Re: [PATCH v2 00/17] net: introduce Qualcomm IPA driver
From: Dan Williams <hidden>
Date: 2019-05-31 14:59:15
Also in:
linux-arm-kernel, linux-arm-msm, linux-devicetree, lkml
On Thu, 2019-05-30 at 22:53 -0500, Alex Elder wrote:
This series presents the driver for the Qualcomm IP Accelerator (IPA). This is version 2 of the series. This version has addressed almost all of the feedback received in the first version: https://lore.kernel.org/lkml/20190512012508.10608-1-elder@linaro.org/ (local) More detail is included in the individual patches, but here is a high-level summary of what's changed since then: - Two spinlocks have been removed. - The code for enabling and disabling endpoint interrupts has been simplified considerably, and the spinlock is no longer required - A spinlock used when updating ring buffer pointers is no longer needed. Integers indexing the ring are used instead (and they don't even have to be atomic). - One spinlock remains to protect list updates, but it is always acquired using spin_lock_bh() (no more irqsave). - Information about the queueing and completion of messages is now supplied to the network stack in batches rather than one at a time. - I/O completion handling has been simplified, with the IRQ handler now consisting mainly of disabling the interrupt and calling napi_schedule(). - Some comments have been updated and improved througout. What follows is the introduction supplied with v1 of the series. ----- The IPA is a component present in some Qualcomm SoCs that allows network functions such as aggregation, filtering, routing, and NAT to be performed without active involvement of the main application processor (AP). Initially, these advanced features are disabled; the IPA driver simply provides a network interface that makes the modem's LTE network available to the AP. In addition, only support for the IPA found in the Qualcomm SDM845 SoC is provided.
My question from the Nov 2018 IPA rmnet driver still stands; how does this relate to net/ethernet/qualcomm/rmnet/ if at all? And if this is really just a netdev talking to the IPA itself and unrelated to net/ethernet/qualcomm/rmnet, let's call it "ipa%d" and stop cargo- culting rmnet around just because it happens to be a net driver for a QC SoC. Is the firmware that the driver loads already in linux-firmware or going to be there soon? How does the driver support multiple PDNs (eg PDP or EPS contexts) that are enabled through the control plane via QMI messages? I couldn't quite find that out. Thanks, Dan
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 A version of this code was posted in November 2018 as an RFC. https://lore.kernel.org/lkml/20181107003250.5832-1-elder@linaro.org/ (local) All feedback received was addressed. The code has undergone considerable further rework since that time, and most of the "future work" described then has now been completed. This code is available in buildable form here, based on kernel v5.2-rc1: remote: ssh://git@git.linaro.org/people/alex.elder/linux.git branch: ipa-v2_kernel-v5.2-rc2 75adf2ac1266 arm64: defconfig: enable build of IPA code The branch depends on a commit now found in in net-next. It has been cherry-picked, and (in this branch) has this commit ID: 13c627b5a078 net: qualcomm: rmnet: Move common struct definitions to include by -Alex Alex Elder (17): bitfield.h: add FIELD_MAX() and field_max() dt-bindings: soc: qcom: add IPA bindings soc: qcom: ipa: main code soc: qcom: ipa: configuration