blob: f34b0ed806305474221051fa2b000199330b9e73 [file] [log] [blame]
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -07001/*
2 * arch/arm/mach-iop13xx/msi.c
3 *
4 * PCI MSI support for the iop13xx processor
5 *
6 * Copyright (c) 2006, Intel Corporation.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
19 * Place - Suite 330, Boston, MA 02111-1307 USA.
20 *
21 */
22#include <linux/pci.h>
23#include <linux/msi.h>
24#include <asm/mach/irq.h>
25#include <asm/irq.h>
26
27
28#define IOP13XX_NUM_MSI_IRQS 128
29static DECLARE_BITMAP(msi_irq_in_use, IOP13XX_NUM_MSI_IRQS);
30
31/* IMIPR0 CP6 R8 Page 1
32 */
Dan Williamsd73d8012007-05-15 01:03:36 +010033static u32 read_imipr_0(void)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070034{
35 u32 val;
36 asm volatile("mrc p6, 0, %0, c8, c1, 0":"=r" (val));
37 return val;
38}
Dan Williamsd73d8012007-05-15 01:03:36 +010039static void write_imipr_0(u32 val)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070040{
41 asm volatile("mcr p6, 0, %0, c8, c1, 0"::"r" (val));
42}
43
44/* IMIPR1 CP6 R9 Page 1
45 */
Dan Williamsd73d8012007-05-15 01:03:36 +010046static u32 read_imipr_1(void)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070047{
48 u32 val;
49 asm volatile("mrc p6, 0, %0, c9, c1, 0":"=r" (val));
50 return val;
51}
Dan Williamsd73d8012007-05-15 01:03:36 +010052static void write_imipr_1(u32 val)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070053{
54 asm volatile("mcr p6, 0, %0, c9, c1, 0"::"r" (val));
55}
56
57/* IMIPR2 CP6 R10 Page 1
58 */
Dan Williamsd73d8012007-05-15 01:03:36 +010059static u32 read_imipr_2(void)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070060{
61 u32 val;
62 asm volatile("mrc p6, 0, %0, c10, c1, 0":"=r" (val));
63 return val;
64}
Dan Williamsd73d8012007-05-15 01:03:36 +010065static void write_imipr_2(u32 val)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070066{
67 asm volatile("mcr p6, 0, %0, c10, c1, 0"::"r" (val));
68}
69
70/* IMIPR3 CP6 R11 Page 1
71 */
Dan Williamsd73d8012007-05-15 01:03:36 +010072static u32 read_imipr_3(void)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070073{
74 u32 val;
75 asm volatile("mrc p6, 0, %0, c11, c1, 0":"=r" (val));
76 return val;
77}
Dan Williamsd73d8012007-05-15 01:03:36 +010078static void write_imipr_3(u32 val)
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -070079{
80 asm volatile("mcr p6, 0, %0, c11, c1, 0"::"r" (val));
81}
82
83static u32 (*read_imipr[])(void) = {
84 read_imipr_0,
85 read_imipr_1,
86 read_imipr_2,
87 read_imipr_3,
88};
89
90static void (*write_imipr[])(u32) = {
91 write_imipr_0,
92 write_imipr_1,
93 write_imipr_2,
94 write_imipr_3,
95};
96
97static void iop13xx_msi_handler(unsigned int irq, struct irq_desc *desc)
98{
99 int i, j;
100 unsigned long status;
101
102 /* read IMIPR registers and find any active interrupts,
103 * then call ISR for each active interrupt
104 */
105 for (i = 0; i < ARRAY_SIZE(read_imipr); i++) {
106 status = (read_imipr[i])();
107 if (!status)
108 continue;
109
110 do {
111 j = find_first_bit(&status, 32);
112 (write_imipr[i])(1 << j); /* write back to clear bit */
Dmitry Baryshkovd8aa0252008-10-09 13:36:24 +0100113 generic_handle_irq(IRQ_IOP13XX_MSI_0 + j + (32*i));
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -0700114 status = (read_imipr[i])();
115 } while (status);
116 }
117}
118
119void __init iop13xx_msi_init(void)
120{
121 set_irq_chained_handler(IRQ_IOP13XX_INBD_MSI, iop13xx_msi_handler);
122}
123
124/*
125 * Dynamic irq allocate and deallocation
126 */
127int create_irq(void)
128{
129 int irq, pos;
130
131again:
132 pos = find_first_zero_bit(msi_irq_in_use, IOP13XX_NUM_MSI_IRQS);
133 irq = IRQ_IOP13XX_MSI_0 + pos;
134 if (irq > NR_IRQS)
135 return -ENOSPC;
136 /* test_and_set_bit operates on 32-bits at a time */
137 if (test_and_set_bit(pos, msi_irq_in_use))
138 goto again;
139
140 dynamic_irq_init(irq);
141
142 return irq;
143}
144
145void destroy_irq(unsigned int irq)
146{
147 int pos = irq - IRQ_IOP13XX_MSI_0;
148
149 dynamic_irq_cleanup(irq);
150
151 clear_bit(pos, msi_irq_in_use);
152}
153
154void arch_teardown_msi_irq(unsigned int irq)
155{
156 destroy_irq(irq);
157}
158
159static void iop13xx_msi_nop(unsigned int irq)
160{
161 return;
162}
163
164static struct irq_chip iop13xx_msi_chip = {
165 .name = "PCI-MSI",
166 .ack = iop13xx_msi_nop,
167 .enable = unmask_msi_irq,
168 .disable = mask_msi_irq,
169 .mask = mask_msi_irq,
170 .unmask = unmask_msi_irq,
171};
172
173int arch_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc)
174{
175 int id, irq = create_irq();
176 struct msi_msg msg;
177
178 if (irq < 0)
179 return irq;
180
181 set_irq_msi(irq, desc);
182
183 msg.address_hi = 0x0;
184 msg.address_lo = IOP13XX_MU_MIMR_PCI;
185
186 id = iop13xx_cpu_id();
187 msg.data = (id << IOP13XX_MU_MIMR_CORE_SELECT) | (irq & 0x7f);
188
189 write_msi_msg(irq, &msg);
190 set_irq_chip_and_handler(irq, &iop13xx_msi_chip, handle_simple_irq);
191
Dan Williamse702a712007-05-15 01:03:31 +0100192 return 0;
Daniel Wolstenholme2fd02372007-05-10 22:33:02 -0700193}