1/*
2 * intc.c -- interrupt controller or ColdFire 5272 SoC
3 *
4 * (C) Copyright 2009, Greg Ungerer <gerg@snapgear.com>
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file COPYING in the main directory of this archive
8 * for more details.
9 */
10
11#include <linux/types.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/interrupt.h>
15#include <linux/kernel_stat.h>
16#include <linux/irq.h>
17#include <linux/io.h>
18#include <asm/coldfire.h>
19#include <asm/mcfsim.h>
20#include <asm/traps.h>
21
22/*
23 * The 5272 ColdFire interrupt controller is nothing like any other
24 * ColdFire interrupt controller - it truly is completely different.
25 * Given its age it is unlikely to be used on any other ColdFire CPU.
26 */
27
28/*
29 * The masking and priproty setting of interrupts on the 5272 is done
30 * via a set of 4 "Interrupt Controller Registers" (ICR). There is a
31 * loose mapping of vector number to register and internal bits, but
32 * a table is the easiest and quickest way to map them.
33 *
34 * Note that the external interrupts are edge triggered (unlike the
35 * internal interrupt sources which are level triggered). Which means
36 * they also need acknowledging via acknowledge bits.
37 */
38struct irqmap {
39 unsigned int icr;
40 unsigned char index;
41 unsigned char ack;
42};
43
44static struct irqmap intc_irqmap[MCFINT_VECMAX - MCFINT_VECBASE] = {
45 /*MCF_IRQ_SPURIOUS*/ { .icr = 0, .index = 0, .ack = 0, },
46 /*MCF_IRQ_EINT1*/ { .icr = MCFSIM_ICR1, .index = 28, .ack = 1, },
47 /*MCF_IRQ_EINT2*/ { .icr = MCFSIM_ICR1, .index = 24, .ack = 1, },
48 /*MCF_IRQ_EINT3*/ { .icr = MCFSIM_ICR1, .index = 20, .ack = 1, },
49 /*MCF_IRQ_EINT4*/ { .icr = MCFSIM_ICR1, .index = 16, .ack = 1, },
50 /*MCF_IRQ_TIMER1*/ { .icr = MCFSIM_ICR1, .index = 12, .ack = 0, },
51 /*MCF_IRQ_TIMER2*/ { .icr = MCFSIM_ICR1, .index = 8, .ack = 0, },
52 /*MCF_IRQ_TIMER3*/ { .icr = MCFSIM_ICR1, .index = 4, .ack = 0, },
53 /*MCF_IRQ_TIMER4*/ { .icr = MCFSIM_ICR1, .index = 0, .ack = 0, },
54 /*MCF_IRQ_UART1*/ { .icr = MCFSIM_ICR2, .index = 28, .ack = 0, },
55 /*MCF_IRQ_UART2*/ { .icr = MCFSIM_ICR2, .index = 24, .ack = 0, },
56 /*MCF_IRQ_PLIP*/ { .icr = MCFSIM_ICR2, .index = 20, .ack = 0, },
57 /*MCF_IRQ_PLIA*/ { .icr = MCFSIM_ICR2, .index = 16, .ack = 0, },
58 /*MCF_IRQ_USB0*/ { .icr = MCFSIM_ICR2, .index = 12, .ack = 0, },
59 /*MCF_IRQ_USB1*/ { .icr = MCFSIM_ICR2, .index = 8, .ack = 0, },
60 /*MCF_IRQ_USB2*/ { .icr = MCFSIM_ICR2, .index = 4, .ack = 0, },
61 /*MCF_IRQ_USB3*/ { .icr = MCFSIM_ICR2, .index = 0, .ack = 0, },
62 /*MCF_IRQ_USB4*/ { .icr = MCFSIM_ICR3, .index = 28, .ack = 0, },
63 /*MCF_IRQ_USB5*/ { .icr = MCFSIM_ICR3, .index = 24, .ack = 0, },
64 /*MCF_IRQ_USB6*/ { .icr = MCFSIM_ICR3, .index = 20, .ack = 0, },
65 /*MCF_IRQ_USB7*/ { .icr = MCFSIM_ICR3, .index = 16, .ack = 0, },
66 /*MCF_IRQ_DMA*/ { .icr = MCFSIM_ICR3, .index = 12, .ack = 0, },
67 /*MCF_IRQ_ERX*/ { .icr = MCFSIM_ICR3, .index = 8, .ack = 0, },
68 /*MCF_IRQ_ETX*/ { .icr = MCFSIM_ICR3, .index = 4, .ack = 0, },
69 /*MCF_IRQ_ENTC*/ { .icr = MCFSIM_ICR3, .index = 0, .ack = 0, },
70 /*MCF_IRQ_QSPI*/ { .icr = MCFSIM_ICR4, .index = 28, .ack = 0, },
71 /*MCF_IRQ_EINT5*/ { .icr = MCFSIM_ICR4, .index = 24, .ack = 1, },
72 /*MCF_IRQ_EINT6*/ { .icr = MCFSIM_ICR4, .index = 20, .ack = 1, },
73 /*MCF_IRQ_SWTO*/ { .icr = MCFSIM_ICR4, .index = 16, .ack = 0, },
74};
75
76/*
77 * The act of masking the interrupt also has a side effect of 'ack'ing
78 * an interrupt on this irq (for the external irqs). So this mask function
79 * is also an ack_mask function.
