xref: /openbmc/linux/arch/mips/kernel/irq-msc01.c (revision 99a15348)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *
4  * Copyright (c) 2004 MIPS Inc
5  * Author: chris@mips.com
6  *
7  * Copyright (C) 2004, 06 Ralf Baechle <ralf@linux-mips.org>
8  */
9 #include <linux/interrupt.h>
10 #include <linux/kernel.h>
11 #include <linux/sched.h>
12 #include <linux/kernel_stat.h>
13 #include <asm/io.h>
14 #include <asm/irq.h>
15 #include <asm/msc01_ic.h>
16 #include <asm/traps.h>
17 
18 static unsigned long _icctrl_msc;
19 #define MSC01_IC_REG_BASE	_icctrl_msc
20 
21 #define MSCIC_WRITE(reg, data)	do { *(volatile u32 *)(reg) = data; } while (0)
22 #define MSCIC_READ(reg, data)	do { data = *(volatile u32 *)(reg); } while (0)
23 
24 static unsigned int irq_base;
25 
26 /* mask off an interrupt */
27 static inline void mask_msc_irq(struct irq_data *d)
28 {
29 	unsigned int irq = d->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(struct irq_data *d)
39 {
40 	unsigned int irq = d->irq;
41 
42 	if (irq < (irq_base + 32))
43 		MSCIC_WRITE(MSC01_IC_ENAL, 1<<(irq - irq_base));
44 	else
45 		MSCIC_WRITE(MSC01_IC_ENAH, 1<<(irq - irq_base - 32));
46 }
47 
48 /*
49  * Masks and ACKs an IRQ
50  */
51 static void level_mask_and_ack_msc_irq(struct irq_data *d)
52 {
53 	mask_msc_irq(d);
54 	if (!cpu_has_veic)
55 		MSCIC_WRITE(MSC01_IC_EOI, 0);
56 }
57 
58 /*
59  * Masks and ACKs an IRQ
60  */
61 static void edge_mask_and_ack_msc_irq(struct irq_data *d)
62 {
63 	unsigned int irq = d->irq;
64 
65 	mask_msc_irq(d);
66 	if (!cpu_has_veic)
67 		MSCIC_WRITE(MSC01_IC_EOI, 0);
68 	else {
69 		u32 r;
70 		MSCIC_READ(MSC01_IC_SUP+irq*8, r);
71 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
72 		MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
73 	}
74 }
75 
76 /*
77  * Interrupt handler for interrupts coming from SOC-it.
78  */
79 void ll_msc_irq(void)
80 {
81 	unsigned int irq;
82 
83 	/* read the interrupt vector register */
84 	MSCIC_READ(MSC01_IC_VEC, irq);
85 	if (irq < 64)
86 		do_IRQ(irq + irq_base);
87 	else {
88 		/* Ignore spurious interrupt */
89 	}
90 }
91 
92 static void msc_bind_eic_interrupt(int irq, int set)
93 {
94 	MSCIC_WRITE(MSC01_IC_RAMW,
95 		    (irq<<MSC01_IC_RAMW_ADDR_SHF) | (set<<MSC01_IC_RAMW_DATA_SHF));
96 }
97 
98 static struct irq_chip msc_levelirq_type = {
99 	.name = "SOC-it-Level",
100 	.irq_ack = level_mask_and_ack_msc_irq,
101 	.irq_mask = mask_msc_irq,
102 	.irq_mask_ack = level_mask_and_ack_msc_irq,
103 	.irq_unmask = unmask_msc_irq,
104 	.irq_eoi = unmask_msc_irq,
105 };
106 
107 static struct irq_chip msc_edgeirq_type = {
108 	.name = "SOC-it-Edge",
109 	.irq_ack = edge_mask_and_ack_msc_irq,
110 	.irq_mask = mask_msc_irq,
111 	.irq_mask_ack = edge_mask_and_ack_msc_irq,
112 	.irq_unmask = unmask_msc_irq,
113 	.irq_eoi = unmask_msc_irq,
114 };
115 
116 
117 void __init init_msc_irqs(unsigned long icubase, unsigned int irqbase, msc_irqmap_t *imp, int nirq)
118 {
119 	_icctrl_msc = (unsigned long) ioremap(icubase, 0x40000);
120 
121 	/* Reset interrupt controller - initialises all registers to 0 */
122 	MSCIC_WRITE(MSC01_IC_RST, MSC01_IC_RST_RST_BIT);
123 
124 	board_bind_eic_interrupt = &msc_bind_eic_interrupt;
125 
126 	for (; nirq > 0; nirq--, imp++) {
127 		int n = imp->im_irq;
128 
129 		switch (imp->im_type) {
130 		case MSC01_IRQ_EDGE:
131 			irq_set_chip_and_handler_name(irqbase + n,
132 						      &msc_edgeirq_type,
133 						      handle_edge_irq,
134 						      "edge");
135 			if (cpu_has_veic)
136 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT);
137 			else
138 				MSCIC_WRITE(MSC01_IC_SUP+n*8, MSC01_IC_SUP_EDGE_BIT | imp->im_lvl);
139 			break;
140 		case MSC01_IRQ_LEVEL:
141 			irq_set_chip_and_handler_name(irqbase + n,
142 						      &msc_levelirq_type,
143 						      handle_level_irq,
144 						      "level");
145 			if (cpu_has_veic)
146 				MSCIC_WRITE(MSC01_IC_SUP+n*8, 0);
147 			else
148 				MSCIC_WRITE(MSC01_IC_SUP+n*8, imp->im_lvl);
149 		}
150 	}
151 
152 	irq_base = irqbase;
153 
154 	MSCIC_WRITE(MSC01_IC_GENA, MSC01_IC_GENA_GENA_BIT);	/* Enable interrupt generation */
155 
156 }
157