xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision 41c594ab)
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 #ifdef CONFIG_MIPS_MT_SMTC
80 	/* This actually needs to be a call into platform code */
81 	if (irq_hwmask[irq] & ST0_IM)
82 		set_c0_status(irq_hwmask[irq] & ST0_IM);
83 #endif /* CONFIG_MIPS_MT_SMTC */
84 }
85 
86 /*
87  * Masks and ACKs an IRQ
88  */
89 static void edge_mask_and_ack_msc_irq(unsigned int irq)
90 {
91 	mask_msc_irq(irq);
92 	if (!cpu_has_veic)
93 		MSCIC_WRITE(MSC01_IC_EOI, 0);
94 	else {
95 		u32 r;
96 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
97 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
98 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
99 	}
100 #ifdef CONFIG_MIPS_MT_SMTC
101 	if (irq_hwmask[irq] & ST0_IM)
102 		set_c0_status(irq_hwmask[irq] & ST0_IM);
103 #endif /* CONFIG_MIPS_MT_SMTC */
104 }
105 
106 /*
107  * End IRQ processing
108  */
109 static void end_msc_irq(unsigned int irq)
110 {
111 	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
112 		unmask_msc_irq(irq);
113 }
114 
115 /*
116  * Interrupt handler for interrupts coming from SOC-it.
117  */
118 void ll_msc_irq(struct pt_regs *regs)
119 {
120  	unsigned int irq;
121 
122 	/* read the interrupt vector register */
123 	MSCIC_READ(MSC01_IC_VEC, irq);
124 	if (irq < 64)
125 		do_IRQ(irq + irq_base, regs);
126 	else {
127 		/* Ignore spurious interrupt */
128 	}
129 }
130 
131 void
132 msc_bind_eic_interrupt (unsigned int irq, unsigned int set)
133 {
134 	MSCIC_WRITE(MSC01_IC_RAMW,
135 		    (irq<<MSC01_IC_RAMW_ADDR_SHF) | (set<<MSC01_IC_RAMW_DATA_SHF));
136 }
137 
138 #define shutdown_msc_irq	disable_msc_irq
139 
140 struct hw_interrupt_type msc_levelirq_type = {
141 	.typename = "SOC-it-Level",
142 	.startup = startup_msc_irq,
143 	.shutdown = shutdown_msc_irq,
144 	.enable = enable_msc_irq,
145 	.disable = disable_msc_irq,
146 	.ack = level_mask_and_ack_msc_irq,
147 	.end = end_msc_irq,
148 };
149 
150 struct hw_interrupt_type msc_edgeirq_type = {
151 	.typename = "SOC-it-Edge",
152 	.startup =startup_msc_irq,
153 	.shutdown = shutdown_msc_irq,
154 	.enable = enable_msc_irq,
155 	.disable = disable_msc_irq,
156 	.ack = edge_mask_and_ack_msc_irq,
157 	.end = end_msc_irq,
158 };
159 
160 
161 void __init init_msc_irqs(unsigned int base, msc_irqmap_t *imp, int nirq)
162 {
163 	extern void (*board_bind_eic_interrupt)(unsigned int irq, unsigned int regset);
164 
165 	_icctrl_msc = (unsigned long) ioremap (MIPS_MSC01_IC_REG_BASE, 0x40000);
166 
167 	/* Reset interrupt controller - initialises all registers to 0 */
168 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
169 
170 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
171 
172 	for (; nirq >= 0; nirq--, imp++) {
173 		int n = imp->im_irq;
174 
175 		switch (imp->im_type) {
176 		case MSC01_IRQ_EDGE:
177 			irq_desc[base+n].handler = &msc_edgeirq_type;
178 			if (cpu_has_veic)
179 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
180 			else
181 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
182 			break;
183 		case MSC01_IRQ_LEVEL:
184 			irq_desc[base+n].handler = &msc_levelirq_type;
185 			if (cpu_has_veic)
186 				MSCIC_WRITE(MSC01_IC_SUP+n*8, 0);
187 			else
188 				MSCIC_WRITE(MSC01_IC_SUP+n*8, imp->im_lvl);
189 		}
190 	}
191 
192 	irq_base = base;
193 
194 	MSCIC_WRITE(MSC01_IC_GENA, MSC01_IC_GENA_GENA_BIT);	/* Enable interrupt generation */
195 
196 }
197