/*
* Interrupt controller support for IBM Spruce
*
* Authors: Mark Greer, Matt Porter, and Johnnie Peters
* mgreer@mvista.com
* mporter@mvista.com
* jpeters@mvista.com
*
* 2001-2002 (c) MontaVista, Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
#include <linux/stddef.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/irq.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/irq.h>
#include "cpc700.h"
static void
cpc700_unmask_irq(unsigned int irq)
{
unsigned int tr_bits;
/*
* IRQ 31 is largest IRQ supported.
* IRQs 17-19 are reserved.
*/
if ((irq <= 31) && ((irq < 17) || (irq > 19))) {
tr_bits = CPC700_IN_32(CPC700_UIC_UICTR);
if ((tr_bits & (1 << (31 - irq))) == 0) {
/* level trigger interrupt, clear bit in status
* register */
CPC700_OUT_32(CPC700_UIC_UICSR, 1 << (31 - irq));
}
/* Know IRQ fits in entry 0 of ppc_cached_irq_mask[] */
ppc_cached_irq_mask[0] |= CPC700_UIC_IRQ_BIT(irq);
CPC700_OUT_32(CPC700_UIC_UICER, ppc_cached_irq_mask[0]);
}
return;
}
static void
cpc700_mask_irq(unsigned int irq)
{
/*
* IRQ 31 is largest IRQ supported.
* IRQs 17-19 are reserved.
*/
if ((irq <= 31) && ((irq < 17) || (irq > 19))) {
/* Know IRQ fits in entry 0 of ppc_cached_irq_mask[] */
ppc_cached_irq_mask[0] &=
~CPC700_UIC_IRQ_BIT(irq);
CPC700_OUT_32(CPC700_UIC_UICER, ppc_cached_irq_mask[0]);
}
return;
}
static void
cpc700_mask_and_ack_irq(unsigned int irq)
{
u_int bit;
/*
* IRQ 31 is largest IRQ supported.
* IRQs 17-19 are reserved.
*/
if ((irq <= 31) && ((irq < 17) || (irq > 19))) {
/* Know IRQ fits in entry 0 of ppc_cached_irq_mask[] */
bit = CPC700_UIC_IRQ_BIT(irq);
ppc_cached_irq_mask[0] &= ~bit;
CPC700_OUT_32(CPC700_UIC_UICER, ppc_cached_irq_mask[0]);
CPC700_OUT_32(CPC700_UIC_UICSR, bit); /* Write 1 clears IRQ */
}
return;
}
static struct hw_interrupt_type cpc700_pic = {
.typename = "CPC700 PIC",
.enable = cpc700_unmask_irq,
.disable = cpc700_mask_irq,
.ack = cpc700_mask_and_ack_irq,
};
__init static void
cpc700_pic_init_irq(unsigned int irq)
{
unsigned int tmp;
/* Set interrupt sense */
tmp = CPC700_IN_32(CPC700_UIC_UICTR);
if (cpc700_irq_assigns[irq][0] == 0) {
tmp &= ~CPC700_UIC_IRQ_BIT(irq);
} else {
tmp |= CPC700_UIC_IRQ_BIT(irq);
}
CPC700_OUT_32(CPC700_UIC_UICTR, tmp);
/* Set interrupt polarity */
tmp = CPC700_IN_32(CPC700_UIC_UICPR);
if (cpc700_irq_assigns[irq][1]) {
tmp |= CPC700_UIC_IRQ_BIT(irq);
} else {
tmp &= ~CPC700_UIC_IRQ_BIT(irq);
}
CPC700_OUT_32(CPC700_UIC_UICPR, tmp);
/* Set interrupt critical */
tmp = CPC700_IN_32(CPC700_UIC_UICCR);
tmp |= CPC700_UIC_IRQ_BIT(irq);
CPC700_OUT_32(CPC700_UIC_UICCR, tmp);
return;
}
__init void
cpc700_init_IRQ(void)
{
int i;
ppc_cached_irq_mask[0] = 0;
CPC700_OUT_32(CPC700_UIC_UICER, 0x00000000); /* Disable all irq's */
CPC700_OUT_32(CPC700_UIC_UICSR, 0xffffffff); /* Clear cur intrs */
CPC700_OUT_32(CPC700_UIC_UICCR, 0xffffffff); /* Gen INT not MCP */
CPC700_OUT_32(CPC700_UIC_UICPR, 0x00000000); /* Active low */
CPC700_OUT_32(CPC700_UIC_UICTR, 0x00000000); /* Level Sensitive */
CPC700_OUT_32(CPC700_UIC_UICVR, CPC700_UIC_UICVCR_0_HI);
/* IRQ 0 is highest */
for (i = 0; i < 17; i++) {
irq_desc[i].chip = &cpc700_pic;
cpc700_pic_init_irq(i);
}
for (i = 20; i < 32; i++) {
irq_desc[i].chip = &cpc700_pic;
cpc700_pic_init_irq(i);
}
return;
}
/*
* Find the highest IRQ that generating an interrupt, if any.
*/
int
cpc700_get_irq(struct pt_regs *regs)
{
int irq = 0;
u_int irq_status, irq_test = 1;
irq_status = CPC700_IN_32(CPC700_UIC_UICMSR);
do
{
if (irq_status & irq_test)
break;
irq++;
irq_test <<= 1;
} while (irq < NR_IRQS);
if (irq == NR_IRQS)
irq = 33;
return (31 - irq);
}
