| Message ID | 20181107003250.5832-1-elder@linaro.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | net: introduce Qualcomm IPA driver | expand |
On Wed, Nov 7, 2018 at 1:33 AM Alex Elder <elder@linaro.org> wrote: > The code has undergone considerable rework to prepare it for > incorporation into upstream Linux. Parts of it bear little > resemblance to the original driver. Still, some work remains > to be done. The current code and its design had a preliminary > review, and some changes to the data path implementation were > recommended. These have not yet been addressed: > - Use NAPI for all interfaces, not just RX (and WAN data) endpoints. > - Do more work in the NAPI poll function, including collecting > completed TX requests and posting buffers for RX. > - Do not use periodic NOP requests as a way to avoid TX interrupts. > - The NAPI context should be associated with the hardware interrupt > (it is now associated with something abstracted from the hardware). > - Use threaded interrupts, to avoid the need for using spinlocks and > atomic variables for synchronizing between workqueue and interrupt > context. > - Have runtime power management enable and disable IPA clock and > interconnects. > Many thanks to Arnd Bergmann, Ilias Apalodimas, and Bjorn Andersson > for their early feedback. Thanks for getting the current version out even with the long TODO list. I've had my first deeper look at some of the patches and found a few more things that likely require substantial rework. I also think there is still significant room for simplifying it further, and getting better performance out of it in the process. Also, despite the criticism in my patch review, I have to say you've done a great job at cutting out a lot of the things that were present in the past, it's good to see that you have come this far with the cleanup! Arnd
This series presents the driver for the Qualcomm IP Accelerator (IPA). The IPA is a hardware component present in some Qualcomm SoCs that allows network functions--such as routing, filtering, network address translation and aggregation--to be performed without active involvement of the main application processor (AP). Initially, these advanced features are not supported; the IPA driver simply provides a network interface that makes the modem's LTE network available to the AP. In addition, support is only provided for the IPA found in the Qualcomm SDM845 SoC. This code is derived from a driver developed internally by Qualcomm. A version of the original source can be seen here: https://source.codeaurora.org/quic/la/kernel/msm-4.9/tree in the "drivers/platform/msm/ipa" directory. Many were involved in developing this, but the following individuals deserve explicit acknowledgement for their substantial contributions: Abhishek Choubey Ady Abraham Chaitanya Pratapa David Arinzon Ghanim Fodi Gidon Studinski Ravi Gummadidala Shihuan Liu Skylar Chang The code has undergone considerable rework to prepare it for incorporation into upstream Linux. Parts of it bear little resemblance to the original driver. Still, some work remains to be done. The current code and its design had a preliminary review, and some changes to the data path implementation were recommended. These have not yet been addressed: - Use NAPI for all interfaces, not just RX (and WAN data) endpoints. - Do more work in the NAPI poll function, including collecting completed TX requests and posting buffers for RX. - Do not use periodic NOP requests as a way to avoid TX interrupts. - The NAPI context should be associated with the hardware interrupt (it is now associated with something abstracted from the hardware). - Use threaded interrupts, to avoid the need for using spinlocks and atomic variables for synchronizing between workqueue and interrupt context. - Have runtime power management enable and disable IPA clock and interconnects. Many thanks to Arnd Bergmann, Ilias Apalodimas, and Bjorn Andersson for their