linux.git/drivers/pci/remove.c, branch v2.6.27

PCI: add PCI Express ASPM support

2008-04-21T04:47:03+00:00

PCI Express ASPM defines a protocol for PCI Express components in the D0
state to reduce Link power by placing their Links into a low power state
and instructing the other end of the Link to do likewise. This
capability allows hardware-autonomous, dynamic Link power reduction
beyond what is achievable by software-only controlled power management.
However, The device should be configured by software appropriately.
Enabling ASPM will save power, but will introduce device latency.

This patch adds ASPM support in Linux. It introduces a global policy for
ASPM, a sysfs file /sys/module/pcie_aspm/parameters/policy can control
it. The interface can be used as a boot option too. Currently we have
below setting:
        -default, BIOS default setting
        -powersave, highest power saving mode, enable all available ASPM
state and clock power management
        -performance, highest performance, disable ASPM and clock power
management
By default, the 'default' policy is used currently.

In my test, power difference between powersave mode and performance mode
is about 1.3w in a system with 3 PCIE links.

Note: some devices might not work well with aspm, either because chipset
issue or device issue. The patch provide API (pci_disable_link_state),
driver can disable ASPM for specific device.

Signed-off-by: Shaohua Li 
Signed-off-by: Greg Kroah-Hartman

PCI: remove global list of PCI devices

2008-04-21T04:47:02+00:00

This patch finally removes the global list of PCI devices.  We are
relying entirely on the list held in the driver core now, and do not
need a separate "shadow" list as no one uses it.

Signed-off-by: Greg Kroah-Hartman

PCI: add is_added flag to struct pci_dev

2008-04-21T04:47:00+00:00

This lets us check if the device is really added to the driver core or
not, which is what we need when walking some of the bus lists.  The flag
is there in anticipation of getting rid of the other PCI device list,
which is what we used to check in this situation.

Signed-off-by: Greg Kroah-Hartman

Revert "PCI: PCIE ASPM support"

2008-02-02T19:32:01+00:00

This reverts commit 6c723d5bd89f03fc3ef627d50f89ade054d2ee3b.

It caused build errors on non-x86 platforms, config file confusion, and
even some boot errors on some x86-64 boxes.  All around, not quite ready
for prime-time :(

Cc: Shaohua Li 
Signed-off-by: Greg Kroah-Hartman

PCI: make pci_bus a struct device

2008-02-01T23:04:31+00:00

This moves the pci_bus class device to be a real struct device and at
the same time, place it in the device tree in the correct location.

Note, the old "bridge" symlink is now gone, but this was a non-standard
link and no userspace program used it.  If you need to determine the
device that the bus is on, follow the standard device symlink, or walk
up the device tree.


Signed-off-by: Greg Kroah-Hartman

PCI: PCIE ASPM support

2008-02-01T23:04:30+00:00

PCI Express ASPM defines a protocol for PCI Express components in the D0
state to reduce Link power by placing their Links into a low power state
and instructing the other end of the Link to do likewise. This
capability allows hardware-autonomous, dynamic Link power reduction
beyond what is achievable by software-only controlled power management.
However, The device should be configured by software appropriately.
Enabling ASPM will save power, but will introduce device latency.

This patch adds ASPM support in Linux. It introduces a global policy for
ASPM, a sysfs file /sys/module/pcie_aspm/parameters/policy can control
it. The interface can be used as a boot option too. Currently we have
below setting:
        -default, BIOS default setting
        -powersave, highest power saving mode, enable all available ASPM
state
and clock power management
        -performance, highest performance, disable ASPM and clock power
management
By default, the 'default' policy is used currently.

In my test, power difference between powersave mode and performance mode
is about 1.3w in a system with 3 PCIE links.

Signed-off-by: Shaohua Li 
Signed-off-by: Greg Kroah-Hartman

PCI: add pci_stop_bus_device

2006-09-27T00:43:54+00:00

This patch adds pci_stop_bus_device() which stops a PCI device (detach
the driver, remove from the global list and so on) and any children.
This is needed for ACPI based PCI-to-PCI bridge hot-remove, and it will
be also needed for ACPI based PCI root bridge hot-remove.

Signed-off-by: Kenji Kaneshige 
Signed-off-by: MUNEDA Takahiro 
Signed-off-by: Satoru Takeuchi 
Signed-off-by: Kristen Carlson Accardi 
Signed-off-by: Greg Kroah-Hartman

[PATCH] PCI: fix race with pci_walk_bus and pci_destroy_dev

2006-06-21T19:00:01+00:00

pci_walk_bus has a race with pci_destroy_dev. When cb is called
in pci_walk_bus, pci_destroy_dev might unlink the dev pointed by next.
Later on in the next loop, pointer next becomes NULL and cause
kernel panic.

Below patch against 2.6.17-rc4 fixes it by changing pci_bus_lock (spin_lock)
to pci_bus_sem (rw_semaphore).

Signed-off-by: Zhang Yanmin 
Signed-off-by: Greg Kroah-Hartman

[PATCH] PCI: drivers/pci: some cleanups

2006-01-09T20:13:20+00:00

This patch contains the following cleanups:
- hotplug/pciehp_core.c: make the needlessly global hpdriver_context
                         static
- #if 0 the following unused functions:
  - pci.c: pci_bus_max_busnr()
  - pci.c: pci_max_busnr()
  - proc.c: pci_proc_attach_bus()
  - remove.c: pci_remove_device_safe

Signed-off-by: Adrian Bunk 
Signed-off-by: Greg Kroah-Hartman

[PATCH] acpi bridge hotadd: Make the PCI remove routines safe for failed hot-plug

2005-06-28T04:52:41+00:00

When a root bridge hierarchy is hot-plugged, resource requirements for the new
devices may be greater than what the root bridge is decoding.  In this case,
we want to remove devices that did not get needed resources.  These devices
have been scanned into bus specific lists but not yet added to the global
device list.  Make sure the pci remove functions can handle this case.

Signed-off-by: Rajesh Shah 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman