1 .. SPDX-License-Identifier: GPL-2.0
2
3 =========
4 S/390 PCI
5 =========
6
7 Authors:
8 - Pierre Morel
9
10 Copyright, IBM Corp. 2020
11
12
13 Command line parameters and debugfs entries
14 ===========================================
15
16 Command line parameters
17 -----------------------
18
19 * nomio
20
21 Do not use PCI Mapped I/O (MIO) instructions
22
23 * norid
24
25 Ignore the RID field and force use of one PC
26
27 debugfs entries
28 ---------------
29
30 The S/390 debug feature (s390dbf) generates vi
31
32 * /sys/kernel/debug/s390dbf/pci_*/
33
34 For example:
35
36 - /sys/kernel/debug/s390dbf/pci_msg/sprintf
37 Holds messages from the processing of PCI
38 and setting of global functionality, like
39
40 Change the level of logging to be more or le
41 a number between 0 and 6 to /sys/kernel/deb
42 details, see the documentation on the S/390
43 Documentation/arch/s390/s390dbf.rst.
44
45 Sysfs entries
46 =============
47
48 Entries specific to zPCI functions and entries
49
50 * /sys/bus/pci/slots/XXXXXXXX
51
52 The slot entries are set up using the functi
53 PCI function. The format depicted as XXXXXXX
54 with 0 padding and lower case hexadecimal di
55
56 - /sys/bus/pci/slots/XXXXXXXX/power
57
58 A physical function that currently supports
59 powered off until all virtual functions are
60 echo 0 > /sys/bus/pci/devices/XXXX:XX:XX.X/s
61
62 * /sys/bus/pci/devices/XXXX:XX:XX.X/
63
64 - function_id
65 A zPCI function identifier that uniquely i
66
67 - function_handle
68 Low-level identifier used for a configured
69 It might be useful for debugging.
70
71 - pchid
72 Model-dependent location of the I/O adapte
73
74 - pfgid
75 PCI function group ID, functions that shar
76 use a common identifier.
77 A PCI group defines interrupts, IOMMU, IOT
78
79 - vfn
80 The virtual function number, from 1 to N f
81 0 for physical functions.
82
83 - pft
84 The PCI function type
85
86 - port
87 The port corresponds to the physical port
88 It also gives an indication of the physica
89 is attached to.
90
91 - uid
92 The user identifier (UID) may be defined a
93 configuration or the z/VM or KVM guest con
94 uid_is_unique attribute is 1 the platform
95 within that instance and no devices with t
96 during the lifetime of the system.
97
98 - uid_is_unique
99 Indicates whether the user identifier (UID
100 unique within this Linux instance.
101
102 - pfip/segmentX
103 The segments determine the isolation of a
104 They correspond to the physical path to th
105 The more the segments are different, the m
106
107 Enumeration and hotplug
108 =======================
109
110 The PCI address consists of four parts: domain
111 and is of this form: DDDD:BB:dd.f
112
113 * When not using multi-functions (norid is set
114 support multi-functions):
115
116 - There is only one function per domain.
117
118 - The domain is set from the zPCI function's
119 LPAR creation.
120
121 * When using multi-functions (norid parameter
122 zPCI functions are addressed differently:
123
124 - There is still only one bus per domain.
125
126 - There can be up to 256 functions per bus.
127
128 - The domain part of the address of all func
129 a multi-Function device is set from the zP
130 in the LPAR creation for the function zero
131
132 - New functions will only be ready for use a
133 (the function with devfn 0) has been enume
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.