1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * This file define the irq handler for MSP SLM subsystem interrupts.
  4 *
  5 * Copyright 2005-2006 PMC-Sierra, Inc, derived from irq_cpu.c
  6 * Author: Andrew Hughes, Andrew_Hughes@pmc-sierra.com
  7 */
  8
  9#include <linux/init.h>
 10#include <linux/interrupt.h>
 11#include <linux/kernel.h>
 12#include <linux/bitops.h>
 13
 14#include <asm/mipsregs.h>
 15
 16#include <msp_slp_int.h>
 17#include <msp_regs.h>
 18
 19static inline void unmask_msp_slp_irq(struct irq_data *d)
 20{
 21	unsigned int irq = d->irq;
 22
 23	/* check for PER interrupt range */
 24	if (irq < MSP_PER_INTBASE)
 25		*SLP_INT_MSK_REG |= (1 << (irq - MSP_SLP_INTBASE));
 26	else
 27		*PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
 28}
 29
 30static inline void mask_msp_slp_irq(struct irq_data *d)
 31{
 32	unsigned int irq = d->irq;
 33
 34	/* check for PER interrupt range */
 35	if (irq < MSP_PER_INTBASE)
 36		*SLP_INT_MSK_REG &= ~(1 << (irq - MSP_SLP_INTBASE));
 37	else
 38		*PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
 39}
 40
 41/*
 42 * While we ack the interrupt interrupts are disabled and thus we don't need
 43 * to deal with concurrency issues.  Same for msp_slp_irq_end.
 44 */
 45static inline void ack_msp_slp_irq(struct irq_data *d)
 46{
 47	unsigned int irq = d->irq;
 48
 49	/* check for PER interrupt range */
 50	if (irq < MSP_PER_INTBASE)
 51		*SLP_INT_STS_REG = (1 << (irq - MSP_SLP_INTBASE));
 52	else
 53		*PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
 54}
 55
 56static struct irq_chip msp_slp_irq_controller = {
 57	.name = "MSP_SLP",
 58	.irq_ack = ack_msp_slp_irq,
 59	.irq_mask = mask_msp_slp_irq,
 60	.irq_unmask = unmask_msp_slp_irq,
 61};
 62
 63void __init msp_slp_irq_init(void)
 64{
 65	int i;
 66
 67	/* Mask/clear interrupts. */
 68	*SLP_INT_MSK_REG = 0x00000000;
 69	*PER_INT_MSK_REG = 0x00000000;
 70	*SLP_INT_STS_REG = 0xFFFFFFFF;
 71	*PER_INT_STS_REG = 0xFFFFFFFF;
 72
 73	/* initialize all the IRQ descriptors */
 74	for (i = MSP_SLP_INTBASE; i < MSP_PER_INTBASE + 32; i++)
 75		irq_set_chip_and_handler(i, &msp_slp_irq_controller,
 76					 handle_level_irq);
 77}
 78
 79void msp_slp_irq_dispatch(void)
 80{
 81	u32 pending;
 82	int intbase;
 83
 84	intbase = MSP_SLP_INTBASE;
 85	pending = *SLP_INT_STS_REG & *SLP_INT_MSK_REG;
 86
 87	/* check for PER interrupt */
 88	if (pending == (1 << (MSP_INT_PER - MSP_SLP_INTBASE))) {
 89		intbase = MSP_PER_INTBASE;
 90		pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
 91	}
 92
 93	/* check for spurious interrupt */
 94	if (pending == 0x00000000) {
 95		printk(KERN_ERR "Spurious %s interrupt?\n",
 96			(intbase == MSP_SLP_INTBASE) ? "SLP" : "PER");
 97		return;
 98	}
 99
100	/* dispatch the irq */
101	do_IRQ(ffs(pending) + intbase - 1);
102}