diff options
| author | Sanath S <Sanath.S@amd.com> | 2024-01-13 12:52:48 +0300 |
|---|---|---|
| committer | Mika Westerberg <mika.westerberg@linux.intel.com> | 2024-01-22 14:21:06 +0300 |
| commit | 59a54c5f3dbde00b8ad30aef27fe35b1fe07bf5c (patch) | |
| tree | 0d4f433a41c3b6d9dabc1a076d7b45f0c6437f1b /drivers/thunderbolt/tb.c | |
| parent | ec8162b3f0683ae08a21f20517cf49272b07ee0b (diff) | |
| download | linux-59a54c5f3dbde00b8ad30aef27fe35b1fe07bf5c.tar.xz | |
thunderbolt: Reset topology created by the boot firmware
Boot firmware (typically BIOS) might have created tunnels of its own.
The tunnel configuration that it does might be sub-optimal. For instance
it may only support HBR2 monitors so the DisplayPort tunnels it created
may limit Linux graphics drivers. In addition there is an issue on some
AMD based systems where the BIOS does not allocate enough PCIe resources
for future topology extension. By resetting the USB4 topology the PCIe
links will be reset as well allowing Linux to re-allocate.
This aligns the behavior with Windows Connection Manager.
We already issued host router reset for USB4 v2 routers, now extend it
to USB4 v1 routers as well. For pre-USB4 (that's Apple systems) we leave
it as is and continue to discover the existing tunnels.
Suggested-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Sanath S <Sanath.S@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Diffstat (limited to 'drivers/thunderbolt/tb.c')
| -rw-r--r-- | drivers/thunderbolt/tb.c | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c index 846d2813bb1a..9a261560d0f4 100644 --- a/drivers/thunderbolt/tb.c +++ b/drivers/thunderbolt/tb.c @@ -2581,7 +2581,7 @@ static int tb_scan_finalize_switch(struct device *dev, void *data) return 0; } -static int tb_start(struct tb *tb) +static int tb_start(struct tb *tb, bool reset) { struct tb_cm *tcm = tb_priv(tb); int ret; @@ -2622,12 +2622,24 @@ static int tb_start(struct tb *tb) tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_MODE_LOWRES); /* Enable TMU if it is off */ tb_switch_tmu_enable(tb->root_switch); - /* Full scan to discover devices added before the driver was loaded. */ - tb_scan_switch(tb->root_switch); - /* Find out tunnels created by the boot firmware */ - tb_discover_tunnels(tb); - /* Add DP resources from the DP tunnels created by the boot firmware */ - tb_discover_dp_resources(tb); + + /* + * Boot firmware might have created tunnels of its own. Since we + * cannot be sure they are usable for us, tear them down and + * reset the ports to handle it as new hotplug for USB4 v1 + * routers (for USB4 v2 and beyond we already do host reset). + */ + if (reset && usb4_switch_version(tb->root_switch) == 1) { + tb_switch_reset(tb->root_switch); + } else { + /* Full scan to discover devices added before the driver was loaded. */ + tb_scan_switch(tb->root_switch); + /* Find out tunnels created by the boot firmware */ + tb_discover_tunnels(tb); + /* Add DP resources from the DP tunnels created by the boot firmware */ + tb_discover_dp_resources(tb); + } + /* * If the boot firmware did not create USB 3.x tunnels create them * now for the whole topology. |