| .. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
| |
| ==================================== |
| Marvell OcteonTx2 RVU Kernel Drivers |
| ==================================== |
| |
| Copyright (c) 2020 Marvell International Ltd. |
| |
| Contents |
| ======== |
| |
| - `Overview`_ |
| - `Drivers`_ |
| - `Basic packet flow`_ |
| - `Devlink health reporters`_ |
| |
| Overview |
| ======== |
| |
| Resource virtualization unit (RVU) on Marvell's OcteonTX2 SOC maps HW |
| resources from the network, crypto and other functional blocks into |
| PCI-compatible physical and virtual functions. Each functional block |
| again has multiple local functions (LFs) for provisioning to PCI devices. |
| RVU supports multiple PCIe SRIOV physical functions (PFs) and virtual |
| functions (VFs). PF0 is called the administrative / admin function (AF) |
| and has privileges to provision RVU functional block's LFs to each of the |
| PF/VF. |
| |
| RVU managed networking functional blocks |
| - Network pool or buffer allocator (NPA) |
| - Network interface controller (NIX) |
| - Network parser CAM (NPC) |
| - Schedule/Synchronize/Order unit (SSO) |
| - Loopback interface (LBK) |
| |
| RVU managed non-networking functional blocks |
| - Crypto accelerator (CPT) |
| - Scheduled timers unit (TIM) |
| - Schedule/Synchronize/Order unit (SSO) |
| Used for both networking and non networking usecases |
| |
| Resource provisioning examples |
| - A PF/VF with NIX-LF & NPA-LF resources works as a pure network device |
| - A PF/VF with CPT-LF resource works as a pure crypto offload device. |
| |
| RVU functional blocks are highly configurable as per software requirements. |
| |
| Firmware setups following stuff before kernel boots |
| - Enables required number of RVU PFs based on number of physical links. |
| - Number of VFs per PF are either static or configurable at compile time. |
| Based on config, firmware assigns VFs to each of the PFs. |
| - Also assigns MSIX vectors to each of PF and VFs. |
| - These are not changed after kernel boot. |
| |
| Drivers |
| ======= |
| |
| Linux kernel will have multiple drivers registering to different PF and VFs |
| of RVU. Wrt networking there will be 3 flavours of drivers. |
| |
| Admin Function driver |
| --------------------- |
| |
| As mentioned above RVU PF0 is called the admin function (AF), this driver |
| supports resource provisioning and configuration of functional blocks. |
| Doesn't handle any I/O. It sets up few basic stuff but most of the |
| funcionality is achieved via configuration requests from PFs and VFs. |
| |
| PF/VFs communicates with AF via a shared memory region (mailbox). Upon |
| receiving requests AF does resource provisioning and other HW configuration. |
| AF is always attached to host kernel, but PFs and their VFs may be used by host |
| kernel itself, or attached to VMs or to userspace applications like |
| DPDK etc. So AF has to handle provisioning/configuration requests sent |
| by any device from any domain. |
| |
| AF driver also interacts with underlying firmware to |
| - Manage physical ethernet links ie CGX LMACs. |
| - Retrieve information like speed, duplex, autoneg etc |
| - Retrieve PHY EEPROM and stats. |
| - Configure FEC, PAM modes |
| - etc |
| |
| From pure networking side AF driver supports following functionality. |
| - Map a physical link to a RVU PF to which a netdev is registered. |
| - Attach NIX and NPA block LFs to RVU PF/VF which provide buffer pools, RQs, SQs |
| for regular networking functionality. |
| - Flow control (pause frames) enable/disable/config. |
| - HW PTP timestamping related config. |
| - NPC parser profile config, basically how to parse pkt and what info to extract. |
| - NPC extract profile config, what to extract from the pkt to match data in MCAM entries. |
| - Manage NPC MCAM entries, upon request can frame and install requested packet forwarding rules. |
| - Defines receive side scaling (RSS) algorithms. |
