1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __PCI_BRIDGE_EMUL_H__
3#define __PCI_BRIDGE_EMUL_H__
4
5#include <linux/kernel.h>
6
7/* PCI configuration space of a PCI-to-PCI bridge. */
8struct pci_bridge_emul_conf {
9 __le16 vendor;
10 __le16 device;
11 __le16 command;
12 __le16 status;
13 __le32 class_revision;
14 u8 cache_line_size;
15 u8 latency_timer;
16 u8 header_type;
17 u8 bist;
18 __le32 bar[2];
19 u8 primary_bus;
20 u8 secondary_bus;
21 u8 subordinate_bus;
22 u8 secondary_latency_timer;
23 u8 iobase;
24 u8 iolimit;
25 __le16 secondary_status;
26 __le16 membase;
27 __le16 memlimit;
28 __le16 pref_mem_base;
29 __le16 pref_mem_limit;
30 __le32 prefbaseupper;
31 __le32 preflimitupper;
32 __le16 iobaseupper;
33 __le16 iolimitupper;
34 u8 capabilities_pointer;
35 u8 reserve[3];
36 __le32 romaddr;
37 u8 intline;
38 u8 intpin;
39 __le16 bridgectrl;
40};
41
42/* PCI configuration space of the PCIe capabilities */
43struct pci_bridge_emul_pcie_conf {
44 u8 cap_id;
45 u8 next;
46 __le16 cap;
47 __le32 devcap;
48 __le16 devctl;
49 __le16 devsta;
50 __le32 lnkcap;
51 __le16 lnkctl;
52 __le16 lnksta;
53 __le32 slotcap;
54 __le16 slotctl;
55 __le16 slotsta;
56 __le16 rootctl;
57 __le16 rootcap;
58 __le32 rootsta;
59 __le32 devcap2;
60 __le16 devctl2;
61 __le16 devsta2;
62 __le32 lnkcap2;
63 __le16 lnkctl2;
64 __le16 lnksta2;
65 __le32 slotcap2;
66 __le16 slotctl2;
67 __le16 slotsta2;
68};
69
70struct pci_bridge_emul;
71
72typedef enum { PCI_BRIDGE_EMUL_HANDLED,
73 PCI_BRIDGE_EMUL_NOT_HANDLED } pci_bridge_emul_read_status_t;
74
75struct pci_bridge_emul_ops {
76 /*
77 * Called when reading from the regular PCI bridge
78 * configuration space. Return PCI_BRIDGE_EMUL_HANDLED when the
79 * operation has handled the read operation and filled in the
80 * *value, or PCI_BRIDGE_EMUL_NOT_HANDLED when the read should
81 * be emulated by the common code by reading from the
82 * in-memory copy of the configuration space.
83 */
84 pci_bridge_emul_read_status_t (*read_base)(struct pci_bridge_emul *bridge,
85 int reg, u32 *value);
86
87 /*
88 * Same as ->read_base(), except it is for reading from the
89 * PCIe capability configuration space.
90 */
91 pci_bridge_emul_read_status_t (*read_pcie)(struct pci_bridge_emul *bridge,
92 int reg, u32 *value);
93
94 /*
95 * Same as ->read_base(), except it is for reading from the
96 * PCIe extended capability configuration space.
97 */
98 pci_bridge_emul_read_status_t (*read_ext)(struct pci_bridge_emul *bridge,
99 int reg, u32 *value);
100
101 /*
102 * Called when writing to the regular PCI bridge configuration
103 * space. old is the current value, new is the new value being
104 * written, and mask indicates which parts of the value are
105 * being changed.
106 */
107 void (*write_base)(struct pci_bridge_emul *bridge, int reg,
108 u32 old, u32 new, u32 mask);
109
110 /*
111 * Same as ->write_base(), except it is for writing from the
112 * PCIe capability configuration space.
113 */
114 void (*write_pcie)(struct pci_bridge_emul *bridge, int reg,
115 u32 old, u32 new, u32 mask);
116
117 /*
118 * Same as ->write_base(), except it is for writing from the
119 * PCIe extended capability configuration space.
120 */
121 void (*write_ext)(struct pci_bridge_emul *bridge, int reg,
122 u32 old, u32 new, u32 mask);
123};
124
125struct pci_bridge_reg_behavior;
126
127struct pci_bridge_emul {
128 struct pci_bridge_emul_conf conf;
129 struct pci_bridge_emul_pcie_conf pcie_conf;
130 const struct pci_bridge_emul_ops *ops;
131 struct pci_bridge_reg_behavior *pci_regs_behavior;
132 struct pci_bridge_reg_behavior *pcie_cap_regs_behavior;
133 void *data;
134 u8 pcie_start;
135 u8 ssid_start;
136 bool has_pcie;
137 u16 subsystem_vendor_id;
138 u16 subsystem_id;
139};
140
141enum {
142 /*
143 * PCI bridge does not support forwarding of prefetchable memory
144 * requests between primary and secondary buses.
145 */
146 PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD = BIT(0),
147
148 /*
149 * PCI bridge does not support forwarding of IO requests between
150 * primary and secondary buses.
151 */
152 PCI_BRIDGE_EMUL_NO_IO_FORWARD = BIT(1),
153};
154
155int pci_bridge_emul_init(struct pci_bridge_emul *bridge,
156 unsigned int flags);
157void pci_bridge_emul_cleanup(struct pci_bridge_emul *bridge);
158
159int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
160 int size, u32 *value);
161int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
162 int size, u32 value);
163
164#endif /* __PCI_BRIDGE_EMUL_H__ */
165

source code of linux/drivers/pci/pci-bridge-emul.h