
Advanced Boot Techniques
16-32
ADSP-BF59x Blackfin Processor Hardware Reference
load function requires access to the block's
ARGUMENT
word, it should be
read early in the function.
The most useful load functions
BFROM_MDMA
and
BFROM_PDMA
are accessible
through the jump table. Others, do not have entries in the jump table.
Their start address can be determined with the help of the hook routine
when calling the respective
BFROM_SPIBOOT
or other functions. In this way,
they can be re-purposed for runtime utilization.
Calling the Boot Kernel at Runtime
The boot kernel’s primary purpose is to boot data to memory after
power-up and reset cycles. However some of the routines used by the boot
kernel might be of general value to the application. The boot ROM sup-
ports reuse of these routines as C-callable subroutines. Programs such as
second-stage boot kernels, boot managers, and firmware update tools may
call the function in the ROM at runtime. This could load entirely differ-
ent applications or a fraction of an application, such as a code overlay or a
coefficient array.
To call these boot kernel subroutines, the boot ROM provides an API at
address 0xEF00 0000 in the form of a jump table.
When calling functions in the boot ROM, the user must ensure the pres-
ence of a valid stack following C language conventions. See the
Vi+ Compiler documentation for details.
Debugging the Boot Process
If the boot process fails, very little information can be gained by watching
the chip from outside. In master boot modes, the interface signals can be
observed. In slave boot modes only the
HWAIT
or the
RTS
signals tell about
the progress of the boot process.
However, by using the emulator, there are many possibilities for debug-
ging the boot process. The entire source code of the boot kernel is
Содержание ADSP-BF59x Blackfin
Страница 64: ...Development Tools 1 22 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 74: ...Processor Specific MMRs 2 10 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 204: ...Unique Information for the ADSP BF59x Processor 5 104 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 244: ...Programming Examples 6 40 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 345: ...ADSP BF59x Blackfin Processor Hardware Reference 9 9 Core Timer Unique Information for the ADSP BF59x Processor None...
Страница 346: ...Unique Information for the ADSP BF59x Processor 9 10 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 398: ...Unique Information for the ADSP BF59x Processor 11 42 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 622: ...Unique Information for the ADSP BF59x Processor 15 38 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 700: ...Programming Examples 16 78 ADSP BF59x Blackfin Processor Hardware Reference...
Страница 738: ...Boundary Scan Architecture B 8 ADSP BF59x Blackfin Processor Hardware Reference...