tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1/*
2 * Copyright 2001 MontaVista Software Inc.
3 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
4 *
5 * arch/mips/ddb5xxx/ddb5476/pci_ops.c
6 * Define the pci_ops for DB5477.
7 *
8 * Much of the code is derived from the original DDB5074 port by
9 * Geert Uytterhoeven <geert@sonycom.com>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
15 *
16 */
17#include <linux/pci.h>
18#include <linux/kernel.h>
19#include <linux/types.h>
20
21#include <asm/addrspace.h>
22#include <asm/debug.h>
23
24#include <asm/ddb5xxx/ddb5xxx.h>
25
26/*
27 * config_swap structure records what set of pdar/pmr are used
28 * to access pci config space. It also provides a place hold the
29 * original values for future restoring.
30 */
31struct pci_config_swap {
32 u32 pdar;
33 u32 pmr;
34 u32 config_base;
35 u32 config_size;
36 u32 pdar_backup;
37 u32 pmr_backup;
38};
39
40/*
41 * On DDB5476, we have one set of swap registers
42 */
43struct pci_config_swap ext_pci_swap = {
44 DDB_PCIW0,
45 DDB_PCIINIT0,
46 DDB_PCI_CONFIG_BASE,
47 DDB_PCI_CONFIG_SIZE
48};
49
50static int pci_config_workaround = 1;
51
52/*
53 * access config space
54 */
55static inline u32 ddb_access_config_base(struct pci_config_swap *swap, u32 bus, /* 0 means top level bus */
56 u32 slot_num)
57{
58 u32 pci_addr = 0;
59 u32 pciinit_offset = 0;
60 u32 virt_addr = swap->config_base;
61 u32 option;
62
63 if (pci_config_workaround) {
64 if (slot_num == 5)
65 slot_num = 14;
66 } else {
67 if (slot_num == 5)
68 return DDB_BASE + DDB_PCI_BASE;
69 }
70
71 /* minimum pdar (window) size is 2MB */
72 db_assert(swap->config_size >= (2 << 20));
73
74 db_assert(slot_num < (1 << 5));
75 db_assert(bus < (1 << 8));
76
77 /* backup registers */
78 swap->pdar_backup = ddb_in32(swap->pdar);
79 swap->pmr_backup = ddb_in32(swap->pmr);
80
81 /* set the pdar (pci window) register */
82 ddb_set_pdar(swap->pdar, swap->config_base, swap->config_size, 32, /* 32 bit wide */
83 0, /* not on local memory bus */
84 0); /* not visible from PCI bus (N/A) */
85
86 /*
87 * calcuate the absolute pci config addr;
88 * according to the spec, we start scanning from adr:11 (0x800)
89 */
90 if (bus == 0) {
91 /* type 0 config */
92 pci_addr = 0x00040000 << slot_num;
93 } else {
94 /* type 1 config */
95 pci_addr = 0x00040000 << slot_num;
96 panic
97 ("ddb_access_config_base: we don't support type 1 config Yet");
98 }
99
100 /*
101 * if pci_addr is less than pci config window size, we set
102 * pciinit_offset to 0 and adjust the virt_address.
103 * Otherwise we will try to adjust pciinit_offset.
