1 /*
2  * intc-2.c
3  *
4  * General interrupt controller code for the many ColdFire cores that use
5  * interrupt controllers with 63 interrupt sources, organized as 56 fully-
6  * programmable + 7 fixed-level interrupt sources. This includes the 523x
7  * family, the 5270, 5271, 5274, 5275, and the 528x family which have two such
8  * controllers, and the 547x and 548x families which have only one of them.
9  *
10  * The external 7 fixed interrupts are part the the Edge Port unit of these
11  * ColdFire parts. They can be configured as level or edge triggered.
12  *
13  * (C) Copyright 2009-2011, Greg Ungerer <gerg@snapgear.com>
14  *
15  * This file is subject to the terms and conditions of the GNU General Public
16  * License.  See the file COPYING in the main directory of this archive
17  * for more details.
18  */
19 
20 #include <linux/types.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/interrupt.h>
24 #include <linux/irq.h>
25 #include <linux/io.h>
26 #include <asm/coldfire.h>
27 #include <asm/mcfsim.h>
28 #include <asm/traps.h>
29 
30 /*
31  * Bit definitions for the ICR family of registers.
32  */
33 #define MCFSIM_ICR_LEVEL(l)	((l)<<3)	/* Level l intr */
34 #define MCFSIM_ICR_PRI(p)	(p)		/* Priority p intr */
35 
36 /*
37  *	The EDGE Port interrupts are the fixed 7 external interrupts.
38  *	They need some special treatment, for example they need to be acked.
39  */
40 #define	EINT0	64	/* Is not actually used, but spot reserved for it */
41 #define	EINT1	65	/* EDGE Port interrupt 1 */
42 #define	EINT7	71	/* EDGE Port interrupt 7 */
43 
44 #ifdef MCFICM_INTC1
45 #define NR_VECS	128
46 #else
47 #define NR_VECS	64
48 #endif
49 
intc_irq_mask(struct irq_data * d)50 static void intc_irq_mask(struct irq_data *d)
51 {
52 	unsigned int irq = d->irq - MCFINT_VECBASE;
53 	unsigned long imraddr;
54 	u32 val, imrbit;
55 
56 #ifdef MCFICM_INTC1
57 	imraddr = (irq & 0x40) ? MCFICM_INTC1 : MCFICM_INTC0;
58 #else
59 	imraddr = MCFICM_INTC0;
60 #endif
61 	imraddr += (irq & 0x20) ? MCFINTC_IMRH : MCFINTC_IMRL;
62 	imrbit = 0x1 << (irq & 0x1f);
63 
64 	val = __raw_readl(imraddr);
65 	__raw_writel(val | imrbit, imraddr);
66 }
67 
intc_irq_unmask(struct irq_data * d)68 static void intc_irq_unmask(struct irq_data *d)
69 {
70 	unsigned int irq = d->irq - MCFINT_VECBASE;
71 	unsigned long imraddr;
72 	u32 val, imrbit;
73 
74 #ifdef MCFICM_INTC1
75 	imraddr = (irq & 0x40) ? MCFICM_INTC1 : MCFICM_INTC0;
76 #else
77 	imraddr = MCFICM_INTC0;
78 #endif
79 	imraddr += ((irq & 0x20) ? MCFINTC_IMRH : MCFINTC_IMRL);
80 	imrbit = 0x1 << (irq & 0x1f);
81 
82 	/* Don't set the "maskall" bit! */
83 	if ((irq & 0x20) == 0)
84 		imrbit |= 0x1;
85 
86 	val = __raw_readl(imraddr);
87 	__raw_writel(val & ~imrbit, imraddr);
88 }
89 
90 /*
91  *	Only the external (or EDGE Port) interrupts need to be acknowledged
92  *	here, as part of the IRQ handler. They only really need to be ack'ed
93  *	if they are in edge triggered mode, but there is no harm in doing it
94  *	for all types.
95  */
intc_irq_ack(struct irq_data * d)96 static void intc_irq_ack(struct irq_data *d)
97 {
98 	unsigned int irq = d->irq;
99 
100 	__raw_writeb(0x1 << (irq - EINT0), MCFEPORT_EPFR);
101 }
102 
103 /*
104  *	Each vector needs a unique priority and level associated with it.
