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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* arch/xtensa/kernel/pci.c
*
* PCI bios-type initialisation for PCI machines
*
* Copyright (C) 2001-2005 Tensilica Inc.
*
* Based largely on work from Cort (ppc/kernel/pci.c)
* IO functions copied from sparc.
*
* Chris Zankel <chris@zankel.net>
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/memblock.h>
#include <asm/pci-bridge.h>
#include <asm/platform.h>
/* PCI Controller */
/*
* pcibios_alloc_controller
* pcibios_enable_device
* pcibios_fixups
* pcibios_align_resource
* pcibios_fixup_bus
* pci_bus_add_device
*/
static struct pci_controller *pci_ctrl_head;
static struct pci_controller **pci_ctrl_tail = &pci_ctrl_head;
static int pci_bus_count;
/*
* We need to avoid collisions with `mirrored' VGA ports
* and other strange ISA hardware, so we always want the
* addresses to be allocated in the 0x000-0x0ff region
* modulo 0x400.
*
* Why? Because some silly external IO cards only decode
* the low 10 bits of the IO address. The 0x00-0xff region
* is reserved for motherboard devices that decode all 16
* bits, so it's ok to allocate at, say, 0x2800-0x28ff,
* but we want to try to avoid allocating at 0x2900-0x2bff
* which might have be mirrored at 0x0100-0x03ff..
*/
resource_size_t
pcibios_align_resource(void *data, const struct resource *res,
resource_size_t size, resource_size_t align)
{
struct pci_dev *dev = data;
resource_size_t start = res->start;
if (res->flags & IORESOURCE_IO) {
if (size > 0x100) {
pr_err("PCI: I/O Region %s/%d too large (%u bytes)\n",
pci_name(dev), dev->resource - res,
size);
}
if (start & 0x300)
start = (start + 0x3ff) & ~0x3ff;
}
return start;
}
static void __init pci_controller_apertures(struct pci_controller *pci_ctrl,
struct list_head *resources)
{
struct resource *res;
unsigned long io_offset;
int i;
io_offset = (unsigned long)pci_ctrl->io_space.base;
res = &pci_ctrl->io_resource;
if (!res->flags) {
if (io_offset)
pr_err("I/O resource not set for host bridge %d\n",
pci_ctrl->index);
res->start = 0;
res->end = IO_SPACE_LIMIT;
res->flags = IORESOURCE_IO;
}
res->start += io_offset;
res->end += io_offset;
pci_add_resource_offset(resources, res, io_offset);
for (i = 0; i < 3; i++) {
res = &pci_ctrl->mem_resources[i];
if (!res->flags) {
if (i > 0)
continue;
pr_err("Memory resource not set for host bridge %d\n",
pci_ctrl->index);
res->start = 0;
res->end = ~0U;
res->flags = IORESOURCE_MEM;
}
pci_add_resource(resources, res);
}
}
static int __init pcibios_init(void)
{
struct pci_controller *pci_ctrl;
struct list_head resources;
struct pci_bus *bus;
int next_busno = 0, ret;
pr_info("PCI: Probing PCI hardware\n");
/* Scan all of the recorded PCI controllers. */
for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) {
pci_ctrl->last_busno = 0xff;
INIT_LIST_HEAD(&resources);
pci_controller_apertures(pci_ctrl, &resources);
bus = pci_scan_root_bus(NULL, pci_ctrl->first_busno,
pci_ctrl->ops, pci_ctrl, &resources);
if (!bus)
continue;
pci_ctrl->bus = bus;
pci_ctrl->last_busno = bus->busn_res.end;
if (next_busno <= pci_ctrl->last_busno)
next_busno = pci_ctrl->last_busno+1;
}
pci_bus_count = next_busno;
ret = platform_pcibios_fixup();
if (ret)
return ret;
for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) {
if (pci_ctrl->bus)
pci_bus_add_devices(pci_ctrl->bus);
}
return 0;
}
subsys_initcall(pcibios_init);
void pcibios_fixup_bus(struct pci_bus *bus)
{
if (bus->parent) {
/* This is a subordinate bridge */
pci_read_bridge_bases(bus);
}
}
void pcibios_set_master(struct pci_dev *dev)
{
/* No special bus mastering setup handling */
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
u16 cmd, old_cmd;
int idx;
struct resource *r;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
old_cmd = cmd;
for (idx=0; idx<6; idx++) {
r = &dev->resource[idx];
if (!r->start && r->end) {
pci_err(dev, "can't enable device: resource collisions\n");
return -EINVAL;
}
if (r->flags & IORESOURCE_IO)
cmd |= PCI_COMMAND_IO;
if (r->flags & IORESOURCE_MEM)
cmd |= PCI_COMMAND_MEMORY;
}
if (cmd != old_cmd) {
pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
return 0;
}
/*
* Platform support for /proc/bus/pci/X/Y mmap()s.
* -- paulus.
*/
int pci_iobar_pfn(struct pci_dev *pdev, int bar, struct vm_area_struct *vma)
{
struct pci_controller *pci_ctrl = (struct pci_controller*) pdev->sysdata;
resource_size_t ioaddr = pci_resource_start(pdev, bar);
if (pci_ctrl == 0)
return -EINVAL; /* should never happen */
/* Convert to an offset within this PCI controller */
ioaddr -= (unsigned long)pci_ctrl->io_space.base;
vma->vm_pgoff += (ioaddr + pci_ctrl->io_space.start) >> PAGE_SHIFT;
return 0;
}
|