xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision 87c2ce3b)
1 /*
2  * Copyright (c) 2004 MIPS Inc
3  * Author: chris@mips.com
4  *
5  * This program is free software; you can redistribute  it and/or modify it
6  * under  the terms of  the GNU General  Public License as published by the
7  * Free Software Foundation;  either version 2 of the  License, or (at your
8  * option) any later version.
9  */
10 #include <linux/module.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <asm/ptrace.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 
20 static unsigned long _icctrl_msc;
21 #define MSC01_IC_REG_BASE	_icctrl_msc
22 
23 #define MSCIC_WRITE(reg, data)	do { *(volatile u32 *)(reg) = data; } while (0)
24 #define MSCIC_READ(reg, data)	do { data = *(volatile u32 *)(reg); } while (0)
25 
26 static unsigned int irq_base;
27 
28 /* mask off an interrupt */
29 static inline void mask_msc_irq(unsigned int irq)
30 {
31 	if (irq < (irq_base + 32))
32 		MSCIC_WRITE(MSC01_IC_DISL, 1<<(irq - irq_base));
33 	else
34 		MSCIC_WRITE(MSC01_IC_DISH, 1<<(irq - irq_base - 32));
35 }
36 
37 /* unmask an interrupt */
38 static inline void unmask_msc_irq(unsigned int irq)
39 {
40 	if (irq < (irq_base + 32))
41 		MSCIC_WRITE(MSC01_IC_ENAL, 1<<(irq - irq_base));
42 	else
43 		MSCIC_WRITE(MSC01_IC_ENAH, 1<<(irq - irq_base - 32));
44 }
45 
46 /*
47  * Enables the IRQ on SOC-it
48  */
49 static void enable_msc_irq(unsigned int irq)
50 {
51 	unmask_msc_irq(irq);
52 }
53 
54 /*
55  * Initialize the IRQ on SOC-it
56  */
57 static unsigned int startup_msc_irq(unsigned int irq)
58 {
59 	unmask_msc_irq(irq);
60 	return 0;
61 }
62 
63 /*
64  * Disables the IRQ on SOC-it
65  */
66 static void disable_msc_irq(unsigned int irq)
67 {
68 	mask_msc_irq(irq);
69 }
70 
71 /*
72  * Masks and ACKs an IRQ
73  */
74 static void level_mask_and_ack_msc_irq(unsigned int irq)
75 {
76 	mask_msc_irq(irq);
77 	if (!cpu_has_veic)
78 		MSCIC_WRITE(MSC01_IC_EOI, 0);
79 }
80 
81 /*
82  * Masks and ACKs an IRQ
83  */
84 static void edge_mask_and_ack_msc_irq(unsigned int irq)
85 {
86 	mask_msc_irq(irq);
87 	if (!cpu_has_veic)
88 		MSCIC_WRITE(MSC01_IC_EOI, 0);
89 	else {
90 		u32 r;
91 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
92 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
93 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
94 	}
95 }
96 
97 /*
98  * End IRQ processing
99  */
100 static void end_msc_irq(unsigned int irq)
101 {
102 	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
103 		unmask_msc_irq(irq);
104 }
105 
106 /*
107  * Interrupt handler for interrupts coming from SOC-it.
108  */
109 void ll_msc_irq(struct pt_regs *regs)
110 {
111  	unsigned int irq;
112 
113 	/* read the interrupt vector register */
114 	MSCIC_READ(MSC01_IC_VEC, irq);
115 	if (irq < 64)
116 		do_IRQ(irq + irq_base, regs);
117 	else {
118 		/* Ignore spurious interrupt */
119 	}
120 }
121 
122 void
123 msc_bind_eic_interrupt (unsigned int irq, unsigned int set)
124 {
125 	MSCIC_WRITE(MSC01_IC_RAMW,
126 		    (irq<<MSC01_IC_RAMW_ADDR_SHF) | (set<<MSC01_IC_RAMW_DATA_SHF));
127 }
128 
129 #define shutdown_msc_irq	disable_msc_irq
130 
131 struct hw_interrupt_type msc_levelirq_type = {
132 	.typename = "SOC-it-Level",
133 	.startup = startup_msc_irq,
134 	.shutdown = shutdown_msc_irq,
135 	.enable = enable_msc_irq,
136 	.disable = disable_msc_irq,
137 	.ack = level_mask_and_ack_msc_irq,
138 	.end = end_msc_irq,
139 };
140 
141 struct hw_interrupt_type msc_edgeirq_type = {
142 	.typename = "SOC-it-Edge",
143 	.startup =startup_msc_irq,
144 	.shutdown = shutdown_msc_irq,
145 	.enable = enable_msc_irq,
146 	.disable = disable_msc_irq,
147 	.ack = edge_mask_and_ack_msc_irq,
148 	.end = end_msc_irq,
149 };
150 
151 
152 void __init init_msc_irqs(unsigned int base, msc_irqmap_t *imp, int nirq)
153 {
154 	extern void (*board_bind_eic_interrupt)(unsigned int irq, unsigned int regset);
155 
156 	_icctrl_msc = (unsigned long) ioremap (MIPS_MSC01_IC_REG_BASE, 0x40000);
157 
158 	/* Reset interrupt controller - initialises all registers to 0 */
159 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
160 
161 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
162 
163 	for (; nirq >= 0; nirq--, imp++) {
164 		int n = imp->im_irq;
165 
166 		switch (imp->im_type) {
167 		case MSC01_IRQ_EDGE:
168 			irq_desc[base+n].handler = &msc_edgeirq_type;
169 			if (cpu_has_veic)
170 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
171 			else
172 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
173 			break;
174 		case MSC01_IRQ_LEVEL:
175 			irq_desc[base+n].handler = &msc_levelirq_type;
176 			if (cpu_has_veic)
177 				MSCIC_WRITE(MSC01_IC_SUP+n*8, 0);
178 			else
179 				MSCIC_WRITE(MSC01_IC_SUP+n*8, imp->im_lvl);
180 		}
181 	}
182 
183 	irq_base = base;
184 
185 	MSCIC_WRITE(MSC01_IC_GENA, MSC01_IC_GENA_GENA_BIT);	/* Enable interrupt generation */
186 
187 }
188