early feedback. While there clearly remains work to do on this, we felt that things are far enough along that it would be helpful to solicit broader input on the code. Major issues are best addressed as soon as possible, and even minor issues when identified help in setting priorities. This code is dependent on the following two sets of code, which have been posted for review but are not yet accepted upstream: - Interconnect framework: https://lkml.org/lkml/2018/8/31/444 - SDM845 interconnect provider driver: https://lkml.org/lkml/2018/8/24/25 In addition, it depends on four more bits of code that have not yet been posted for upstream review, but are expected to be available soon: - clk-rpmh support for IPA from David Dai <daidavid1@codeaurora.org> - SDM845 reserved memory from Bjorn Andersson <bjorn.andersson@linaro.org> - list_cut_end() from Alex Elder <elder@linaro.org> - FIELD_MAX() in "bitfield.h" from Alex Elder <elder@linaro.org> This code (including its dependencies) is available in buildable form here, based on kernel v4.19: remote: ssh://git@git.linaro.org/people/alex.elder/linux.git branch: qualcomm_ipa-v1 59562facd61a arm64: dts: sdm845: add IPA information -Alex Alex Elder (12): dt-bindings: soc: qcom: add IPA bindings soc: qcom: ipa: DMA helpers soc: qcom: ipa: generic software interface soc: qcom: ipa: immediate commands soc: qcom: ipa: IPA interrupts and the microcontroller soc: qcom: ipa: QMI modem communication soc: qcom: ipa: IPA register abstraction soc: qcom: ipa: utility functions soc: qcom: ipa: main IPA source file soc: qcom: ipa: data path soc: qcom: ipa: IPA rmnet interface soc: qcom: ipa: build and "ipa_i.h" .../devicetree/bindings/soc/qcom/qcom,ipa.txt | 136 ++ .../bindings/soc/qcom/qcom,rmnet-ipa.txt | 15 + drivers/net/ipa/Kconfig | 30 + drivers/net/ipa/Makefile | 7 + drivers/net/ipa/gsi.c | 1685 ++++++++++++++ drivers/net/ipa/gsi.h | 195 ++ drivers/net/ipa/gsi_reg.h | 563 +++++ drivers/net/ipa/ipa_dma.c | 61 + drivers/net/ipa/ipa_dma.h | 61 + drivers/net/ipa/ipa_dp.c | 1994 +++++++++++++++++ drivers/net/ipa/ipa_i.h | 573 +++++ drivers/net/ipa/ipa_interrupts.c | 307 +++ drivers/net/ipa/ipa_main.c | 1400 ++++++++++++ drivers/net/ipa/ipa_qmi.c | 406 ++++ drivers/net/ipa/ipa_qmi.h | 12 + drivers/net/ipa/ipa_qmi_msg.c | 587 +++++ drivers/net/ipa/ipa_qmi_msg.h | 233 ++ drivers/net/ipa/ipa_reg.c | 972 ++++++++ drivers/net/ipa/ipa_reg.h | 614 +++++ drivers/net/ipa/ipa_uc.c | 336 +++ drivers/net/ipa/ipa_utils.c | 1035 +++++++++ drivers/net/ipa/ipahal.c | 541 +++++ drivers/net/ipa/ipahal.h | 253 +++ drivers/net/ipa/msm_rmnet.h | 120 + drivers/net/ipa/rmnet_config.h | 31 + drivers/net/ipa/rmnet_ipa.c | 805 +++++++ 26 files changed, 12972 insertions(+) create mode 100644 Documentation/devicetree/bindings/soc/qcom/qcom,ipa.txt create mode 100644 Documentation/devicetree/bindings/soc/qcom/qcom,rmnet-ipa.txt create mode 100644 drivers/net/ipa/Kconfig create mode 100644 drivers/net/ipa/Makefile create mode 100644 drivers/net/ipa/gsi.c create mode 100644 drivers/net/ipa/gsi.h create mode 100644 drivers/net/ipa/gsi_reg.h create mode 100644 drivers/net/ipa/ipa_dma.c create mode 100644 drivers/net/ipa/ipa_dma.h create mode 100644 drivers/net/ipa/ipa_dp.c create mode 100644 drivers/net/ipa/ipa_i.h create mode 100644 drivers/net/ipa/ipa_interrupts.c create mode 100644 drivers/net/ipa/ipa_main.c create mode 100644 drivers/net/ipa/ipa_qmi.c create mode 100644 drivers/net/ipa/ipa_qmi.h create mode 100644 drivers/net/ipa/ipa_qmi_msg.c create mode 100644 drivers/net/ipa/ipa_qmi_msg.h create mode 100644 drivers/net/ipa/ipa_reg.c create mode 100644 drivers/net/ipa/ipa_reg.h create mode 100644 drivers/net/ipa/ipa_uc.c create mode 100644 drivers/net/ipa/ipa_utils.c create mode 100644 drivers/net/ipa/ipahal.c create mode 100644 drivers/net/ipa/ipahal.h create mode 100644 drivers/net/ipa/msm_rmnet.h create mode 100644 drivers/net/ipa/rmnet_config.h create mode 100644 drivers/net/ipa/rmnet_ipa.c