linux.git/drivers/thunderbolt/usb4.c, branch v6.8

thunderbolt: Fix setting the CNS bit in ROUTER_CS_5

2024-01-29T07:48:40+00:00

The bit 23, CM TBT3 Not Supported (CNS), in ROUTER_CS_5 indicates
whether a USB4 Connection Manager is TBT3-Compatible and should be:
    0b for TBT3-Compatible
    1b for Not TBT3-Compatible

Fixes: b04079837b20 ("thunderbolt: Add initial support for USB4")
Cc: stable@vger.kernel.org
Signed-off-by: Mohammad Rahimi 
Signed-off-by: Mika Westerberg

thunderbolt: Fix minimum allocated USB 3.x and PCIe bandwidth

2023-12-08T07:03:49+00:00

With the current bandwidth allocation we end up reserving too much for the USB
3.x and PCIe tunnels that leads to reduced capabilities for the second
DisplayPort tunnel.

Fix this by decreasing the USB 3.x allocation to 900 Mb/s which then allows
both tunnels to get the maximum HBR2 bandwidth.  This way, the reserved
bandwidth for USB 3.x and PCIe, would be 1350 Mb/s (taking weights of USB 3.x
and PCIe into account). So bandwidth allocations on a link are:
USB 3.x + PCIe tunnels => 1350 Mb/s
DisplayPort tunnel #1  => 17280 Mb/s
DisplayPort tunnel #2  => 17280 Mb/s

Total consumed bandwidth is 35910 Mb/s. So that all the above can be tunneled
on a Gen 3 link (which allows maximum of 36000 Mb/s).

Fixes: 582e70b0d3a4 ("thunderbolt: Change bandwidth reservations to comply USB4 v2")
Signed-off-by: Gil Fine 
Signed-off-by: Mika Westerberg

thunderbolt: Add support for asymmetric link

2023-10-20T15:18:01+00:00

USB4 v2 spec defines a Gen 4 link that can operate as an aggregated
symmetric (80/80G) or asymmetric (120/40G). When the link is asymmetric,
the USB4 port on one side of the link operates with three TX lanes and
one RX lane, while the USB4 port on the opposite side of the link
operates with three RX lanes and one TX lane.

Add support for the asymmetric link and provide functions that can be
used to transition the link to asymmetric and back.

Signed-off-by: Gil Fine 
Co-developed-by: Mika Westerberg 
Signed-off-by: Mika Westerberg

thunderbolt: Get rid of usb4_usb3_port_actual_link_rate()

2023-10-13T05:49:13+00:00

It turns out there is no need to use the actual link rate when
reclaiming bandwidth for USB 3.x. The reason is that we use consumed
bandwidth which is coming from xHCI when releasing bandwidth (for
example for DisplayPort tunneling) and this can be anything between
1000 Mb/s to maximum, so when reclaiming we can just bump it up back to
maximum instead of actual link rate (which is always <= maximum).

This allows us to get rid of couple of unnecessary lines of code.

Signed-off-by: Mika Westerberg

thunderbolt: Make bandwidth allocation mode function names consistent

2023-06-16T06:53:29+00:00

Make sure the DisplayPort bandwidth allocation mode function names are
consistent with the existing ones, such as USB3.

No functional changes.

Signed-off-by: Mika Westerberg

thunderbolt: Add support for enhanced uni-directional TMU mode

2023-06-16T06:53:28+00:00

This is new TMU mode introduced with the USB4 v2. This mode is simpler
than the existing ones and allows all CL states as well. Enable this for
all links where both side routers are v2 and keep the existing
functionality for the v1 and earlier links.

Currently only support the MedRes rate. We can add the HiFi rate later
too if it turns out to be useful.

Signed-off-by: Mika Westerberg

thunderbolt: Move constants related to NVM into nvm.c

2023-06-16T06:53:28+00:00

Move constants related to NVM into nvm.c to make the code cleaner. Use a
separate constant for USB4_DATA_DWORDS in usb4.c.

No functional changes.

Signed-off-by: Gil Fine 
Signed-off-by: Mika Westerberg

thunderbolt: Enable USB4 v2 PCIe TLP/DLLP extended encapsulation

2023-06-16T06:53:28+00:00

USB4 v2 spec introduces modified encapsulation of PCIe TLP and DLLP
packets. This improves the PCIe tunneled traffic usage by reducing
overhead. Enable this if both sides of the link support it.

Signed-off-by: Gil Fine 
Signed-off-by: Mika Westerberg

thunderbolt: Introduce tb_switch_downstream_port()

2023-06-09T09:07:22+00:00

Introduce tb_switch_downstream_port() helper function that returns the
downstream port of a parent switch that is connected to the upstream
port of specified switch. From now on, we use it all across the driver
where applicable.

While there fix a whitespace in comment and rename 'downstream' to
'down' to be consistent with the rest of the driver.

Signed-off-by: Gil Fine 
Signed-off-by: Mika Westerberg

Merge tag 'thunderbolt-for-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into usb-next

2023-04-19T09:42:44+00:00

Mika writes:

thunderbolt: Changes for v6.4 merge window

This includes following Thunderbolt/USB4 changes for the v6.4 merge
window:

  - Refactoring of DROM read code paths
  - Convert to use SI units from units.h
  - A couple of cleanups

All these have been in linux-next with no reported issues.

* tag 'thunderbolt-for-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt:
  thunderbolt: Introduce usb4_port_sb_opcode_err_to_errno() helper
  thunderbolt: Make use of SI units from units.h
  thunderbolt: Get rid of redundant 'else'
  thunderbolt: Refactor DROM reading
  thunderbolt: use `tb_eeprom_get_drom_offset` to discover DROM offset