data soc: qcom: ipa: clocking, interrupts, and memory soc: qcom: ipa: GSI headers soc: qcom: ipa: the generic software interface soc: qcom: ipa: GSI transactions soc: qcom: ipa: IPA interface to GSI soc: qcom: ipa: IPA endpoints soc: qcom: ipa: immediate commands soc: qcom: ipa: IPA network device and microcontroller soc: qcom: ipa: AP/modem communications soc: qcom: ipa: support build of IPA code MAINTAINERS: add entry for the Qualcomm IPA driver arm64: dts: sdm845: add IPA information arm64: defconfig: enable build of IPA code .../devicetree/bindings/net/qcom,ipa.yaml | 180 ++ MAINTAINERS | 6 + arch/arm64/boot/dts/qcom/sdm845.dtsi | 51 + arch/arm64/configs/defconfig | 1 + drivers/net/Kconfig | 2 + drivers/net/Makefile | 1 + drivers/net/ipa/Kconfig | 16 + drivers/net/ipa/Makefile | 7 + drivers/net/ipa/gsi.c | 1635 +++++++++++++++++ drivers/net/ipa/gsi.h | 246 +++ drivers/net/ipa/gsi_private.h | 148 ++ drivers/net/ipa/gsi_reg.h | 376 ++++ drivers/net/ipa/gsi_trans.c | 624 +++++++ drivers/net/ipa/gsi_trans.h | 116 ++ drivers/net/ipa/ipa.h | 131 ++ drivers/net/ipa/ipa_clock.c | 297 +++ drivers/net/ipa/ipa_clock.h | 52 + drivers/net/ipa/ipa_cmd.c | 377 ++++ drivers/net/ipa/ipa_cmd.h | 116 ++ drivers/net/ipa/ipa_data-sdm845.c | 245 +++ drivers/net/ipa/ipa_data.h | 267 +++ drivers/net/ipa/ipa_endpoint.c | 1283 +++++++++++++ drivers/net/ipa/ipa_endpoint.h | 97 + drivers/net/ipa/ipa_gsi.c | 48 + drivers/net/ipa/ipa_gsi.h | 49 + drivers/net/ipa/ipa_interrupt.c | 279 +++ drivers/net/ipa/ipa_interrupt.h | 53 + drivers/net/ipa/ipa_main.c | 921 ++++++++++ drivers/net/ipa/ipa_mem.c | 234 +++ drivers/net/ipa/ipa_mem.h | 83 + drivers/net/ipa/ipa_netdev.c | 251 +++ drivers/net/ipa/ipa_netdev.h | 24 + drivers/net/ipa/ipa_qmi.c | 402 ++++ drivers/net/ipa/ipa_qmi.h | 35 + drivers/net/ipa/ipa_qmi_msg.c | 583 ++++++ drivers/net/ipa/ipa_qmi_msg.h | 238 +++ drivers/net/ipa/ipa_reg.h | 279 +++ drivers/net/ipa/ipa_smp2p.c | 304 +++ drivers/net/ipa/ipa_smp2p.h | 47 + drivers/net/ipa/ipa_uc.c | 208 +++ drivers/net/ipa/ipa_uc.h | 32 + include/linux/bitfield.h | 14 + 42 files changed, 10358 insertions(+) create mode 100644 Documentation/devicetree/bindings/net/qcom,ipa.yaml 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_private.h create mode 100644 drivers/net/ipa/gsi_reg.h create mode 100644 drivers/net/ipa/gsi_trans.c create mode 100644 drivers/net/ipa/gsi_trans.h create mode 100644 drivers/net/ipa/ipa.h create mode 100644 drivers/net/ipa/ipa_clock.c create mode 100644 drivers/net/ipa/ipa_clock.h create mode 100644 drivers/net/ipa/ipa_cmd.c create mode 100644 drivers/net/ipa/ipa_cmd.h create mode 100644 drivers/net/ipa/ipa_data-sdm845.c create mode 100644 drivers/net/ipa/ipa_data.h create mode 100644 drivers/net/ipa/ipa_endpoint.c create mode 100644 drivers/net/ipa/ipa_endpoint.h create mode 100644 drivers/net/ipa/ipa_gsi.c create mode 100644 drivers/net/ipa/ipa_gsi.h create mode 100644 drivers/net/ipa/ipa_interrupt.c create mode 100644 drivers/net/ipa/ipa_interrupt.h create mode 100644 drivers/net/ipa/ipa_main.c create mode 100644 drivers/net/ipa/ipa_mem.c create mode 100644 drivers/net/ipa/ipa_mem.h create mode 100644 drivers/net/ipa/ipa_netdev.c create mode 100644 drivers/net/ipa/ipa_netdev.h 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.h create mode 100644 drivers/net/ipa/ipa_smp2p.c create mode 100644 drivers/net/ipa/ipa_smp2p.h create mode 100644 drivers/net/ipa/ipa_uc.c create mode 100644 drivers/net/ipa/ipa_uc.h