[wiki:Component SocLib Components General Index] 

= MicroBlaze Processor Functional Description =

This hardware component is a MicroBlaze processor core as described in [www.xilinx.com/ise/embedded/mb_ref_guide.pdf the Xilinx documentation].
Note that the 9.2 version of ISE contains a pretty major evolution of the MicroBlaze that integrates a MMU, but this is not the version available within SoCLib (at least yet!).
This component is an ISS, which should be wrapped with an [wiki:Component/IssWrapper IssWrapper] for integration into a complete platform.

This instruction set simulator acts as a slave to the IssWrapper and is organised identically to the
other Isses available within the library.
Currently, the execution timings are pretty rough, and are typically one cycle per instruction.

The support for symetric and asymetric multiprocessing is hardwired using the `fsl` feature of the MicroBlaze.
The processor number is given at instanciation time, and accessible through `get` on `fsl0`.
Using other `fsl`s will lead to an abort.

= Component definition =

Available in source:trunk/soclib/soclib/lib/metadata/microblaze.sd

== Usage ==

MicroBlaze has no parameters.
{{{
Uses( 'microblaze')
}}}

= Microblaze Processor ISS  Implementation =

The implementation is in 
 * source:trunk/soclib/soclib/lib/src/iss/microblaze.h
   This defines the resources associated to the MicroBlaze along with a few
   minimal helper functions (or methods, as they call them)
 * source:trunk/soclib/soclib/lib/src/iss/microblaze.cpp
   This is a large switch (as opposed to calling insn execution through
   pointers to functions) and a few macros, as it is overall not worse to
   traverse a switch than to move from tag to tag, seen the context necessary
   to the execution of one instruction (at least in the MicroBlaze case).

It is possible to compile a version of the MicroBlaze that issues the instruction
address along with the instruction being executed by defining `MBDEBUG` at `1` line
35 of source:trunk/soclib/soclib/lib/src/iss/microblaze.cpp
This is quite useful to check that the processor is really interpreting correctly a
sequence of instructions.
The MicroBlaze model is now able to connect to the GDB stub, so it is possible to
use GDB for debugging software running on it.

== Template parameters ==
 
This component has no template parameters.

== Constructor parameters ==

{{{
MicroblazeIss( 
     sc_module_name name,   //  Instance Name
     int  ident);   // processor id
}}}

== Visible registers ==

I'm not sure to understand what this means, ...

== Interrupts ==

There is a single interrupt line on the MicroBlaze, so all the handling is
software based.

== Ports ==

None, They are provided by the `IssWrapper`.