| - Defines segmentation offload algorithms (eg TSO) |
| - VLAN stripping, capture and insertion config. |
| - SSO and TIM blocks config which provide packet scheduling support. |
| - Debugfs support, to check current resource provising, current status of |
| NPA pools, NIX RQ, SQ and CQs, various stats etc which helps in debugging issues. |
| - And many more. |
| |
| Physical Function driver |
| ------------------------ |
| |
| This RVU PF handles IO, is mapped to a physical ethernet link and this |
| driver registers a netdev. This supports SR-IOV. As said above this driver |
| communicates with AF with a mailbox. To retrieve information from physical |
| links this driver talks to AF and AF gets that info from firmware and responds |
| back ie cannot talk to firmware directly. |
| |
| Supports ethtool for configuring links, RSS, queue count, queue size, |
| flow control, ntuple filters, dump PHY EEPROM, config FEC etc. |
| |
| Virtual Function driver |
| ----------------------- |
| |
| There are two types VFs, VFs that share the physical link with their parent |
| SR-IOV PF and the VFs which work in pairs using internal HW loopback channels (LBK). |
| |
| Type1: |
| - These VFs and their parent PF share a physical link and used for outside communication. |
| - VFs cannot communicate with AF directly, they send mbox message to PF and PF |
| forwards that to AF. AF after processing, responds back to PF and PF forwards |
| the reply to VF. |
| - From functionality point of view there is no difference between PF and VF as same type |
| HW resources are attached to both. But user would be able to configure few stuff only |
| from PF as PF is treated as owner/admin of the link. |
| |
| Type2: |
| - RVU PF0 ie admin function creates these VFs and maps them to loopback block's channels. |
| - A set of two VFs (VF0 & VF1, VF2 & VF3 .. so on) works as a pair ie pkts sent out of |
| VF0 will be received by VF1 and viceversa. |
| - These VFs can be used by applications or virtual machines to communicate between them |
| without sending traffic outside. There is no switch present in HW, hence the support |
| for loopback VFs. |
| - These communicate directly with AF (PF0) via mbox. |
| |
| Except for the IO channels or links used for packet reception and transmission there is |
| no other difference between these VF types. AF driver takes care of IO channel mapping, |
| hence same VF driver works for both types of devices. |
| |
| Basic packet flow |
| ================= |
| |
| Ingress |
| ------- |
| |
| 1. CGX LMAC receives packet. |
| 2. Forwards the packet to the NIX block. |
| 3. Then submitted to NPC block for parsing and then MCAM lookup to get the destination RVU device. |
| 4. NIX LF attached to the destination RVU device allocates a buffer from RQ mapped buffer pool of NPA block LF. |
| 5. RQ may be selected by RSS or by configuring MCAM rule with a RQ number. |
| 6. Packet is DMA'ed and driver is notified. |
| |
| Egress |
| ------ |
| |
| 1. Driver prepares a send descriptor and submits to SQ for transmission. |
| 2. The SQ is already configured (by AF) to transmit on a specific link/channel. |
| 3. The SQ descriptor ring is maintained in buffers allocated from SQ mapped pool of NPA block LF. |
| 4. NIX block transmits the pkt on the designated channel. |
| 5. NPC MCAM entries can be installed to divert pkt onto a different channel. |
| |
| Devlink health reporters |
| ======================== |
| |
| NPA Reporters |
| ------------- |
| The NPA reporters are responsible for reporting and recovering the following group of errors: |
| |
| 1. GENERAL events |
| |
| - Error due to operation of unmapped PF. |
| - Error due to disabled alloc/free for other HW blocks (NIX, SSO, TIM, DPI and AURA). |
| |
| 2. ERROR events |
| |
| - Fault due to NPA_AQ_INST_S read or NPA_AQ_RES_S write. |
| - AQ Doorbell Error. |
| |
| 3. RAS events |
| |
