Area Group Constraint - 2021.2 English

Versal ACAP AI Engine Programming Environment User Guide (UG1076)

Document ID
UG1076
Release Date
2021-12-17
Version
2021.2 English

The area group constraint specifies a range of tile and/or shim locations to which a group of one or more nodes can be mapped. The area group constraint can be specified with the following properties.

groups
Specify the collection of groups. The groups can be:
tile-type
Specify the tile-type for the group. Supported tile-types are aie_tile, shim_tile, or memory_tile.
column_min
Column index for lower left corner of the group.
row_min
Row index for lower left corner of the group.
column_max
Column index for upper right corner of the group.
row_max
Row index for upper right corner of the group.
contain_routing
A boolean value that when specified true ensures all routing, including nets between nodes contained in the nodeGroup, is contained within the area group.
exclude_routing
A boolean value that when specified true ensures all routing, excluding nets between nodes from the nodeGroup, is excluded from the area Group.
exclude_placement
A boolean value that when specified true prevents all nodes not included in nodeGroup from being placed within the area group bounding box.

An AI Engine tile or memory tile range is in the form of (column, row):(column, row), where the first tile is the bottom left corner and the second tile the upper right corner. The column and row values are zero based, where the zeroth row is counted from the bottom-most compute processor and the zeroth column is counted from the left-most column.

A shim range is in the form of (column):(column), where the first value is the left-most column and the second value the right-most column. The column is zero based, where the zeroth row is counted from the bottom-most compute processor and the zeroth column is counted from the left-most column. The shim range also allows an optional channel to be specified, for example, (column, channel):(column, channel).

The area group is used to exclude a range on the device from being used by the compiler for mapping and optionally routing as follows.

  • To exclude a range from router, set nodeGroup and set exclude_placement to true.
  • To exclude a range from mapper, set nodeGroup and set exclude_routing to true.
  • To include all nets within a nodeGroup for router and mapper, set nodeGroup and set contain_routing to true.
Note: There can be any number of area group constraints in the Global Constraints section, as long as each constraint has a unique name.

Syntax

"areaGroup": {
  "name": string,

  "nodeGroup": [<node list>], (*optional)
  "tileGroup": [<tile list>], (*optional)
  "shimGroup": [<shim list>], (*optional)
  "contain_routing": bool, (*optional)
  "exclude_routing": bool, (*optional)
  "exclude_placement"" bool, (*optional)
}

<node list> ::= <node name>[,<node name>...]

<tile array> ::= <tile value>[,<tile value>...]
<tile value> ::= <tile range> | <tile address>
<tile range> ::= "<tile address>[:<tile address>]"
<tile address> ::= (<column>, <row>)

<shim array> ::= <shim value>[,<shim value>...]
<shim value> ::= <shim range> | <shim address>
<shim range> ::= "<shim address>[:<shim address>]"
<shim address> ::= (<column>[,<channel>])

<node name> ::= string
<column> ::= integer
<row> ::= integer
<channel> ::= integer

Example

{
  "GlobalConstraints": {
    "areaGroup": {
      "name": "mygraph_area_group",
      "nodeGroup": ["mygraph.k1", "mygraph.k2"],
      "tileGroup": ["(2,0):(2,3)"],
      "shimGroup": ["0:3"]
    }
  }
}

Example of Exclude

{
  "GlobalConstraints": {
    "areaGroup": {
      "name": "mygraph_excluded_area_group",

      "tileGroup": ["(3,0):(4,3)"],
      "shimGroup": ["3:4"],
      "exclude_routing": true
    }
  }
}