Re: [PATCH] PCI and sysfs fixes for 2.5.74

Greg KH (greg@kroah.com)
Thu, 3 Jul 2003 19:09:12 -0700


ChangeSet 1.1363, 2003/07/03 15:50:39-07:00, willy@debian.org

[PATCH] PCI: Improve documentation
Fix some grammar problems
Add a note about Fast Back to Back support
Change the slot_name recommendation to pci_name().

Documentation/pci.txt | 12 ++++++++----
1 files changed, 8 insertions(+), 4 deletions(-)

diff -Nru a/Documentation/pci.txt b/Documentation/pci.txt
--- a/Documentation/pci.txt Thu Jul 3 18:17:12 2003
+++ b/Documentation/pci.txt Thu Jul 3 18:17:12 2003
@@ -7,14 +7,14 @@
Different PCI devices have different requirements and different bugs --
because of this, the PCI support layer in Linux kernel is not as trivial
as one would wish. This short pamphlet tries to help all potential driver
-authors to find their way through the deep forests of PCI handling.
+authors find their way through the deep forests of PCI handling.


0. Structure of PCI drivers
~~~~~~~~~~~~~~~~~~~~~~~~~~~
There exist two kinds of PCI drivers: new-style ones (which leave most of
probing for devices to the PCI layer and support online insertion and removal
-of devices [thus supporting PCI, hot-pluggable PCI and CardBus in single
+of devices [thus supporting PCI, hot-pluggable PCI and CardBus in a single
driver]) and old-style ones which just do all the probing themselves. Unless
you have a very good reason to do so, please don't use the old way of probing
in any new code. After the driver finds the devices it wishes to operate
@@ -174,7 +174,7 @@
the latency timer value if it's set to something bogus by the BIOS.

If you want to use the PCI Memory-Write-Invalidate transaction,
-call pci_set_mwi(). This enables bit PCI_COMMAND bit for Mem-Wr-Inval
+call pci_set_mwi(). This enables the PCI_COMMAND bit for Mem-Wr-Inval
and also ensures that the cache line size register is set correctly.
Make sure to check the return value of pci_set_mwi(), not all architectures
may support Memory-Write-Invalidate.
@@ -236,7 +236,7 @@
7. Miscellaneous hints
~~~~~~~~~~~~~~~~~~~~~~
When displaying PCI slot names to the user (for example when a driver wants
-to tell the user what card has it found), please use pci_dev->slot_name
+to tell the user what card has it found), please use pci_name(pci_dev)
for this purpose.

Always refer to the PCI devices by a pointer to the pci_dev structure.
@@ -247,6 +247,10 @@

If you're going to use PCI bus mastering DMA, take a look at
Documentation/DMA-mapping.txt.
+
+Don't try to turn on Fast Back to Back writes in your driver. All devices
+on the bus need to be capable of doing it, so this is something which needs
+to be handled by platform and generic code, not individual drivers.


8. Obsolete functions

-
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