1/*
2 * This file define the irq handler for MSP SLM subsystem interrupts.
3 *
4 * Copyright 2005-2006 PMC-Sierra, Inc, derived from irq_cpu.c
5 * Author: Andrew Hughes, Andrew_Hughes@pmc-sierra.com
6 *
7 * This program is free software; you can redistribute	it and/or modify it
8 * under  the terms of	the GNU General	 Public License as published by the
9 * Free Software Foundation;  either version 2 of the  License, or (at your
10 * option) any later version.
11 */
12
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/kernel.h>
16#include <linux/bitops.h>
17
18#include <asm/mipsregs.h>
19
20#include <msp_slp_int.h>
21#include <msp_regs.h>
22
23static inline void unmask_msp_slp_irq(struct irq_data *d)
24{
25	unsigned int irq = d->irq;
26
27	/* check for PER interrupt range */
28	if (irq < MSP_PER_INTBASE)
29		*SLP_INT_MSK_REG |= (1 << (irq - MSP_SLP_INTBASE));
30	else
31		*PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
32}
33
34static inline void mask_msp_slp_irq(struct irq_data *d)
35{
36	unsigned int irq = d->irq;
37
38	/* check for PER interrupt range */
39	if (irq < MSP_PER_INTBASE)
40		*SLP_INT_MSK_REG &= ~(1 << (irq - MSP_SLP_INTBASE));
41	else
42		*PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
43}
44
45/*
46 * While we ack the interrupt interrupts are disabled and thus we don't need
47 * to deal with concurrency issues.  Same for msp_slp_irq_end.
48 */
49static inline void ack_msp_slp_irq(struct irq_data *d)
50{
51	unsigned int irq = d->irq;
52
53	/* check for PER interrupt range */
54	if (irq < MSP_PER_INTBASE)
55		*SLP_INT_STS_REG = (1 << (irq - MSP_SLP_INTBASE));
56	else
57		*PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
58}
59
60static struct irq_chip msp_slp_irq_controller = {
61	.name = "MSP_SLP",
62	.irq_ack = ack_msp_slp_irq,
63	.irq_mask = mask_msp_slp_irq,
64	.irq_unmask = unmask_msp_slp_irq,
65};
66
67void __init msp_slp_irq_init(void)
68{
69	int i;
70
71	/* Mask/clear interrupts. */
72	*SLP_INT_MSK_REG = 0x00000000;
73	*PER_INT_MSK_REG = 0x00000000;
74	*SLP_INT_STS_REG = 0xFFFFFFFF;
75	*PER_INT_STS_REG = 0xFFFFFFFF;
76
77	/* initialize all the IRQ descriptors */
78	for (i = MSP_SLP_INTBASE; i < MSP_PER_INTBASE + 32; i++)
79		irq_set_chip_and_handler(i, &msp_slp_irq_controller,
80					 handle_level_irq);
81}
82
83void msp_slp_irq_dispatch(void)
84{
85	u32 pending;
86	int intbase;
87
88	intbase = MSP_SLP_INTBASE;
89	pending = *SLP_INT_STS_REG & *SLP_INT_MSK_REG;
90
91	/* check for PER interrupt */
92	if (pending == (1 << (MSP_INT_PER - MSP_SLP_INTBASE))) {
93		intbase = MSP_PER_INTBASE;
94		pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
95	}
96
97	/* check for spurious interrupt */
98	if (pending == 0x00000000) {
99		printk(KERN_ERR "Spurious %s interrupt?\n",
100			(intbase == MSP_SLP_INTBASE) ? "SLP" : "PER");
101		return;
102	}
103
104	/* dispatch the irq */
105	do_IRQ(ffs(pending) + intbase - 1);
106}
107