Commit 215e871a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6 

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6: (64 commits)
  PCI: make pci_bus a struct device
  PCI: fix codingstyle issues in include/linux/pci.h
  PCI: fix codingstyle issues in drivers/pci/pci.h
  PCI: PCIE ASPM support
  PCI: Fix fakephp deadlock
  PCI: modify SB700 SATA MSI quirk
  PCI: Run ACPI _OSC method on root bridges only
  PCI ACPI: AER driver should only register PCIe devices with _OSC
  PCI ACPI: Added a function to register _OSC with only PCIe devices.
  PCI: constify function pointer tables
  PCI: Convert drivers/pci/proc.c to use unlocked_ioctl
  pciehp: block new requests from the device before power off
  pciehp: workaround against Bad DLLP during power off
  pciehp: wait for 1000ms before LED operation after power off
  PCI: Remove pci_enable_device_bars() from documentation
  PCI: Remove pci_enable_device_bars()
  PCI: Remove users of pci_enable_device_bars()
  PCI: Add pci_enable_device_{io,mem} intefaces
  PCI: avoid save the same type of cap multiple times
  PCI: correctly initialize a structure for pcie_save_pcix_state()
  ...
parents b6cf160c fd7d1ced

Documentation/pci.txt

+1 −36
Original line number Diff line number Diff line
@@ -274,8 +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
@@ -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

arch/alpha/Kconfig

+0 −5
Original line number Diff line number Diff line
@@ -318,11 +318,6 @@ config PCI 
	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or

	  VESA. If you have PCI, say Y, otherwise N.



	  The PCI-HOWTO, available from

	  <http://www.tldp.org/docs.html#howto>, contains valuable

	  information about which PCI hardware does work under Linux and which

	  doesn't.



config PCI_DOMAINS

	bool

	default y

arch/arm/Kconfig

+0 −5
Original line number Diff line number Diff line
@@ -577,11 +577,6 @@ config PCI 
	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or

	  VESA. If you have PCI, say Y, otherwise N.



	  The PCI-HOWTO, available from

	  <http://www.tldp.org/docs.html#howto>, contains valuable

	  information about which PCI hardware does work under Linux and which

	  doesn't.



config PCI_SYSCALL

	def_bool PCI

arch/frv/Kconfig

+0 −5
Original line number Diff line number Diff line
@@ -322,11 +322,6 @@ config PCI 
	  onboard. If you have one of these boards and you wish to use the PCI

	  facilities, say Y here.



	  The PCI-HOWTO, available from

	  <http://www.tldp.org/docs.html#howto>, contains valuable

	  information about which PCI hardware does work under Linux and which

	  doesn't.



config RESERVE_DMA_COHERENT

	bool "Reserve DMA coherent memory"

	depends on PCI && !MMU

arch/m32r/Kconfig

+0 −5
Original line number Diff line number Diff line
@@ -359,11 +359,6 @@ config PCI 
	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or

	  VESA. If you have PCI, say Y, otherwise N.



	  The PCI-HOWTO, available from

	  <http://www.linuxdoc.org/docs.html#howto>, contains valuable

	  information about which PCI hardware does work under Linux and which

	  doesn't.



choice

	prompt "PCI access mode"

	depends on PCI

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