| Message ID | 20200514145927.17555-1-kishon@ti.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Implement NTB Controller using multiple PCI EP | expand |
On Thu, May 14, 2020 at 8:59 AM Kishon Vijay Abraham I <kishon@ti.com> wrote: > > This series is about implementing SW defined NTB using > multiple endpoint instances. This series has been tested using > 2 endpoint instances in J7 connected to two DRA7 boards. However there > is nothing platform specific for the NTB functionality. > > This was presented in Linux Plumbers Conference. The presentation > can be found @ [1] I'd like to know why putting this into DT is better than configfs. Does it solve some problem? Doing things in userspace is so much easier and more flexible than modifying and updating a DT. I don't really think the PCI endpoint stuff is mature enough to be putting into DT either. Rob
Hi Rob, On 5/22/2020 9:41 PM, Rob Herring wrote: > On Thu, May 14, 2020 at 8:59 AM Kishon Vijay Abraham I <kishon@ti.com> wrote: >> >> This series is about implementing SW defined NTB using >> multiple endpoint instances. This series has been tested using >> 2 endpoint instances in J7 connected to two DRA7 boards. However there >> is nothing platform specific for the NTB functionality. >> >> This was presented in Linux Plumbers Conference. The presentation >> can be found @ [1] > > I'd like to know why putting this into DT is better than configfs. > Does it solve some problem? Doing things in userspace is so much > easier and more flexible than modifying and updating a DT. It's a lot cleaner to have an endpoint function bound to two different endpoint controller using device tree than configfs. + epf_bus { + compatible = "pci-epf-bus"; + + func@0 { + compatible = "pci-epf-ntb"; + epcs = <&pcie0_ep>, <&pcie1_ep>; + epc-names = "primary", "secondary"; + reg = <0>; + epf,vendor-id = /bits/ 16 <0x104c>; + epf,device-id = /bits/ 16 <0xb00d>; + num-mws = <4>; + mws-size = <0x0 0x100000>, <0x0 0x100000>, <0x0 0x100000>, <0x0 0x100000>; + }; For device tree, just using phandles is enough and the driver can easily parse DT to get EPCs bound to the endpoint function + epcs = <&pcie0_ep>, <&pcie1_ep>; + epc-names = "primary", "secondary"; This would be ln -s functions/pci-epf-ntb/func1 controllers/2900000.pcie-ep/ ln -s functions/pci-epf-ntb/func1 controllers/2910000.pcie-ep/ pci_epc_epf_link() should then maintain the order of EPC bound to EPF and designate one as PRIMARY_INTERFACE and the second as SECONDARY_INTERFACE. pci_epf_bind() should be made to behave differently for NTB case. While the standard properties (like vendorid, deviceid) has configfs entries, additional logic would be required for adding function specific fields like num-mws and mws-size above. While all this support could be added in configfs, it looks simpler to represent then in DT. > > I don't really think the PCI endpoint stuff is mature enough to be > putting into DT either. I think this will anyways come when we have to export real HW peripherals to the remote HOST using EP controller. Thanks Kishon
