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>
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