Specifying specific CPU models in powerpc/qoriq BSPs

Travis Wheatley travis.wheatley at emergentspace.com
Tue Mar 15 17:32:58 UTC 2016

I am working with a powerpc development board. RTEMS 4.12 has an existing BSP configuration that is very similar to what I am looking for. However, my development board uses a different processor/core, and therefore I presume will need a different a different set of libcpu files. I have read several documents including Chapter 3 of the RTEMS On-Line library files and understand that the Makefile.am, Makefile.in, and configure.ac files are used by bootstrap to generate the bsp configuration. Additionally, I understand that there is a .cfg file found in the make/custom directory associated with the BSP in which one specifies items like RTEMS_CPU_MODEL. In the case of this BSP here is what I find in the existing .cfg file:

--- Begin included text ---

include $(RTEMS_ROOT)/make/custom/default.cfg

RTEMS_CPU = powerpc


CPU_CFLAGS = -mcpu=e6500 -m32 -msdata=sysv -fno-common \

CFLAGS_OPTIMIZE_V += -ffunction-sections -fdata-sections

LDFLAGS = -Wl,--gc-sections

--- end included text ---

Where I am confused is that the RTEMS_CPU_MODEL is listed as "qoriq". However, under the lib/cpu/powerpc directory I see processor specific code for multiple powerpc processors including both mpc5xx and mpc6xx specific items So my question is this...

While I see that the CPU_CFLAGS variable in the above .cfg file contains a flag that tells the compiler to build code for the e6500, I do not see any flag that tells bootstrap or the resulting build files produced to use the mpc6xx libcpu items. So, if I want to build a similar BSP configuration but for a development board using an mpc5xx processor, exactly where do I specify that in the various make and configuration files? 

-- Travis Wheatley

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