04c38bedd0
commit 582620d9f6b352552bc9a3316fe2b1c3acd8742d upstream. On some systems the IOMMU blocks the first couple of driver ready messages to the connection manager firmware as can be seen in below excerpts: thunderbolt 0000:06:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0010 address=0xbb0e3400 flags=0x0020] or DMAR: DRHD: handling fault status reg 2 DMAR: [DMA Write] Request device [04:00.0] PASID ffffffff fault addr 69974000 [fault reason 05] PTE Write access is not set The reason is unknown and hard to debug because we were not able to reproduce this locally. This only happens on certain systems with Intel Maple Ridge Thunderbolt controller. If there is a device connected when the driver is loaded the issue does not happen either. Only when there is nothing connected (so typically when the system is booted up). We can work this around by sending the driver ready several times. After a couple of retries the message goes through and the controller works just fine. For this reason make the number of retries a parameter for icm_request() and then for Maple Ridge (and Titan Ridge as they us the same function but this should not matter) increase number of retries while shortening the timeout accordingly. Reported-by: Werner Sembach <wse@tuxedocomputers.com> Reported-by: Konrad J Hambrick <kjhambrick@gmail.com> Reported-by: Calvin Walton <calvin.walton@kepstin.ca> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=214259 Cc: stable@vger.kernel.org Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.