linux-toradex.git/drivers/pci/hotplug, branch v3.2.8

PCI: Set device power state to PCI_D0 for device without native PM support

2011-12-14T16:26:42+00:00

During test of one IB card with guest VM, found that, msi is not
initialized properly.

It turns out __write_msi_msg will do nothing if device current_state is
not PCI_D0.  And, that pci device does not have pm_cap in guest VM.

There is an error in setting of power state to PCI_D0 in
pci_enable_device(), but error is not returned for this.  Following is
code flow:

pci_enable_device() -->   __pci_enable_device_flags() -->
do_pci_enable_device() -->   pci_set_power_state() -->
__pci_start_power_transition()

We have following condition inside __pci_start_power_transition():
         if (platform_pci_power_manageable(dev)) {
                 error = platform_pci_set_power_state(dev, state);
                 if (!error)
                         pci_update_current_state(dev, state);
         } else {
                 error = -ENODEV;
                 /* Fall back to PCI_D0 if native PM is not supported */
                 if (!dev->pm_cap)
                         dev->current_state = PCI_D0;
         }

Here, from platform_pci_set_power_state(), acpi_pci_set_power_state() is
getting called and that is failing with ENODEV because of following
condition:

         if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0",&tmp)))
                 return -ENODEV;

Because of that, pci_update_current_state() is not getting called.

With this patch, if device power state can not be set via
platform_pci_set_power_state and that device does not have native pm
support, then PCI device power state will be set to PCI_D0.

-v2: This also reverts 47e9037ac16637cd7f12b8790ea7ce6680e42168, as it's
     not needed after this change.

Acked-by: "Rafael J. Wysocki" 
Signed-off-by: Ajaykumar Hotchandani
Signed-off-by: Yinghai Lu
Signed-off-by: Jesse Barnes

PCI hotplug: Always allow acpiphp to handle non-PCIe bridges

2011-12-13T18:41:23+00:00

Commit 0d52f54e2ef64c189dedc332e680b2eb4a34590a (PCI / ACPI: Make
acpiphp ignore root bridges using PCIe native hotplug) added code
that made the acpiphp driver completely ignore PCIe root complexes
for which the kernel had been granted control of the native PCIe
hotplug feature by the BIOS through _OSC.  Unfortunately, however,
this was a mistake, because on some systems there were PCI bridges
supporting PCI (non-PCIe) hotplug under such root complexes and
those bridges should have been handled by acpiphp.

For this reason, revert the changes made by the commit mentioned
above and make register_slot() in drivers/pci/hotplug/acpiphp_glue.c
avoid registering hotplug slots for PCIe ports that belong to
root complexes with native PCIe hotplug enabled (which means that
the BIOS has granted the kernel control of this feature for the
given root complex).  This is reported to address the original
issue fixed by commit 0d52f54e2ef64c189dedc332e680b2eb4a34590a and
to work on the system where that commit broke things.

Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Jesse Barnes

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci

2011-11-23T22:58:46+00:00

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
  PCI hotplug: shpchp: don't blindly claim non-AMD 0x7450 device IDs
  PCI: pciehp: wait 100 ms after Link Training check
  PCI: pciehp: wait 1000 ms before Link Training check
  PCI: pciehp: Retrieve link speed after link is trained
  PCI: Let PCI_PRI depend on PCI
  PCI: Fix compile errors with PCI_ATS and !PCI_IOV
  PCI / ACPI: Make acpiphp ignore root bridges using PCIe native hotplug

PCI hotplug: shpchp: don't blindly claim non-AMD 0x7450 device IDs

2011-11-14T17:43:14+00:00

Previously we claimed device ID 0x7450, regardless of the vendor, which is
clearly wrong.  Now we'll claim that device ID only for AMD.

I suspect this was just a typo in the original code, but it's possible this
change will break shpchp on non-7450 AMD bridges.  If so, we'll have to fix
them as we find them.

Reference: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=638863
Reported-by: Ralf Jung 
Cc: Joerg Roedel 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Jesse Barnes

PCI: pciehp: wait 100 ms after Link Training check

2011-11-11T17:31:43+00:00

If the port supports Link speeds greater than 5.0 GT/s, we must wait
for 100 ms after Link training completes before sending configuration
request.

Acked-by: Yinghai Lu 
Tested-by: Yinghai Lu 
Signed-off-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

PCI: pciehp: wait 1000 ms before Link Training check

2011-11-11T17:31:34+00:00

We need to wait for 1000 ms after Data Link Layer Link Active (DLLLA)
bit reads 1b before sending configuration request. Currently pciehp
does this wait after checking Link Training (LT) bit. But we need it
before checking LT bit because LT is still set even after DLLLA bit is
set on some platforms.

Acked-by: Yinghai Lu 
Tested-by: Yinghai Lu 
Signed-off-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

PCI: pciehp: Retrieve link speed after link is trained

2011-11-07T16:07:34+00:00

During hot plug, board_added will call pciehp_power_on_slot().
But link speed is updated in pciehp_power_on_slot().

We should not update link speed there, because that is too early.

So move the link speed update to pciehp_check_link_status() after making
sure the link has been trained.

-v2: fix compile warning that Kenji found.

Signed-off-by: Yinghai Lu 
Reviewed-by: Kenji Kaneshige 
Tested-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

pci: add module.h to files implicitly relying on its presence.

2011-10-31T23:31:23+00:00

These were getting module.h implicitly from device.h but we want
to clean that up, so we fix it here to avoid things like:

pci/slot.c: In function ‘pci_hp_create_module_link’:
pci/slot.c:383: error: ‘module_kset’ undeclared (first use in this function)

Similarly, rpadlpar_core.c is modular, so add module.h to its includes.

Signed-off-by: Paul Gortmaker

pci: Fix files needing export.h for EXPORT_SYMBOL/THIS_MODULE

2011-10-31T23:31:22+00:00

They were implicitly getting it from device.h --> module.h but
we want to clean that up.  So add the minimal header for these
macros.

Signed-off-by: Paul Gortmaker

PCI / ACPI: Make acpiphp ignore root bridges using PCIe native hotplug

2011-10-31T17:17:43+00:00

If the kernel has requested control of the PCIe native hotplug
feature for a given root complex, the acpiphp driver should not try
to handle that root complex and it should leave it to pciehp.
Failing to do so causes problems to happen if acpiphp is loaded
before pciehp on such systems.

To address this issue make find_root_bridges() ignore PCIe root
complexes with PCIe native hotplug enabled and make add_bridge()
return error code if PCIe native hotplug is enabled for the given
root port.  This causes acpiphp to refuse to load if PCIe native
hotplug is enabled for all complexes and to refuse binding to
the root complexes with PCIe native hotplug is enabled.

Acked-by: Kenji Kaneshige 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Jesse Barnes