xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision 1c2dd16a)
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/interrupt.h>
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/kernel_stat.h>
16 #include <asm/io.h>
17 #include <asm/irq.h>
18 #include <asm/msc01_ic.h>
19 #include <asm/traps.h>
20 
21 static unsigned long _icctrl_msc;
22 #define MSC01_IC_REG_BASE	_icctrl_msc
23 
24 #define MSCIC_WRITE(reg, data)	do { *(volatile u32 *)(reg) = data; } while (0)
25 #define MSCIC_READ(reg, data)	do { data = *(volatile u32 *)(reg); } while (0)
26 
27 static unsigned int irq_base;
28 
29 /* mask off an interrupt */
30 static inline void mask_msc_irq(struct irq_data *d)
31 {
32 	unsigned int irq = d->irq;
33 
34 	if (irq < (irq_base + 32))
35 		MSCIC_WRITE(MSC01_IC_DISL, 1<<(irq - irq_base));
36 	else
37 		MSCIC_WRITE(MSC01_IC_DISH, 1<<(irq - irq_base - 32));
38 }
39 
40 /* unmask an interrupt */
41 static inline void unmask_msc_irq(struct irq_data *d)
42 {
43 	unsigned int irq = d->irq;
44 
45 	if (irq < (irq_base + 32))
46 		MSCIC_WRITE(MSC01_IC_ENAL, 1<<(irq - irq_base));
47 	else
48 		MSCIC_WRITE(MSC01_IC_ENAH, 1<<(irq - irq_base - 32));
49 }
50 
51 /*
52  * Masks and ACKs an IRQ
53  */
54 static void level_mask_and_ack_msc_irq(struct irq_data *d)
55 {
56 	mask_msc_irq(d);
57 	if (!cpu_has_veic)
58 		MSCIC_WRITE(MSC01_IC_EOI, 0);
59 }
60 
61 /*
62  * Masks and ACKs an IRQ
63  */
64 static void edge_mask_and_ack_msc_irq(struct irq_data *d)
65 {
66 	unsigned int irq = d->irq;
67 
68 	mask_msc_irq(d);
69 	if (!cpu_has_veic)
70 		MSCIC_WRITE(MSC01_IC_EOI, 0);
71 	else {
72 		u32 r;
73 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
74 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
75 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
76 	}
77 }
78 
79 /*
80  * Interrupt handler for interrupts coming from SOC-it.
81  */
82 void ll_msc_irq(void)
83 {
84 	unsigned int irq;
85 
86 	/* read the interrupt vector register */
87 	MSCIC_READ(MSC01_IC_VEC, irq);
88 	if (irq < 64)
89 		do_IRQ(irq + irq_base);
90 	else {
91 		/* Ignore spurious interrupt */
92 	}
93 }
94 
95 static void msc_bind_eic_interrupt(int irq, int set)
96 {
97 	MSCIC_WRITE(MSC01_IC_RAMW,
98 		    (irq<<MSC01_IC_RAMW_ADDR_SHF) | (set<<MSC01_IC_RAMW_DATA_SHF));
99 }
100 
101 static struct irq_chip msc_levelirq_type = {
102 	.name = "SOC-it-Level",
103 	.irq_ack = level_mask_and_ack_msc_irq,
104 	.irq_mask = mask_msc_irq,
105 	.irq_mask_ack = level_mask_and_ack_msc_irq,
106 	.irq_unmask = unmask_msc_irq,
107 	.irq_eoi = unmask_msc_irq,
108 };
109 
110 static struct irq_chip msc_edgeirq_type = {
111 	.name = "SOC-it-Edge",
112 	.irq_ack = edge_mask_and_ack_msc_irq,
113 	.irq_mask = mask_msc_irq,
114 	.irq_mask_ack = edge_mask_and_ack_msc_irq,
115 	.irq_unmask = unmask_msc_irq,
116 	.irq_eoi = unmask_msc_irq,
117 };
118 
119 
120 void __init init_msc_irqs(unsigned long icubase, unsigned int irqbase, msc_irqmap_t *imp, int nirq)
121 {
122 	_icctrl_msc = (unsigned long) ioremap(icubase, 0x40000);
123 
124 	/* Reset interrupt controller - initialises all registers to 0 */
125 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
126 
127 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
128 
129 	for (; nirq > 0; nirq--, imp++) {
130 		int n = imp->im_irq;
131 
132 		switch (imp->im_type) {
133 		case MSC01_IRQ_EDGE:
134 			irq_set_chip_and_handler_name(irqbase + n,
135 						      &msc_edgeirq_type,
136 						      handle_edge_irq,
137 						      "edge");
138 			if (cpu_has_veic)
139 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
140 			else
141 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
142 			break;
143 		case MSC01_IRQ_LEVEL:
144 			irq_set_chip_and_handler_name(irqbase + n,
145 						      &msc_levelirq_type,
146 						      handle_level_irq,
147 						      "level");
148 			if (cpu_has_veic)
149 				MSCIC_WRITE(MSC01_IC_SUP+n*8, 0);
150 			else
151 				MSCIC_WRITE(MSC01_IC_SUP+n*8, imp->im_lvl);
152 		}
153 	}
154 
155 	irq_base = irqbase;
156 
157 	MSCIC_WRITE(MSC01_IC_GENA, MSC01_IC_GENA_GENA_BIT);	/* Enable interrupt generation */
158 
159 }
160