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Diffstat (limited to 'Documentation/networking/device_drivers/ethernet/huawei')
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diff --git a/Documentation/networking/device_drivers/ethernet/huawei/hinic3.rst b/Documentation/networking/device_drivers/ethernet/huawei/hinic3.rst new file mode 100644 index 000000000000..e3dfd083fa52 --- /dev/null +++ b/Documentation/networking/device_drivers/ethernet/huawei/hinic3.rst @@ -0,0 +1,137 @@ +.. SPDX-License-Identifier: GPL-2.0 + +===================================================================== +Linux kernel driver for Huawei Ethernet Device Driver (hinic3) family +===================================================================== + +Overview +======== + +The hinic3 is a network interface card (NIC) for Data Center. It supports +a range of link-speed devices (10GE, 25GE, 100GE, etc.). The hinic3 +devices can have multiple physical forms: LOM (Lan on Motherboard) NIC, +PCIe standard NIC, OCP (Open Compute Project) NIC, etc. + +The hinic3 driver supports the following features: +- IPv4/IPv6 TCP/UDP checksum offload +- TSO (TCP Segmentation Offload), LRO (Large Receive Offload) +- RSS (Receive Side Scaling) +- MSI-X interrupt aggregation configuration and interrupt adaptation. +- SR-IOV (Single Root I/O Virtualization). + +Content +======= + +- Supported PCI vendor ID/device IDs +- Source Code Structure of Hinic3 Driver +- Management Interface + +Supported PCI vendor ID/device IDs +================================== + +19e5:0222 - hinic3 PF/PPF +19e5:375F - hinic3 VF + +Prime Physical Function (PPF) is responsible for the management of the +whole NIC card. For example, clock synchronization between the NIC and +the host. Any PF may serve as a PPF. The PPF is selected dynamically. + +Source Code Structure of Hinic3 Driver +====================================== + +======================== ================================================ +hinic3_pci_id_tbl.h Supported device IDs +hinic3_hw_intf.h Interface between HW and driver +hinic3_queue_common.[ch] Common structures and methods for NIC queues +hinic3_common.[ch] Encapsulation of memory operations in Linux +hinic3_csr.h Register definitions in the BAR +hinic3_hwif.[ch] Interface for BAR +hinic3_eqs.[ch] Interface for AEQs and CEQs +hinic3_mbox.[ch] Interface for mailbox +hinic3_mgmt.[ch] Management interface based on mailbox and AEQ +hinic3_wq.[ch] Work queue data structures and interface +hinic3_cmdq.[ch] Command queue is used to post command to HW +hinic3_hwdev.[ch] HW structures and methods abstractions +hinic3_lld.[ch] Auxiliary driver adaptation layer +hinic3_hw_comm.[ch] Interface for common HW operations +hinic3_mgmt_interface.h Interface between firmware and driver +hinic3_hw_cfg.[ch] Interface for HW configuration +hinic3_irq.c Interrupt request +hinic3_netdev_ops.c Operations registered to Linux kernel stack +hinic3_nic_dev.h NIC structures and methods abstractions +hinic3_main.c Main Linux kernel driver +hinic3_nic_cfg.[ch] NIC service configuration +hinic3_nic_io.[ch] Management plane interface for TX and RX +hinic3_rss.[ch] Interface for Receive Side Scaling (RSS) +hinic3_rx.[ch] Interface for transmit +hinic3_tx.[ch] Interface for receive +hinic3_ethtool.c Interface for ethtool operations (ops) +hinic3_filter.c Interface for MAC address +======================== ================================================ + +Management Interface +==================== + +Asynchronous Event Queue (AEQ) +------------------------------ + +AEQ receives high priority events from the HW over a descriptor queue. +Every descriptor is a fixed size of 64 bytes. AEQ can receive solicited or +unsolicited events. Every device, VF or PF, can have up to 4 AEQs. +Every AEQ is associated to a dedicated IRQ. AEQ can receive multiple types +of events, but in practice the hinic3 driver ignores all events except for +2 mailbox related events. + +Mailbox +------- + +Mailbox is a communication mechanism between the hinic3 driver and the HW. +Each device has an independent mailbox. Driver can use the mailbox to send +requests to management. Driver receives mailbox messages, such as responses +to requests, over the AEQ (using event HINIC3_AEQ_FOR_MBOX). Due to the +limited size of mailbox data register, mailbox messages are sent +segment-by-segment. + +Every device can use its mailbox to post request to firmware. The mailbox +can also be used to post requests and responses between the PF and its VFs. + +Completion Event Queue (CEQ) +---------------------------- + +The implementation of CEQ is the same as AEQ. It receives completion events +from HW over a fixed size descriptor of 32 bits. Every device can have up +to 32 CEQs. Every CEQ has a dedicated IRQ. CEQ only receives solicited +events that are responses to requests from the driver. CEQ can receive +multiple types of events, but in practice the hinic3 driver ignores all +events except for HINIC3_CMDQ that represents completion of previously +posted commands on a cmdq. + +Command Queue (cmdq) +-------------------- + +Every cmdq has a dedicated work queue on which commands are posted. +Commands on the work queue are fixed size descriptor of size 64 bytes. +Completion of a command will be indicated using ctrl bits in the +descriptor that carried the command. Notification of command completions +will also be provided via event on CEQ. Every device has 4 command queues +that are initialized as a set (called cmdqs), each with its own type. +Hinic3 driver only uses type HINIC3_CMDQ_SYNC. + +Work Queues(WQ) +--------------- + +Work queues are logical arrays of fixed size WQEs. The array may be spread +over multiple non-contiguous pages using indirection table. Work queues are +used by I/O queues and command queues. + +Global function ID +------------------ + +Every function, PF or VF, has a unique ordinal identification within the device. +Many management commands (mbox or cmdq) contain this ID so HW can apply the +command effect to the right function. + +PF is allowed to post management commands to a subordinate VF by specifying the +VFs ID. A VF must provide its own ID. Anti-spoofing in the HW will cause +command from a VF to fail if it contains the wrong ID. + |