1 /*
2  * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3  * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
17  * MA  02110-1301, USA.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/irq.h>
22 #include <linux/io.h>
23 #include <mach/common.h>
24 #include <asm/mach/irq.h>
25 #include <mach/hardware.h>
26 
27 #include "irq-common.h"
28 
29 #define AVIC_INTCNTL		0x00	/* int control reg */
30 #define AVIC_NIMASK		0x04	/* int mask reg */
31 #define AVIC_INTENNUM		0x08	/* int enable number reg */
32 #define AVIC_INTDISNUM		0x0C	/* int disable number reg */
33 #define AVIC_INTENABLEH		0x10	/* int enable reg high */
34 #define AVIC_INTENABLEL		0x14	/* int enable reg low */
35 #define AVIC_INTTYPEH		0x18	/* int type reg high */
36 #define AVIC_INTTYPEL		0x1C	/* int type reg low */
37 #define AVIC_NIPRIORITY(x)	(0x20 + 4 * (7 - (x))) /* int priority */
38 #define AVIC_NIVECSR		0x40	/* norm int vector/status */
39 #define AVIC_FIVECSR		0x44	/* fast int vector/status */
40 #define AVIC_INTSRCH		0x48	/* int source reg high */
41 #define AVIC_INTSRCL		0x4C	/* int source reg low */
42 #define AVIC_INTFRCH		0x50	/* int force reg high */
43 #define AVIC_INTFRCL		0x54	/* int force reg low */
44 #define AVIC_NIPNDH		0x58	/* norm int pending high */
45 #define AVIC_NIPNDL		0x5C	/* norm int pending low */
46 #define AVIC_FIPNDH		0x60	/* fast int pending high */
47 #define AVIC_FIPNDL		0x64	/* fast int pending low */
48 
49 void __iomem *avic_base;
50 
51 #ifdef CONFIG_MXC_IRQ_PRIOR
avic_irq_set_priority(unsigned char irq,unsigned char prio)52 static int avic_irq_set_priority(unsigned char irq, unsigned char prio)
53 {
54 	unsigned int temp;
55 	unsigned int mask = 0x0F << irq % 8 * 4;
56 
57 	if (irq >= MXC_INTERNAL_IRQS)
58 		return -EINVAL;;
59 
60 	temp = __raw_readl(avic_base + AVIC_NIPRIORITY(irq / 8));
61 	temp &= ~mask;
62 	temp |= prio & mask;
63 
64 	__raw_writel(temp, avic_base + AVIC_NIPRIORITY(irq / 8));
65 
66 	return 0;
67 }
68 #endif
69 
70 #ifdef CONFIG_FIQ
avic_set_irq_fiq(unsigned int irq,unsigned int type)71 static int avic_set_irq_fiq(unsigned int irq, unsigned int type)
72 {
73 	unsigned int irqt;
74 
75 	if (irq >= MXC_INTERNAL_IRQS)
76 		return -EINVAL;
77 
78 	if (irq < MXC_INTERNAL_IRQS / 2) {
79 		irqt = __raw_readl(avic_base + AVIC_INTTYPEL) & ~(1 << irq);
80 		__raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEL);
81 	} else {
82 		irq -= MXC_INTERNAL_IRQS / 2;
83 		irqt = __raw_readl(avic_base + AVIC_INTTYPEH) & ~(1 << irq);
84 		__raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEH);
85 	}
86 
87 	return 0;
88 }
89 #endif /* CONFIG_FIQ */
90 
91 /* Disable interrupt number "irq" in the AVIC */
mxc_mask_irq(struct irq_data * d)92 static void mxc_mask_irq(struct irq_data *d)
93 {
94 	__raw_writel(d->irq, avic_base + AVIC_INTDISNUM);
95 }
96 
97 /* Enable interrupt number "irq" in the AVIC */
mxc_unmask_irq(struct irq_data * d)98 static void mxc_unmask_irq(struct irq_data *d)
99 {
100 	__raw_writel(d->irq, avic_base + AVIC_INTENNUM);
101 }
102 
103 static struct mxc_irq_chip mxc_avic_chip = {
104 	.base = {
105 		.irq_ack = mxc_mask_irq,
106 		.irq_mask = mxc_mask_irq,
107 		.irq_unmask = mxc_unmask_irq,
108 	},
109 #ifdef CONFIG_MXC_IRQ_PRIOR
110 	.set_priority = avic_irq_set_priority,
111 #endif
112 #ifdef CONFIG_FIQ
113 	.set_irq_fiq = avic_set_irq_fiq,
114 #endif
115 };
116 
117 /*
118  * This function initializes the AVIC hardware and disables all the
119  * interrupts. It registers the interrupt enable and disable functions
120  * to the kernel for each interrupt source.
121  */
mxc_init_irq(void __iomem * irqbase)122 void __init mxc_init_irq(void __iomem *irqbase)
123 {
124 	int i;
125 
126 	avic_base = irqbase;
127 
128 	/* put the AVIC into the reset value with
129 	 * all interrupts disabled
130 	 */
131 	__raw_writel(0, avic_base + AVIC_INTCNTL);
132 	__raw_writel(0x1f, avic_base + AVIC_NIMASK);
133 
134 	/* disable all interrupts */
135 	__raw_writel(0, avic_base + AVIC_INTENABLEH);
136 	__raw_writel(0, avic_base + AVIC_INTENABLEL);
137 
138 	/* all IRQ no FIQ */
139 	__raw_writel(0, avic_base + AVIC_INTTYPEH);
140 	__raw_writel(0, avic_base + AVIC_INTTYPEL);
141 	for (i = 0; i < MXC_INTERNAL_IRQS; i++) {
142 		irq_set_chip_and_handler(i, &mxc_avic_chip.base,
143 					 handle_level_irq);
144 		set_irq_flags(i, IRQF_VALID);
145 	}
146 
147 	/* Set default priority value (0) for all IRQ's */
148 	for (i = 0; i < 8; i++)
149 		__raw_writel(0, avic_base + AVIC_NIPRIORITY(i));
150 
151 #ifdef CONFIG_FIQ
152 	/* Initialize FIQ */
153 	init_FIQ();
154 #endif
155 
156 	printk(KERN_INFO "MXC IRQ initialized\n");
157 }
158 
159