summaryrefslogtreecommitdiff
path: root/arch/m68k/platform/5272/intc.c
blob: 43e6e96f087f618005d60161be489c589dc956a2 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/*
 * intc.c  --  interrupt controller or ColdFire 5272 SoC
 *
 * (C) Copyright 2009, Greg Ungerer <gerg@snapgear.com>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 */

#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/traps.h>

/*
 * The 5272 ColdFire interrupt controller is nothing like any other
 * ColdFire interrupt controller - it truly is completely different.
 * Given its age it is unlikely to be used on any other ColdFire CPU.
 */

/*
 * The masking and priproty setting of interrupts on the 5272 is done
 * via a set of 4 "Interrupt Controller Registers" (ICR). There is a
 * loose mapping of vector number to register and internal bits, but
 * a table is the easiest and quickest way to map them.
 *
 * Note that the external interrupts are edge triggered (unlike the
 * internal interrupt sources which are level triggered). Which means
 * they also need acknowledgeing via acknowledge bits.
 */
struct irqmap {
	unsigned char	icr;
	unsigned char	index;
	unsigned char	ack;
};

static struct irqmap intc_irqmap[MCFINT_VECMAX - MCFINT_VECBASE] = {
	/*MCF_IRQ_SPURIOUS*/	{ .icr = 0,           .index = 0,  .ack = 0, },
	/*MCF_IRQ_EINT1*/	{ .icr = MCFSIM_ICR1, .index = 28, .ack = 1, },
	/*MCF_IRQ_EINT2*/	{ .icr = MCFSIM_ICR1, .index = 24, .ack = 1, },
	/*MCF_IRQ_EINT3*/	{ .icr = MCFSIM_ICR1, .index = 20, .ack = 1, },
	/*MCF_IRQ_EINT4*/	{ .icr = MCFSIM_ICR1, .index = 16, .ack = 1, },
	/*MCF_IRQ_TIMER1*/	{ .icr = MCFSIM_ICR1, .index = 12, .ack = 0, },
	/*MCF_IRQ_TIMER2*/	{ .icr = MCFSIM_ICR1, .index = 8,  .ack = 0, },
	/*MCF_IRQ_TIMER3*/	{ .icr = MCFSIM_ICR1, .index = 4,  .ack = 0, },
	/*MCF_IRQ_TIMER4*/	{ .icr = MCFSIM_ICR1, .index = 0,  .ack = 0, },
	/*MCF_IRQ_UART1*/	{ .icr = MCFSIM_ICR2, .index = 28, .ack = 0, },
	/*MCF_IRQ_UART2*/	{ .icr = MCFSIM_ICR2, .index = 24, .ack = 0, },
	/*MCF_IRQ_PLIP*/	{ .icr = MCFSIM_ICR2, .index = 20, .ack = 0, },
	/*MCF_IRQ_PLIA*/	{ .icr = MCFSIM_ICR2, .index = 16, .ack = 0, },
	/*MCF_IRQ_USB0*/	{ .icr = MCFSIM_ICR2, .index = 12, .ack = 0, },
	/*MCF_IRQ_USB1*/	{ .icr = MCFSIM_ICR2, .index = 8,  .ack = 0, },
	/*MCF_IRQ_USB2*/	{ .icr = MCFSIM_ICR2, .index = 4,  .ack = 0, },
	/*MCF_IRQ_USB3*/	{ .icr = MCFSIM_ICR2, .index = 0,  .ack = 0, },
	/*MCF_IRQ_USB4*/	{ .icr = MCFSIM_ICR3, .index = 28, .ack = 0, },
	/*MCF_IRQ_USB5*/	{ .icr = MCFSIM_ICR3, .index = 24, .ack = 0, },
	/*MCF_IRQ_USB6*/	{ .icr = MCFSIM_ICR3, .index = 20, .ack = 0, },
	/*MCF_IRQ_USB7*/	{ .icr = MCFSIM_ICR3, .index = 16, .ack = 0, },
	/*MCF_IRQ_DMA*/		{ .icr = MCFSIM_ICR3, .index = 12, .ack = 0, },
	/*MCF_IRQ_ERX*/		{ .icr = MCFSIM_ICR3, .index = 8,  .ack = 0, },
	/*MCF_IRQ_ETX*/		{ .icr = MCFSIM_ICR3, .index = 4,  .ack = 0, },
	/*MCF_IRQ_ENTC*/	{ .icr = MCFSIM_ICR3, .index = 0,  .ack = 0, },
	/*MCF_IRQ_QSPI*/	{ .icr = MCFSIM_ICR4, .index = 28, .ack = 0, },
	/*MCF_IRQ_EINT5*/	{ .icr = MCFSIM_ICR4, .index = 24, .ack = 1, },
	/*MCF_IRQ_EINT6*/	{ .icr = MCFSIM_ICR4, .index = 20, .ack = 1, },
	/*MCF_IRQ_SWTO*/	{ .icr = MCFSIM_ICR4, .index = 16, .ack = 0, },
};

