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authorRob Herring <rob.herring@calxeda.com>2012-10-27 17:25:26 -0500
committerRob Herring <rob.herring@calxeda.com>2013-01-12 10:52:14 -0600
commit44430ec068b207f985aa00b1d34bb5085dbc39d5 (patch)
tree6d2e69370398a9702128eb786c6bcf2c5eddf3a7 /drivers/irqchip/irq-vic.c
parent48cf83dc12f2a5ef3ac4d74dc7b5e6403cb3cedb (diff)
downloadop-kernel-dev-44430ec068b207f985aa00b1d34bb5085dbc39d5.zip
op-kernel-dev-44430ec068b207f985aa00b1d34bb5085dbc39d5.tar.gz
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>
Diffstat (limited to 'drivers/irqchip/irq-vic.c')
-rw-r--r--drivers/irqchip/irq-vic.c489
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 */
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