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diff --git a/Documentation/networking/device_drivers/qualcomm/rmnet.rst b/Documentation/networking/device_drivers/qualcomm/rmnet.rst deleted file mode 100644 index 70643b58de05..000000000000 --- a/Documentation/networking/device_drivers/qualcomm/rmnet.rst +++ /dev/null @@ -1,95 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -============ -Rmnet Driver -============ - -1. Introduction -=============== - -rmnet driver is used for supporting the Multiplexing and aggregation -Protocol (MAP). This protocol is used by all recent chipsets using Qualcomm -Technologies, Inc. modems. - -This driver can be used to register onto any physical network device in -IP mode. Physical transports include USB, HSIC, PCIe and IP accelerator. - -Multiplexing allows for creation of logical netdevices (rmnet devices) to -handle multiple private data networks (PDN) like a default internet, tethering, -multimedia messaging service (MMS) or IP media subsystem (IMS). Hardware sends -packets with MAP headers to rmnet. Based on the multiplexer id, rmnet -routes to the appropriate PDN after removing the MAP header. - -Aggregation is required to achieve high data rates. This involves hardware -sending aggregated bunch of MAP frames. rmnet driver will de-aggregate -these MAP frames and send them to appropriate PDN's. - -2. Packet format -================ - -a. MAP packet (data / control) - -MAP header has the same endianness of the IP packet. - -Packet format:: - - Bit 0 1 2-7 8 - 15 16 - 31 - Function Command / Data Reserved Pad Multiplexer ID Payload length - Bit 32 - x - Function Raw Bytes - -Command (1)/ Data (0) bit value is to indicate if the packet is a MAP command -or data packet. Control packet is used for transport level flow control. Data -packets are standard IP packets. - -Reserved bits are usually zeroed out and to be ignored by receiver. - -Padding is number of bytes to be added for 4 byte alignment if required by -hardware. - -Multiplexer ID is to indicate the PDN on which data has to be sent. - -Payload length includes the padding length but does not include MAP header -length. - -b. MAP packet (command specific):: - - Bit 0 1 2-7 8 - 15 16 - 31 - Function Command Reserved Pad Multiplexer ID Payload length - Bit 32 - 39 40 - 45 46 - 47 48 - 63 - Function Command name Reserved Command Type Reserved - Bit 64 - 95 - Function Transaction ID - Bit 96 - 127 - Function Command data - -Command 1 indicates disabling flow while 2 is enabling flow - -Command types - -= ========================================== -0 for MAP command request -1 is to acknowledge the receipt of a command -2 is for unsupported commands -3 is for error during processing of commands -= ========================================== - -c. Aggregation - -Aggregation is multiple MAP packets (can be data or command) delivered to -rmnet in a single linear skb. rmnet will process the individual -packets and either ACK the MAP command or deliver the IP packet to the -network stack as needed - -MAP header|IP Packet|Optional padding|MAP header|IP Packet|Optional padding.... - -MAP header|IP Packet|Optional padding|MAP header|Command Packet|Optional pad... - -3. Userspace configuration -========================== - -rmnet userspace configuration is done through netlink library librmnetctl -and command line utility rmnetcli. Utility is hosted in codeaurora forum git. -The driver uses rtnl_link_ops for communication. - -https://source.codeaurora.org/quic/la/platform/vendor/qcom-opensource/dataservices/tree/rmnetctl |