Loading...
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 | /*
* Simple, generic PCI host controller driver targetting firmware-initialised
* systems and virtual machines (e.g. the PCI emulation provided by kvmtool).
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright (C) 2014 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/platform_device.h>
struct gen_pci_cfg_bus_ops {
u32 bus_shift;
void __iomem *(*map_bus)(struct pci_bus *, unsigned int, int);
};
struct gen_pci_cfg_windows {
struct resource res;
struct resource *bus_range;
void __iomem **win;
const struct gen_pci_cfg_bus_ops *ops;
};
struct gen_pci {
struct pci_host_bridge host;
struct gen_pci_cfg_windows cfg;
struct list_head resources;
};
static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
unsigned int devfn,
int where)
{
struct pci_sys_data *sys = bus->sysdata;
struct gen_pci *pci = sys->private_data;
resource_size_t idx = bus->number - pci->cfg.bus_range->start;
return pci->cfg.win[idx] + ((devfn << 8) | where);
}
static struct gen_pci_cfg_bus_ops gen_pci_cfg_cam_bus_ops = {
.bus_shift = 16,
.map_bus = gen_pci_map_cfg_bus_cam,
};
static void __iomem *gen_pci_map_cfg_bus_ecam(struct pci_bus *bus,
unsigned int devfn,
int where)
{
struct pci_sys_data *sys = bus->sysdata;
struct gen_pci *pci = sys->private_data;
resource_size_t idx = bus->number - pci->cfg.bus_range->start;
return pci->cfg.win[idx] + ((devfn << 12) | where);
}
static struct gen_pci_cfg_bus_ops gen_pci_cfg_ecam_bus_ops = {
.bus_shift = 20,
.map_bus = gen_pci_map_cfg_bus_ecam,
};
static struct pci_ops gen_pci_ops = {
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
static const struct of_device_id gen_pci_of_match[] = {
{ .compatible = "pci-host-cam-generic",
.data = &gen_pci_cfg_cam_bus_ops },
{ .compatible = "pci-host-ecam-generic",
.data = &gen_pci_cfg_ecam_bus_ops },
{ },
};
MODULE_DEVICE_TABLE(of, gen_pci_of_match);
static void gen_pci_release_of_pci_ranges(struct gen_pci *pci)
{
pci_free_resource_list(&pci->resources);
}
static int gen_pci_parse_request_of_pci_ranges(struct gen_pci *pci)
{
int err, res_valid = 0;
struct device *dev = pci->host.dev.parent;
struct device_node *np = dev->of_node;
resource_size_t iobase;
struct resource_entry *win;
err = of_pci_get_host_bridge_resources(np, 0, 0xff, &pci->resources,
&iobase);
if (err)
return err;
resource_list_for_each_entry(win, &pci->resources) {
struct resource *parent, *res = win->res;
switch (resource_type(res)) {
case IORESOURCE_IO:
parent = &ioport_resource;
err = pci_remap_iospace(res, iobase);
if (err) {
dev_warn(dev, "error %d: failed to map resource %pR\n",
err, res);
continue;
}
break;
case IORESOURCE_MEM:
parent = &iomem_resource;
res_valid |= !(res->flags & IORESOURCE_PREFETCH);
break;
case IORESOURCE_BUS:
pci->cfg.bus_range = res;
default:
continue;
}
err = devm_request_resource(dev, parent, res);
if (err)
goto out_release_res;
}
if (!res_valid) {
dev_err(dev, "non-prefetchable memory resource required\n");
err = -EINVAL;
goto out_release_res;
}
return 0;
out_release_res:
gen_pci_release_of_pci_ranges(pci);
return err;
}
static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
{
int err;
u8 bus_max;
resource_size_t busn;
struct resource *bus_range;
struct device *dev = pci->host.dev.parent;
struct device_node *np = dev->of_node;
err = of_address_to_resource(np, 0, &pci->cfg.res);
if (err) {
dev_err(dev, "missing \"reg\" property\n");
return err;
}
/* Limit the bus-range to fit within reg */
bus_max = pci->cfg.bus_range->start +
(resource_size(&pci->cfg.res) >> pci->cfg.ops->bus_shift) - 1;
pci->cfg.bus_range->end = min_t(resource_size_t,
pci->cfg.bus_range->end, bus_max);
pci->cfg.win = devm_kcalloc(dev, resource_size(pci->cfg.bus_range),
sizeof(*pci->cfg.win), GFP_KERNEL);
if (!pci->cfg.win)
return -ENOMEM;
/* Map our Configuration Space windows */
if (!devm_request_mem_region(dev, pci->cfg.res.start,
resource_size(&pci->cfg.res),
"Configuration Space"))
return -ENOMEM;
bus_range = pci->cfg.bus_range;
for (busn = bus_range->start; busn <= bus_range->end; ++busn) {
u32 idx = busn - bus_range->start;
u32 sz = 1 << pci->cfg.ops->bus_shift;
pci->cfg.win[idx] = devm_ioremap(dev,
pci->cfg.res.start + busn * sz,
sz);
if (!pci->cfg.win[idx])
return -ENOMEM;
}
return 0;
}
static int gen_pci_setup(int nr, struct pci_sys_data *sys)
{
struct gen_pci *pci = sys->private_data;
list_splice_init(&pci->resources, &sys->resources);
return 1;
}
static int gen_pci_probe(struct platform_device *pdev)
{
int err;
const char *type;
const struct of_device_id *of_id;
const int *prop;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
struct hw_pci hw = {
.nr_controllers = 1,
.private_data = (void **)&pci,
.setup = gen_pci_setup,
.map_irq = of_irq_parse_and_map_pci,
.ops = &gen_pci_ops,
};
if (!pci)
return -ENOMEM;
type = of_get_property(np, "device_type", NULL);
if (!type || strcmp(type, "pci")) {
dev_err(dev, "invalid \"device_type\" %s\n", type);
return -EINVAL;
}
prop = of_get_property(of_chosen, "linux,pci-probe-only", NULL);
if (prop) {
if (*prop)
pci_add_flags(PCI_PROBE_ONLY);
else
pci_clear_flags(PCI_PROBE_ONLY);
}
of_id = of_match_node(gen_pci_of_match, np);
pci->cfg.ops = of_id->data;
gen_pci_ops.map_bus = pci->cfg.ops->map_bus;
pci->host.dev.parent = dev;
INIT_LIST_HEAD(&pci->host.windows);
INIT_LIST_HEAD(&pci->resources);
/* Parse our PCI ranges and request their resources */
err = gen_pci_parse_request_of_pci_ranges(pci);
if (err)
return err;
/* Parse and map our Configuration Space windows */
err = gen_pci_parse_map_cfg_windows(pci);
if (err) {
gen_pci_release_of_pci_ranges(pci);
return err;
}
pci_common_init_dev(dev, &hw);
return 0;
}
static struct platform_driver gen_pci_driver = {
.driver = {
.name = "pci-host-generic",
.of_match_table = gen_pci_of_match,
},
.probe = gen_pci_probe,
};
module_platform_driver(gen_pci_driver);
MODULE_DESCRIPTION("Generic PCI host driver");
MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");
MODULE_LICENSE("GPL v2");
|