| - RAS Error Reporting for NPA_AQ_INST_S/NPA_AQ_RES_S. |
| |
| 4. RVU events |
| |
| - Error due to unmapped slot. |
| |
| Sample Output:: |
| |
| ~# devlink health |
| pci/0002:01:00.0: |
| reporter hw_npa_intr |
| state healthy error 2872 recover 2872 last_dump_date 2020-12-10 last_dump_time 09:39:09 grace_period 0 auto_recover true auto_dump true |
| reporter hw_npa_gen |
| state healthy error 2872 recover 2872 last_dump_date 2020-12-11 last_dump_time 04:43:04 grace_period 0 auto_recover true auto_dump true |
| reporter hw_npa_err |
| state healthy error 2871 recover 2871 last_dump_date 2020-12-10 last_dump_time 09:39:17 grace_period 0 auto_recover true auto_dump true |
| reporter hw_npa_ras |
| state healthy error 0 recover 0 last_dump_date 2020-12-10 last_dump_time 09:32:40 grace_period 0 auto_recover true auto_dump true |
| |
| Each reporter dumps the |
| |
| - Error Type |
| - Error Register value |
| - Reason in words |
| |
| For example:: |
| |
| ~# devlink health dump show pci/0002:01:00.0 reporter hw_npa_gen |
| NPA_AF_GENERAL: |
| NPA General Interrupt Reg : 1 |
| NIX0: free disabled RX |
| ~# devlink health dump show pci/0002:01:00.0 reporter hw_npa_intr |
| NPA_AF_RVU: |
| NPA RVU Interrupt Reg : 1 |
| Unmap Slot Error |
| ~# devlink health dump show pci/0002:01:00.0 reporter hw_npa_err |
| NPA_AF_ERR: |
| NPA Error Interrupt Reg : 4096 |
| AQ Doorbell Error |
| |
| |
| NIX Reporters |
| ------------- |
| The NIX reporters are responsible for reporting and recovering the following group of errors: |
| |
| 1. GENERAL events |
| |
| - Receive mirror/multicast packet drop due to insufficient buffer. |
| - SMQ Flush operation. |
| |
| 2. ERROR events |
| |
| - Memory Fault due to WQE read/write from multicast/mirror buffer. |
| - Receive multicast/mirror replication list error. |
| - Receive packet on an unmapped PF. |
| - Fault due to NIX_AQ_INST_S read or NIX_AQ_RES_S write. |
| - AQ Doorbell Error. |
| |
| 3. RAS events |
| |
| - RAS Error Reporting for NIX Receive Multicast/Mirror Entry Structure. |
| - RAS Error Reporting for WQE/Packet Data read from Multicast/Mirror Buffer.. |
| - RAS Error Reporting for NIX_AQ_INST_S/NIX_AQ_RES_S. |
| |
| 4. RVU events |
| |
| - Error due to unmapped slot. |
| |
| Sample Output:: |
| |
| ~# ./devlink health |
| pci/0002:01:00.0: |
| reporter hw_npa_intr |
| state healthy error 0 recover 0 grace_period 0 auto_recover true auto_dump true |
| reporter hw_npa_gen |
| state healthy error 0 recover 0 grace_period 0 auto_recover true auto_dump true |
| reporter hw_npa_err |
| state healthy error 0 recover 0 grace_period 0 auto_recover true auto_dump true |
| reporter hw_npa_ras |
| state healthy error 0 recover 0 grace_period 0 auto_recover true auto_dump true |
| reporter hw_nix_intr |
| state healthy error 1121 recover 1121 last_dump_date 2021-01-19 last_dump_time 05:42:26 grace_period 0 auto_recover true auto_dump true |
| reporter hw_nix_gen |
| state healthy error 949 recover 949 last_dump_date 2021-01-19 last_dump_time 05:42:43 grace_period 0 auto_recover true auto_dump true |
| reporter hw_nix_err |
| state healthy error 1147 recover 1147 last_dump_date 2021-01-19 last_dump_time 05:42:59 grace_period 0 auto_recover true auto_dump true |
| reporter hw_nix_ras |
| state healthy error 409 recover 409 last_dump_date 2021-01-19 last_dump_time 05:43:16 grace_period 0 auto_recover true auto_dump true |
| |
| Each reporter dumps the |
| |
| - Error Type |
| - Error Register value |
| - Reason in words |
| |
| For example:: |
| |
| ~# devlink health dump show pci/0002:01:00.0 reporter hw_nix_intr |
| NIX_AF_RVU: |
| NIX RVU Interrupt Reg : 1 |
| Unmap Slot Error |
| ~# devlink health dump show pci/0002:01:00.0 reporter hw_nix_gen |
| NIX_AF_GENERAL: |
| NIX General Interrupt Reg : 1 |
| Rx multicast pkt drop |
| ~# devlink health dump show pci/0002:01:00.0 reporter hw_nix_err |
| NIX_AF_ERR: |
| NIX Error Interrupt Reg : 64 |
| Rx on unmapped PF_FUNC |
