1 .. SPDX-License-Identifier: GPL-2.0
2
3 ==============================================
4 PCI Non-Transparent Bridge (NTB) Endpoint Func
5 ==============================================
6
7 :Author: Kishon Vijay Abraham I <kishon@ti.com>
8
9 This document is a guide to help users use pci
10 and ntb_hw_epf host driver for NTB functionali
11 be followed in the host side and EP side is gi
12 configuration and internals of NTB using confi
13 Documentation/PCI/endpoint/pci-ntb-function.rs
14
15 Endpoint Device
16 ===============
17
18 Endpoint Controller Devices
19 ---------------------------
20
21 For implementing NTB functionality at least tw
22 are required.
23
24 To find the list of endpoint controller device
25
26 # ls /sys/class/pci_epc/
27 2900000.pcie-ep 2910000.pcie-ep
28
29 If PCI_ENDPOINT_CONFIGFS is enabled::
30
31 # ls /sys/kernel/config/pci_ep/control
32 2900000.pcie-ep 2910000.pcie-ep
33
34
35 Endpoint Function Drivers
36 -------------------------
37
38 To find the list of endpoint function drivers
39
40 # ls /sys/bus/pci-epf/drivers
41 pci_epf_ntb pci_epf_ntb
42
43 If PCI_ENDPOINT_CONFIGFS is enabled::
44
45 # ls /sys/kernel/config/pci_ep/functio
46 pci_epf_ntb pci_epf_ntb
47
48
49 Creating pci-epf-ntb Device
50 ----------------------------
51
52 PCI endpoint function device can be created us
53 pci-epf-ntb device, the following commands can
54
55 # mount -t configfs none /sys/kernel/c
56 # cd /sys/kernel/config/pci_ep/
57 # mkdir functions/pci_epf_ntb/func1
58
59 The "mkdir func1" above creates the pci-epf-nt
60 be probed by pci_epf_ntb driver.
61
62 The PCI endpoint framework populates the direc
63 configurable fields::
64
65 # ls functions/pci_epf_ntb/func1
66 baseclass_code deviceid ms
67 progif_code secondary su
68 cache_line_size interrupt_pin ms
69 revid subclass_code su
70
71 The PCI endpoint function driver populates the
72 when the device is bound to the driver. The pc
73 vendorid with 0xffff and interrupt_pin with 0x
74
75 # cat functions/pci_epf_ntb/func1/vend
76 0xffff
77 # cat functions/pci_epf_ntb/func1/inte
78 0x0001
79
80
81 Configuring pci-epf-ntb Device
82 -------------------------------
83
84 The user can configure the pci-epf-ntb device
85 to change the vendorid and the deviceid, the f
86 commands can be used::
87
88 # echo 0x104c > functions/pci_epf_ntb/
89 # echo 0xb00d > functions/pci_epf_ntb/
90
91 The PCI endpoint framework also automatically
92 function attribute directory. This sub-directo
93 of the function device and is populated with t
94 attributes that can be configured by the user:
95
96 # ls functions/pci_epf_ntb/func1/pci_e
97 db_count mw1 mw2 mw
98 spad_count
99
100 A sample configuration for NTB function is giv
101
102 # echo 4 > functions/pci_epf_ntb/func1
103 # echo 128 > functions/pci_epf_ntb/fun
104 # echo 2 > functions/pci_epf_ntb/func1
105 # echo 0x100000 > functions/pci_epf_nt
106 # echo 0x100000 > functions/pci_epf_nt
107
108 Binding pci-epf-ntb Device to EP Controller
109 --------------------------------------------
110
111 NTB function device should be attached to two
112 connected to the two hosts. Use the 'primary'
113 inside NTB function device to attach one PCI e
114 primary interface and the other PCI endpoint c
115 interface::
116
117 # ln -s controllers/2900000.pcie-ep/ f
118 # ln -s controllers/2910000.pcie-ep/ f
119
120 Once the above step is completed, both the PCI
121 establish a link with the host.
122
123
124 Start the Link
125 --------------
126
127 In order for the endpoint device to establish
128 field should be populated with '1'. For NTB, b
129 should establish link with the host::
130
131 # echo 1 > controllers/2900000.pcie-ep
132 # echo 1 > controllers/2910000.pcie-ep
133
134
135 RootComplex Device
136 ==================
137
138 lspci Output
139 ------------
140
141 Note that the devices listed here correspond t
142 "Creating pci-epf-ntb Device" section above::
143
144 # lspci
145 0000:00:00.0 PCI bridge: Texas Instrum
146 0000:01:00.0 RAM memory: Texas Instrum
147
148
149 Using ntb_hw_epf Device
150 -----------------------
151
152 The host side software follows the standard NT
153 All the existing client side NTB utilities lik
154 Netdev, NTB Ping Pong Test Client and NTB Tool
155 function device.
156
157 For more information on NTB see
158 :doc:`Non-Transparent Bridge <../../driver-api
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