https://github.com/torvalds/linux
Tip revision: f0e615c3cb72b42191b558c130409335812621d8 authored by Linus Torvalds on 19 April 2011, 04:26:00 UTC
Linux 2.6.39-rc4
Linux 2.6.39-rc4
Tip revision: f0e615c
vic.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/init.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/sysdev.h>
#include <linux/device.h>
#include <linux/amba/bus.h>
#include <asm/mach/irq.h>
#include <asm/hardware/vic.h>
#if defined(CONFIG_PM)
/**
* struct vic_device - VIC PM device
* @sysdev: The system device which is registered.
* @irq: The IRQ number for the base of the VIC.
* @base: The register base for the VIC.
* @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.
*/
struct vic_device {
struct sys_device sysdev;
void __iomem *base;
int irq;
u32 resume_sources;
u32 resume_irqs;
u32 int_select;
u32 int_enable;
u32 soft_int;
u32 protect;
};
/* we cannot allocate memory when VICs are initially registered */
static struct vic_device vic_devices[CONFIG_ARM_VIC_NR];
static int vic_id;
static inline struct vic_device *to_vic(struct sys_device *sys)
{
return container_of(sys, struct vic_device, sysdev);
}
#endif /* CONFIG_PM */
/**
* 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);
}
#if defined(CONFIG_PM)
static int vic_class_resume(struct sys_device *dev)
{
struct vic_device *vic = to_vic(dev);
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);
return 0;
}
static int vic_class_suspend(struct sys_device *dev, pm_message_t state)
{
struct vic_device *vic = to_vic(dev);
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);
return 0;
}
struct sysdev_class vic_class = {
.name = "vic",
.suspend = vic_class_suspend,
.resume = vic_class_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)
{
struct vic_device *dev = vic_devices;
int err;
int id;
if (vic_id == 0)
return 0;
err = sysdev_class_register(&vic_class);
if (err) {
printk(KERN_ERR "%s: cannot register class\n", __func__);
return err;
}
for (id = 0; id < vic_id; id++, dev++) {
dev->sysdev.id = id;
dev->sysdev.cls = &vic_class;
err = sysdev_register(&dev->sysdev);
if (err) {
printk(KERN_ERR "%s: failed to register device\n",
__func__);
return err;
}
}
return 0;
}
late_initcall(vic_pm_init);
/**
* vic_pm_register - Register a VIC for later power management control
* @base: The base address of the VIC.
* @irq: The base IRQ for the VIC.
* @resume_sources: bitmask of interrupts allowed for resume sources.
*
* 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.
*/
static void __init vic_pm_register(void __iomem *base, unsigned int irq, u32 resume_sources)
{
struct vic_device *v;
if (vic_id >= ARRAY_SIZE(vic_devices))
printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__);
else {
v = &vic_devices[vic_id];
v->base = base;
v->resume_sources = resume_sources;
v->irq = irq;
vic_id++;
}
}
#else
static inline void vic_pm_register(void __iomem *base, unsigned int irq, u32 arg1) { }
#endif /* CONFIG_PM */
static void vic_ack_irq(struct irq_data *d)
{
void __iomem *base = irq_data_get_irq_chip_data(d);
unsigned int irq = d->irq & 31;
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->irq & 31;
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->irq & 31;
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->irq & 31;
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_IRQ_STATUS);
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);
}
}
static void __init vic_set_irq_sources(void __iomem *base,
unsigned int irq_start, u32 vic_sources)
{
unsigned int i;
for (i = 0; i < 32; i++) {
if (vic_sources & (1 << i)) {
unsigned int irq = irq_start + i;
irq_set_chip_and_handler(irq, &vic_chip,
handle_level_irq);
irq_set_chip_data(irq, base);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
}
}
}
/*
* 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)
{
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_set_irq_sources(base, irq_start, vic_sources);
}
/**
* 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)
{
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++) {
u32 addr = ((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);
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_set_irq_sources(base, irq_start, vic_sources);
vic_pm_register(base, irq_start, resume_sources);
}