/*
* Copyright (C) 2008
* Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/err.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <mach/ipu.h>
#include "ipu_intern.h"
/*
* Register read / write - shall be inlined by the compiler
*/
static u32 ipu_read_reg(struct ipu *ipu, unsigned long reg)
{
return __raw_readl(ipu->reg_ipu + reg);
}
static void ipu_write_reg(struct ipu *ipu, u32 value, unsigned long reg)
{
__raw_writel(value, ipu->reg_ipu + reg);
}
/*
* IPU IRQ chip driver
*/
#define IPU_IRQ_NR_FN_BANKS 3
#define IPU_IRQ_NR_ERR_BANKS 2
#define IPU_IRQ_NR_BANKS (IPU_IRQ_NR_FN_BANKS + IPU_IRQ_NR_ERR_BANKS)
struct ipu_irq_bank {
unsigned int control;
unsigned int status;
spinlock_t lock;
struct ipu *ipu;
};
static struct ipu_irq_bank irq_bank[IPU_IRQ_NR_BANKS] = {
/* 3 groups of functional interrupts */
{
.control = IPU_INT_CTRL_1,
.status = IPU_INT_STAT_1,
}, {
.control = IPU_INT_CTRL_2,
.status = IPU_INT_STAT_2,
}, {
.control = IPU_INT_CTRL_3,
.status = IPU_INT_STAT_3,
},
/* 2 groups of error interrupts */
{
.control = IPU_INT_CTRL_4,
.status = IPU_INT_STAT_4,
}, {
.control = IPU_INT_CTRL_5,
.status = IPU_INT_STAT_5,
},
};
struct ipu_irq_map {
unsigned int irq;
int source;
struct ipu_irq_bank *bank;
struct ipu *ipu;
};
static struct ipu_irq_map irq_map[CONFIG_MX3_IPU_IRQS];
/* Protects allocations from the above array of maps */
static DEFINE_MUTEX(map_lock);
/* Protects register accesses and individual mappings */
static DEFINE_SPINLOCK(bank_lock);
static struct ipu_irq_map *src2map(unsigned int src)
{
int i;
for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++)
if (irq_map[i].source == src)
return irq_map + i;
return NULL;
}
static void ipu_irq_unmask(unsigned int irq)
{
struct ipu_irq_map *map = get_irq_chip_data(irq);
struct ipu_irq_bank *bank;
uint32_t reg;
unsigned long lock_flags;
spin_lock_irqsave(&bank_lock, lock_flags);
bank = map->bank;
if (!bank) {
spin_unlock_irqrestore(&bank_lock, lock_flags);
pr_err("IPU: %s(%u) - unmapped!\n", __func__, irq);
return;
}
reg = ipu_read_reg(bank->ipu, bank->control);
reg |= (1UL << (map->source & 31));
ipu_write_reg(bank->ipu, reg, bank->control);
spin_unlock_irqrestore(&bank_lock, lock_flags);
}
static void ipu_irq_mask(unsigned int irq)
{
struct ipu_irq_map *map = get_irq_chip_data(irq);
struct ipu_irq_bank *bank;
uint32_t reg;
unsigned long lock_flags;
spin_lock_irqsave(&bank_lock, lock_flags);
bank = map->bank;
if (!bank) {
spin_unlock_irqrestore(&bank_lock, lock_flags);
pr_err("IPU: %s(%u) - unmapped!\n", __func__, irq);
return;
}
reg = ipu_read_reg(bank->ipu, bank->control);
reg &= ~(1UL << (map->source & 31));
ipu_write_reg(bank->ipu, reg, bank->control);
spin_unlock_irqrestore(&bank_lock, lock_flags);
}
static void ipu_irq_ack(unsigned int irq)
{
struct ipu_irq_map *map = get_irq_chip_data(irq);
struct ipu_irq_bank *bank;
unsigned long lock_flags;
spin_lock_irqsave(&bank_lock, lock_flags);
bank = map->bank;
if (!bank) {
spin_unlock_irqrestore(&bank_lock, lock_flags);
pr_err("IPU: %s(%u) - unmapped!\n", __func__, irq);
return;
}
ipu_write_reg(bank->ipu, 1UL << (map->source & 31), bank->status);
spin_unlock_irqrestore(&bank_lock, lock_flags);
}
/**
* ipu_irq_status() - returns the current interrupt status of the specified IRQ.
