Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
ResourceTemplate ()
{
// List of resource macros
}
The following is an example of how these macros can be used to create a resource template that can
be returned from a _PRS control method:
Name (PRS0, ResourceTemplate ()
{
StartDependentFn (1, 1)
{
IRQ (Level, ActiveLow, Shared) {10, 11}
DMA (TypeF, NotBusMaster, Transfer16) {4}
IO (Decode16, 0x1000, 0x2000, 0, 0x100)
IO (Decode16, 0x5000, 0x6000, 0, 0x100, IO1)
}
StartDependentFn (1, 1)
{
IRQ (Level, ActiveLow, Shared) {}
DMA (TypeF, NotBusMaster, Transfer16){5}
IO (Decode16, 0x3000, 0x4000, 0, 0x100)
IO (Decode16, 0x5000, 0x6000, 0, 0x100, IO2)
}
EndDependentFn ()
})
Occasionally, it is necessary to change a parameter of a descriptor in an existing resource template at
run-time (i.e., during a method execution.) To facilitate this, the descriptor macros optionally
include a name declaration that can be used later to refer to the descriptor. When a name is declared
with a descriptor, the ASL compiler will automatically create field names under the given name to
refer to individual fields in the descriptor.
The offset returned by a reference to a resource descriptor field name is either in units of bytes (for
8-, 16-, 32-, and 64-bit field widths) or in bits (for all other field widths). In all cases, the returned
offset is the integer offset (in either bytes or bits) of the name from the first byte (offset 0) of the
parent resource template.
For example, given the above resource template, the following code changes the minimum and
maximum addresses for the I/O descriptor named IO2:
CreateWordField (PRS0, IO2._MIN, IMIN)
Store (0xA000, IMIN)
CreateWordField (PRS0, IO2._MAX, IMAX)
Store (0xB000, IMAX)
The resource template macros for each of the resource descriptors are listed below, after the table
that defines the resource descriptor. The resource template macros are formally defined in
Section 6.4.1, “ASL Macros for Resource Descriptors.”
The reserved names (such as _MIN and _MAX) for the fields of each resource descriptor are defined
in the appropriate table entry of the table that defines that resource descriptor.
788 April, 2015 Version 6.0