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This patch adds runtime D3cold support and corresponding ACPI platform support. This patch only enables runtime D3cold support; it does not enable D3cold support during system suspend/hibernate. D3cold is the deepest power saving state for a PCIe device, where its main power is removed. While it is in D3cold, you can't access the device at all, not even its configuration space (which is still accessible in D3hot). Therefore the PCI PM registers can not be used to transition into/out of the D3cold state; that must be done by platform logic such as ACPI _PR3. To support wakeup from D3cold, a system may provide auxiliary power, which allows a device to request wakeup using a Beacon or the sideband WAKE# signal. WAKE# is usually connected to platform logic such as ACPI GPE. This is quite different from other power saving states, where devices request wakeup via a PME message on the PCIe link. Some devices, such as those in plug-in slots, have no direct platform logic. For example, there is usually no ACPI _PR3 for them. D3cold support for these devices can be done via the PCIe Downstream Port leading to the device. When the PCIe port is powered on/off, the device is powered on/off too. Wakeup events from the device will be notified to the corresponding PCIe port. 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 [bhelgaas: changelog] Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl> Originally-by: Zheng Yan <zheng.z.yan@intel.com> Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> |
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| .. | ||
| aer | ||
| aspm.c | ||
| Kconfig | ||
| Makefile | ||
| pme.c | ||
| portdrv_acpi.c | ||
| portdrv_bus.c | ||
| portdrv_core.c | ||
| portdrv_pci.c | ||
| portdrv.h | ||