SMART Embedded Computing COMX-P2020 BSP, Installation And Use Manual

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Functional Description
COMX-P2020 Module Installation and Use (6806800K97F) 77
U-boot will use the following parameters to initialize the UARTs:
4.12 USB
P2020 implements a dual-role (DR) USB module. This module is connected to USB2514i
which can provide 4 downstream ports. The DR module can act as a device or host
controller, while in this case, it is configured as a host controller, and it can support at most
six bidirectional USB endpoints.
4.13 PCI Express
There are three PCI Express on COMX-P2020. The PCI Express are configured as:
 PCI Express 1 x1 (2.5 Gbps) SerDes lane 0
 PCI Express 2 x1 (2.5 Gbps) > SerDes lane 1
 PCI Express 3 x2 (2.5 Gbps) SerDes lanes 2-3
 PCI Express 1 is connected to GPU Z11M. The other two are connected to the
carrier board
Table 4-2 Initialization Parameters
Parameter Value
Baud rate 115200
Data bit 8
Parity None
Stop bit 1
CCB Clock 400 MHz
Divisor most and least significant byte registers CCB Clock / Baud rate / 16 = 326
Internal interrupt number 26