xref: /openbmc/qemu/hw/pci/pci_host.c (revision 24496b8d)
1 /*
2  * pci_host.c
3  *
4  * Copyright (c) 2009 Isaku Yamahata <yamahata at valinux co jp>
5  *                    VA Linux Systems Japan K.K.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11 
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16 
17  * You should have received a copy of the GNU General Public License along
18  * with this program; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "hw/pci/pci.h"
23 #include "hw/pci/pci_bridge.h"
24 #include "hw/pci/pci_host.h"
25 #include "hw/pci/pci_bus.h"
26 #include "trace.h"
27 
28 /* debug PCI */
29 //#define DEBUG_PCI
30 
31 #ifdef DEBUG_PCI
32 #define PCI_DPRINTF(fmt, ...) \
33 do { printf("pci_host_data: " fmt , ## __VA_ARGS__); } while (0)
34 #else
35 #define PCI_DPRINTF(fmt, ...)
36 #endif
37 
38 /*
39  * PCI address
40  * bit 16 - 24: bus number
41  * bit  8 - 15: devfun number
42  * bit  0 -  7: offset in configuration space of a given pci device
43  */
44 
45 /* the helper function to get a PCIDevice* for a given pci address */
46 static inline PCIDevice *pci_dev_find_by_addr(PCIBus *bus, uint32_t addr)
47 {
48     uint8_t bus_num = addr >> 16;
49     uint8_t devfn = addr >> 8;
50 
51     return pci_find_device(bus, bus_num, devfn);
52 }
53 
54 static void pci_adjust_config_limit(PCIBus *bus, uint32_t *limit)
55 {
56     if (*limit > PCI_CONFIG_SPACE_SIZE) {
57         if (!pci_bus_allows_extended_config_space(bus)) {
58             *limit = PCI_CONFIG_SPACE_SIZE;
59             return;
60         }
61 
62         if (!pci_bus_is_root(bus)) {
63             PCIDevice *bridge = pci_bridge_get_device(bus);
64             pci_adjust_config_limit(pci_get_bus(bridge), limit);
65         }
66     }
67 }
68 
69 void pci_host_config_write_common(PCIDevice *pci_dev, uint32_t addr,
70                                   uint32_t limit, uint32_t val, uint32_t len)
71 {
72     pci_adjust_config_limit(pci_get_bus(pci_dev), &limit);
73     if (limit <= addr) {
74         return;
75     }
76 
77     assert(len <= 4);
78     /* non-zero functions are only exposed when function 0 is present,
79      * allowing direct removal of unexposed functions.
80      */
81     if (pci_dev->qdev.hotplugged && !pci_get_function_0(pci_dev)) {
82         return;
83     }
84 
85     trace_pci_cfg_write(pci_dev->name, PCI_SLOT(pci_dev->devfn),
86                         PCI_FUNC(pci_dev->devfn), addr, val);
87     pci_dev->config_write(pci_dev, addr, val, MIN(len, limit - addr));
88 }
89 
90 uint32_t pci_host_config_read_common(PCIDevice *pci_dev, uint32_t addr,
91                                      uint32_t limit, uint32_t len)
92 {
93     uint32_t ret;
94 
95     pci_adjust_config_limit(pci_get_bus(pci_dev), &limit);
96     if (limit <= addr) {
97         return ~0x0;
98     }
99 
100     assert(len <= 4);
101     /* non-zero functions are only exposed when function 0 is present,
102      * allowing direct removal of unexposed functions.
