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-rw-r--r--Documentation/filesystems/index.rst1
-rw-r--r--Documentation/filesystems/sysfs-pci.rst (renamed from Documentation/filesystems/sysfs-pci.txt)23
2 files changed, 16 insertions, 8 deletions
diff --git a/Documentation/filesystems/index.rst b/Documentation/filesystems/index.rst
index 5fb2b2166204..7afb58dff43b 100644
--- a/Documentation/filesystems/index.rst
+++ b/Documentation/filesystems/index.rst
@@ -34,6 +34,7 @@ algorithms work.
quota
seq_file
sharedsubtree
+ sysfs-pci
automount-support
diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.rst
index 06f1d64c6f70..a265f3e2cc80 100644
--- a/Documentation/filesystems/sysfs-pci.txt
+++ b/Documentation/filesystems/sysfs-pci.rst
@@ -1,8 +1,11 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+============================================
Accessing PCI device resources through sysfs
---------------------------------------------
+============================================
sysfs, usually mounted at /sys, provides access to PCI resources on platforms
-that support it. For example, a given bus might look like this:
+that support it. For example, a given bus might look like this::
/sys/devices/pci0000:17
|-- 0000:17:00.0
@@ -30,8 +33,9 @@ This bus contains a single function device in slot 0. The domain and bus
numbers are reproduced for convenience. Under the device directory are several
files, each with their own function.
+ =================== =====================================================
file function
- ---- --------
+ =================== =====================================================
class PCI class (ascii, ro)
config PCI config space (binary, rw)
device PCI device (ascii, ro)
@@ -40,13 +44,16 @@ files, each with their own function.
local_cpus nearby CPU mask (cpumask, ro)
remove remove device from kernel's list (ascii, wo)
resource PCI resource host addresses (ascii, ro)
- resource0..N PCI resource N, if present (binary, mmap, rw[1])
+ resource0..N PCI resource N, if present (binary, mmap, rw\ [1]_)
resource0_wc..N_wc PCI WC map resource N, if prefetchable (binary, mmap)
revision PCI revision (ascii, ro)
rom PCI ROM resource, if present (binary, ro)
subsystem_device PCI subsystem device (ascii, ro)
subsystem_vendor PCI subsystem vendor (ascii, ro)
vendor PCI vendor (ascii, ro)
+ =================== =====================================================
+
+::
ro - read only file
rw - file is readable and writable
@@ -56,7 +63,7 @@ files, each with their own function.
binary - file contains binary data
cpumask - file contains a cpumask type
-[1] rw for RESOURCE_IO (I/O port) regions only
+.. [1] rw for RESOURCE_IO (I/O port) regions only
The read only files are informational, writes to them will be ignored, with
the exception of the 'rom' file. Writable files can be used to perform
@@ -67,11 +74,11 @@ don't support mmapping of certain resources, so be sure to check the return
value from any attempted mmap. The most notable of these are I/O port
resources, which also provide read/write access.
-The 'enable' file provides a counter that indicates how many times the device
+The 'enable' file provides a counter that indicates how many times the device
has been enabled. If the 'enable' file currently returns '4', and a '1' is
echoed into it, it will then return '5'. Echoing a '0' into it will decrease
the count. Even when it returns to 0, though, some of the initialisation
-may not be reversed.
+may not be reversed.
The 'rom' file is special in that it provides read-only access to the device's
ROM file, if available. It's disabled by default, however, so applications
@@ -93,7 +100,7 @@ Accessing legacy resources through sysfs
Legacy I/O port and ISA memory resources are also provided in sysfs if the
underlying platform supports them. They're located in the PCI class hierarchy,
-e.g.
+e.g.::
/sys/class/pci_bus/0000:17/
|-- bridge -> ../../../devices/pci0000:17