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-rw-r--r--Documentation/PCI/acpi-info.rst18
1 files changed, 9 insertions, 9 deletions
diff --git a/Documentation/PCI/acpi-info.rst b/Documentation/PCI/acpi-info.rst
index 060217081c79..34c64a5a66ec 100644
--- a/Documentation/PCI/acpi-info.rst
+++ b/Documentation/PCI/acpi-info.rst
@@ -22,9 +22,9 @@ or if the device has INTx interrupts connected by platform interrupt
controllers and a _PRT is needed to describe those connections.
ACPI resource description is done via _CRS objects of devices in the ACPI
-namespace [2].   The _CRS is like a generalized PCI BAR: the OS can read
+namespace [2]. The _CRS is like a generalized PCI BAR: the OS can read
_CRS and figure out what resource is being consumed even if it doesn't have
-a driver for the device [3].  That's important because it means an old OS
+a driver for the device [3]. That's important because it means an old OS
can work correctly even on a system with new devices unknown to the OS.
The new devices might not do anything, but the OS can at least make sure no
resources conflict with them.
@@ -41,15 +41,15 @@ ACPI, that device will have a specific _HID/_CID that tells the OS what
driver to bind to it, and the _CRS tells the OS and the driver where the
device's registers are.
-PCI host bridges are PNP0A03 or PNP0A08 devices.  Their _CRS should
-describe all the address space they consume.  This includes all the windows
+PCI host bridges are PNP0A03 or PNP0A08 devices. Their _CRS should
+describe all the address space they consume. This includes all the windows
they forward down to the PCI bus, as well as registers of the host bridge
-itself that are not forwarded to PCI.  The host bridge registers include
+itself that are not forwarded to PCI. The host bridge registers include
things like secondary/subordinate bus registers that determine the bus
range below the bridge, window registers that describe the apertures, etc.
These are all device-specific, non-architected things, so the only way a
PNP0A03/PNP0A08 driver can manage them is via _PRS/_CRS/_SRS, which contain
-the device-specific details.  The host bridge registers also include ECAM
+the device-specific details. The host bridge registers also include ECAM
space, since it is consumed by the host bridge.
ACPI defines a Consumer/Producer bit to distinguish the bridge registers
@@ -66,7 +66,7 @@ the PNP0A03/PNP0A08 device itself. The workaround was to describe the
bridge registers (including ECAM space) in PNP0C02 catch-all devices [6].
With the exception of ECAM, the bridge register space is device-specific
anyway, so the generic PNP0A03/PNP0A08 driver (pci_root.c) has no need to
-know about it.  
+know about it.
New architectures should be able to use "Consumer" Extended Address Space
descriptors in the PNP0A03 device for bridge registers, including ECAM,
@@ -75,9 +75,9 @@ ia64 kernels assume all address space descriptors, including "Consumer"
Extended Address Space ones, are windows, so it would not be safe to
describe bridge registers this way on those architectures.
-PNP0C02 "motherboard" devices are basically a catch-all.  There's no
+PNP0C02 "motherboard" devices are basically a catch-all. There's no
programming model for them other than "don't use these resources for
-anything else."  So a PNP0C02 _CRS should claim any address space that is
+anything else." So a PNP0C02 _CRS should claim any address space that is
(1) not claimed by _CRS under any other device object in the ACPI namespace
and (2) should not be assigned by the OS to something else.