1 /*
2 * Copyright (C) 1999, 2000, 2004 MIPS Technologies, Inc.
3 * All rights reserved.
4 * Authors: Carsten Langgaard <carstenl@mips.com>
5 * Maciej W. Rozycki <macro@mips.com>
6 *
7 * Copyright (C) 2009 Lemote Inc.
8 * Author: Wu Zhangjin <wuzhangjin@gmail.com>
9 *
10 * This program is free software; you can distribute it and/or modify it
11 * under the terms of the GNU General Public License (Version 2) as
12 * published by the Free Software Foundation.
13 */
14 #include <linux/types.h>
15 #include <linux/pci.h>
16 #include <linux/kernel.h>
17 #include <linux/export.h>
18
19 #include <loongson.h>
20
21 #ifdef CONFIG_CS5536
22 #include <cs5536/cs5536_pci.h>
23 #include <cs5536/cs5536.h>
24 #endif
25
26 #define PCI_ACCESS_READ 0
27 #define PCI_ACCESS_WRITE 1
28
29 #define CFG_SPACE_REG(offset) \
30 (void *)CKSEG1ADDR(LOONGSON_PCICFG_BASE | (offset))
31 #define ID_SEL_BEGIN 11
32 #define MAX_DEV_NUM (31 - ID_SEL_BEGIN)
33
34
loongson_pcibios_config_access(unsigned char access_type,struct pci_bus * bus,unsigned int devfn,int where,u32 * data)35 static int loongson_pcibios_config_access(unsigned char access_type,
36 struct pci_bus *bus,
37 unsigned int devfn, int where,
38 u32 *data)
39 {
40 u32 busnum = bus->number;
41 u32 addr, type;
42 u32 dummy;
43 void *addrp;
44 int device = PCI_SLOT(devfn);
45 int function = PCI_FUNC(devfn);
46 int reg = where & ~3;
47
48 if (busnum == 0) {
49 /* board-specific part,currently,only fuloong2f,yeeloong2f
50 * use CS5536, fuloong2e use via686b, gdium has no
51 * south bridge
52 */
53 #ifdef CONFIG_CS5536
54 /* cs5536_pci_conf_read4/write4() will call _rdmsr/_wrmsr() to
55 * access the regsters PCI_MSR_ADDR, PCI_MSR_DATA_LO,
56 * PCI_MSR_DATA_HI, which is bigger than PCI_MSR_CTRL, so, it
57 * will not go this branch, but the others. so, no calling dead
58 * loop here.
59 */
60 if ((PCI_IDSEL_CS5536 == device) && (reg < PCI_MSR_CTRL)) {
61 switch (access_type) {
62 case PCI_ACCESS_READ:
63 *data = cs5536_pci_conf_read4(function, reg);
64 break;
65 case PCI_ACCESS_WRITE:
66 cs5536_pci_conf_write4(function, reg, *data);
67 break;
68 }
69 return 0;
70 }
71 #endif
72 /* Type 0 configuration for onboard PCI bus */
73 if (device > MAX_DEV_NUM)
74 return -1;
75
76 addr = (1 << (device + ID_SEL_BEGIN)) | (function << 8) | reg;
77 type = 0;
78 } else {
79 /* Type 1 configuration for offboard PCI bus */
80 addr = (busnum << 16) | (device << 11) | (function << 8) | reg;
81 type = 0x10000;
82 }
83
84 /* Clear aborts */
85 LOONGSON_PCICMD |= LOONGSON_PCICMD_MABORT_CLR | \
86 LOONGSON_PCICMD_MTABORT_CLR;
87
88 LOONGSON_PCIMAP_CFG = (addr >> 16) | type;
89
90 /* Flush Bonito register block */
91 dummy = LOONGSON_PCIMAP_CFG;
92 mmiowb();
93
94 addrp = CFG_SPACE_REG(addr & 0xffff);
95 if (access_type == PCI_ACCESS_WRITE)
96 writel(cpu_to_le32(*data), addrp);
97 else
98 *data = le32_to_cpu(readl(addrp));
99
100 /* Detect Master/Target abort */
101 if (LOONGSON_PCICMD & (LOONGSON_PCICMD_MABORT_CLR |
102 LOONGSON_PCICMD_MTABORT_CLR)) {
103 /* Error occurred */
104
105 /* Clear bits */
106 LOONGSON_PCICMD |= (LOONGSON_PCICMD_MABORT_CLR |
107 LOONGSON_PCICMD_MTABORT_CLR);
108
109 return -1;
110 }
111
112 return 0;
113
114 }
115
116
117 /*
118 * We can't address 8 and 16 bit words directly. Instead we have to
119 * read/write a 32bit word and mask/modify the data we actually want.