* @irq: interrupt line to get status for.
* @return: true if the interrupt is pending/asserted or false if the
* interrupt is not pending.
*/
bool ipu_irq_status(unsigned int irq)
{
struct ipu_irq_map *map = get_irq_chip_data(irq);
struct ipu_irq_bank *bank;
unsigned long lock_flags;
bool ret;
spin_lock_irqsave(&bank_lock, lock_flags);
bank = map->bank;
ret = bank && ipu_read_reg(bank->ipu, bank->status) &
(1UL << (map->source & 31));
spin_unlock_irqrestore(&bank_lock, lock_flags);
return ret;
}
/**
* ipu_irq_map() - map an IPU interrupt source to an IRQ number
* @source: interrupt source bit position (see below)
* @return: mapped IRQ number or negative error code
*
* The source parameter has to be explained further. On i.MX31 IPU has 137 IRQ
* sources, they are broken down in 5 32-bit registers, like 32, 32, 24, 32, 17.
* However, the source argument of this function is not the sequence number of
* the possible IRQ, but rather its bit position. So, first interrupt in fourth
* register has source number 96, and not 88. This makes calculations easier,
* and also provides forward compatibility with any future IPU implementations
* with any interrupt bit assignments.
*/
int ipu_irq_map(unsigned int source)
{
int i, ret = -ENOMEM;
struct ipu_irq_map *map;
might_sleep();
mutex_lock(&map_lock);
map = src2map(source);
if (map) {
pr_err("IPU: Source %u already mapped to IRQ %u\n", source, map->irq);
ret = -EBUSY;
goto out;
}
for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++) {
if (irq_map[i].source < 0) {
unsigned long lock_flags;
spin_lock_irqsave(&bank_lock, lock_flags);
irq_map[i].source = source;
irq_map[i].bank = irq_bank + source / 32;
spin_unlock_irqrestore(&bank_lock, lock_flags);
ret = irq_map[i].irq;
pr_debug("IPU: mapped source %u to IRQ %u\n",
source, ret);
break;
}
}
out:
mutex_unlock(&map_lock);
if (ret < 0)
pr_err("IPU: couldn't map source %u: %d\n", source, ret);
return ret;
}
/**
* ipu_irq_map() - map an IPU interrupt source to an IRQ number
* @source: interrupt source bit position (see ipu_irq_map())
* @return: 0 or negative error code
*/
int ipu_irq_unmap(unsigned int source)
{
int i, ret = -EINVAL;
might_sleep();
mutex_lock(&map_lock);
for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++) {
if (irq_map[i].source == source) {
unsigned long lock_flags;
pr_debug("IPU: unmapped source %u from IRQ %u\n",
source, irq_map[i].irq);
spin_lock_irqsave(&bank_lock, lock_flags);
irq_map[i].source = -EINVAL;
irq_map[i].bank = NULL;
spin_unlock_irqrestore(&bank_lock, lock_flags);
ret = 0;
break;
}
}
mutex_unlock(&map_lock);
return ret;
}
/* Chained IRQ handler for IPU error interrupt */
static void ipu_irq_err(unsigned int irq, struct irq_desc *desc)
{
struct ipu *ipu = get_irq_data(irq);
u32 status;
int i, line;
for (i = IPU_IRQ_NR_FN_BANKS; i < IPU_IRQ_NR_BANKS; i++) {
struct ipu_irq_bank *bank = irq_bank + i;
spin_lock(&bank_lock);
status = ipu_read_reg(ipu, bank->status);
/*
* Don't think we have to clear all interrupts here, they will
* be acked by ->handle_irq() (handle_level_irq). However, we
* might want to clear unhandled interrupts after the loop...
