APSS brings Q6 out of reset and then Q6 brings WCSS block (wifi radio's) out of reset. --------------- --> |WiFi 2G radio| | -------------- | -------- ------- | | APSS | ---> |QDSP6| -----| --------- ------- | | | | -------------- --> |WiFi 5G radio| -------------- Problem here is if any radio crashes, subsequently other radio also should crash because Q6 crashed. Let's say 2G radio crashed, Q6 should pass this info to APSS. Only Q6 processor interrupts registered with APSS. Obviously Q6 should crash and raise fatal interrupt to APSS. Due to this 5G radio also crashed. But no issue in 5G radio, because of 2G radio crash 5G radio also impacted. In multi pd model, this problem is resolved. Here WCSS functionality (WiFi radio's) moved out from Q6 root pd to a separate user pd. Due to this, radio's independently pass their status info to APPS with out crashing Q6. So other radio's won't be impacted. Pd means protection domain. It's similar to process in Linux. Here QDSP6 processor runs each wifi radio functionality on a separate process. One process can't access other process resources, so this is termed as PD i.e protection domain. --------- |WiFi | --> |2G radio| | --------- ------ Start Q6 ------- | | | ------------------> | | | | | Start WCSS PD1 (2G) | | | |APSS| ----------------------->|QDSP6|-----| | | Start WCSS PD1 (5G) | | | | ----------------------->| |-----| ------ ------- | | | ----------- |-->|WiFi | |5G radio | ----------- According to linux terminology, here consider Q6 as root i.e it provide all services, WCSS (wifi radio's) as user i.e it uses services provided by root. Since Q6 root & WCSS user pd's able to communicate with APSS individually, multipd remoteproc driver registers each PD with rproc framework. Here clients (Wifi host drivers) intrested on WCSS PD rproc, so multipd driver start's root pd in the context of WCSS user pd rproc start. Similarly on down path, root pd will be stopped after wcss user pd stopped. Here WCSS(user) PD is dependent on Q6(root) PD, so first q6 pd should be up before wcss pd. After wcss pd goes down, q6 pd should be turned off. rproc->ops->start(userpd_rproc) { /* Boot root pd rproc */ rproc_boot(upd_dev->parent); --- /* user pd rproc start sequence */ --- --- } With this way we ensure that root pd brought up before userpd. rproc->ops->stop(userpd_rproc) { --- --- /* user pd rproc stop sequence */ --- --- /* Shutdown root pd rproc */ rproc_shutdown(upd_dev->parent); } After userpd rproc stops, root pd rproc will be stopped. IPQ5018, IPQ9574 supports multipd remoteproc driver. DTS patch [13/13] is based on below series https://lore.kernel.org/linux-arm-msm/20230519090219.15925-1-quic_devipriy@xxxxxxxxxxx/ [V2] - This patch is depends on the below series https://lore.kernel.org/linux-arm-msm/20230519090219.15925-1-quic_devipriy@xxxxxxxxxxx/ https://lore.kernel.org/linux-arm-msm/20230519125409.497439-1-quic_srichara@xxxxxxxxxxx/ - Fixed all comments and rebased for TOT. - Strip off SCM code changes from https://lore.kernel.org/linux-arm-msm/1678164097-13247-9-git-send-email-quic_mmanikan@xxxxxxxxxxx/ and made new patchset [08/13] - Strip off qcom_q6v5 changes from https://lore.kernel.org/linux-arm-msm/1678164097-13247-9-git-send-email-quic_mmanikan@xxxxxxxxxxx/ and made new patchset [09/13] - since clocks handled by QDSP6 firmware Dropped https://lore.kernel.org/linux-arm-msm/1678164097-13247-6-git-send-email-quic_mmanikan@xxxxxxxxxxx/, https://lore.kernel.org/linux-arm-msm/1678164097-13247-7-git-send-email-quic_mmanikan@xxxxxxxxxxx/. Added [04/13], [05/13], [06/13], [07/13] patches. Manikanta Mylavarapu (13): dt-bindings: remoteproc: qcom: Add support for multipd model dt-bindings: mailbox: qcom: Add IPQ5018 APCS compatible dt-bindings: arm: qcom: Document the Qualcomm rdp432-c1 board dt-bindings: clock: qcom: gcc-ipq5018: remove q6 clocks macros dt-bindings: clock: qcom: gcc-ipq9574: remove q6 bring up clock macros clk: qcom: ipq5018: remove q6 bring up clocks clk: qcom: ipq9574: remove q6 bring up clocks firmware: qcom_scm: ipq5018: Add WCSS AHB pd support remoteproc: qcom: q6v5: Add multipd interrupts support remoteproc: qcom: Add Hexagon based multipd rproc driver arm64: dtsi: qcom: ipq5018: enable nodes required for multipd arm64: dts: qcom: ipq5018: Add RDP432-c1 board support arm64: dtsi: qcom: ipq9574: Add nodes to bring up multipd .../devicetree/bindings/arm/qcom.yaml | 1 + .../mailbox/qcom,apcs-kpss-global.yaml | 1 + .../bindings/remoteproc/qcom,multipd-pil.yaml | 265 +++++++ arch/arm64/boot/dts/qcom/Makefile | 1 + .../arm64/boot/dts/qcom/ipq5018-rdp432-c1.dts | 49 ++ arch/arm64/boot/dts/qcom/ipq5018.dtsi | 140 ++++ arch/arm64/boot/dts/qcom/ipq9574.dtsi | 118 +++ drivers/clk/qcom/gcc-ipq5018.c | 414 ----------- drivers/clk/qcom/gcc-ipq9574.c | 326 --------- drivers/firmware/qcom_scm.c | 114 +++ drivers/firmware/qcom_scm.h | 6 + drivers/remoteproc/Kconfig | 20 + drivers/remoteproc/Makefile | 1 + drivers/remoteproc/qcom_common.h | 9 + drivers/remoteproc/qcom_q6v5.c | 37 +- drivers/remoteproc/qcom_q6v5.h | 11 + drivers/remoteproc/qcom_q6v5_mpd.c | 677 ++++++++++++++++++ drivers/soc/qcom/mdt_loader.c | 332 +++++++++ include/dt-bindings/clock/qcom,gcc-ipq5018.h | 21 - include/dt-bindings/clock/qcom,ipq9574-gcc.h | 18 - include/linux/firmware/qcom/qcom_scm.h | 3 + include/linux/soc/qcom/mdt_loader.h | 19 + 22 files changed, 1801 insertions(+), 782 deletions(-) create mode 100644 Documentation/devicetree/bindings/remoteproc/qcom,multipd-pil.yaml create mode 100644 arch/arm64/boot/dts/qcom/ipq5018-rdp432-c1.dts create mode 100644 drivers/remoteproc/qcom_q6v5_mpd.c base-commit: dbd91ef4e91c1ce3a24429f5fb3876b7a0306733 -- 2.17.1