/*
* intc.c -- interrupt controller or ColdFire 5272 SoC
*
* (C) Copyright 2009, Greg Ungerer <gerg@snapgear.com>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/traps.h>
/*
* The 5272 ColdFire interrupt controller is nothing like any other
* ColdFire interrupt controller - it truly is completely different.
* Given its age it is unlikely to be used on any other ColdFire CPU.
*/
/*
* The masking and priproty setting of interrupts on the 5272 is done
* via a set of 4 "Interrupt Controller Registers" (ICR). There is a
* loose mapping of vector number to register and internal bits, but
* a table is the easiest and quickest way to map them.
*
* Note that the external interrupts are edge triggered (unlike the
* internal interrupt sources which are level triggered). Which means
* they also need acknowledging via acknowledge bits.
*/
struct irqmap {
unsigned int icr;
unsigned char index;
unsigned char ack;
};
static struct irqmap intc_irqmap[MCFINT_VECMAX - MCFINT_VECBASE] = {
/*MCF_IRQ_SPURIOUS*/ { .icr = 0, .index = 0, .ack = 0, },
/*MCF_IRQ_EINT1*/ { .icr = MCFSIM_ICR1, .index = 28, .ack = 1, },
/*MCF_IRQ_EINT2*/ { .icr = MCFSIM_ICR1, .index = 24, .ack = 1, },
/*MCF_IRQ_EINT3*/ { .icr = MCFSIM_ICR1, .index = 20, .ack = 1, },
/*MCF_IRQ_EINT4*/ { .icr = MCFSIM_ICR1, .index = 16, .ack = 1, },
/*MCF_IRQ_TIMER1*/ { .icr = MCFSIM_ICR1, .index = 12, .ack = 0, },
/*MCF_IRQ_TIMER2*/ { .icr = MCFSIM_ICR1, .index = 8, .ack = 0, },
/*MCF_IRQ_TIMER3*/ { .icr = MCFSIM_ICR1, .index = 4, .ack = 0, },
/*MCF_IRQ_TIMER4*/ { .icr = MCFSIM_ICR1, .index = 0, .ack = 0, },
/*MCF_IRQ_UART1*/ { .icr = MCFSIM_ICR2, .index = 28, .ack = 0, },
/*MCF_IRQ_UART2*/ { .icr = MCFSIM_ICR2, .index = 24, .ack = 0, },
/*MCF_IRQ_PLIP*/ { .icr = MCFSIM_ICR2, .index = 20, .ack = 0, },
/*MCF_IRQ_PLIA*/ { .icr = MCFSIM_ICR2, .index = 16, .ack = 0, },
/*MCF_IRQ_USB0*/ { .icr = MCFSIM_ICR2, .index = 12, .ack = 0, },
/*MCF_IRQ_USB1*/ { .icr = MCFSIM_ICR2, .index = 8, .ack = 0, },
/*MCF_IRQ_USB2*/ { .icr = MCFSIM_ICR2, .index = 4, .ack = 0, },
/*MCF_IRQ_USB3*/ { .icr = MCFSIM_ICR2, .index = 0, .ack = 0, },
/*MCF_IRQ_USB4*/ { .icr = MCFSIM_ICR3, .index = 28, .ack = 0, },
/*MCF_IRQ_USB5*/ { .icr = MCFSIM_ICR3, .index = 24, .ack = 0, },
/*MCF_IRQ_USB6*/ { .icr = MCFSIM_ICR3, .index = 20, .ack = 0, },
/*MCF_IRQ_USB7*/ { .icr = MCFSIM_ICR3, .index = 16, .ack = 0, },
/*MCF_IRQ_DMA*/ { .icr = MCFSIM_ICR3, .index = 12, .ack = 0, },
/*MCF_IRQ_ERX*/ { .icr = MCFSIM_ICR3, .index = 8, .ack = 0, },
/*MCF_IRQ_ETX*/ { .icr = MCFSIM_ICR3, .index = 4, .ack = 0, },
/*MCF_IRQ_ENTC*/ { .icr = MCFSIM_ICR3, .index = 0, .ack = 0, },
/*MCF_IRQ_QSPI*/ { .icr = MCFSIM_ICR4, .index = 28, .ack = 0, },
/*MCF_IRQ_EINT5*/ { .icr = MCFSIM_ICR4, .index = 24, .ack = 1, },
/*MCF_IRQ_EINT6*/ { .icr = MCFSIM_ICR4, .index = 20, .ack = 1, },
/*MCF_IRQ_SWTO*/ { .icr = MCFSIM_ICR4, .index = 16, .ack = 0, },
};
/*
* The act of masking the interrupt also has a side effect of 'ack'ing
* an interrupt on this irq (for the external irqs). So this mask function
* is also an ack_mask function.
