1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Simple, generic PCI host controller driver targeting firmware-initialised |
4 | * systems and virtual machines (e.g. the PCI emulation provided by kvmtool). |
5 | * |
6 | * Copyright (C) 2014 ARM Limited |
7 | * |
8 | * Author: Will Deacon <will.deacon@arm.com> |
9 | */ |
10 | |
11 | #include <linux/kernel.h> |
12 | #include <linux/init.h> |
13 | #include <linux/module.h> |
14 | #include <linux/pci-ecam.h> |
15 | #include <linux/platform_device.h> |
16 | |
17 | static const struct pci_ecam_ops gen_pci_cfg_cam_bus_ops = { |
18 | .bus_shift = 16, |
19 | .pci_ops = { |
20 | .map_bus = pci_ecam_map_bus, |
21 | .read = pci_generic_config_read, |
22 | .write = pci_generic_config_write, |
23 | } |
24 | }; |
25 | |
26 | static bool pci_dw_valid_device(struct pci_bus *bus, unsigned int devfn) |
27 | { |
28 | struct pci_config_window *cfg = bus->sysdata; |
29 | |
30 | /* |
31 | * The Synopsys DesignWare PCIe controller in ECAM mode will not filter |
32 | * type 0 config TLPs sent to devices 1 and up on its downstream port, |
33 | * resulting in devices appearing multiple times on bus 0 unless we |
34 | * filter out those accesses here. |
35 | */ |
36 | if (bus->number == cfg->busr.start && PCI_SLOT(devfn) > 0) |
37 | return false; |
38 | |
39 | return true; |
40 | } |
41 | |
42 | static void __iomem *pci_dw_ecam_map_bus(struct pci_bus *bus, |
43 | unsigned int devfn, int where) |
44 | { |
45 | if (!pci_dw_valid_device(bus, devfn)) |
46 | return NULL; |
47 | |
48 | return pci_ecam_map_bus(bus, devfn, where); |
49 | } |
50 | |
51 | static const struct pci_ecam_ops pci_dw_ecam_bus_ops = { |
52 | .pci_ops = { |
53 | .map_bus = pci_dw_ecam_map_bus, |
54 | .read = pci_generic_config_read, |
55 | .write = pci_generic_config_write, |
56 | } |
57 | }; |
58 | |
59 | static const struct of_device_id gen_pci_of_match[] = { |
60 | { .compatible = "pci-host-cam-generic" , |
61 | .data = &gen_pci_cfg_cam_bus_ops }, |
62 | |
63 | { .compatible = "pci-host-ecam-generic" , |
64 | .data = &pci_generic_ecam_ops }, |
65 | |
66 | { .compatible = "marvell,armada8k-pcie-ecam" , |
67 | .data = &pci_dw_ecam_bus_ops }, |
68 | |
69 | { .compatible = "socionext,synquacer-pcie-ecam" , |
70 | .data = &pci_dw_ecam_bus_ops }, |
71 | |
72 | { .compatible = "snps,dw-pcie-ecam" , |
73 | .data = &pci_dw_ecam_bus_ops }, |
74 | |
75 | { }, |
76 | }; |
77 | MODULE_DEVICE_TABLE(of, gen_pci_of_match); |
78 | |
79 | static struct platform_driver gen_pci_driver = { |
80 | .driver = { |
81 | .name = "pci-host-generic" , |
82 | .of_match_table = gen_pci_of_match, |
83 | }, |
84 | .probe = pci_host_common_probe, |
85 | .remove_new = pci_host_common_remove, |
86 | }; |
87 | module_platform_driver(gen_pci_driver); |
88 | |
89 | MODULE_LICENSE("GPL v2" ); |
90 | |