103      */
104     if (pci_dev->qdev.hotplugged && !pci_get_function_0(pci_dev)) {
105         return ~0x0;
106     }
107 
108     ret = pci_dev->config_read(pci_dev, addr, MIN(len, limit - addr));
109     trace_pci_cfg_read(pci_dev->name, PCI_SLOT(pci_dev->devfn),
110                        PCI_FUNC(pci_dev->devfn), addr, ret);
111 
112     return ret;
113 }
114 
115 void pci_data_write(PCIBus *s, uint32_t addr, uint32_t val, int len)
116 {
117     PCIDevice *pci_dev = pci_dev_find_by_addr(s, addr);
118     uint32_t config_addr = addr & (PCI_CONFIG_SPACE_SIZE - 1);
119 
120     if (!pci_dev) {
121         return;
122     }
123 
124     PCI_DPRINTF("%s: %s: addr=%02" PRIx32 " val=%08" PRIx32 " len=%d\n",
125                 __func__, pci_dev->name, config_addr, val, len);
126     pci_host_config_write_common(pci_dev, config_addr, PCI_CONFIG_SPACE_SIZE,
127                                  val, len);
128 }
129 
130 uint32_t pci_data_read(PCIBus *s, uint32_t addr, int len)
131 {
132     PCIDevice *pci_dev = pci_dev_find_by_addr(s, addr);
133     uint32_t config_addr = addr & (PCI_CONFIG_SPACE_SIZE - 1);
134     uint32_t val;
135 
136     if (!pci_dev) {
137         return ~0x0;
138     }
139 
140     val = pci_host_config_read_common(pci_dev, config_addr,
141                                       PCI_CONFIG_SPACE_SIZE, len);
142     PCI_DPRINTF("%s: %s: addr=%02"PRIx32" val=%08"PRIx32" len=%d\n",
143                 __func__, pci_dev->name, config_addr, val, len);
144 
145     return val;
146 }
147 
148 static void pci_host_config_write(void *opaque, hwaddr addr,
149                                   uint64_t val, unsigned len)
150 {
151     PCIHostState *s = opaque;
152 
153     PCI_DPRINTF("%s addr " TARGET_FMT_plx " len %d val %"PRIx64"\n",
154                 __func__, addr, len, val);
155     if (addr != 0 || len != 4) {
156         return;
157     }
158     s->config_reg = val;
159 }
160 
161 static uint64_t pci_host_config_read(void *opaque, hwaddr addr,
162                                      unsigned len)
163 {
164     PCIHostState *s = opaque;
165     uint32_t val = s->config_reg;
166 
167     PCI_DPRINTF("%s addr " TARGET_FMT_plx " len %d val %"PRIx32"\n",
168                 __func__, addr, len, val);
169     return val;
170 }
171 
172 static void pci_host_data_write(void *opaque, hwaddr addr,
173                                 uint64_t val, unsigned len)
174 {
175     PCIHostState *s = opaque;
176     PCI_DPRINTF("write addr " TARGET_FMT_plx " len %d val %x\n",
177                 addr, len, (unsigned)val);
178     if (s->config_reg & (1u << 31))
179         pci_data_write(s->bus, s->config_reg | (addr & 3), val, len);
180 }
181 
182 static uint64_t pci_host_data_read(void *opaque,
183                                    hwaddr addr, unsigned len)
184 {
185     PCIHostState *s = opaque;
186     uint32_t val;
187     if (!(s->config_reg & (1U << 31))) {
188         return 0xffffffff;
189     }
190     val = pci_data_read(s->bus, s->config_reg | (addr & 3), len);
191     PCI_DPRINTF("read addr " TARGET_FMT_plx " len %d val %x\n",
192                 addr, len, val);
193     return val;
194 }
195 
196 const MemoryRegionOps pci_host_conf_le_ops = {
197     .read = pci_host_config_read,
198     .write = pci_host_config_write,
199     .endianness = DEVICE_LITTLE_ENDIAN,
200 };
201 
202 const MemoryRegionOps pci_host_conf_be_ops = {
203     .read = pci_host_config_read,
204     .write = pci_host_config_write,
205     .endianness = DEVICE_BIG_ENDIAN,
206 };
207 
208 const MemoryRegionOps pci_host_data_le_ops = {
209     .read = pci_host_data_read,
210     .write = pci_host_data_write,
211     .endianness = DEVICE_LITTLE_ENDIAN,
212 };
213 
214 const MemoryRegionOps pci_host_data_be_ops = {
215     .read = pci_host_data_read,
216     .write = pci_host_data_write,
217     .endianness = DEVICE_BIG_ENDIAN,
218 };
219 
220 static const TypeInfo pci_host_type_info = {
221     .name = TYPE_PCI_HOST_BRIDGE,
222     .parent = TYPE_SYS_BUS_DEVICE,
223     .abstract = true,
224     .class_size = sizeof(PCIHostBridgeClass),
225     .instance_size = sizeof(PCIHostState),
226 };
227 
228 static void pci_host_register_types(void)
229 {
230     type_register_static(&pci_host_type_info);
231 }
232 
233 type_init(pci_host_register_types)
234