*/
static void intc_irq_mask(struct irq_data *d)
{
unsigned int irq = d->irq;
if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
u32 v;
irq -= MCFINT_VECBASE;
v = 0x8 << intc_irqmap[irq].index;
writel(v, intc_irqmap[irq].icr);
}
}
static void intc_irq_unmask(struct irq_data *d)
{
unsigned int irq = d->irq;
if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
u32 v;
irq -= MCFINT_VECBASE;
v = 0xd << intc_irqmap[irq].index;
writel(v, intc_irqmap[irq].icr);
}
}
static void intc_irq_ack(struct irq_data *d)
{
unsigned int irq = d->irq;
/* Only external interrupts are acked */
if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
irq -= MCFINT_VECBASE;
if (intc_irqmap[irq].ack) {
u32 v;
v = readl(intc_irqmap[irq].icr);
v &= (0x7 << intc_irqmap[irq].index);
v |= (0x8 << intc_irqmap[irq].index);
writel(v, intc_irqmap[irq].icr);
}
}
}
static int intc_irq_set_type(struct irq_data *d, unsigned int type)
{
unsigned int irq = d->irq;
if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
irq -= MCFINT_VECBASE;
if (intc_irqmap[irq].ack) {
u32 v;
v = readl(MCFSIM_PITR);
if (type == IRQ_TYPE_EDGE_FALLING)
v &= ~(0x1 << (32 - irq));
else
v |= (0x1 << (32 - irq));
writel(v, MCFSIM_PITR);
}
}
return 0;
}
/*
* Simple flow handler to deal with the external edge triggered interrupts.
* We need to be careful with the masking/acking due to the side effects
* of masking an interrupt.
*/
static void intc_external_irq(unsigned int irq, struct irq_desc *desc)
{
irq_desc_get_chip(desc)->irq_ack(&desc->irq_data);
handle_simple_irq(irq, desc);
}
static struct irq_chip intc_irq_chip = {
.name = "CF-INTC",
.irq_mask = intc_irq_mask,
.irq_unmask = intc_irq_unmask,
.irq_mask_ack = intc_irq_mask,
.irq_ack = intc_irq_ack,
.irq_set_type = intc_irq_set_type,
};
void __init init_IRQ(void)
{
int irq, edge;
/* Mask all interrupt sources */
writel(0x88888888, MCFSIM_ICR1);
writel(0x88888888, MCFSIM_ICR2);
writel(0x88888888, MCFSIM_ICR3);
writel(0x88888888, MCFSIM_ICR4);
for (irq = 0; (irq < NR_IRQS); irq++) {
irq_set_chip(irq, &intc_irq_chip);
edge = 0;
if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX))
edge = intc_irqmap[irq - MCFINT_VECBASE].ack;
if (edge) {
irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
irq_set_handler(irq, intc_external_irq);
} else {
irq_set_irq_type(irq, IRQ_TYPE_LEVEL_HIGH);
irq_set_handler(irq, handle_level_irq);
}
}
}
