Analog Devices ADSP-BF506F Hardware Reference Manual page 1135

3. After the callback routine returns, the memory DMA copies data to
the destination.
If a block does not fit into the temporary buffer, for example when the
is greater than the
BLOCK COUNT
are executed multiple times until all payload data is loaded and processed.
The boot kernel passes the parameter
tell it that it is being invoked the first or the last time for a specific block.
To store intermediate results across multiple calls the callback routine can
use the
uwUserShort
structure.
Callback routines meet C language calling conventions for subroutines.
The prototype is as follows.
s32 CallBackFunction (ADI_BOOT_DATA* pBootStruct,
ADI_BOOT_BUFFER* pCallbackStruct, s32 dCbFlags);
The header file defines the
way:
typedef s32 ADI_BOOT_CALLBACK_FUNC (ADI_BOOT_DATA*,
ADI_BOOT_BUFFER*, s32 ) ;
The
pBootStruct
ADI_BOOT_DATA
the
pTempBuffer
pointer to the
further by modifying the
The
pCallbackStruct
length of the data buffer. When the
pCallbackStruct
block. If the
BFLAG_INDIRECT
copy of the
pTempBuffer
processing progress, the byte count provided by
either
dTempByteCount
ADSP-BF50x Blackfin Processor Hardware Reference
dTempByteCount
and
dUserLong
ADI_BOOT_CALLBACK_FUNC
argument is passed in
structure used by the boot kernel. These are handled by
and
dTempByteCount
field. The callback routine may process the block
ARGUMENT
pTempBuffer
structure passed in
contains the target address and byte count of the boot
flag is set, the
. Depending on the size of the boot block and
or the remainder of the byte count.
System Reset and Booting
variable, the three steps
to the callback routine to
dCbFlags
variables in the
ADI_BOOT_DATA
type the following
and points to the
R0
variables as well as the
and
dTempByteCount
provides the address and
R1
flag is not set, the
BFLAG_INDIRECT
pCallbackStruct
pCallbackStruct
pHeader
variables.
contains a
equals
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