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authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-05 20:13:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-05 20:13:21 -0700
commit47ec5303d73ea344e84f46660fff693c57641386 (patch)
treea2252debab749de29620c43285295d60c4741119 /Documentation/networking/device_drivers/cellular
parent8186749621ed6b8fc42644c399e8c755a2b6f630 (diff)
parentc1055b76ad00aed0e8b79417080f212d736246b6 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller: 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan. 2) Support UDP segmentation in code TSO code, from Eric Dumazet. 3) Allow flashing different flash images in cxgb4 driver, from Vishal Kulkarni. 4) Add drop frames counter and flow status to tc flower offloading, from Po Liu. 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni. 6) Various new indirect call avoidance, from Eric Dumazet and Brian Vazquez. 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from Yonghong Song. 8) Support querying and setting hardware address of a port function via devlink, use this in mlx5, from Parav Pandit. 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson. 10) Switch qca8k driver over to phylink, from Jonathan McDowell. 11) In bpftool, show list of processes holding BPF FD references to maps, programs, links, and btf objects. From Andrii Nakryiko. 12) Several conversions over to generic power management, from Vaibhav Gupta. 13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry Yakunin. 14) Various https url conversions, from Alexander A. Klimov. 15) Timestamping and PHC support for mscc PHY driver, from Antoine Tenart. 16) Support bpf iterating over tcp and udp sockets, from Yonghong Song. 17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov. 18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan. 19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several drivers. From Luc Van Oostenryck. 20) XDP support for xen-netfront, from Denis Kirjanov. 21) Support receive buffer autotuning in MPTCP, from Florian Westphal. 22) Support EF100 chip in sfc driver, from Edward Cree. 23) Add XDP support to mvpp2 driver, from Matteo Croce. 24) Support MPTCP in sock_diag, from Paolo Abeni. 25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic infrastructure, from Jakub Kicinski. 26) Several pci_ --> dma_ API conversions, from Christophe JAILLET. 27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel. 28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki. 29) Refactor a lot of networking socket option handling code in order to avoid set_fs() calls, from Christoph Hellwig. 30) Add rfc4884 support to icmp code, from Willem de Bruijn. 31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei. 32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin. 33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin. 34) Support TCP syncookies in MPTCP, from Flowian Westphal. 35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano Brivio. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits) net: thunderx: initialize VF's mailbox mutex before first usage usb: hso: remove bogus check for EINPROGRESS usb: hso: no complaint about kmalloc failure hso: fix bailout in error case of probe ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM selftests/net: relax cpu affinity requirement in msg_zerocopy test mptcp: be careful on subflow creation selftests: rtnetlink: make kci_test_encap() return sub-test result selftests: rtnetlink: correct the final return value for the test net: dsa: sja1105: use detected device id instead of DT one on mismatch tipc: set ub->ifindex for local ipv6 address ipv6: add ipv6_dev_find() net: openvswitch: silence suspicious RCU usage warning Revert "vxlan: fix tos value before xmit" ptp: only allow phase values lower than 1 period farsync: switch from 'pci_' to 'dma_' API wan: wanxl: switch from 'pci_' to 'dma_' API hv_netvsc: do not use VF device if link is down dpaa2-eth: Fix passing zero to 'PTR_ERR' warning net: macb: Properly handle phylink on at91sam9x ...
Diffstat (limited to 'Documentation/networking/device_drivers/cellular')
-rw-r--r--Documentation/networking/device_drivers/cellular/index.rst18
-rw-r--r--Documentation/networking/device_drivers/cellular/qualcomm/rmnet.rst95
2 files changed, 113 insertions, 0 deletions
diff --git a/Documentation/networking/device_drivers/cellular/index.rst b/Documentation/networking/device_drivers/cellular/index.rst
new file mode 100644
index 000000000000..fc1812d3fc70
--- /dev/null
+++ b/Documentation/networking/device_drivers/cellular/index.rst
@@ -0,0 +1,18 @@
+.. 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
new file mode 100644
index 000000000000..70643b58de05
--- /dev/null
+++ b/Documentation/networking/device_drivers/cellular/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