xref: /openbmc/qemu/hw/pci/pci_host.c (revision 4e6b1384)
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 "qemu/module.h"
26 #include "hw/pci/pci_bus.h"
27 #include "trace.h"
28 
29 /* debug PCI */
30 //#define DEBUG_PCI
31 
32 #ifdef DEBUG_PCI
33 #define PCI_DPRINTF(fmt, ...) \
34 do { printf("pci_host_data: " fmt , ## __VA_ARGS__); } while (0)
35 #else
36 #define PCI_DPRINTF(fmt, ...)
37 #endif
38 
39 /*
40  * PCI address
41  * bit 16 - 24: bus number
42  * bit  8 - 15: devfun number
43  * bit  0 -  7: offset in configuration space of a given pci device
44  */
45 
46 /* the helper function to get a PCIDevice* for a given pci address */
47 static inline PCIDevice *pci_dev_find_by_addr(PCIBus *bus, uint32_t addr)
48 {
49     uint8_t bus_num = addr >> 16;
50     uint8_t devfn = addr >> 8;
51 
52     return pci_find_device(bus, bus_num, devfn);
53 }
54 
55 static void pci_adjust_config_limit(PCIBus *bus, uint32_t *limit)
56 {
57     if ((*limit > PCI_CONFIG_SPACE_SIZE) &&
58         !pci_bus_allows_extended_config_space(bus)) {
59         *limit = PCI_CONFIG_SPACE_SIZE;
60     }
61 }
62 
63 void pci_host_config_write_common(PCIDevice *pci_dev, uint32_t addr,
64                                   uint32_t limit, uint32_t val, uint32_t len)
65 {
66     pci_adjust_config_limit(pci_get_bus(pci_dev), &limit);
67     if (limit <= addr) {
68         return;
69     }
70 
71     assert(len <= 4);
72     /* non-zero functions are only exposed when function 0 is present,
73      * allowing direct removal of unexposed functions.
74      */
75     if (pci_dev->qdev.hotplugged && !pci_get_function_0(pci_dev)) {
76         return;
77     }
78 
79     trace_pci_cfg_write(pci_dev->name, PCI_SLOT(pci_dev->devfn),
80                         PCI_FUNC(pci_dev->devfn), addr, val);
81     pci_dev->config_write(pci_dev, addr, val, MIN(len, limit - addr));
82 }
83 
84 uint32_t pci_host_config_read_common(PCIDevice *pci_dev, uint32_t addr,
85                                      uint32_t limit, uint32_t len)
86 {
87     uint32_t ret;
88 
89     pci_adjust_config_limit(pci_get_bus(pci_dev), &limit);
90     if (limit <= addr) {
91         return ~0x0;
92     }
93 
94     assert(len <= 4);
95     /* non-zero functions are only exposed when function 0 is present,
96      * allowing direct removal of unexposed functions.
97      */
98     if (pci_dev->qdev.hotplugged && !pci_get_function_0(pci_dev)) {
99         return ~0x0;
100     }
101 
102     ret = pci_dev->config_read(pci_dev, addr, MIN(len, limit - addr));
103     trace_pci_cfg_read(pci_dev->name, PCI_SLOT(pci_dev->devfn),
104                        PCI_FUNC(pci_dev->devfn), addr, ret);
105 
106     return ret;
107 }
108 
109 void pci_data_write(PCIBus *s, uint32_t addr, uint32_t val, unsigned len)
110 {
111     PCIDevice *pci_dev = pci_dev_find_by_addr(s, addr);
112     uint32_t config_addr = addr & (PCI_CONFIG_SPACE_SIZE - 1);
113 
114     if (!pci_dev) {
115         return;
116     }
117 
118     pci_host_config_write_common(pci_dev, config_addr, PCI_CONFIG_SPACE_SIZE,
119                                  val, len);
120 }
121 
122 uint32_t pci_data_read(PCIBus *s, uint32_t addr, unsigned len)
123 {
124     PCIDevice *pci_dev = pci_dev_find_by_addr(s, addr);
125     uint32_t config_addr = addr & (PCI_CONFIG_SPACE_SIZE - 1);
126 
127     if (!pci_dev) {
128         return ~0x0;
129     }
130 
131     return pci_host_config_read_common(pci_dev, config_addr,
132                                        PCI_CONFIG_SPACE_SIZE, len);
133 }
134 
135 static void pci_host_config_write(void *opaque, hwaddr addr,
136                                   uint64_t val, unsigned len)
137 {
138     PCIHostState *s = opaque;
139 
140     PCI_DPRINTF("%s addr " TARGET_FMT_plx " len %d val %"PRIx64"\n",
141                 __func__, addr, len, val);
142     if (addr != 0 || len != 4) {
143         return;
144     }
145     s->config_reg = val;
146 }
147 
148 static uint64_t pci_host_config_read(void *opaque, hwaddr addr,
149                                      unsigned len)
150 {
151     PCIHostState *s = opaque;
152     uint32_t val = s->config_reg;
153 
154     PCI_DPRINTF("%s addr " TARGET_FMT_plx " len %d val %"PRIx32"\n",
155                 __func__, addr, len, val);
156     return val;
157 }
158 
159 static void pci_host_data_write(void *opaque, hwaddr addr,
160                                 uint64_t val, unsigned len)
161 {
162     PCIHostState *s = opaque;
163 
164     if (s->config_reg & (1u << 31))
165         pci_data_write(s->bus, s->config_reg | (addr & 3), val, len);
166 }
167 
168 static uint64_t pci_host_data_read(void *opaque,
169                                    hwaddr addr, unsigned len)
170 {
171     PCIHostState *s = opaque;
172 
173     if (!(s->config_reg & (1U << 31))) {
174         return 0xffffffff;
175     }
176     return pci_data_read(s->bus, s->config_reg | (addr & 3), len);
177 }
178 
179 const MemoryRegionOps pci_host_conf_le_ops = {
180     .read = pci_host_config_read,
181     .write = pci_host_config_write,
182     .endianness = DEVICE_LITTLE_ENDIAN,
183 };
184 
185 const MemoryRegionOps pci_host_conf_be_ops = {
186     .read = pci_host_config_read,
187     .write = pci_host_config_write,
188     .endianness = DEVICE_BIG_ENDIAN,
189 };
190 
191 const MemoryRegionOps pci_host_data_le_ops = {
192     .read = pci_host_data_read,
193     .write = pci_host_data_write,
194     .endianness = DEVICE_LITTLE_ENDIAN,
195 };
196 
197 const MemoryRegionOps pci_host_data_be_ops = {
198     .read = pci_host_data_read,
199     .write = pci_host_data_write,
200     .endianness = DEVICE_BIG_ENDIAN,
201 };
202 
203 static const TypeInfo pci_host_type_info = {
204     .name = TYPE_PCI_HOST_BRIDGE,
205     .parent = TYPE_SYS_BUS_DEVICE,
206     .abstract = true,
207     .class_size = sizeof(PCIHostBridgeClass),
208     .instance_size = sizeof(PCIHostState),
209 };
210 
211 static void pci_host_register_types(void)
212 {
213     type_register_static(&pci_host_type_info);
214 }
215 
216 type_init(pci_host_register_types)
217