P4080 PCIe Adapter SDK User Guide Production Release

Freescale Semiconductor
qportal1: qman-portal@4000 {
cell-index = ;
compatible = "fsl,p4080-qman-portal", "fsl,qman-portal";
fsl,usdpaa-portal;
reg = ;
cpu-handle = ;
interrupts = ;
fsl,qman-channel-id = ;
fsl,qman-pool-channels = ;
};
There is no mechanism provided to determine what, if anything, user space software will do with a given
user space portal. Initially, these portals are present but not initialized. Each user space portal has a /dev
entry. It is a USDPAA driver decision as to which portals a given process or thread will use. A portal is
placed into use when a user space process or thread requests it via the QMan API.
4.8 Note on the current USDPAA Implementation
In the current implementation, portals are bound to cores via the cpu-handle in the portal device tree node.
Most commonly, a thread will make itself affine to its portal’s core. If it does not, stashing may be done
to the wrong core’s cache. This is not necessarily functionally incorrect, but it is not efficient.
4.9 Buffer Manager (BMan)
The BMan driver and its software support is very similar to QMan’s. BMan software portals may be used
in the kernel or in user space just like QMan portals. Just as with QMan, the same BMan software API is
available in both the kernel and in user space. This API also is defined in the “Queue Manager, Buffer
Manager API Reference Manual.”
4.10 DMA-Memory Management
The Freescale DPAA hardware provides several peripherals such as FMan, SEC, and PME that read and
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