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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2016 Broadcom
*/
#include <linux/device.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/pci-ecam.h>
#include <linux/slab.h>
/*
* On 64-bit systems, we do a single ioremap for the whole config space
* since we have enough virtual address range available. On 32-bit, we
* ioremap the config space for each bus individually.
*/
static const bool per_bus_mapping = !IS_ENABLED(CONFIG_64BIT);
/*
* Create a PCI config space window
* - reserve mem region
* - alloc struct pci_config_window with space for all mappings
* - ioremap the config space
*/
struct pci_config_window *pci_ecam_create(struct device *dev,
struct resource *cfgres, struct resource *busr,
const struct pci_ecam_ops *ops)
{
unsigned int bus_shift = ops->bus_shift;
struct pci_config_window *cfg;
unsigned int bus_range, bus_range_max, bsz;
struct resource *conflict;
int err;
if (busr->start > busr->end)
return ERR_PTR(-EINVAL);
cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
if (!cfg)
return ERR_PTR(-ENOMEM);
/* ECAM-compliant platforms need not supply ops->bus_shift */
if (!bus_shift)
bus_shift = PCIE_ECAM_BUS_SHIFT;
cfg->parent = dev;
cfg->ops = ops;
cfg->busr.start = busr->start;
cfg->busr.end = busr->end;
cfg->busr.flags = IORESOURCE_BUS;
cfg->bus_shift = bus_shift;
bus_range = resource_size(&cfg->busr);
bus_range_max = resource_size(cfgres) >> bus_shift;
if (bus_range > bus_range_max) {
bus_range = bus_range_max;
cfg->busr.end = busr->start + bus_range - 1;
dev_warn(dev, "ECAM area %pR can only accommodate %pR (reduced from %pR desired)\n",
cfgres, &cfg->busr, busr);
}
bsz = 1 << bus_shift;
cfg->res.start = cfgres->start;
cfg->res.end = cfgres->end;
cfg->res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
cfg->res.name = "PCI ECAM";
conflict = request_resource_conflict(&iomem_resource, &cfg->res);
if (conflict) {
err = -EBUSY;
dev_err(dev, "can't claim ECAM area %pR: address conflict with %s %pR\n",
&cfg->res, conflict->name, conflict);
goto err_exit;
}
if (per_bus_mapping) {
cfg->winp = kcalloc(bus_range, sizeof(*cfg->winp), GFP_KERNEL);
if (!cfg->winp)
goto err_exit_malloc;
} else {
cfg->win = pci_remap_cfgspace(cfgres->start, bus_range * bsz);
if (!cfg->win)
goto err_exit_iomap;
}
if (ops->init) {
err = ops->init(cfg);
if (err)
goto err_exit;
}
dev_info(dev, "ECAM at %pR for %pR\n", &cfg->res, &cfg->busr);
return cfg;
err_exit_iomap:
dev_err(dev, "ECAM ioremap failed\n");
err_exit_malloc:
err = -ENOMEM;
err_exit:
pci_ecam_free(cfg);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(pci_ecam_create);
void pci_ecam_free(struct pci_config_window *cfg)
{
int i;
if (per_bus_mapping) {
if (cfg->winp) {
for (i = 0; i < resource_size(&cfg->busr); i++)
if (cfg->winp[i])
iounmap(cfg->winp[i]);
kfree(cfg->winp);
}
} else {
if (cfg->win)
iounmap(cfg->win);
}
if (cfg->res.parent)
release_resource(&cfg->res);
kfree(cfg);
}
EXPORT_SYMBOL_GPL(pci_ecam_free);
static int pci_ecam_add_bus(struct pci_bus *bus)
{
struct pci_config_window *cfg = bus->sysdata;
unsigned int bsz = 1 << cfg->bus_shift;
unsigned int busn = bus->number;
phys_addr_t start;
if (!per_bus_mapping)
return 0;
if (busn < cfg->busr.start || busn > cfg->busr.end)
return -EINVAL;
busn -= cfg->busr.start;
start = cfg->res.start + busn * bsz;
cfg->winp[busn] = pci_remap_cfgspace(start, bsz);
if (!cfg->winp[busn])
return -ENOMEM;
return 0;
}
static void pci_ecam_remove_bus(struct pci_bus *bus)
{
struct pci_config_window *cfg = bus->sysdata;
unsigned int busn = bus->number;
if (!per_bus_mapping || busn < cfg->busr.start || busn > cfg->busr.end)
return;
busn -= cfg->busr.start;
if (cfg->winp[busn]) {
iounmap(cfg->winp[busn]);
cfg->winp[busn] = NULL;
}
}
/*
* Function to implement the pci_ops ->map_bus method
*/
void __iomem *pci_ecam_map_bus(struct pci_bus *bus, unsigned int devfn,
int where)
{
struct pci_config_window *cfg = bus->sysdata;
unsigned int bus_shift = cfg->ops->bus_shift;
unsigned int devfn_shift = cfg->ops->bus_shift - 8;
unsigned int busn = bus->number;
void __iomem *base;
u32 bus_offset, devfn_offset;
if (busn < cfg->busr.start || busn > cfg->busr.end)
return NULL;
busn -= cfg->busr.start;
if (per_bus_mapping) {
base = cfg->winp[busn];
busn = 0;
} else
base = cfg->win;
if (cfg->ops->bus_shift) {
bus_offset = (busn & PCIE_ECAM_BUS_MASK) << bus_shift;
devfn_offset = (devfn & PCIE_ECAM_DEVFN_MASK) << devfn_shift;
where &= PCIE_ECAM_REG_MASK;
return base + (bus_offset | devfn_offset | where);
}
return base + PCIE_ECAM_OFFSET(busn, devfn, where);
}
EXPORT_SYMBOL_GPL(pci_ecam_map_bus);
/* ECAM ops */
const struct pci_ecam_ops pci_generic_ecam_ops = {
.pci_ops = {
.add_bus = pci_ecam_add_bus,
.remove_bus = pci_ecam_remove_bus,
.map_bus = pci_ecam_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
}
};
EXPORT_SYMBOL_GPL(pci_generic_ecam_ops);
#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
/* ECAM ops for 32-bit access only (non-compliant) */
const struct pci_ecam_ops pci_32b_ops = {
.pci_ops = {
.add_bus = pci_ecam_add_bus,
.remove_bus = pci_ecam_remove_bus,
.map_bus = pci_ecam_map_bus,
.read = pci_generic_config_read32,
.write = pci_generic_config_write32,
}
};
/* ECAM ops for 32-bit read only (non-compliant) */
const struct pci_ecam_ops pci_32b_read_ops = {
.pci_ops = {
.add_bus = pci_ecam_add_bus,
.remove_bus = pci_ecam_remove_bus,
.map_bus = pci_ecam_map_bus,
.read = pci_generic_config_read32,
.write = pci_generic_config_write,
}
};
#endif
|