105  *	We don't really care so much what they are, we don't rely on the
106  *	traditional priority interrupt scheme of the m68k/ColdFire. This
107  *	only needs to be set once for an interrupt, and we will never change
108  *	these values once we have set them.
109  */
110 static u8 intc_intpri = MCFSIM_ICR_LEVEL(6) | MCFSIM_ICR_PRI(6);
111 
intc_irq_startup(struct irq_data * d)112 static unsigned int intc_irq_startup(struct irq_data *d)
113 {
114 	unsigned int irq = d->irq - MCFINT_VECBASE;
115 	unsigned long icraddr;
116 
117 #ifdef MCFICM_INTC1
118 	icraddr = (irq & 0x40) ? MCFICM_INTC1 : MCFICM_INTC0;
119 #else
120 	icraddr = MCFICM_INTC0;
121 #endif
122 	icraddr += MCFINTC_ICR0 + (irq & 0x3f);
123 	if (__raw_readb(icraddr) == 0)
124 		__raw_writeb(intc_intpri--, icraddr);
125 
126 	irq = d->irq;
127 	if ((irq >= EINT1) && (irq <= EINT7)) {
128 		u8 v;
129 
130 		irq -= EINT0;
131 
132 		/* Set EPORT line as input */
133 		v = __raw_readb(MCFEPORT_EPDDR);
134 		__raw_writeb(v & ~(0x1 << irq), MCFEPORT_EPDDR);
135 
136 		/* Set EPORT line as interrupt source */
137 		v = __raw_readb(MCFEPORT_EPIER);
138 		__raw_writeb(v | (0x1 << irq), MCFEPORT_EPIER);
139 	}
140 
141 	intc_irq_unmask(d);
142 	return 0;
143 }
144 
intc_irq_set_type(struct irq_data * d,unsigned int type)145 static int intc_irq_set_type(struct irq_data *d, unsigned int type)
146 {
147 	unsigned int irq = d->irq;
148 	u16 pa, tb;
149 
150 	switch (type) {
151 	case IRQ_TYPE_EDGE_RISING:
152 		tb = 0x1;
153 		break;
154 	case IRQ_TYPE_EDGE_FALLING:
155 		tb = 0x2;
156 		break;
157 	case IRQ_TYPE_EDGE_BOTH:
158 		tb = 0x3;
159 		break;
160 	default:
161 		/* Level triggered */
162 		tb = 0;
163 		break;
164 	}
165 
166 	if (tb)
167 		irq_set_handler(irq, handle_edge_irq);
168 
169 	irq -= EINT0;
170 	pa = __raw_readw(MCFEPORT_EPPAR);
171 	pa = (pa & ~(0x3 << (irq * 2))) | (tb << (irq * 2));
172 	__raw_writew(pa, MCFEPORT_EPPAR);
173 
174 	return 0;
175 }
176 
177 static struct irq_chip intc_irq_chip = {
178 	.name		= "CF-INTC",
179 	.irq_startup	= intc_irq_startup,
180 	.irq_mask	= intc_irq_mask,
181 	.irq_unmask	= intc_irq_unmask,
182 };
183 
184 static struct irq_chip intc_irq_chip_edge_port = {
185 	.name		= "CF-INTC-EP",
186 	.irq_startup	= intc_irq_startup,
187 	.irq_mask	= intc_irq_mask,
188 	.irq_unmask	= intc_irq_unmask,
189 	.irq_ack	= intc_irq_ack,
190 	.irq_set_type	= intc_irq_set_type,
191 };
192 
init_IRQ(void)193 void __init init_IRQ(void)
194 {
195 	int irq;
196 
197 	/* Mask all interrupt sources */
198 	__raw_writel(0x1, MCFICM_INTC0 + MCFINTC_IMRL);
199 #ifdef MCFICM_INTC1
200 	__raw_writel(0x1, MCFICM_INTC1 + MCFINTC_IMRL);
201 #endif
202 
203 	for (irq = MCFINT_VECBASE; (irq < MCFINT_VECBASE + NR_VECS); irq++) {
204 		if ((irq >= EINT1) && (irq <=EINT7))
205 			irq_set_chip(irq, &intc_irq_chip_edge_port);
206 		else
207 			irq_set_chip(irq, &intc_irq_chip);
208 		irq_set_irq_type(irq, IRQ_TYPE_LEVEL_HIGH);
209 		irq_set_handler(irq, handle_level_irq);
210 	}
211 }
212 
213