aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/pci/ops-ddb5477.c
blob: 0406b50a37d8d46c4f72219feed294fd97f7dea4 (plain) (blame)
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
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
/***********************************************************************
 * Copyright 2001 MontaVista Software Inc.
 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
 *
 * arch/mips/ddb5xxx/ddb5477/pci_ops.c
 *     Define the pci_ops for DB5477.
 *
 * Much of the code is derived from the original DDB5074 port by
 * Geert Uytterhoeven <geert@sonycom.com>
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 ***********************************************************************
 */

/*
 * DDB5477 has two PCI channels, external PCI and IOPIC (internal)
 * Therefore we provide two sets of pci_ops.
 */
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/types.h>

#include <asm/addrspace.h>
#include <asm/debug.h>

#include <asm/ddb5xxx/ddb5xxx.h>

/*
 * config_swap structure records what set of pdar/pmr are used
 * to access pci config space.  It also provides a place hold the
 * original values for future restoring.
 */
struct pci_config_swap {
	u32 pdar;
	u32 pmr;
	u32 config_base;
	u32 config_size;
	u32 pdar_backup;
	u32 pmr_backup;
};

/*
 * On DDB5477, we have two sets of swap registers, for ext PCI and IOPCI.
 */
struct pci_config_swap ext_pci_swap = {
	DDB_PCIW0,
	DDB_PCIINIT00,
	DDB_PCI0_CONFIG_BASE,
	DDB_PCI0_CONFIG_SIZE
};
struct pci_config_swap io_pci_swap = {
	DDB_IOPCIW0,
	DDB_PCIINIT01,
	DDB_PCI1_CONFIG_BASE,
	DDB_PCI1_CONFIG_SIZE
};


/*
 * access config space
 */
static inline u32 ddb_access_config_base(struct pci_config_swap *swap, u32 bus,	/* 0 means top level bus */
					 u32 slot_num)
{
	u32 pci_addr = 0;
	u32 pciinit_offset = 0;
	u32 virt_addr;
	u32 option;

	/* minimum pdar (window) size is 2MB */
	db_assert(swap->config_size >= (2 << 20));

	db_assert(slot_num < (1 << 5));
	db_assert(bus < (1 << 8));

	/* backup registers */
	swap->pdar_backup = ddb_in32(swap->pdar);
	swap->pmr_backup = ddb_in32(swap->pmr);

	/* set the pdar (pci window) register */
	ddb_set_pdar(swap->pdar, swap->config_base, swap->config_size, 32,	/* 32 bit wide */
		     0,		/* not on local memory bus */
		     0);	/* not visible from PCI bus (N/A) */

	/*
	 * calcuate the absolute pci config addr;
	 * according to the spec, we start scanning from adr:11 (0x800)
	 */
	if (bus == 0) {
		/* type 0 config */
		pci_addr = 0x800 << slot_num;
	} else {
		/* type 1 config */
		pci_addr = (bus << 16) | (slot_num << 11);
	}

	/*
	 * if pci_addr is less than pci config window size,  we set
	 * pciinit_offset to 0 and adjust the virt_address.
	 * Otherwise we will try to adjust pciinit_offset.
	 */
	if (pci_addr < swap->config_size) {
		virt_addr = KSEG1ADDR(swap->config_base + pci_addr);
		pciinit_offset = 0;
	} else {
		db_assert((pci_addr & (swap->config_size - 1)) == 0);
		virt_addr = KSEG1ADDR(swap->config_base);
		pciinit_offset = pci_addr;
	}

	/* set the pmr register */
	option = DDB_PCI_ACCESS_32;
	if (bus != 0)
		option |= DDB_PCI_CFGTYPE1;
	ddb_set_pmr(swap->pmr, DDB_PCICMD_CFG, pciinit_offset, option);

	return virt_addr;
}

static inline void ddb_close_config_base(struct pci_config_swap *swap)
{
	ddb_out32(swap->pdar, swap->pdar_backup);
	ddb_out32(swap->pmr, swap->pmr_backup);
}

static int read_config_dword(struct pci_config_swap *swap,
			     struct pci_bus *bus, u32 devfn, u32 where,
			     u32 * val)
{
	u32 bus_num, slot_num, func_num;
	u32 base;

	db_assert((where & 3) == 0);
	db_assert(where < (1 << 8));

