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377bced88c
Add a bare minimum amount of changes in order to support PCIe Root Complex hardware IP found on RPi5. The PCIe controller on BCM2712 is based on BCM7712 and as such it inherits register offsets, PERST# assertion, bridge_reset ops, and inbound windows count. Although, the implementation for BCM2712 needs a workaround related to the control of the bridge_reset where turning off of the Root Port must not shutdown the bridge_reset and this must be avoided. To implement this workaround a quirks field is introduced in pcie_cfg_data struct. The controller also needs adjustment of PHY PLL setup to use a 54MHz input refclk. The default input reference clock for the PHY PLL is 100Mhz, except for some devices where it is 54Mhz like BCM2712C1 and BCM2712D0. To implement those adjustments introduce a new .post_setup op in pcie_cfg_data and call it at the end of brcm_pcie_setup function. The BCM2712 .post_setup callback implements the required MDIO writes that switch the PLL refclk and also change PHY PM clock period. Without this RPi5 PCIex1 is unable to enumerate endpoint devices on the expansion connector. Signed-off-by: Stanimir Varbanov <svarbanov@suse.de> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Reviewed-by: Jim Quinlan <james.quinlan@broadcom.com> Tested-by: Ivan T. Ivanov <iivanov@suse.de> Link: https://lore.kernel.org/r/20250224083559.47645-8-svarbanov@suse.de [commit log] Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.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
``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 reStructuredText 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.