linux/drivers/irqchip/irq-vic.c
Tomasz Figa 81e9c1794f irqchip: vic: Parse interrupt and resume masks from device tree
This patch extends vic_of_init to parse valid interrupt sources
and resume sources masks from device tree.

If mask values are not specified in device tree, all sources
are assumed to be valid, as before this patch.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2013-09-17 06:48:27 +09:00

496 lines
13 KiB
C

/*
* 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/irq.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 <linux/irqchip/arm-vic.h>
#include <asm/exception.h>
#include <asm/irq.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 -EPERM;
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;
u32 interrupt_mask = ~0;
u32 wakeup_mask = ~0;
if (WARN(parent, "non-root VICs are not supported"))
return -EINVAL;
regs = of_iomap(node, 0);
if (WARN_ON(!regs))
return -EIO;
of_property_read_u32(node, "valid-mask", &interrupt_mask);
of_property_read_u32(node, "valid-wakeup-mask", &wakeup_mask);
/*
* Passing 0 as first IRQ makes the simple domain allocate descriptors
*/
__vic_init(regs, 0, interrupt_mask, wakeup_mask, 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 */