When device side MTU is larger than host side MTU, the packets
(typically rmnet packets) are split over multiple MHI transfers.
In that case, fragments must be re-aggregated to recover the packet
before forwarding to upper layer.
A fragmented packet result in -EOVERFLOW MHI transaction status for
each of its fragments, except the final one. Such transfer was
previously considered as error and fragments were simply dropped.
This change adds re-aggregation mechanism using skb chaining, via
skb frag_list.
A warning (once) is printed since this behavior usually comes from
a misconfiguration of the device (e.g. modem MTU).
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Link: https://lore.kernel.org/r/1612428002-12333-1-git-send-email-loic.poulain@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the new mhi_get_free_desc_count helper to track queue usage
instead of relying on the locally maintained rx_queued count.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The RX queue size can be determined at runtime by retrieving the
number of available transfer descriptors.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The 'wwan' devtype is meant for devices that require additional
configuration to be used, like WWAN specific APN setup over AT/QMI
commands, rmnet link creation, etc. This is the case for MHI (Modem
host Interface) netdev which targets modem/WWAN endpoints.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/1611328554-1414-1-git-send-email-loic.poulain@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
MHI net is protocol agnostic, the payload protocol depends on the modem
configuration, which can be either RMNET (IP muxing and aggregation) or
raw IP. This patch adds support for incomming IPv4/IPv6 packets, that
was previously unconditionnaly reported as RMNET packets.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch checks that MHI queue is not full before waking up the net
queue. This fix sporadic MHI queueing issues in xmit. Indeed xmit and
its symmetric complete callback (ul_callback) can run concurently, it
is then not safe to unconditionnaly waking the queue in the callback
without checking queue fullness.
Fixes: 3ffec6a14f ("net: Add mhi-net driver")
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/1607599507-5879-1-git-send-email-loic.poulain@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch adds a new network driver implementing MHI transport for
network packets. Packets can be in any format, though QMAP (rmnet)
is the usual protocol (flow control + PDN mux).
It support two MHI devices, IP_HW0 which is, the path to the IPA
(IP accelerator) on qcom modem, And IP_SW0 which is the software
driven IP path (to modem CPU).
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1604424234-24446-2-git-send-email-loic.poulain@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
