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64adde31c8
Currently, there is only a 1 ms sleep after asserting PERST.
Reading the datasheets for different endpoints, some require PERST to be
asserted for 10 ms in order for the endpoint to perform a reset, others
require it to be asserted for 50 ms.
Several SoCs using this driver uses PCIe Mini Card, where we don't know
what endpoint will be plugged in.
The PCI Express Card Electromechanical Specification r2.0, section
2.2, "PERST# Signal" specifies:
"On power up, the deassertion of PERST# is delayed 100 ms (TPVPERL) from
the power rails achieving specified operating limits."
Add a sleep of 100 ms before deasserting PERST, in order to ensure that
we are compliant with the spec.
Fixes: 82a823833f ("PCI: qcom: Add Qualcomm PCIe controller driver")
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Cc: stable@vger.kernel.org # 4.5+
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
``make pdfdocs``. The formatted documentation can also be read online at:
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.