Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 215 insertions, 0 deletions

diff --git a/Documentation/networking/device_drivers/cellular/index.rst b/Documentation/networking/device_drivers/cellular/index.rst
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index 000000000..fc1812d3f
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+.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+Cellular Modem Device Drivers
+=============================
+
+Contents:
+
+.. toctree::
+   :maxdepth: 2
+
+   qualcomm/rmnet
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`
diff --git a/Documentation/networking/device_drivers/cellular/qualcomm/rmnet.rst b/Documentation/networking/device_drivers/cellular/qualcomm/rmnet.rst
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index 000000000..4118384cf
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+.. 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 v1 (data / control)
+
+MAP header fields are in big endian format.
+
+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. Command packet is used for transport level flow control. Data
+packets are standard IP packets.
+
+Reserved bits must be zero when sent and ignored when received.
+
+Padding is the number of bytes to be appended to the payload to
+ensure 4 byte alignment.
+
+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 v4 (data / control)
+
+MAP header fields are in big endian format.
+
+Packet format::
+
+  Bit             0             1           2-7      8-15           16-31
+  Function   Command / Data   Reserved     Pad   Multiplexer ID    Payload length
+
+  Bit            32-(x-33)      (x-32)-x
+  Function      Raw bytes      Checksum offload header
+
+Command (1)/ Data (0) bit value is to indicate if the packet is a MAP command
+or data packet. Command packet is used for transport level flow control. Data
+packets are standard IP packets.
+
+Reserved bits must be zero when sent and ignored when received.
+
+Padding is the number of bytes to be appended to the payload to
+ensure 4 byte alignment.
+
+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.
+
+Checksum offload header, has the information about the checksum processing done
+by the hardware.Checksum offload header fields are in big endian format.
+
+Packet format::
+
+  Bit             0-14        15              16-31
+  Function      Reserved   Valid     Checksum start offset
+
+  Bit                31-47                    48-64
+  Function      Checksum length           Checksum value
+
+Reserved bits must be zero when sent and ignored when received.
+
+Valid bit indicates whether the partial checksum is calculated and is valid.
+Set to 1, if its is valid. Set to 0 otherwise.
+
+Padding is the number of bytes to be appended to the payload to
+ensure 4 byte alignment.
+
+Checksum start offset, Indicates the offset in bytes from the beginning of the
+IP header, from which modem computed checksum.
+
+Checksum length is the Length in bytes starting from CKSUM_START_OFFSET,
+over which checksum is computed.
+
+Checksum value, indicates the checksum computed.
+
+c. MAP packet v5 (data / control)
+
+MAP header fields are in big endian format.
+
+Packet format::
+
+  Bit             0             1         2-7      8-15           16-31
+  Function   Command / Data  Next header  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. Command packet is used for transport level flow control. Data
+packets are standard IP packets.
+
+Next header is used to indicate the presence of another header, currently is
+limited to checksum header.
+
+Padding is the number of bytes to be appended to the payload to
+ensure 4 byte alignment.
+
+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.
+
+d. Checksum offload header v5
+
+Checksum offload header fields are in big endian format.
+
+  Bit            0 - 6          7               8-15              16-31
+  Function     Header Type    Next Header     Checksum Valid    Reserved
+
+Header Type is to indicate the type of header, this usually is set to CHECKSUM
+
+Header types
+= ==========================================
+0 Reserved
+1 Reserved
+2 checksum header
+
+Checksum Valid is to indicate whether the header checksum is valid. Value of 1
+implies that checksum is calculated on this packet and is valid, value of 0
+indicates that the calculated packet checksum is invalid.
+
+Reserved bits must be zero when sent and ignored when received.
+
+e. MAP packet v1/v5 (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
+= ==========================================
+
+f. 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