xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision a1e58bbd)
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 
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(unsigned int irq)
31 {
32 	if (irq < (irq_base + 32))
33 		MSCIC_WRITE(MSC01_IC_DISL, 1<<(irq - irq_base));
34 	else
35 		MSCIC_WRITE(MSC01_IC_DISH, 1<<(irq - irq_base - 32));
36 }
37 
38 /* unmask an interrupt */
39 static inline void unmask_msc_irq(unsigned int irq)
40 {
41 	if (irq < (irq_base + 32))
42 		MSCIC_WRITE(MSC01_IC_ENAL, 1<<(irq - irq_base));
43 	else
44 		MSCIC_WRITE(MSC01_IC_ENAH, 1<<(irq - irq_base - 32));
45 }
46 
47 /*
48  * Masks and ACKs an IRQ
49  */
50 static void level_mask_and_ack_msc_irq(unsigned int irq)
51 {
52 	mask_msc_irq(irq);
53 	if (!cpu_has_veic)
54 		MSCIC_WRITE(MSC01_IC_EOI, 0);
55 	/* This actually needs to be a call into platform code */
56 	smtc_im_ack_irq(irq);
57 }
58 
59 /*
60  * Masks and ACKs an IRQ
61  */
62 static void edge_mask_and_ack_msc_irq(unsigned int irq)
63 {
64 	mask_msc_irq(irq);
65 	if (!cpu_has_veic)
66 		MSCIC_WRITE(MSC01_IC_EOI, 0);
67 	else {
68 		u32 r;
69 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
70 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
71 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
72 	}
73 	smtc_im_ack_irq(irq);
74 }
75 
76 /*
77  * End IRQ processing
78  */
79 static void end_msc_irq(unsigned int irq)
80 {
81 	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
82 		unmask_msc_irq(irq);
83 }
84 
85 /*
86  * Interrupt handler for interrupts coming from SOC-it.
87  */
88 void ll_msc_irq(void)
89 {
90  	unsigned int irq;
91 
92 	/* read the interrupt vector register */
93 	MSCIC_READ(MSC01_IC_VEC, irq);
94 	if (irq < 64)
95 		do_IRQ(irq + irq_base);
96 	else {
97 		/* Ignore spurious interrupt */
98 	}
99 }
100 
101 void
102 msc_bind_eic_interrupt(unsigned int irq, unsigned 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 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 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 	extern void (*board_bind_eic_interrupt)(unsigned int irq, unsigned int regset);
132 
133 	_icctrl_msc = (unsigned long) ioremap(icubase, 0x40000);
134 
135 	/* Reset interrupt controller - initialises all registers to 0 */
136 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
137 
138 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
139 
140 	for (; nirq >= 0; nirq--, imp++) {
141 		int n = imp->im_irq;
142 
143 		switch (imp->im_type) {
144 		case MSC01_IRQ_EDGE:
145 			set_irq_chip(irqbase+n, &msc_edgeirq_type);
146 			if (cpu_has_veic)
147 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
148 			else
149 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
150 			break;
151 		case MSC01_IRQ_LEVEL:
152 			set_irq_chip(irqbase+n, &msc_levelirq_type);
153 			if (cpu_has_veic)
154 				MSCIC_WRITE(MSC01_IC_SUP+n*8, 0);
155 			else
156 				MSCIC_WRITE(MSC01_IC_SUP+n*8, imp->im_lvl);
157 		}
158 	}
159 
160 	irq_base = irqbase;
161 
162 	MSCIC_WRITE(MSC01_IC_GENA, MSC01_IC_GENA_GENA_BIT);	/* Enable interrupt generation */
163 
164 }
165