xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision 411ba7fc)
1 /*
2  * This program is free software; you can redistribute  it and/or modify it
3  * under  the terms of  the GNU General  Public License as published by the
4  * Free Software Foundation;  either version 2 of the  License, or (at your
5  * option) any later version.
6  *
7  * Copyright (c) 2004 MIPS Inc
8  * Author: chris@mips.com
9  *
10  * Copyright (C) 2004, 06 Ralf Baechle <ralf@linux-mips.org>
11  */
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/kernel_stat.h>
17 #include <asm/io.h>
18 #include <asm/irq.h>
19 #include <asm/msc01_ic.h>
20 #include <asm/traps.h>
21 
22 static unsigned long _icctrl_msc;
23 #define MSC01_IC_REG_BASE	_icctrl_msc
24 
25 #define MSCIC_WRITE(reg, data)	do { *(volatile u32 *)(reg) = data; } while (0)
26 #define MSCIC_READ(reg, data)	do { data = *(volatile u32 *)(reg); } while (0)
27 
28 static unsigned int irq_base;
29 
30 /* mask off an interrupt */
31 static inline void mask_msc_irq(unsigned int irq)
32 {
33 	if (irq < (irq_base + 32))
34 		MSCIC_WRITE(MSC01_IC_DISL, 1<<(irq - irq_base));
35 	else
36 		MSCIC_WRITE(MSC01_IC_DISH, 1<<(irq - irq_base - 32));
37 }
38 
39 /* unmask an interrupt */
40 static inline void unmask_msc_irq(unsigned int irq)
41 {
42 	if (irq < (irq_base + 32))
43 		MSCIC_WRITE(MSC01_IC_ENAL, 1<<(irq - irq_base));
44 	else
45 		MSCIC_WRITE(MSC01_IC_ENAH, 1<<(irq - irq_base - 32));
46 }
47 
48 /*
49  * Masks and ACKs an IRQ
50  */
51 static void level_mask_and_ack_msc_irq(unsigned int irq)
52 {
53 	mask_msc_irq(irq);
54 	if (!cpu_has_veic)
55 		MSCIC_WRITE(MSC01_IC_EOI, 0);
56 	/* This actually needs to be a call into platform code */
57 	smtc_im_ack_irq(irq);
58 }
59 
60 /*
61  * Masks and ACKs an IRQ
62  */
63 static void edge_mask_and_ack_msc_irq(unsigned int irq)
64 {
65 	mask_msc_irq(irq);
66 	if (!cpu_has_veic)
67 		MSCIC_WRITE(MSC01_IC_EOI, 0);
68 	else {
69 		u32 r;
70 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
71 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
72 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
73 	}
74 	smtc_im_ack_irq(irq);
75 }
76 
77 /*
78  * End IRQ processing
79  */
80 static void end_msc_irq(unsigned int irq)
81 {
82 	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
83 		unmask_msc_irq(irq);
84 }
85 
86 /*
87  * Interrupt handler for interrupts coming from SOC-it.
88  */
89 void ll_msc_irq(void)
90 {
91  	unsigned int irq;
92 
93 	/* read the interrupt vector register */
94 	MSCIC_READ(MSC01_IC_VEC, irq);
95 	if (irq < 64)
96 		do_IRQ(irq + irq_base);
97 	else {
98 		/* Ignore spurious interrupt */
99 	}
100 }
101 
102 static void msc_bind_eic_interrupt(int irq, int set)
103 {
104 	MSCIC_WRITE(MSC01_IC_RAMW,
105 		    (irq<<MSC01_IC_RAMW_ADDR_SHF) | (set<<MSC01_IC_RAMW_DATA_SHF));
106 }
107 
108 static struct irq_chip msc_levelirq_type = {
109 	.name = "SOC-it-Level",
110 	.ack = level_mask_and_ack_msc_irq,
111 	.mask = mask_msc_irq,
112 	.mask_ack = level_mask_and_ack_msc_irq,
113 	.unmask = unmask_msc_irq,
114 	.eoi = unmask_msc_irq,
115 	.end = end_msc_irq,
116 };
117 
118 static struct irq_chip msc_edgeirq_type = {
119 	.name = "SOC-it-Edge",
120 	.ack = edge_mask_and_ack_msc_irq,
121 	.mask = mask_msc_irq,
122 	.mask_ack = edge_mask_and_ack_msc_irq,
123 	.unmask = unmask_msc_irq,
124 	.eoi = unmask_msc_irq,
125 	.end = end_msc_irq,
126 };
127 
128 
129 void __init init_msc_irqs(unsigned long icubase, unsigned int irqbase, msc_irqmap_t *imp, int nirq)
130 {
131 	_icctrl_msc = (unsigned long) ioremap(icubase, 0x40000);
132 
133 	/* Reset interrupt controller - initialises all registers to 0 */
134 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
135 
136 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
137 
138 	for (; nirq >= 0; nirq--, imp++) {
139 		int n = imp->im_irq;
140 
141 		switch (imp->im_type) {
142 		case MSC01_IRQ_EDGE:
143 			set_irq_chip(irqbase+n, &msc_edgeirq_type);
144 			if (cpu_has_veic)
145 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
146 			else
147 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
148 			break;
149 		case MSC01_IRQ_LEVEL:
150 			set_irq_chip(irqbase+n, &msc_levelirq_type);
151 			if (cpu_has_veic)
152 				MSCIC_WRITE(MSC01_IC_SUP+n*8, 0);
153 			else
154 				MSCIC_WRITE(MSC01_IC_SUP+n*8, imp->im_lvl);
155 		}
156 	}
157 
158 	irq_base = irqbase;
159 
160 	MSCIC_WRITE(MSC01_IC_GENA, MSC01_IC_GENA_GENA_BIT);	/* Enable interrupt generation */
161 
162 }
163