Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH -v4 2/2] PCIe: Add PCIe runtime D3cold support | Date | Wed, 30 May 2012 23:49:30 +0200 |
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On Tuesday, May 22, 2012, Rafael J. Wysocki wrote: > On Friday, May 18, 2012, Huang Ying wrote: > > This patch adds runtime D3cold support to PCIe bus. D3cold is the > > deepest power saving state for PCIe devices. Where the main PCIe link > > will be powered off totally, so before the PCIe main link is powered > > on again, you can not access the device, even the configuration space, > > which is still accessible in D3hot. Because the main PCIe link is not > > available, the PCI PM registers can not be used to put device into/out > > of D3cold state, that will be done by platform logic such as ACPI > > _PR3. > > > > To support remote wake up in D3cold, aux power is supplied, and a > > side-band pin: WAKE# is used to notify remote wake up event, the pin > > is usually connected to platform logic such as ACPI GPE. This is > > quite different with other power saving states, where remote wake up > > is notified via PME message through the PCIe main link. > > > > PCIe devices in plug-in slot usually has no direct platform logic, for > > example, there is usually no ACPI _PR3 for them. The D3cold support > > for these devices can be done via the PCIe port connected to it. When > > power on/off the PCIe port, the corresponding PCIe devices are powered > > on/off too. And the remote wake up event from PCIe device will be > > notified to the corresponding PCIe port. > > > > The PCI subsystem D3cold support and corresponding ACPI platform > > support is implemented in the patch. Including the support for PCIe > > devices in plug-in slot. > > > > For more information about PCIe D3cold and corresponding ACPI support, > > please refer to: > > > > - PCI Express Base Specification Revision 2.0 > > - Advanced Configuration and Power Interface Specification Revision 5.0 > > > > Originally-by: Zheng Yan <zheng.z.yan@intel.com> > > Signed-off-by: Huang Ying <ying.huang@intel.com> > > Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
On a second thought ...
> > --- > > drivers/pci/pci-acpi.c | 23 +++++++- > > drivers/pci/pci-driver.c | 3 + > > drivers/pci/pci-sysfs.c | 29 ++++++++++ > > drivers/pci/pci.c | 110 +++++++++++++++++++++++++++++++++++++---- > > drivers/pci/pci.h | 1 > > drivers/pci/pcie/portdrv_pci.c | 44 ++++++++++++++-- > > include/linux/pci.h | 16 ++++- > > 7 files changed, 205 insertions(+), 21 deletions(-) > > > > --- a/drivers/pci/pci-acpi.c > > +++ b/drivers/pci/pci-acpi.c > > @@ -48,6 +48,12 @@ static void pci_acpi_wake_dev(acpi_handl > > if (event != ACPI_NOTIFY_DEVICE_WAKE || !pci_dev) > > return; > > > > + if (pci_dev->current_state == PCI_D3cold) { > > + pci_wakeup_event(pci_dev); > > + pm_runtime_resume(&pci_dev->dev); > > + return; > > + } > > + > > if (!pci_dev->pm_cap || !pci_dev->pme_support > > || pci_check_pme_status(pci_dev)) { > > if (pci_dev->pme_poll) > > @@ -187,10 +193,13 @@ acpi_status pci_acpi_remove_pm_notifier( > > > > static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev) > > { > > - int acpi_state; > > + int acpi_state, d_max; > > > > - acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, > > - ACPI_STATE_D3);
I wonder what tree this patch is against? The code above doesn't seem to be present in the current mainline.
Thanks, Rafael
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