*/
status &= ipu_read_reg(ipu, bank->control);
spin_unlock(&bank_lock);
while ((line = ffs(status))) {
struct ipu_irq_map *map;
line--;
status &= ~(1UL << line);
spin_lock(&bank_lock);
map = src2map(32 * i + line);
if (map)
irq = map->irq;
spin_unlock(&bank_lock);
if (!map) {
pr_err("IPU: Interrupt on unmapped source %u bank %d\n",
line, i);
continue;
}
generic_handle_irq(irq);
}
}
}
/* Chained IRQ handler for IPU function interrupt */
static void ipu_irq_fn(unsigned int irq, struct irq_desc *desc)
{
struct ipu *ipu = get_irq_data(irq);
u32 status;
int i, line;
for (i = 0; i < IPU_IRQ_NR_FN_BANKS; i++) {
struct ipu_irq_bank *bank = irq_bank + i;
spin_lock(&bank_lock);
status = ipu_read_reg(ipu, bank->status);
/* Not clearing all interrupts, see above */
status &= ipu_read_reg(ipu, bank->control);
spin_unlock(&bank_lock);
while ((line = ffs(status))) {
struct ipu_irq_map *map;
line--;
status &= ~(1UL << line);
spin_lock(&bank_lock);
map = src2map(32 * i + line);
if (map)
irq = map->irq;
spin_unlock(&bank_lock);
if (!map) {
pr_err("IPU: Interrupt on unmapped source %u bank %d\n",
line, i);
continue;
}
generic_handle_irq(irq);
}
}
}
static struct irq_chip ipu_irq_chip = {
.name = "ipu_irq",
.ack = ipu_irq_ack,
.mask = ipu_irq_mask,
.unmask = ipu_irq_unmask,
};
/* Install the IRQ handler */
int ipu_irq_attach_irq(struct ipu *ipu, struct platform_device *dev)
{
struct ipu_platform_data *pdata = dev->dev.platform_data;
unsigned int irq, irq_base, i;
irq_base = pdata->irq_base;
for (i = 0; i < IPU_IRQ_NR_BANKS; i++)
irq_bank[i].ipu = ipu;
for (i = 0; i < CONFIG_MX3_IPU_IRQS; i++) {
int ret;
irq = irq_base + i;
ret = set_irq_chip(irq, &ipu_irq_chip);
if (ret < 0)
return ret;
ret = set_irq_chip_data(irq, irq_map + i);
if (ret < 0)
return ret;
irq_map[i].ipu = ipu;
irq_map[i].irq = irq;
irq_map[i].source = -EINVAL;
set_irq_handler(irq, handle_level_irq);
#ifdef CONFIG_ARM
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
#endif
}
set_irq_data(ipu->irq_fn, ipu);
set_irq_chained_handler(ipu->irq_fn, ipu_irq_fn);
set_irq_data(ipu->irq_err, ipu);
set_irq_chained_handler(ipu->irq_err, ipu_irq_err);
return 0;
}
void ipu_irq_detach_irq(struct ipu *ipu, struct platform_device *dev)
{
struct ipu_platform_data *pdata = dev->dev.platform_data;
unsigned int irq, irq_base;
irq_base = pdata->irq_base;
set_irq_chained_handler(ipu->irq_fn, NULL);
set_irq_data(ipu->irq_fn, NULL);
set_irq_chained_handler(ipu->irq_err, NULL);
set_irq_data(ipu->irq_err, NULL);
for (irq = irq_base; irq < irq_base + CONFIG_MX3_IPU_IRQS; irq++) {
#ifdef CONFIG_ARM
set_irq_flags(irq, 0);
#endif
set_irq_chip(irq, NULL);
set_irq_chip_data(irq, NULL);
}
}
