Add bnxt_fwctl to the driver and fwctl documentation pages. Reviewed-by: Andy Gospodarek Signed-off-by: Pavan Chebbi --- .../userspace-api/fwctl/bnxt_fwctl.rst | 78 +++++++++++++++++++ Documentation/userspace-api/fwctl/fwctl.rst | 1 + Documentation/userspace-api/fwctl/index.rst | 1 + 3 files changed, 80 insertions(+) create mode 100644 Documentation/userspace-api/fwctl/bnxt_fwctl.rst diff --git a/Documentation/userspace-api/fwctl/bnxt_fwctl.rst b/Documentation/userspace-api/fwctl/bnxt_fwctl.rst new file mode 100644 index 000000000000..7cf2b65ea34b --- /dev/null +++ b/Documentation/userspace-api/fwctl/bnxt_fwctl.rst @@ -0,0 +1,78 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================= +fwctl bnxt driver +================= + +:Author: Pavan Chebbi + +Overview +======== + +BNXT driver makes a fwctl service available through an auxiliary_device. +The bnxt_fwctl driver binds to this device and registers itself with the +fwctl subsystem. + +The bnxt_fwctl driver is agnostic to the device firmware internals. It +uses the Upper Layer Protocol (ULP) conduit provided by bnxt to send +HardWare Resource Manager (HWRM) commands to firmware. + +These commands can query or change firmware driven device configurations +and read/write registers that are useful for debugging. + +bnxt_fwctl User API +=================== + +Each RPC request contains a message request structure (HWRM input), +its length, optional request timeout, and dma buffers' information +if the command needs any DMA. The request is then put together with +the request data and sent through bnxt's message queue to the firmware, +and the results are returned to the caller. + +A typical user application can send a FWCTL_INFO command using ioctl() +to discover bnxt_fwctl's RPC capabilities as shown below: + + ioctl(fd, FWCTL_INFO, &fwctl_info_msg); + +where fwctl_info_msg (of type struct fwctl_info) describes bnxt_info_msg +(of type struct fwctl_info_bnxt) as shown below: + + size = sizeof(fwctl_info_msg); + flags = 0; + device_data_len = sizeof(bnxt_info_msg); + out_device_data = (__aligned_u64)&bnxt_info_msg; + +The uctx_caps of bnxt_info_msg represents the capabilities as described +in fwctl_bnxt_commands of include/uapi/fwctl/bnxt.h + +The FW RPC itself, FWCTL_RPC can be sent using ioctl() as: + + ioctl(fd, FWCTL_RPC, &fwctl_rpc_msg); + +where fwctl_rpc_msg (of type struct fwctl_rpc) encapsulates fwctl_rpc_bnxt +(see bnxt_rpc_msg below). fwctl_rpc_bnxt members are set up as per the +requirements of specific HWRM commands described in include/linux/bnxt/hsi.h. +An example for HWRM_VER_GET is shown below: + + struct fwctl_rpc_bnxt bnxt_rpc_msg; + struct hwrm_ver_get_output resp; + struct fwctl_rpc fwctl_rpc_msg; + struct hwrm_ver_get_input req; + + req.req_type = HWRM_VER_GET; + req.hwrm_intf_maj = HWRM_VERSION_MAJOR; + req.hwrm_intf_min = HWRM_VERSION_MINOR; + req.hwrm_intf_upd = HWRM_VERSION_UPDATE; + req.cmpl_ring = -1; + req.target_id = -1; + + bnxt_rpc_msg.req_len = sizeof(req); + bnxt_rpc_msg.num_dma = 0; + bnxt_rpc_msg.req = (__aligned_u64)&req; + + fwctl_rpc_msg.size = sizeof(fwctl_rpc_msg); + fwctl_rpc_msg.scope = FWCTL_RPC_DEBUG_READ_ONLY; + fwctl_rpc_msg.in_len = sizeof(bnxt_rpc_msg) + sizeof(req); + fwctl_rpc_msg.out_len = sizeof(resp); + fwctl_rpc_msg.in = (__aligned_u64)&bnxt_rpc_msg; + fwctl_rpc_msg.out = (__aligned_u64)&resp; diff --git a/Documentation/userspace-api/fwctl/fwctl.rst b/Documentation/userspace-api/fwctl/fwctl.rst index a74eab8d14c6..826817bfd54d 100644 --- a/Documentation/userspace-api/fwctl/fwctl.rst +++ b/Documentation/userspace-api/fwctl/fwctl.rst @@ -148,6 +148,7 @@ area resulting in clashes will be resolved in favour of a kernel implementation. fwctl User API ============== +.. kernel-doc:: include/uapi/fwctl/bnxt.h .. kernel-doc:: include/uapi/fwctl/fwctl.h .. kernel-doc:: include/uapi/fwctl/mlx5.h .. kernel-doc:: include/uapi/fwctl/pds.h diff --git a/Documentation/userspace-api/fwctl/index.rst b/Documentation/userspace-api/fwctl/index.rst index 316ac456ad3b..8062f7629654 100644 --- a/Documentation/userspace-api/fwctl/index.rst +++ b/Documentation/userspace-api/fwctl/index.rst @@ -10,5 +10,6 @@ to securely construct and execute RPCs inside device firmware. :maxdepth: 1 fwctl + bnxt_fwctl fwctl-cxl pds_fwctl -- 2.39.1