xref: /linux/drivers/pci/pci-bridge-emul.h (revision 63307d015b91e626c97bb82e88054af3d0b74643)
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. */
8 struct pci_bridge_emul_conf {
9 	u16 vendor;
10 	u16 device;
11 	u16 command;
12 	u16 status;
13 	u32 class_revision;
14 	u8 cache_line_size;
15 	u8 latency_timer;
16 	u8 header_type;
17 	u8 bist;
18 	u32 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 	u16 secondary_status;
26 	u16 membase;
27 	u16 memlimit;
28 	u16 pref_mem_base;
29 	u16 pref_mem_limit;
30 	u32 prefbaseupper;
31 	u32 preflimitupper;
32 	u16 iobaseupper;
33 	u16 iolimitupper;
34 	u8 capabilities_pointer;
35 	u8 reserve[3];
36 	u32 romaddr;
37 	u8 intline;
38 	u8 intpin;
39 	u16 bridgectrl;
40 };
41 
42 /* PCI configuration space of the PCIe capabilities */
43 struct pci_bridge_emul_pcie_conf {
44 	u8 cap_id;
45 	u8 next;
46 	u16 cap;
47 	u32 devcap;
48 	u16 devctl;
49 	u16 devsta;
50 	u32 lnkcap;
51 	u16 lnkctl;
52 	u16 lnksta;
53 	u32 slotcap;
54 	u16 slotctl;
55 	u16 slotsta;
56 	u16 rootctl;
57 	u16 rsvd;
58 	u32 rootsta;
59 	u32 devcap2;
60 	u16 devctl2;
61 	u16 devsta2;
62 	u32 lnkcap2;
63 	u16 lnkctl2;
64 	u16 lnksta2;
65 	u32 slotcap2;
66 	u16 slotctl2;
67 	u16 slotsta2;
68 };
69 
70 struct pci_bridge_emul;
71 
72 typedef enum { PCI_BRIDGE_EMUL_HANDLED,
73 	       PCI_BRIDGE_EMUL_NOT_HANDLED } pci_bridge_emul_read_status_t;
74 
75 struct 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 	 * Called when writing to the regular PCI bridge configuration
95 	 * space. old is the current value, new is the new value being
96 	 * written, and mask indicates which parts of the value are
97 	 * being changed.
98 	 */
99 	void (*write_base)(struct pci_bridge_emul *bridge, int reg,
100 			   u32 old, u32 new, u32 mask);
101 
102 	/*
103 	 * Same as ->write_base(), except it is for writing from the
104 	 * PCIe capability configuration space.
105 	 */
106 	void (*write_pcie)(struct pci_bridge_emul *bridge, int reg,
107 			   u32 old, u32 new, u32 mask);
108 };
109 
110 struct pci_bridge_reg_behavior;
111 
112 struct pci_bridge_emul {
113 	struct pci_bridge_emul_conf conf;
114 	struct pci_bridge_emul_pcie_conf pcie_conf;
115 	struct pci_bridge_emul_ops *ops;
116 	struct pci_bridge_reg_behavior *pci_regs_behavior;
117 	struct pci_bridge_reg_behavior *pcie_cap_regs_behavior;
118 	void *data;
119 	bool has_pcie;
120 };
121 
122 enum {
123 	PCI_BRIDGE_EMUL_NO_PREFETCHABLE_BAR = BIT(0),
124 };
125 
126 int pci_bridge_emul_init(struct pci_bridge_emul *bridge,
127 			 unsigned int flags);
128 void pci_bridge_emul_cleanup(struct pci_bridge_emul *bridge);
129 
130 int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
131 			      int size, u32 *value);
132 int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
133 			       int size, u32 value);
134 
135 #endif /* __PCI_BRIDGE_EMUL_H__ */
136