Re: [ECOS] structure XScale HAL ?

[Mark Salter <msalter at redhat dot com>]

>>>>> david  writes:

> Hello,
> I was wondering if anybody else has been using the xscale HAL for a port other
> than the IQ-80321 ?
> Or has this been a one-off implementation for the IQ-80321 ?
> As I am currently doing a port to a pxa-250 based board, I have been dissecting
> the xscale tree a bit, and I think that the current structure of the xscale
> tree needs some rearranging, so I would appreciate some feedback on the following:

> Currently, CYGPKG_HAL_ARM_XSCALE_IQ80321 has CYGPKG_HAL_ARM_XSCALE_CORE as its
> parent. But the IQ-80321 is a board based on the IOP321 cpu, which in turn has
> an XScale core.
> Similarly, the port I am doing is for a board based on the PXA250 cpu, which also has an XScale core.
> So, to have a clean port, I think it would be best to have a 3-level
> structure instead of the current 2-level structure:
> - XSCALE_CORE (with core specific stuff)
> - XSCALE_PXA250 (with cpu specific stuff)
> - XSCALE_my_board (with board specific stuff)

> With the current 2-level structure of the IQ-80321 port, the cpu-support
> for the IOP321 gets mixed with the board-support for the IQ-80321, which also
> means that the IOP321 specific stuff cannot be easily used for other ports
> with that same cpu.
> I think it would also be nice to have separate directories in the tree for
> this (e.g. xscale/core , xscale/cpu, xscale/board).

> But before starting with that structure for my port, I would like to know what
> anybody else is doing. 
> (If it's a daft idea, I will also stick to the 2-level structure ;-)

The current structure is 3-level. Look a little closer and you'll see that
the iq80321 port uses:

  hal/arm/xscale/cores    -- XScale core
  hal/arm/xscale/verde    -- IOP321 CPU
  hal/arm/xscale/iq80321  -- board

It probably could use some CDL tweaks and possibly some code partitioning
tweaks, but the basic structure you desire is there.

--Mark

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