| Message ID | 20230619150408.8468-1-manivannan.sadhasivam@linaro.org |
|---|---|
| Headers | show |
| Series | PCI: qcom: Do not advertise hotplug capability | expand |
On Mon, 19 Jun 2023 20:33:59 +0530, Manivannan Sadhasivam wrote: > The SoCs making use of Qualcomm PCIe controllers do not support the PCIe 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) > > [...] Applied to controller/qcom, thanks! [1/9] PCI: qcom: Disable write access to read only registers for IP v2.3.3 https://git.kernel.org/pci/pci/c/a33d700e8eea [2/9] PCI: qcom: Use DWC helpers for modifying the read-only DBI registers https://git.kernel.org/pci/pci/c/60f0072d7fb7 [3/9] PCI: qcom: Disable write access to read only registers for IP v2.9.0 https://git.kernel.org/pci/pci/c/200b8f85f202 [4/9] PCI: qcom: Do not advertise hotplug capability for IPs v2.7.0 and v1.9.0 https://git.kernel.org/pci/pci/c/a54db86ddc15 [5/9] PCI: qcom: Do not advertise hotplug capability for IPs v2.3.3 and v2.9.0 https://git.kernel.org/pci/pci/c/11bce06b21a0 [6/9] PCI: qcom: Do not advertise hotplug capability for IP v2.3.2 https://git.kernel.org/pci/pci/c/25966e78d303 [7/9] PCI: qcom: Use post init sequence of IP v2.3.2 for v2.4.0 https://git.kernel.org/pci/pci/c/e35d13a5ff37 [8/9] PCI: qcom: Do not advertise hotplug capability for IP v1.0.0 https://git.kernel.org/pci/pci/c/fa2dc2528684 [9/9] PCI: qcom: Do not advertise hotplug capability for IP v2.1.0 https://git.kernel.org/pci/pci/c/1fdecc5bc8e8 Thanks, Lorenzo
Hi, The SoCs making use of Qualcomm PCIe controllers do not support the PCIe 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, this series clears the HPC bit in PCI_EXP_SLTCAP register as a part of the post init sequence for all IP versions to not advertise the hotplug capability for the controller. Testing ======= This series has been tested on DB845c (SDM845 SoC) and Lenovo Thinkpad X13s (SC8280XP SoC). Thanks, Mani Changes in v4: * Splitted patch 1/8 into two * Rebased on top of pci/next Changes in v3: * Dropped double signed-off tags * Dropped Dmitry's gmail reviewed tag as per his request * Mentioned the newline change in commit log of patch 2/8 Changes in v2: * Collected tags * Moved the HPC clearing to a separate function and reused across different configs Manivannan Sadhasivam (9): PCI: qcom: Disable write access to read only registers for IP v2.3.3 PCI: qcom: Use DWC helpers for modifying the read-only DBI registers PCI: qcom: Disable write access to read only registers for IP v2.9.0 PCI: qcom: Do not advertise hotplug capability for IPs v2.7.0 and v1.9.0 PCI: qcom: Do not advertise hotplug capability for IPs v2.3.3 and v2.9.0 PCI: qcom: Do not advertise hotplug capability for IP v2.3.2 PCI: qcom: Use post init sequence of IP v2.3.2 for v2.4.0 PCI: qcom: Do not advertise hotplug capability for IP v1.0.0 PCI: qcom: Do not advertise hotplug capability for IP v2.1.0 drivers/pci/controller/dwc/pcie-qcom.c | 73 ++++++++++++++------------ 1 file changed, 38 insertions(+), 35 deletions(-)