xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision d78c317f)
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 	unsigned int irq = d->irq;
57 
58 	mask_msc_irq(d);
59 	if (!cpu_has_veic)
60 		MSCIC_WRITE(MSC01_IC_EOI, 0);
61 	/* This actually needs to be a call into platform code */
62 	smtc_im_ack_irq(irq);
63 }
64 
65 /*
66  * Masks and ACKs an IRQ
67  */
68 static void edge_mask_and_ack_msc_irq(struct irq_data *d)
69 {
70 	unsigned int irq = d->irq;
71 
72 	mask_msc_irq(d);
73 	if (!cpu_has_veic)
74 		MSCIC_WRITE(MSC01_IC_EOI, 0);
75 	else {
76 		u32 r;
77 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
78 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
79 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
80 	}
81 	smtc_im_ack_irq(irq);
82 }
83 
84 /*
85  * Interrupt handler for interrupts coming from SOC-it.
86  */
87 void ll_msc_irq(void)
88 {
89  	unsigned int irq;
90 
91 	/* read the interrupt vector register */
92 	MSCIC_READ(MSC01_IC_VEC, irq);
93 	if (irq < 64)
94 		do_IRQ(irq + irq_base);
95 	else {
96 		/* Ignore spurious interrupt */
97 	}
98 }
99 
100 static void msc_bind_eic_interrupt(int irq, int set)
101 {
102 	MSCIC_WRITE(MSC01_IC_RAMW,
103 		    (irq<<MSC01_IC_RAMW_ADDR_SHF) | (set<<MSC01_IC_RAMW_DATA_SHF));
104 }
105 
106 static struct irq_chip msc_levelirq_type = {
107 	.name = "SOC-it-Level",
108 	.irq_ack = level_mask_and_ack_msc_irq,
109 	.irq_mask = mask_msc_irq,
110 	.irq_mask_ack = level_mask_and_ack_msc_irq,
111 	.irq_unmask = unmask_msc_irq,
112 	.irq_eoi = unmask_msc_irq,
113 };
114 
115 static struct irq_chip msc_edgeirq_type = {
116 	.name = "SOC-it-Edge",
117 	.irq_ack = edge_mask_and_ack_msc_irq,
118 	.irq_mask = mask_msc_irq,
119 	.irq_mask_ack = edge_mask_and_ack_msc_irq,
120 	.irq_unmask = unmask_msc_irq,
121 	.irq_eoi = unmask_msc_irq,
122 };
123 
124 
125 void __init init_msc_irqs(unsigned long icubase, unsigned int irqbase, msc_irqmap_t *imp, int nirq)
126 {
127 	_icctrl_msc = (unsigned long) ioremap(icubase, 0x40000);
128 
129 	/* Reset interrupt controller - initialises all registers to 0 */
130 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
131 
132 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
133 
134 	for (; nirq >= 0; nirq--, imp++) {
135 		int n = imp->im_irq;
136 
137 		switch (imp->im_type) {
138 		case MSC01_IRQ_EDGE:
139 			irq_set_chip_and_handler_name(irqbase + n,
140 						      &msc_edgeirq_type,
141 						      handle_edge_irq,
142 						      "edge");
143 			if (cpu_has_veic)
144 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
145 			else
146 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
147 			break;
148 		case MSC01_IRQ_LEVEL:
149 			irq_set_chip_and_handler_name(irqbase + n,
150 						      &msc_levelirq_type,
151 						      handle_level_irq,
152 						      "level");
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