Messages in this thread | | | Subject | RE: [PATCH]PCIE ASPM support - takes 3 | Date | Fri, 25 Jan 2008 16:01:32 +0800 | From | "Li, Shaohua" <> |
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> > >Hi! > >> v3->v2, fixed the issues Matthew Wilcox raised. >> >> 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. > >How big is the latency? 1msec? 10msec? 100usec? Haven't accurate number, but in one device, it declaims L0s latency is < 128ns, L1 latency is < 64us.
Thanks, Shaohua
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