The M2 Ultra in the Mac Pro differs from the M2 Ultra Mac Studio in its
PCIe setup. It uses all available 16 PCIe Gen4 on the first die and 8
PCIe Gen4 lanes on the second die to connect to a 100 lane Microchip
Switchtec PCIe switch. All internal PCIe devices and the PCIe slots are
connected to the PCIe switch.
Each die implements a PCIe controller with a single 16 or 8 lane port.
The PCIe controller is mostly compatible with existing implementation
in pcie-apple.c.
The resources for other 8 lanes on the second die are used to connect
the NVMe flash with the controller in the SoC.
This initial device tree does not include PCIe support.
Signed-off-by: Hector Martin <marcan@marcan.st> Reviewed-by: Neal Gompa <neal@gompa.dev> Co-developed-by: Janne Grunau <j@jannau.net> Signed-off-by: Janne Grunau <j@jannau.net> Reviewed-by: Sven Peter <sven@kernel.org> Signed-off-by: Sven Peter <sven@kernel.org>