X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Fpci.txt;h=72b20c63959651ce7be7dad2f2e854c983f660e0;hb=3287629eff75c7323e875b942be82f7ac6ca18da;hp=e2c9d0a0c43de9de21efbbc5c6e74fe7f544aa06;hpb=5cefcab3db2b13093480f2a42bf081574dd72d3d;p=linux-2.6-omap-h63xx.git

diff --git a/Documentation/pci.txt b/Documentation/pci.txt
index e2c9d0a0c43..72b20c63959 100644
--- a/Documentation/pci.txt
+++ b/Documentation/pci.txt
@@ -113,9 +113,6 @@ initialization with a pointer to a structure describing the driver
 		(Please see Documentation/power/pci.txt for descriptions
 		of PCI Power Management and the related functions.)
 
-	enable_wake	Enable device to generate wake events from a low power
-			state.
-
 	shutdown	Hook into reboot_notifier_list (kernel/sys.c).
 			Intended to stop any idling DMA operations.
 			Useful for enabling wake-on-lan (NIC) or changing
@@ -277,8 +274,6 @@ the PCI device by calling pci_enable_device(). This will:
 	o allocate an IRQ (if BIOS did not).
 
 NOTE: pci_enable_device() can fail! Check the return value.
-NOTE2: Also see pci_enable_device_bars() below. Drivers can
-    attempt to enable only a subset of BARs they need.
 
 [ OS BUG: we don't check resource allocations before enabling those
   resources. The sequence would make more sense if we called
@@ -299,7 +294,10 @@ If the PCI device can use the PCI Memory-Write-Invalidate transaction,
 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.
 Check the return value of pci_set_mwi() as not all architectures
-or chip-sets may support Memory-Write-Invalidate.
+or chip-sets may support Memory-Write-Invalidate.  Alternatively,
+if Mem-Wr-Inval would be nice to have but is not required, call
+pci_try_set_mwi() to have the system do its best effort at enabling
+Mem-Wr-Inval.
 
 
 3.2 Request MMIO/IOP resources
@@ -373,7 +371,7 @@ E.g. clearing pending interrupts.
 
 3.6 Register IRQ handler
 ~~~~~~~~~~~~~~~~~~~~~~~~
-While calling request_irq() is the the last step described here,
+While calling request_irq() is the last step described here,
 this is often just another intermediate step to initialize a device.
 This step can often be deferred until the device is opened for use.
 
@@ -605,40 +603,7 @@ device lists. This is still possible but discouraged.
 
 
 
-10. pci_enable_device_bars() and Legacy I/O Port space
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Large servers may not be able to provide I/O port resources to all PCI
-devices. I/O Port space is only 64KB on Intel Architecture[1] and is
-likely also fragmented since the I/O base register of PCI-to-PCI
-bridge will usually be aligned to a 4KB boundary[2]. On such systems,
-pci_enable_device() and pci_request_region() will fail when
-attempting to enable I/O Port regions that don't have I/O Port
-resources assigned.
-
-Fortunately, many PCI devices which request I/O Port resources also
-provide access to the same registers via MMIO BARs. These devices can
-be handled without using I/O port space and the drivers typically
-offer a CONFIG_ option to only use MMIO regions
-(e.g. CONFIG_TULIP_MMIO). PCI devices typically provide I/O port
-interface for legacy OSes and will work when I/O port resources are not
-assigned. The "PCI Local Bus Specification Revision 3.0" discusses
-this on p.44, "IMPLEMENTATION NOTE".
-
-If your PCI device driver doesn't need I/O port resources assigned to
-I/O Port BARs, you should use pci_enable_device_bars() instead of
-pci_enable_device() in order not to enable I/O port regions for the
-corresponding devices. In addition, you should use
-pci_request_selected_regions() and pci_release_selected_regions()
-instead of pci_request_regions()/pci_release_regions() in order not to
-request/release I/O port regions for the corresponding devices.
-
-[1] Some systems support 64KB I/O port space per PCI segment.
-[2] Some PCI-to-PCI bridges support optional 1KB aligned I/O base.
-
-
-
-11. MMIO Space and "Write Posting"
+10. MMIO Space and "Write Posting"
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Converting a driver from using I/O Port space to using MMIO space