linux-toradex.git/drivers/thunderbolt/switch.c, branch v5.5

thunderbolt: Power cycle the router if NVM authentication fails

2019-11-19T16:35:57+00:00

On zang's Dell XPS 13 9370 after Thunderbolt NVM firmware upgrade the
Thunderbolt controller did not come back as expected. Only after the
system was rebooted it became available again. It is not entirely clear
what happened but I suspect the new NVM firmware image authentication
failed for some reason. Regardless of this the router needs to be power
cycled if NVM authentication fails in order to get it fully functional
again.

This modifies the driver to issue a power cycle in case the NVM
authentication fails immediately when dma_port_flash_update_auth()
returns. We also need to call tb_switch_set_uuid() earlier to be able to
fetch possible NVM authentication failure when DMA port is added.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=205457
Reported-by: zang 
Cc: stable 
Signed-off-by: Mika Westerberg 
Signed-off-by: Greg Kroah-Hartman

thunderbolt: Add Display Port adapter pairing and resource management

2019-11-02T09:13:31+00:00

To perform proper Display Port tunneling for Thunderbolt 3 devices we
need to allocate DP resources for DP IN port before they can be used.
The reason for this is that the user can also connect a monitor directly
to the Type-C ports in which case the Thunderbolt controller acts as
re-driver for Display Port (no tunneling takes place) taking the DP
sinks away from the connection manager. This allocation is done using
special sink allocation registers available through the link controller.

We can pair DP IN to DP OUT only if

 * DP IN has sink allocated via link controller
 * DP OUT port receives hotplug event

For DP IN adapters (only for the host router) we first query whether
there is DP resource available (it may be the previous instance of the
driver for example already allocated it) and if it is we add it to the
list. We then update the list when after each plug/unplug event to a DP
IN/OUT adapter. Each time the list is updated we try to find additional
DP IN <-> DP OUT pairs for tunnel establishment. This strategy also
makes it possible to establish another tunnel in case there are 3
monitors connected and one gets unplugged releasing the DP IN adapter
for the new tunnel.

Signed-off-by: Mika Westerberg

thunderbolt: Add default linking between lane adapters if not provided by DROM

2019-11-02T09:13:31+00:00

We currently read how sibling lane adapter ports relate each other from
DROM (Device ROM). If the two lane adapter ports go through the same
physical connector these lanes can then be bonded together. However,
some cases DROM does not provide this information or it is missing
completely (host routers typically do not have DROM). In this case we
have hard-coded the relationship.

Expand this to work with both legacy devices where lane adapter ports 1
and 2, and 3 and 4 are always linked together, and with USB4 devices
where lane adapter 1 is always following lane adapter 0 or is disabled
completely (see USB4 section 5.2.1 for more information).

Signed-off-by: Mika Westerberg

thunderbolt: Add support for lane bonding

2019-11-02T09:13:31+00:00

Lane bonding allows aggregating two 10/20 Gb/s (depending on the
generation) lanes into a single 20/40 Gb/s bonded link. This allows
sharing the full bandwidth more efficiently. In order to establish lane
bonding we need to check that lane bonding is possible through link
controller and that both ends of the link actually supports 2x widths.
This also means that all the paths should be established through the
primary port so update tb_path_alloc() to handle this as well.

Lane bonding is supported starting from Falcon Ridge (2nd generation)
controllers.

We also expose the current speed and number of lanes under each device
except the host router following similar attribute naming than USB bus.
Expose speed and number of lanes for both directions to allow possibility
of asymmetric link in the future.

Signed-off-by: Mika Westerberg

thunderbolt: Add helper macro to iterate over switch ports

2019-11-01T11:32:00+00:00

There are quite many places in the driver where we iterate over each
port in the switch. To make it bit more convenient, add a macro that can
be used to iterate over each port and convert existing call sites to use it.

This is based on code by Lukas Wunner.

No functional changes.

Signed-off-by: Mika Westerberg

thunderbolt: Convert DP adapter register names to follow the USB4 spec

2019-11-01T11:32:00+00:00

Now that USB4 spec has names for these DP adapter registers we can use
them instead. This makes it easier to match certain register to the spec.

No functional changes.

Signed-off-by: Mika Westerberg

thunderbolt: Convert PCIe adapter register names to follow the USB4 spec

2019-11-01T11:31:59+00:00

Now that USB4 spec has names for these PCIe adapter registers we can use
them instead. This makes it easier to match certain register to the spec.

No functional changes.

Signed-off-by: Mika Westerberg

thunderbolt: Convert basic adapter register names to follow the USB4 spec

2019-11-01T11:31:59+00:00

Now that USB4 spec has names for these basic registers we can use them
instead. This makes it easier to match certain register to the spec.

No functional changes.

Signed-off-by: Mika Westerberg

thunderbolt: Log error if adding switch fails

2019-11-01T11:31:59+00:00

If we fail to add a switch for some reason log an error instead of
keeping silent. This is useful for debugging.

Signed-off-by: Mika Westerberg

thunderbolt: Introduce tb_switch_is_icm()

2019-11-01T11:31:59+00:00

We currently differentiate between SW CM (Software Connection Manager,
sometimes also called External Connection Manager) and ICM (Firmware
based Connection Manager, Internal Connection Manager) by looking
directly at the sw->config.enabled field which may be rather hard to
understand for the casual reader. For this reason introduce a wrapper
function with documentation that should make the intention more clear.

Signed-off-by: Mika Westerberg