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gerrit-public.fairphone.software / kernel / msm / e2fee5723bbda4a05c86f16a9d0f889a2c4ecede / . / arch / mips / pci / ops-fuloong2e.c
blob: 171f65c99ca15e993806df953506b6b6b839f2e3 [file] [log] [blame]
Wu Zhangjine2fee572009-10-16 14:17:19 +0800[diff] [blame^]1/*
2 * fuloong2e specific PCI support.
3 *
4 * Copyright (C) 1999, 2000, 2004 MIPS Technologies, Inc.
5 * All rights reserved.
6 * Authors: Carsten Langgaard <carstenl@mips.com>
7 * Maciej W. Rozycki <macro@mips.com>
8 *
9 * Copyright (C) 2009 Lemote Inc.
10 * Author: Wu Zhangjin <wuzj@lemote.com>
11 *
12 * This program is free software; you can distribute it and/or modify it
13 * under the terms of the GNU General Public License (Version 2) as
14 * published by the Free Software Foundation.
15 */
16#include <linux/types.h>
17#include <linux/pci.h>
18#include <linux/kernel.h>
19#include <linux/init.h>
20
21#include <loongson.h>
22
23#define PCI_ACCESS_READ 0
24#define PCI_ACCESS_WRITE 1
25
26#define CFG_SPACE_REG(offset) \
27 (void *)CKSEG1ADDR(LOONGSON_PCICFG_BASE | (offset))
28#define ID_SEL_BEGIN 11
29#define MAX_DEV_NUM (31 - ID_SEL_BEGIN)
30
31
32static int loongson_pcibios_config_access(unsigned char access_type,
33 struct pci_bus *bus,
34 unsigned int devfn, int where,
35 u32 *data)
36{
37 u32 busnum = bus->number;
38 u32 addr, type;
39 u32 dummy;
40 void *addrp;
41 int device = PCI_SLOT(devfn);
42 int function = PCI_FUNC(devfn);
43 int reg = where & ~3;
44
45 if (busnum == 0) {
46 /* Type 0 configuration for onboard PCI bus */
47 if (device > MAX_DEV_NUM)
48 return -1;
49
50 addr = (1 << (device + ID_SEL_BEGIN)) | (function << 8) | reg;
51 type = 0;
52 } else {
53 /* Type 1 configuration for offboard PCI bus */
54 addr = (busnum << 16) | (device << 11) | (function << 8) | reg;
55 type = 0x10000;
56 }
57
58 /* Clear aborts */
59 LOONGSON_PCICMD |= LOONGSON_PCICMD_MABORT_CLR | \
60 LOONGSON_PCICMD_MTABORT_CLR;
61
62 LOONGSON_PCIMAP_CFG = (addr >> 16) | type;
63
64 /* Flush Bonito register block */
65 dummy = LOONGSON_PCIMAP_CFG;
66 mmiowb();
67
68 addrp = CFG_SPACE_REG(addr & 0xffff);
69 if (access_type == PCI_ACCESS_WRITE)
70 writel(cpu_to_le32(*data), addrp);
71 else
72 *data = le32_to_cpu(readl(addrp));
73
74 /* Detect Master/Target abort */
75 if (LOONGSON_PCICMD & (LOONGSON_PCICMD_MABORT_CLR |
76 LOONGSON_PCICMD_MTABORT_CLR)) {
77 /* Error occurred */
78
79 /* Clear bits */
80 LOONGSON_PCICMD |= (LOONGSON_PCICMD_MABORT_CLR |
81 LOONGSON_PCICMD_MTABORT_CLR);
82
83 return -1;
84 }
85
86 return 0;
87
88}
89
90
91/*
92 * We can't address 8 and 16 bit words directly. Instead we have to
93 * read/write a 32bit word and mask/modify the data we actually want.
94 */
95static int loongson_pcibios_read(struct pci_bus *bus, unsigned int devfn,
96 int where, int size, u32 *val)
97{
98 u32 data = 0;
99
100 if ((size == 2) && (where & 1))
101 return PCIBIOS_BAD_REGISTER_NUMBER;
102 else if ((size == 4) && (where & 3))
103 return PCIBIOS_BAD_REGISTER_NUMBER;
104
105 if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
106 &data))
107 return -1;
108
109 if (size == 1)
110 *val = (data >> ((where & 3) << 3)) & 0xff;
111 else if (size == 2)
112 *val = (data >> ((where & 3) << 3)) & 0xffff;
113 else
114 *val = data;
115
116 return PCIBIOS_SUCCESSFUL;
117}
118
119static int loongson_pcibios_write(struct pci_bus *bus, unsigned int devfn,
120 int where, int size, u32 val)
121{
122 u32 data = 0;
123
124 if ((size == 2) && (where & 1))
125 return PCIBIOS_BAD_REGISTER_NUMBER;
126 else if ((size == 4) && (where & 3))
127 return PCIBIOS_BAD_REGISTER_NUMBER;
128
129 if (size == 4)
130 data = val;
131 else {
132 if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
133 where, &data))
134 return -1;
135
136 if (size == 1)
137 data = (data & ~(0xff << ((where & 3) << 3))) |
138 (val << ((where & 3) << 3));
139 else if (size == 2)
140 data = (data & ~(0xffff << ((where & 3) << 3))) |
141 (val << ((where & 3) << 3));
142 }
143
144 if (loongson_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn, where,
145 &data))
146 return -1;
147
148 return PCIBIOS_SUCCESSFUL;
149}
150
151struct pci_ops loongson_pci_ops = {
152 .read = loongson_pcibios_read,
153 .write = loongson_pcibios_write
154};