summaryrefslogtreecommitdiffstats
path: root/arch/mips/pci/ops-loongson2.c
blob: afd221122d222722d355c6723547ae3657853c5f (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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/*
 * Copyright (C) 1999, 2000, 2004  MIPS Technologies, Inc.
 *	All rights reserved.
 *	Authors: Carsten Langgaard <carstenl@mips.com>
 *		 Maciej W. Rozycki <macro@mips.com>
 *
 * Copyright (C) 2009 Lemote Inc.
 * Author: Wu Zhangjin <wuzhangjin@gmail.com>
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 */
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/export.h>

#include <loongson.h>

#ifdef CONFIG_CS5536
#include <cs5536/cs5536_pci.h>
#include <cs5536/cs5536.h>
#endif

#define PCI_ACCESS_READ  0
#define PCI_ACCESS_WRITE 1

#define CFG_SPACE_REG(offset) \
	(void *)CKSEG1ADDR(LOONGSON_PCICFG_BASE | (offset))
#define ID_SEL_BEGIN 11
#define MAX_DEV_NUM (31 - ID_SEL_BEGIN)


static int loongson_pcibios_config_access(unsigned char access_type,
				      struct pci_bus *bus,
				      unsigned int devfn, int where,
				      u32 *data)
{
	u32 busnum = bus->number;
	u32 addr, type;
	u32 dummy;
	void *addrp;
	int device = PCI_SLOT(devfn);
	int function = PCI_FUNC(devfn);
	int reg = where & ~3;

	if (busnum == 0) {
		/* board-specific part,currently,only fuloong2f,yeeloong2f
		 * use CS5536, fuloong2e use via686b, gdium has no
		 * south bridge
		 */
#ifdef CONFIG_CS5536
		/* cs5536_pci_conf_read4/write4() will call _rdmsr/_wrmsr() to
		 * access the regsters PCI_MSR_ADDR, PCI_MSR_DATA_LO,
		 * PCI_MSR_DATA_HI, which is bigger than PCI_MSR_CTRL, so, it
		 * will not go this branch, but the others. so, no calling dead
		 * loop here.
		 */
		if ((PCI_IDSEL_CS5536 == device) && (reg < PCI_MSR_CTRL)) {
			switch (access_type) {
			case PCI_ACCESS_READ:
				*data = cs5536_pci_conf_read4(function, reg);
				break;
			case PCI_ACCESS_WRITE:
				cs5536_pci_conf_write4(function, reg, *data);
				break;
			}
			return 0;
		}
#endif
		/* Type 0 configuration for onboard PCI bus */
		if (device > MAX_DEV_NUM)
			return -1;

		addr = (1 << (device + ID_SEL_BEGIN)) | (function << 8) | reg;
		type = 0;
	} else {
		/* Type 1 configuration for offboard PCI bus */
		addr = (busnum << 16) | (device << 11) | (function << 8) | reg;
		type = 0x10000;
	}

	/* Clear aborts */
	LOONGSON_PCICMD |= LOONGSON_PCICMD_MABORT_CLR | \
				LOONGSON_PCICMD_MTABORT_CLR;

	LOONGSON_PCIMAP_CFG = (addr >> 16) | type;

	/* Flush Bonito register block */
	dummy = LOONGSON_PCIMAP_CFG;
	mmiowb();

	addrp = CFG_SPACE_REG(addr & 0xffff);
	if (access_type == PCI_ACCESS_WRITE)
		writel(cpu_to_le32(*data), addrp);
	else
		*data = le32_to_cpu(readl(addrp));

	/* Detect Master/Target abort */
	if (LOONGSON_PCICMD & (LOONGSON_PCICMD_MABORT_CLR |
			     LOONGSON_PCICMD_MTABORT_CLR)) {
		/* Error occurred */

		/* Clear bits */
		LOONGSON_PCICMD |= (LOONGSON_PCICMD_MABORT_CLR |
				  LOONGSON_PCICMD_MTABORT_CLR);

		return -1;
	}

	return 0;

}


/*
 * We can't address 8 and 16 bit words directly.  Instead we have to
 * read/write a 32bit word and mask/modify the data we actually want.
 */
static int loongson_pcibios_read(struct pci_bus *bus, unsigned int devfn,
			     int where, int size, u32 *val)
{
	u32 data = 0;

	if ((size == 2) && (where & 1))
		return PCIBIOS_BAD_REGISTER_NUMBER;
	else if ((size == 4) && (where & 3))
		return PCIBIOS_BAD_REGISTER_NUMBER;

	if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
				       &data))
		return -1;

	if (size == 1)
		*val = (data >> ((where & 3) << 3)) & 0xff;
	else if (size == 2)
		*val = (data >> ((where & 3) << 3)) & 0xffff;
	else
		*val = data;

	return PCIBIOS_SUCCESSFUL;
}

static int loongson_pcibios_write(struct pci_bus *bus, unsigned int devfn,
			      int where, int size, u32 val)
{
	u32 data = 0;

	if ((size == 2) && (where & 1))
		return PCIBIOS_BAD_REGISTER_NUMBER;
	else if ((size == 4) && (where & 3))
		return PCIBIOS_BAD_REGISTER_NUMBER;

	if (size == 4)
		data = val;
	else {
		if (loongson_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
					where, &data))
			return -1;

		if (size == 1)
			data = (data & ~(0xff << ((where & 3) << 3))) |
				(val << ((where & 3) << 3));
		else if (size == 2)
			data = (data & ~(0xffff << ((where & 3) << 3))) |
				(val << ((where & 3) << 3));
	}

	if (loongson_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn, where,
				       &data))
		return -1;

	return PCIBIOS_SUCCESSFUL;
}

struct pci_ops loongson_pci_ops = {
	.read = loongson_pcibios_read,
	.write = loongson_pcibios_write
};

#ifdef CONFIG_CS5536
DEFINE_RAW_SPINLOCK(msr_lock);

void _rdmsr(u32 msr, u32 *hi, u32 *lo)
{
	struct pci_bus bus = {
		.number = PCI_BUS_CS5536
	};
	u32 devfn = PCI_DEVFN(PCI_IDSEL_CS5536, 0);
	unsigned long flags;

	raw_spin_lock_irqsave(&msr_lock, flags);
	loongson_pcibios_write(&bus, devfn, PCI_MSR_ADDR, 4, msr);
	loongson_pcibios_read(&bus, devfn, PCI_MSR_DATA_LO, 4, lo);
	loongson_pcibios_read(&bus, devfn, PCI_MSR_DATA_HI, 4, hi);
	raw_spin_unlock_irqrestore(&msr_lock, flags);
}
EXPORT_SYMBOL(_rdmsr);

void _wrmsr(u32 msr, u32 hi, u32 lo)
{
	struct pci_bus bus = {
		.number = PCI_BUS_CS5536
	};
	u32 devfn = PCI_DEVFN(PCI_IDSEL_CS5536, 0);
	unsigned long flags;

	raw_spin_lock_irqsave(&msr_lock, flags);
	loongson_pcibios_write(&bus, devfn, PCI_MSR_ADDR, 4, msr);
	loongson_pcibios_write(&bus, devfn, PCI_MSR_DATA_LO, 4, lo);
	loongson_pcibios_write(&bus, devfn, PCI_MSR_DATA_HI, 4, hi);
	raw_spin_unlock_irqrestore(&msr_lock, flags);
}
EXPORT_SYMBOL(_wrmsr);
#endif
OpenPOWER on IntegriCloud