/*
 * The act of masking the interrupt also has a side effect of 'ack'ing
 * an interrupt on this irq (for the external irqs). So this mask function
 * is also an ack_mask function.
 */
static void intc_irq_mask(struct irq_data *d)
{
	unsigned int irq = d->irq;

	if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
		u32 v;
		irq -= MCFINT_VECBASE;
		v = 0x8 << intc_irqmap[irq].index;
		writel(v, MCF_MBAR + intc_irqmap[irq].icr);
	}
}

static void intc_irq_unmask(struct irq_data *d)
{
	unsigned int irq = d->irq;

	if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
		u32 v;
		irq -= MCFINT_VECBASE;
		v = 0xd << intc_irqmap[irq].index;
		writel(v, MCF_MBAR + intc_irqmap[irq].icr);
	}
}

static void intc_irq_ack(struct irq_data *d)
{
	unsigned int irq = d->irq;

	/* Only external interrupts are acked */
	if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
		irq -= MCFINT_VECBASE;
		if (intc_irqmap[irq].ack) {
			u32 v;
			v = readl(MCF_MBAR + intc_irqmap[irq].icr);
			v &= (0x7 << intc_irqmap[irq].index);
			v |= (0x8 << intc_irqmap[irq].index);
			writel(v, MCF_MBAR + intc_irqmap[irq].icr);
		}
	}
}

static int intc_irq_set_type(struct irq_data *d, unsigned int type)
{
	unsigned int irq = d->irq;

	if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX)) {
		irq -= MCFINT_VECBASE;
		if (intc_irqmap[irq].ack) {
			u32 v;
			v = readl(MCF_MBAR + MCFSIM_PITR);
			if (type == IRQ_TYPE_EDGE_FALLING)
				v &= ~(0x1 << (32 - irq));
			else
				v |= (0x1 << (32 - irq));
			writel(v, MCF_MBAR + MCFSIM_PITR);
		}
	}
	return 0;
}

/*
 * Simple flow handler to deal with the external edge triggered interrupts.
 * We need to be careful with the masking/acking due to the side effects
 * of masking an interrupt.
 */
static void intc_external_irq(unsigned int irq, struct irq_desc *desc)
{
	irq_desc_get_chip(desc)->irq_ack(&desc->irq_data);
	handle_simple_irq(irq, desc);
}

static struct irq_chip intc_irq_chip = {
	.name		= "CF-INTC",
	.irq_mask	= intc_irq_mask,
	.irq_unmask	= intc_irq_unmask,
	.irq_mask_ack	= intc_irq_mask,
	.irq_ack	= intc_irq_ack,
	.irq_set_type	= intc_irq_set_type,
};

void __init init_IRQ(void)
{
	int irq, edge;

	init_vectors();

	/* Mask all interrupt sources */
	writel(0x88888888, MCF_MBAR + MCFSIM_ICR1);
	writel(0x88888888, MCF_MBAR + MCFSIM_ICR2);
	writel(0x88888888, MCF_MBAR + MCFSIM_ICR3);
	writel(0x88888888, MCF_MBAR + MCFSIM_ICR4);

	for (irq = 0; (irq < NR_IRQS); irq++) {
		irq_set_chip(irq, &intc_irq_chip);
		edge = 0;
		if ((irq >= MCFINT_VECBASE) && (irq <= MCFINT_VECMAX))
			edge = intc_irqmap[irq - MCFINT_VECBASE].ack;
		if (edge) {
			irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
			irq_set_handler(irq, intc_external_irq);
		} else {
			irq_set_irq_type(irq, IRQ_TYPE_LEVEL_HIGH);
			irq_set_handler(irq, handle_level_irq);
		}
	}
}