	/* check if the bus is top-level */
	if (bus->parent != NULL) {
		bus_num = bus->number;
		db_assert(bus_num != 0);
	} else {
		bus_num = 0;
	}

	slot_num = PCI_SLOT(devfn);
	func_num = PCI_FUNC(devfn);
	base = ddb_access_config_base(swap, bus_num, slot_num);
	*val = *(volatile u32 *) (base + (func_num << 8) + where);
	ddb_close_config_base(swap);
	return PCIBIOS_SUCCESSFUL;
}

static int read_config_word(struct pci_config_swap *swap,
			    struct pci_bus *bus, u32 devfn, u32 where,
			    u16 * val)
{
	int status;
	u32 result;

	db_assert((where & 1) == 0);

	status = read_config_dword(swap, bus, devfn, where & ~3, &result);
	if (where & 2)
		result >>= 16;
	*val = result & 0xffff;
	return status;
}

static int read_config_byte(struct pci_config_swap *swap,
			    struct pci_bus *bus, u32 devfn, u32 where,
			    u8 * val)
{
	int status;
	u32 result;

	status = read_config_dword(swap, bus, devfn, where & ~3, &result);
	if (where & 1)
		result >>= 8;
	if (where & 2)
		result >>= 16;
	*val = result & 0xff;

	return status;
}

static int write_config_dword(struct pci_config_swap *swap,
			      struct pci_bus *bus, u32 devfn, u32 where,
			      u32 val)
{
	u32 bus_num, slot_num, func_num;
	u32 base;

	db_assert((where & 3) == 0);
	db_assert(where < (1 << 8));

	/* check if the bus is top-level */
	if (bus->parent != NULL) {
		bus_num = bus->number;
		db_assert(bus_num != 0);
	} else {
		bus_num = 0;
	}

	slot_num = PCI_SLOT(devfn);
	func_num = PCI_FUNC(devfn);
	base = ddb_access_config_base(swap, bus_num, slot_num);
	*(volatile u32 *) (base + (func_num << 8) + where) = val;
	ddb_close_config_base(swap);
	return PCIBIOS_SUCCESSFUL;
}

static int write_config_word(struct pci_config_swap *swap,
			     struct pci_bus *bus, u32 devfn, u32 where, u16 val)
{
	int status, shift = 0;
	u32 result;

	db_assert((where & 1) == 0);

	status = read_config_dword(swap, bus, devfn, where & ~3, &result);
	if (status != PCIBIOS_SUCCESSFUL)
		return status;

	if (where & 2)
		shift += 16;
	result &= ~(0xffff << shift);
	result |= val << shift;
	return write_config_dword(swap, bus, devfn, where & ~3, result);
}

static int write_config_byte(struct pci_config_swap *swap,
			     struct pci_bus *bus, u32 devfn, u32 where, u8 val)
{
	int status, shift = 0;
	u32 result;

	status = read_config_dword(swap, bus, devfn, where & ~3, &result);
	if (status != PCIBIOS_SUCCESSFUL)
		return status;

	if (where & 2)
		shift += 16;
	if (where & 1)
		shift += 8;
	result &= ~(0xff << shift);
	result |= val << shift;
	return write_config_dword(swap, bus, devfn, where & ~3, result);
}

#define        MAKE_PCI_OPS(prefix, rw, pciswap, star) \
static int prefix##_##rw##_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 star val) \
{ \
	if (size == 1) \
     		return rw##_config_byte(pciswap, bus, devfn, where, (u8 star)val); \
	else if (size == 2) \
     		return rw##_config_word(pciswap, bus, devfn, where, (u16 star)val); \
	/* Size must be 4 */ \
     	return rw##_config_dword(pciswap, bus, devfn, where, val); \
}

MAKE_PCI_OPS(extpci, read, &ext_pci_swap, *)
MAKE_PCI_OPS(extpci, write, &ext_pci_swap,)

MAKE_PCI_OPS(iopci, read, &io_pci_swap, *)
MAKE_PCI_OPS(iopci, write, &io_pci_swap,)

struct pci_ops ddb5477_ext_pci_ops = {
	.read = extpci_read_config,
	.write = extpci_write_config
};


struct pci_ops ddb5477_io_pci_ops = {
	.read = iopci_read_config,
	.write = iopci_write_config
};