This series is about implementing SW defined NTB using multiple endpoint instances. This series has been tested using 2 endpoint instances in J7 connected to two DRA7 boards. However there is nothing platform specific for the NTB functionality. This was presented in Linux Plumbers Conference. The presentation can be found @ [1] RFC patch series can be found @ [2] This series has been validated after applying [3] and [4] Changes from RFC: 1) Converted the DT binding patches to YAML schema and merged the DT binding patches together 2) NTB documentation is converted to .rst 3) One HOST can now interrupt the other HOST using MSI-X interrupts 4) Added support for teardown of memory window and doorbell configuration 5) Add support to provide support 64-bit memory window size from DT [1] -> https://www.linuxplumbersconf.org/event/4/contributions/395/attachments/284/481/Implementing_NTB_Controller_Using_PCIe_Endpoint_-_final.pdf [2] -> http://lore.kernel.org/r/20190926112933.8922-1-kishon@ti.com [3] -> http://lore.kernel.org/r/20200508130646.23939-1-kishon@ti.com [4] -> http://lore.kernel.org/r/20200506151429.12255-1-kishon@ti.com Kishon Vijay Abraham I (19): dt-bindings: PCI: Endpoint: Add DT bindings for PCI EPF NTB Device Documentation: PCI: Add specification for the *PCI NTB* function device PCI: endpoint: Add API to get reference to EPC from device-tree PCI: endpoint: Add API to create EPF device from device tree PCI: endpoint: Add "pci-epf-bus" driver PCI: endpoint: Make *_get_first_free_bar() take into account 64 bit BAR PCI: endpoint: Add helper API to get the 'next' unreserved BAR PCI: endpoint: Make *_free_bar() to return error codes on failure PCI: endpoint: Remove unused pci_epf_match_device() PCI: endpoint: Make pci_epf_driver ops optional PCI: endpoint: Add helper API to populate header with values from DT PCI: endpoint: Add support to associate secondary EPC with EPF PCI: endpoint: Add pci_epc_ops to map MSI irq PCI: cadence: Implement ->msi_map_irq() ops PCI: endpoint: Add EP function driver to provide NTB functionality PCI: Add TI J721E device to pci ids NTB: Add support for EPF PCI-Express Non-Transparent Bridge NTB: tool: Enable the NTB/PCIe link on the local or remote side of bridge NTB: ntb_perf/ntb_tool: Use PCI device for dma_alloc_coherent() Documentation/PCI/endpoint/index.rst | 1 + Documentation/PCI/endpoint/pci-test-ntb.rst | 344 +++ .../bindings/pci/endpoint/pci-epf-bus.yaml | 42 + .../bindings/pci/endpoint/pci-epf-device.yaml | 69 + .../bindings/pci/endpoint/pci-epf-ntb.yaml | 68 + drivers/misc/pci_endpoint_test.c | 1 - drivers/ntb/hw/Kconfig | 1 + drivers/ntb/hw/Makefile | 1 + drivers/ntb/hw/epf/Kconfig | 5 + drivers/ntb/hw/epf/Makefile | 1 + drivers/ntb/hw/epf/ntb_hw_epf.c | 752 ++++++ drivers/ntb/test/ntb_perf.c | 3 +- drivers/ntb/test/ntb_tool.c | 4 +- .../pci/controller/cadence/pcie-cadence-ep.c | 50 + drivers/pci/endpoint/Makefile | 3 +- drivers/pci/endpoint/functions/Kconfig | 12 + drivers/pci/endpoint/functions/Makefile | 1 + drivers/pci/endpoint/functions/pci-epf-ntb.c | 2038 +++++++++++++++++ drivers/pci/endpoint/functions/pci-epf-test.c | 13 +- drivers/pci/endpoint/pci-ep-cfs.c | 6 +- drivers/pci/endpoint/pci-epc-core.c | 216 +- drivers/pci/endpoint/pci-epf-bus.c | 54 + drivers/pci/endpoint/pci-epf-core.c | 137 +- include/linux/pci-epc.h | 43 +- include/linux/pci-epf.h | 26 +- include/linux/pci_ids.h | 1 + 26 files changed, 3823 insertions(+), 69 deletions(-) create mode 100644 Documentation/PCI/endpoint/pci-test-ntb.rst create mode 100644 Documentation/devicetree/bindings/pci/endpoint/pci-epf-bus.yaml create mode 100644 Documentation/devicetree/bindings/pci/endpoint/pci-epf-device.yaml create mode 100644 Documentation/devicetree/bindings/pci/endpoint/pci-epf-ntb.yaml create mode 100644 drivers/ntb/hw/epf/Kconfig create mode 100644 drivers/ntb/hw/epf/Makefile create mode 100644 drivers/ntb/hw/epf/ntb_hw_epf.c create mode 100644 drivers/pci/endpoint/functions/pci-epf-ntb.c create mode 100644 drivers/pci/endpoint/pci-epf-bus.c