xref: /openbmc/qemu/hw/pci/pcie_host.c (revision 278f064e)
1 /*
2  * pcie_host.c
3  * utility functions for pci express host bridge.
4  *
5  * Copyright (c) 2009 Isaku Yamahata <yamahata at valinux co jp>
6  *                    VA Linux Systems Japan K.K.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12 
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17 
18  * You should have received a copy of the GNU General Public License along
19  * with this program; if not, see <http://www.gnu.org/licenses/>.
20  */
21 
22 #include "qemu/osdep.h"
23 #include "hw/pci/pci.h"
24 #include "hw/pci/pcie_host.h"
25 #include "qemu/module.h"
26 
27 /* a helper function to get a PCIDevice for a given mmconfig address */
28 static inline PCIDevice *pcie_dev_find_by_mmcfg_addr(PCIBus *s,
29                                                      uint32_t mmcfg_addr)
30 {
31     return pci_find_device(s, PCIE_MMCFG_BUS(mmcfg_addr),
32                            PCIE_MMCFG_DEVFN(mmcfg_addr));
33 }
34 
35 static void pcie_mmcfg_data_write(void *opaque, hwaddr mmcfg_addr,
36                                   uint64_t val, unsigned len)
37 {
38     PCIExpressHost *e = opaque;
39     PCIBus *s = e->pci.bus;
40     PCIDevice *pci_dev = pcie_dev_find_by_mmcfg_addr(s, mmcfg_addr);
41     uint32_t addr;
42     uint32_t limit;
43 
44     if (!pci_dev) {
45         return;
46     }
47     addr = PCIE_MMCFG_CONFOFFSET(mmcfg_addr);
48     limit = pci_config_size(pci_dev);
49     pci_host_config_write_common(pci_dev, addr, limit, val, len);
50 }
51 
52 static uint64_t pcie_mmcfg_data_read(void *opaque,
53                                      hwaddr mmcfg_addr,
54                                      unsigned len)
55 {
56     PCIExpressHost *e = opaque;
57     PCIBus *s = e->pci.bus;
58     PCIDevice *pci_dev = pcie_dev_find_by_mmcfg_addr(s, mmcfg_addr);
59     uint32_t addr;
60     uint32_t limit;
61 
62     if (!pci_dev) {
63         return ~0x0;
64     }
65     addr = PCIE_MMCFG_CONFOFFSET(mmcfg_addr);
66     limit = pci_config_size(pci_dev);
67     return pci_host_config_read_common(pci_dev, addr, limit, len);
68 }
69 
70 static const MemoryRegionOps pcie_mmcfg_ops = {
71     .read = pcie_mmcfg_data_read,
72     .write = pcie_mmcfg_data_write,
73     .endianness = DEVICE_LITTLE_ENDIAN,
74 };
75 
76 static void pcie_host_init(Object *obj)
77 {
78     PCIExpressHost *e = PCIE_HOST_BRIDGE(obj);
79 
80     e->base_addr = PCIE_BASE_ADDR_UNMAPPED;
81     memory_region_init_io(&e->mmio, OBJECT(e), &pcie_mmcfg_ops, e, "pcie-mmcfg-mmio",
82                           PCIE_MMCFG_SIZE_MAX);
83 }
84 
85 void pcie_host_mmcfg_unmap(PCIExpressHost *e)
86 {
87     if (e->base_addr != PCIE_BASE_ADDR_UNMAPPED) {
88         memory_region_del_subregion(get_system_memory(), &e->mmio);
89         e->base_addr = PCIE_BASE_ADDR_UNMAPPED;
90     }
91 }
92 
93 void pcie_host_mmcfg_init(PCIExpressHost *e, uint32_t size)
94 {
95     assert(!(size & (size - 1)));       /* power of 2 */
96     assert(size >= PCIE_MMCFG_SIZE_MIN);
97     assert(size <= PCIE_MMCFG_SIZE_MAX);
98     e->size = size;
99     memory_region_set_size(&e->mmio, e->size);
100 }
101 
102 void pcie_host_mmcfg_map(PCIExpressHost *e, hwaddr addr,
103                          uint32_t size)
104 {
105     pcie_host_mmcfg_init(e, size);
106     e->base_addr = addr;
107     memory_region_add_subregion(get_system_memory(), e->base_addr, &e->mmio);
108 }
109 
110 void pcie_host_mmcfg_update(PCIExpressHost *e,
111                             int enable,
112                             hwaddr addr,
113                             uint32_t size)
114 {
115     memory_region_transaction_begin();
116     pcie_host_mmcfg_unmap(e);
117     if (enable) {
118         pcie_host_mmcfg_map(e, addr, size);
119     }
120     memory_region_transaction_commit();
121 }
122 
123 static const TypeInfo pcie_host_type_info = {
124     .name = TYPE_PCIE_HOST_BRIDGE,
125     .parent = TYPE_PCI_HOST_BRIDGE,
126     .abstract = true,
127     .instance_size = sizeof(PCIExpressHost),
128     .instance_init = pcie_host_init,
129 };
130 
131 static void pcie_host_register_types(void)
132 {
133     type_register_static(&pcie_host_type_info);
134 }
135 
136 type_init(pcie_host_register_types)
137