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[v4,5/9] PCI: qcom: Do not advertise hotplug capability for IPs v2.3.3 and v2.9.0

Message ID 20230619150408.8468-6-manivannan.sadhasivam@linaro.org (mailing list archive)
State Accepted
Delegated to: Lorenzo Pieralisi
Headers show
Series PCI: qcom: Do not advertise hotplug capability | expand

Commit Message

Manivannan Sadhasivam June 19, 2023, 3:04 p.m. UTC 
SoCs making use of Qcom PCIe controller IPs v2.3.3 and v2.9.0 do not
support hotplug functionality. But the hotplug capability bit is set by
default in the hardware. This causes the kernel PCI core to register
hotplug service for the controller and send hotplug commands to it. But
those commands will timeout generating messages as below during boot
and suspend/resume.

[    5.782159] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2020 msec ago)
[    5.810161] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2048 msec ago)
[    7.838162] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x07c0 (issued 2020 msec ago)
[    7.870159] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x07c0 (issued 2052 msec ago)

This not only spams the console output but also induces a delay of a
couple of seconds. To fix this issue, let's not set the HPC bit in
PCI_EXP_SLTCAP register as a part of the post init sequence to not
advertise the hotplug capability for the controller.

Tested-by: Sricharan Ramabadhran <quic_srichara@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-qcom.c | 1 -
 1 file changed, 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 8f448156eccc..64b6a8c6a99d 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -140,7 +140,6 @@ 
 						PCI_EXP_SLTCAP_AIP | \
 						PCI_EXP_SLTCAP_PIP | \
 						PCI_EXP_SLTCAP_HPS | \
-						PCI_EXP_SLTCAP_HPC | \
 						PCI_EXP_SLTCAP_EIP | \
 						PCIE_CAP_SLOT_POWER_LIMIT_VAL | \
 						PCIE_CAP_SLOT_POWER_LIMIT_SCALE)