104 */
105 if (pci_addr < swap->config_size) {
106 virt_addr = KSEG1ADDR(swap->config_base + pci_addr);
107 pciinit_offset = 0;
108 } else {
109 db_assert((pci_addr & (swap->config_size - 1)) == 0);
110 virt_addr = KSEG1ADDR(swap->config_base);
111 pciinit_offset = pci_addr;
112 }
113
114 /* set the pmr register */
115 option = DDB_PCI_ACCESS_32;
116 if (bus != 0)
117 option |= DDB_PCI_CFGTYPE1;
118 ddb_set_pmr(swap->pmr, DDB_PCICMD_CFG, pciinit_offset, option);
119
120 return virt_addr;
121}
122
123static inline void ddb_close_config_base(struct pci_config_swap *swap)
124{
125 ddb_out32(swap->pdar, swap->pdar_backup);
126 ddb_out32(swap->pmr, swap->pmr_backup);
127}
128
129static int read_config_dword(struct pci_config_swap *swap,
130 struct pci_dev *dev, u32 where, u32 * val)
131{
132 u32 bus, slot_num, func_num;
133 u32 base;
134
135 db_assert((where & 3) == 0);
136 db_assert(where < (1 << 8));
137
138 /* check if the bus is top-level */
139 if (dev->bus->parent != NULL) {
140 bus = dev->bus->number;
141 db_assert(bus != 0);
142 } else {
143 bus = 0;
144 }
145
146 slot_num = PCI_SLOT(dev->devfn);
147 func_num = PCI_FUNC(dev->devfn);
148 base = ddb_access_config_base(swap, bus, slot_num);
149 *val = *(volatile u32 *) (base + (func_num << 8) + where);
150 ddb_close_config_base(swap);
151 return PCIBIOS_SUCCESSFUL;
152}
153
154static int read_config_word(struct pci_config_swap *swap,
155 struct pci_dev *dev, u32 where, u16 * val)
156{
157 int status;
158 u32 result;
159
160 db_assert((where & 1) == 0);
161
162 status = read_config_dword(swap, dev, where & ~3, &result);
163 if (where & 2)
164 result >>= 16;
165 *val = result & 0xffff;
166 return status;
167}
168
169static int read_config_byte(struct pci_config_swap *swap,
170 struct pci_dev *dev, u32 where, u8 * val)
171{
172 int status;
173 u32 result;
174
175 status = read_config_dword(swap, dev, where & ~3, &result);
176 if (where & 1)
177 result >>= 8;
178 if (where & 2)
179 result >>= 16;
180 *val = result & 0xff;
181 return status;
182}
183
184static int write_config_dword(struct pci_config_swap *swap,
185 struct pci_dev *dev, u32 where, u32 val)
186{
187 u32 bus, slot_num, func_num;
188 u32 base;
189
190 db_assert((where & 3) == 0);
191 db_assert(where < (1 << 8));
192
193 /* check if the bus is top-level */
194 if (dev->bus->parent != NULL) {
195 bus = dev->bus->number;
196 db_assert(bus != 0);
197 } else {
198 bus = 0;
199 }
200
201 slot_num = PCI_SLOT(dev->devfn);
202 func_num = PCI_FUNC(dev->devfn);
203 base = ddb_access_config_base(swap, bus, slot_num);
204 *(volatile u32 *) (base + (func_num << 8) + where) = val;
205 ddb_close_config_base(swap);
206 return PCIBIOS_SUCCESSFUL;
207}
208
209static int write_config_word(struct pci_config_swap *swap,
210 struct pci_dev *dev, u32 where, u16 val)
211{
212 int status, shift = 0;
213 u32 result;
214
215 db_assert((where & 1) == 0);
216
217 status = read_config_dword(swap, dev, where & ~3, &result);
218 if (status != PCIBIOS_SUCCESSFUL)
219 return status;
220
221 if (where & 2)
222 shift += 16;
223 result &= ~(0xffff << shift);
224 result |= val << shift;
225 return write_config_dword(swap, dev, where & ~3, result);
226}
227
228static int write_config_byte(struct pci_config_swap *swap,
229 struct pci_dev *dev, u32 where, u8 val)
230{
231 int status, shift = 0;
232 u32 result;
233
234 status = read_config_dword(swap, dev, where & ~3, &result);
235 if (status != PCIBIOS_SUCCESSFUL)
236 return status;
237
238 if (where & 2)
239 shift += 16;
240 if (where & 1)
241 shift += 8;
242 result &= ~(0xff << shift);
243 result |= val << shift;
244 return write_config_dword(swap, dev, where & ~3, result);
245}
246
247#define MAKE_PCI_OPS(prefix, rw, unitname, unittype, pciswap) \
248static int prefix##_##rw##_config_##unitname(struct pci_dev *dev, int where, unittype val) \
249{ \
250 return rw##_config_##unitname(pciswap, \
251 dev, \
252 where, \
253 val); \
254}
255
256MAKE_PCI_OPS(extpci, read, byte, u8 *, &ext_pci_swap)
257 MAKE_PCI_OPS(extpci, read, word, u16 *, &ext_pci_swap)
258 MAKE_PCI_OPS(extpci, read, dword, u32 *, &ext_pci_swap)
259
260 MAKE_PCI_OPS(extpci, write, byte, u8, &ext_pci_swap)
261 MAKE_PCI_OPS(extpci, write, word, u16, &ext_pci_swap)
262 MAKE_PCI_OPS(extpci, write, dword, u32, &ext_pci_swap)
263
264struct pci_ops ddb5476_ext_pci_ops = {
265 extpci_read_config_byte,
266 extpci_read_config_word,
267 extpci_read_config_dword,
268 extpci_write_config_byte,
269 extpci_write_config_word,
270 extpci_write_config_dword
271};