Messages in this thread | | | Date | Wed, 14 Sep 2022 07:17:00 +0530 | Subject | Re: [PATCH v6 0/5] PCI: qcom: Add system suspend & resume support | From | Krishna Chaitanya Chundru <> |
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On 9/12/2022 11:07 PM, Manivannan Sadhasivam wrote: > On Fri, Sep 09, 2022 at 02:14:39PM +0530, Krishna chaitanya chundru wrote: >> Add suspend and resume syscore ops. >> >> When system suspends, and if the link is in L1ss, disable the clocks >> and power down the phy so that system enters into low power state by >> parking link in L1ss to save the maximum power. And when the system >> resumes, enable the clocks back and power on phy if they are disabled >> in the suspend path. >> > You need to mention that you are only turning off the PCIe controller > clocks and PHY is still powered by a separate domain (MX) so the link > statys intact. sure I will update the commit in next series. >> we are doing this only when link is in l1ss but not in L2/L3 as >> nowhere we are forcing link to L2/L3 by sending PME turn off. >> >> is_suspended flag indicates if the clocks are disabled in the suspend >> path or not. >> >> There is access to Ep PCIe space to mask MSI/MSIX after pm suspend ops >> (getting hit by affinity changes while making CPUs offline during suspend, >> this will happen after devices are suspended (all phases of suspend ops)). >> When registered with pm ops there is a crash due to un-clocked access, >> as in the pm suspend op clocks are disabled. So, registering with syscore >> ops which will called after making CPUs offline. >> >> Make GDSC always on to ensure controller and its dependent clocks >> won't go down during system suspend. >> > Where is the changelog? You seem to have added PHY and CLK patches to > this series. You need to comment on that. > > Thanks, > Mani I will update that in next patch. >> Krishna chaitanya chundru (5): >> PCI: qcom: Add system suspend and resume support >> PCI: qcom: Add retry logic for link to be stable in L1ss >> phy: core: Add support for phy power down & power up >> phy: qcom: Add power down/up callbacks to pcie phy >> clk: qcom: Alwaya on pcie gdsc >> >> drivers/clk/qcom/gcc-sc7280.c | 2 +- >> drivers/pci/controller/dwc/pcie-qcom.c | 156 ++++++++++++++++++++++++++++++- >> drivers/phy/phy-core.c | 30 ++++++ >> drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 50 ++++++++++ >> include/linux/phy/phy.h | 20 ++++ >> 5 files changed, 256 insertions(+), 2 deletions(-) >> >> -- >> 2.7.4 >>
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