	u32 cellid = 0;
+	enum amba_vendor vendor;
+
+	/* Identify which VIC cell this one is, by reading the ID */
+	for (i = 0; i < 4; i++) {
+		void __iomem *addr;
+		addr = (void __iomem *)((u32)base & PAGE_MASK) + 0xfe0 + (i * 4);
+		cellid |= (readl(addr) & 0xff) << (8 * i);
+	}
+	vendor = (cellid >> 12) & 0xff;
+	printk(KERN_INFO "VIC @%p: id 0x%08x, vendor 0x%02x\n",
+	       base, cellid, vendor);
+
+	switch(vendor) {
+	case AMBA_VENDOR_ST:
+		vic_init_st(base, irq_start, vic_sources, node);
+		return;
+	default:
+		printk(KERN_WARNING "VIC: unknown vendor, continuing anyways\n");
+		/* fall through */
+	case AMBA_VENDOR_ARM:
+		break;
+	}
+
+	/* Disable all interrupts initially. */
+	vic_disable(base);
+
+	/* Make sure we clear all existing interrupts */
+	vic_clear_interrupts(base);
+
+	vic_init2(base);
+
+	vic_register(base, irq_start, vic_sources, resume_sources, node);
+}
+
+/**
+ * vic_init() - initialise a vectored interrupt controller
+ * @base: iomem base address
+ * @irq_start: starting interrupt number, must be muliple of 32
+ * @vic_sources: bitmask of interrupt sources to allow
+ * @resume_sources: bitmask of interrupt sources to allow for resume
+ */
+void __init vic_init(void __iomem *base, unsigned int irq_start,
+		     u32 vic_sources, u32 resume_sources)
+{
+	__vic_init(base, irq_start, vic_sources, resume_sources, NULL);
+}
+
+#ifdef CONFIG_OF
+int __init vic_of_init(struct device_node *node, struct device_node *parent)
+{
+	void __iomem *regs;
+
+	if (WARN(parent, "non-root VICs are not supported"))
+		return -EINVAL;
+
+	regs = of_iomap(node, 0);
+	if (WARN_ON(!regs))
+		return -EIO;
+
+	/*
+	 * Passing 0 as first IRQ makes the simple domain allocate descriptors
+	 */
+	__vic_init(regs, 0, ~0, ~0, node);
+
+	return 0;
+}
+IRQCHIP_DECLARE(arm_pl190_vic, "arm,pl190-vic", vic_of_init);
+IRQCHIP_DECLARE(arm_pl192_vic, "arm,pl192-vic", vic_of_init);
+IRQCHIP_DECLARE(arm_versatile_vic, "arm,versatile-vic", vic_of_init);
+#endif /* CONFIG OF */