From acfcf23597d62700f1c8e1975bca34070e0251ef Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Fri, 1 May 2020 16:44:51 +0200 Subject: docs: networking: device drivers: convert qualcomm/rmnet.txt to ReST - add SPDX header; - add a document title; - mark code blocks and literals as such; - mark tables as such; - adjust identation, whitespaces and blank lines where needed; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: David S. Miller --- Documentation/networking/device_drivers/index.rst | 1 + .../networking/device_drivers/qualcomm/rmnet.rst | 95 ++++++++++++++++++++++ .../networking/device_drivers/qualcomm/rmnet.txt | 82 ------------------- 3 files changed, 96 insertions(+), 82 deletions(-) create mode 100644 Documentation/networking/device_drivers/qualcomm/rmnet.rst delete mode 100644 Documentation/networking/device_drivers/qualcomm/rmnet.txt (limited to 'Documentation') diff --git a/Documentation/networking/device_drivers/index.rst b/Documentation/networking/device_drivers/index.rst index 55837244eaad..66ed884548cc 100644 --- a/Documentation/networking/device_drivers/index.rst +++ b/Documentation/networking/device_drivers/index.rst @@ -44,6 +44,7 @@ Contents: microsoft/netvsc neterion/s2io neterion/vxge + qualcomm/rmnet .. only:: subproject and html diff --git a/Documentation/networking/device_drivers/qualcomm/rmnet.rst b/Documentation/networking/device_drivers/qualcomm/rmnet.rst new file mode 100644 index 000000000000..70643b58de05 --- /dev/null +++ b/Documentation/networking/device_drivers/qualcomm/rmnet.rst @@ -0,0 +1,95 @@ +.. 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 diff --git a/Documentation/networking/device_drivers/qualcomm/rmnet.txt b/Documentation/networking/device_drivers/qualcomm/rmnet.txt deleted file mode 100644 index 6b341eaf2062..000000000000 --- a/Documentation/networking/device_drivers/qualcomm/rmnet.txt +++ /dev/null @@ -1,82 +0,0 @@ -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 -- cgit v1.2.3