1 .. SPDX-License-Identifier: GPL-2.0 1 .. SPDX-License-Identifier: GPL-2.0
2 2
3 ================= 3 =================
4 Devlink Line card 4 Devlink Line card
5 ================= 5 =================
6 6
7 Background 7 Background
8 ========== 8 ==========
9 9
10 The ``devlink-linecard`` mechanism is targeted 10 The ``devlink-linecard`` mechanism is targeted for manipulation of
11 line cards that serve as a detachable PHY modu 11 line cards that serve as a detachable PHY modules for modular switch
12 system. Following operations are provided: 12 system. Following operations are provided:
13 13
14 * Get a list of supported line card types. 14 * Get a list of supported line card types.
15 * Provision of a slot with specific line car 15 * Provision of a slot with specific line card type.
16 * Get and monitor of line card state and its 16 * Get and monitor of line card state and its change.
17 17
18 Line card according to the type may contain on 18 Line card according to the type may contain one or more gearboxes
19 to mux the lanes with certain speed to multipl 19 to mux the lanes with certain speed to multiple ports with lanes
20 of different speed. Line card ensures N:M mapp 20 of different speed. Line card ensures N:M mapping between
21 the switch ASIC modules and physical front pan 21 the switch ASIC modules and physical front panel ports.
22 22
23 Overview 23 Overview
24 ======== 24 ========
25 25
26 Each line card devlink object is created by de 26 Each line card devlink object is created by device driver,
27 according to the physical line card slots avai 27 according to the physical line card slots available on the device.
28 28
29 Similar to splitter cable, where the device mi 29 Similar to splitter cable, where the device might have no way
30 of detection of the splitter cable geometry, t 30 of detection of the splitter cable geometry, the device
31 might not have a way to detect line card type. 31 might not have a way to detect line card type. For that devices,
32 concept of provisioning is introduced. It allo 32 concept of provisioning is introduced. It allows the user to:
33 33
34 * Provision a line card slot with certain li 34 * Provision a line card slot with certain line card type
35 35
36 - Device driver would instruct the ASIC to 36 - Device driver would instruct the ASIC to prepare all
37 resources accordingly. The device driver 37 resources accordingly. The device driver would
38 create all instances, namely devlink por 38 create all instances, namely devlink port and netdevices
39 that reside on the line card, according 39 that reside on the line card, according to the line card type
40 * Manipulate of line card entities even with 40 * Manipulate of line card entities even without line card
41 being physically connected or powered-up 41 being physically connected or powered-up
42 * Setup splitter cable on line card ports 42 * Setup splitter cable on line card ports
43 43
44 - As on the ordinary ports, user may provi 44 - As on the ordinary ports, user may provision a splitter
45 cable of a certain type, without the nee 45 cable of a certain type, without the need to
46 be physically connected to the port 46 be physically connected to the port
47 * Configure devlink ports and netdevices 47 * Configure devlink ports and netdevices
48 48
49 Netdevice carrier is decided as follows: 49 Netdevice carrier is decided as follows:
50 50
51 * Line card is not inserted or powered-down 51 * Line card is not inserted or powered-down
52 52
53 - The carrier is always down 53 - The carrier is always down
54 * Line card is inserted and powered up 54 * Line card is inserted and powered up
55 55
56 - The carrier is decided as for ordinary p 56 - The carrier is decided as for ordinary port netdevice
57 57
58 Line card state 58 Line card state
59 =============== 59 ===============
60 60
61 The ``devlink-linecard`` mechanism supports th 61 The ``devlink-linecard`` mechanism supports the following line card states:
62 62
63 * ``unprovisioned``: Line card is not provis 63 * ``unprovisioned``: Line card is not provisioned on the slot.
64 * ``unprovisioning``: Line card slot is curr 64 * ``unprovisioning``: Line card slot is currently being unprovisioned.
65 * ``provisioning``: Line card slot is curren 65 * ``provisioning``: Line card slot is currently in a process of being provisioned
66 with a line card type. 66 with a line card type.
67 * ``provisioning_failed``: Provisioning was 67 * ``provisioning_failed``: Provisioning was not successful.
68 * ``provisioned``: Line card slot is provisi 68 * ``provisioned``: Line card slot is provisioned with a type.
69 * ``active``: Line card is powered-up and ac 69 * ``active``: Line card is powered-up and active.
70 70
71 The following diagram provides a general overv 71 The following diagram provides a general overview of ``devlink-linecard``
72 state transitions:: 72 state transitions::
73 73
74 +--- 74 +-------------------------+
75 | 75 | |
76 +----------------------------------> 76 +----------------------------------> unprovisioned |
77 | | 77 | | |
78 | +--- 78 | +--------|-------^--------+
79 | 79 | | |
80 | 80 | | |
81 | +--- 81 | +--------v-------|--------+
82 | | 82 | | |
83 | | 83 | | provisioning |
84 | | 84 | | |
85 | +--- 85 | +------------|------------+
86 | 86 | |
87 | +-------------------- 87 | +-----------------------------+
88 | | 88 | | |
89 | +------------v------------+ +--- 89 | +------------v------------+ +------------v------------+ +-------------------------+
90 | | | | 90 | | | | ----> |
91 +----- provisioning_failed | | 91 +----- provisioning_failed | | provisioned | | active |
92 | | | | 92 | | | | <---- |
93 | +------------^------------+ +--- 93 | +------------^------------+ +------------|------------+ +-------------------------+
94 | | 94 | | |
95 | | 95 | | |
96 | | +--- 96 | | +------------v------------+
97 | | | 97 | | | |
98 | | | 98 | | | unprovisioning |
99 | | | 99 | | | |
100 | | +--- 100 | | +------------|------------+
101 | | 101 | | |
102 | +-------------------- 102 | +-----------------------------+
103 | 103 | |
104 +-------------------------------------- 104 +-----------------------------------------------+
105 105
106 106
107 Example usage 107 Example usage
108 ============= 108 =============
109 109
110 .. code:: shell 110 .. code:: shell
111 111
112 $ devlink lc show [ DEV [ lc LC_INDEX ] ] 112 $ devlink lc show [ DEV [ lc LC_INDEX ] ]
113 $ devlink lc set DEV lc LC_INDEX [ { type 113 $ devlink lc set DEV lc LC_INDEX [ { type LC_TYPE | notype } ]
114 114
115 # Show current line card configuration and 115 # Show current line card configuration and status for all slots:
116 $ devlink lc 116 $ devlink lc
117 117
118 # Set slot 8 to be provisioned with type " 118 # Set slot 8 to be provisioned with type "16x100G":
119 $ devlink lc set pci/0000:01:00.0 lc 8 typ 119 $ devlink lc set pci/0000:01:00.0 lc 8 type 16x100G
120 120
121 # Set slot 8 to be unprovisioned: 121 # Set slot 8 to be unprovisioned:
122 $ devlink lc set pci/0000:01:00.0 lc 8 not 122 $ devlink lc set pci/0000:01:00.0 lc 8 notype
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