120 */
loongson_pcibios_read(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * val)121 static int loongson_pcibios_read(struct pci_bus *bus, unsigned int devfn,
122 int where, int size, u32 *val)
123 {
124 u32 data = 0;
125
126 if ((size == 2) && (where & 1))
127 return PCIBIOS_BAD_REGISTER_NUMBER;
128 else if ((size == 4) && (where & 3))
129 return PCIBIOS_BAD_REGISTER_NUMBER;
130
131 if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
132 &data))
133 return -1;
134
135 if (size == 1)
136 *val = (data >> ((where & 3) << 3)) & 0xff;
137 else if (size == 2)
138 *val = (data >> ((where & 3) << 3)) & 0xffff;
139 else
140 *val = data;
141
142 return PCIBIOS_SUCCESSFUL;
143 }
144
loongson_pcibios_write(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 val)145 static int loongson_pcibios_write(struct pci_bus *bus, unsigned int devfn,
146 int where, int size, u32 val)
147 {
148 u32 data = 0;
149
150 if ((size == 2) && (where & 1))
151 return PCIBIOS_BAD_REGISTER_NUMBER;
152 else if ((size == 4) && (where & 3))
153 return PCIBIOS_BAD_REGISTER_NUMBER;
154
155 if (size == 4)
156 data = val;
157 else {
158 if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
159 where, &data))
160 return -1;
161
162 if (size == 1)
163 data = (data & ~(0xff << ((where & 3) << 3))) |
164 (val << ((where & 3) << 3));
165 else if (size == 2)
166 data = (data & ~(0xffff << ((where & 3) << 3))) |
167 (val << ((where & 3) << 3));
168 }
169
170 if (loongson_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn, where,
171 &data))
172 return -1;
173
174 return PCIBIOS_SUCCESSFUL;
175 }
176
177 struct pci_ops loongson_pci_ops = {
178 .read = loongson_pcibios_read,
179 .write = loongson_pcibios_write
180 };
181
182 #ifdef CONFIG_CS5536
183 DEFINE_RAW_SPINLOCK(msr_lock);
184
_rdmsr(u32 msr,u32 * hi,u32 * lo)185 void _rdmsr(u32 msr, u32 *hi, u32 *lo)
186 {
187 struct pci_bus bus = {
188 .number = PCI_BUS_CS5536
189 };
190 u32 devfn = PCI_DEVFN(PCI_IDSEL_CS5536, 0);
191 unsigned long flags;
192
193 raw_spin_lock_irqsave(&msr_lock, flags);
194 loongson_pcibios_write(&bus, devfn, PCI_MSR_ADDR, 4, msr);
195 loongson_pcibios_read(&bus, devfn, PCI_MSR_DATA_LO, 4, lo);
196 loongson_pcibios_read(&bus, devfn, PCI_MSR_DATA_HI, 4, hi);
197 raw_spin_unlock_irqrestore(&msr_lock, flags);
198 }
199 EXPORT_SYMBOL(_rdmsr);
200
_wrmsr(u32 msr,u32 hi,u32 lo)201 void _wrmsr(u32 msr, u32 hi, u32 lo)
202 {
203 struct pci_bus bus = {
204 .number = PCI_BUS_CS5536
205 };
206 u32 devfn = PCI_DEVFN(PCI_IDSEL_CS5536, 0);
207 unsigned long flags;
208
209 raw_spin_lock_irqsave(&msr_lock, flags);
210 loongson_pcibios_write(&bus, devfn, PCI_MSR_ADDR, 4, msr);
211 loongson_pcibios_write(&bus, devfn, PCI_MSR_DATA_LO, 4, lo);
212 loongson_pcibios_write(&bus, devfn, PCI_MSR_DATA_HI, 4, hi);
213 raw_spin_unlock_irqrestore(&msr_lock, flags);
214 }
215 EXPORT_SYMBOL(_wrmsr);
216 #endif
217
