[Boost-users] hardware bit set, clr, tst templates

From: Perry Smith (pedz_at_[hidden])
Date: 2006-02-16 13:43:55

Before I jump off and re-invent the wheel -- is there a boost library  
to help with manipulating hardware registers?

What I'm hoping to come up with (somehow) is something like:

class dev_registers {
   reg<uint32_t> reg0;
   bit<reg0, 0> b0;
   bit<reg0, 1> b1;

   reg<uint32_t> reg1;
   bit<reg1, 0> b3;
   bit<reg1, 1> b4;
};

(The 0 and 1 are bit offsets.  Integer masks like 0x0010 would work  
as well)

The result would be a private members of type uint32_t called reg0,  
and reg1 (actually they can be called anything since they are  
private).  And a set of public methods to set, clear, and test the  
bits. e.g.

dev_registers sample;

sample.b0.set();
sample.b3.clr();

It would be nice if the registers had a global clr like:

sample.reg0.clr();

There are lots of alternative approaches like:

sample.b0.assign(true);  // set b0 to true (1)
int val = sample.b0();  // test value of b0

The goal has a lot of constraints.  The registers would need to be  
laid out properly without any extra overhead (assuming that I do not  
bump into normal C padding problems).  It would also be nice if  
everything inline'd so the compiler could optimize things down to  
simple bit operations.

Does boost have anything like that?  I looked for "bit" and only  
found references to bitset.  I also looked for "hardware" and "flag"  
and did not see anything.

Thanks,
Perry