summaryrefslogtreecommitdiff
path: root/arch/arm/mach-iop13xx/msi.c
blob: 2d2369302220b0ebbacf6eee86890ec0400a3cbd (plain)
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
188
189
190
191
192
193
194
/*
 * arch/arm/mach-iop13xx/msi.c
 *
 * PCI MSI support for the iop13xx processor
 *
 * Copyright (c) 2006, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place - Suite 330, Boston, MA 02111-1307 USA.
 *
 */
#include <linux/pci.h>
#include <linux/msi.h>
#include <asm/mach/irq.h>
#include <asm/irq.h>


#define IOP13XX_NUM_MSI_IRQS 128
static DECLARE_BITMAP(msi_irq_in_use, IOP13XX_NUM_MSI_IRQS);

/* IMIPR0 CP6 R8 Page 1
 */
static inline u32 read_imipr_0(void)
{
	u32 val;
	asm volatile("mrc p6, 0, %0, c8, c1, 0":"=r" (val));
	return val;
}
static inline void write_imipr_0(u32 val)
{
	asm volatile("mcr p6, 0, %0, c8, c1, 0"::"r" (val));
}

/* IMIPR1 CP6 R9 Page 1
 */
static inline u32 read_imipr_1(void)
{
	u32 val;
	asm volatile("mrc p6, 0, %0, c9, c1, 0":"=r" (val));
	return val;
}
static inline void write_imipr_1(u32 val)
{
	asm volatile("mcr p6, 0, %0, c9, c1, 0"::"r" (val));
}

/* IMIPR2 CP6 R10 Page 1
 */
static inline u32 read_imipr_2(void)
{
	u32 val;
	asm volatile("mrc p6, 0, %0, c10, c1, 0":"=r" (val));
	return val;
}
static inline void write_imipr_2(u32 val)
{
	asm volatile("mcr p6, 0, %0, c10, c1, 0"::"r" (val));
}

/* IMIPR3 CP6 R11 Page 1
 */
static inline u32 read_imipr_3(void)
{
	u32 val;
	asm volatile("mrc p6, 0, %0, c11, c1, 0":"=r" (val));
	return val;
}
static inline void write_imipr_3(u32 val)
{
	asm volatile("mcr p6, 0, %0, c11, c1, 0"::"r" (val));
}

static u32 (*read_imipr[])(void) = {
	read_imipr_0,
	read_imipr_1,
	read_imipr_2,
	read_imipr_3,
};

static void (*write_imipr[])(u32) = {
	write_imipr_0,
	write_imipr_1,
	write_imipr_2,
	write_imipr_3,
};

static void iop13xx_msi_handler(unsigned int irq, struct irq_desc *desc)
{
	int i, j;
	unsigned long status;

	/* read IMIPR registers and find any active interrupts,
	 * then call ISR for each active interrupt
	 */
	for (i = 0; i < ARRAY_SIZE(read_imipr); i++) {
		status = (read_imipr[i])();
		if (!status)
			continue;

		do {
			j = find_first_bit(&status, 32);
			(write_imipr[i])(1 << j); /* write back to clear bit */
			desc = irq_desc + IRQ_IOP13XX_MSI_0 + j + (32*i);
			desc_handle_irq(IRQ_IOP13XX_MSI_0 + j + (32*i),	desc);
			status = (read_imipr[i])();
		} while (status);
	}
}

void __init iop13xx_msi_init(void)
{
	set_irq_chained_handler(IRQ_IOP13XX_INBD_MSI, iop13xx_msi_handler);
}

/*
 * Dynamic irq allocate and deallocation
 */
int create_irq(void)
{
	int irq, pos;

again:
	pos = find_first_zero_bit(msi_irq_in_use, IOP13XX_NUM_MSI_IRQS);
	irq = IRQ_IOP13XX_MSI_0 + pos;
	if (irq > NR_IRQS)
		return -ENOSPC;
	/* test_and_set_bit operates on 32-bits at a time */
	if (test_and_set_bit(pos, msi_irq_in_use))
		goto again;

	dynamic_irq_init(irq);

	return irq;
}

void destroy_irq(unsigned int irq)
{
	int pos = irq - IRQ_IOP13XX_MSI_0;

	dynamic_irq_cleanup(irq);

	clear_bit(pos, msi_irq_in_use);
}

void arch_teardown_msi_irq(unsigned int irq)
{
	destroy_irq(irq);
}

static void iop13xx_msi_nop(unsigned int irq)
{
	return;
}

static struct irq_chip iop13xx_msi_chip = {
	.name = "PCI-MSI",
	.ack = iop13xx_msi_nop,
	.enable = unmask_msi_irq,
	.disable = mask_msi_irq,
	.mask = mask_msi_irq,
	.unmask = unmask_msi_irq,
};

int arch_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc)
{
	int id, irq = create_irq();
	struct msi_msg msg;

	if (irq < 0)
		return irq;

	set_irq_msi(irq, desc);

	msg.address_hi = 0x0;
	msg.address_lo = IOP13XX_MU_MIMR_PCI;

	id = iop13xx_cpu_id();
	msg.data = (id << IOP13XX_MU_MIMR_CORE_SELECT) | (irq & 0x7f);

	write_msi_msg(irq, &msg);
	set_irq_chip_and_handler(irq, &iop13xx_msi_chip, handle_simple_irq);

	return irq;
}