80 */
81static void intc_irq_mask(struct irq_data *d)
82{
83 unsigned int irq = d->irq;
84
85 if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
86 u32 v;
87 irq -= MCFINT_VECBASE;
88 v = 0x8 << intc_irqmap[irq].index;
89 writel(val: v, addr: intc_irqmap[irq].icr);
90 }
91}
92
93static void intc_irq_unmask(struct irq_data *d)
94{
95 unsigned int irq = d->irq;
96
97 if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
98 u32 v;
99 irq -= MCFINT_VECBASE;
100 v = 0xd << intc_irqmap[irq].index;
101 writel(val: v, addr: intc_irqmap[irq].icr);
102 }
103}
104
105static void intc_irq_ack(struct irq_data *d)
106{
107 unsigned int irq = d->irq;
108
109 /* Only external interrupts are acked */
110 if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
111 irq -= MCFINT_VECBASE;
112 if (intc_irqmap[irq].ack) {
113 u32 v;
114 v = readl(addr: intc_irqmap[irq].icr);
115 v &= (0x7 << intc_irqmap[irq].index);
116 v |= (0x8 << intc_irqmap[irq].index);
117 writel(val: v, addr: intc_irqmap[irq].icr);
118 }
119 }
120}
121
122static int intc_irq_set_type(struct irq_data *d, unsigned int type)
123{
124 unsigned int irq = d->irq;
125
126 if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
127 irq -= MCFINT_VECBASE;
128 if (intc_irqmap[irq].ack) {
129 u32 v;
130 v = readl(MCFSIM_PITR);
131 if (type == IRQ_TYPE_EDGE_FALLING)
132 v &= ~(0x1 << (32 - irq));
133 else
134 v |= (0x1 << (32 - irq));
135 writel(v, MCFSIM_PITR);
136 }
137 }
138 return 0;
139}
140
141/*
142 * Simple flow handler to deal with the external edge triggered interrupts.
143 * We need to be careful with the masking/acking due to the side effects
144 * of masking an interrupt.
145 */
146static void intc_external_irq(struct irq_desc *desc)
147{
148 irq_desc_get_chip(desc)->irq_ack(&desc->irq_data);
149 handle_simple_irq(desc);
150}
151
152static struct irq_chip intc_irq_chip = {
153 .name = "CF-INTC",
154 .irq_mask = intc_irq_mask,
155 .irq_unmask = intc_irq_unmask,
156 .irq_mask_ack = intc_irq_mask,
157 .irq_ack = intc_irq_ack,
158 .irq_set_type = intc_irq_set_type,
159};
160
161void __init init_IRQ(void)
162{
163 int irq, edge;
164
165 /* Mask all interrupt sources */
166 writel(0x88888888, MCFSIM_ICR1);
167 writel(0x88888888, MCFSIM_ICR2);
168 writel(0x88888888, MCFSIM_ICR3);
169 writel(0x88888888, MCFSIM_ICR4);
170
171 for (irq = 0; (irq < NR_IRQS); irq++) {
172 irq_set_chip(irq, chip: &intc_irq_chip);
173 edge = 0;
174 if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX))
175 edge = intc_irqmap[irq - MCFINT_VECBASE].ack;
176 if (edge) {
177 irq_set_irq_type(irq, type: IRQ_TYPE_EDGE_RISING);
178 irq_set_handler(irq, handle: intc_external_irq);
179 } else {
180 irq_set_irq_type(irq, type: IRQ_TYPE_LEVEL_HIGH);
181 irq_set_handler(irq, handle: handle_level_irq);
182 }
183 }
184}
185
186

source code of linux/arch/m68k/coldfire/intc-5272.c