Re: What is the reason to...

[Jonathan Larmour <jifl@eCosCentric.com>]

Bart Veer wrote:
>>>>>> "Oliver" == oliver munz @ s p e a g <munz@speag.ch> writes:
> 
>     Oliver> mark CYGPKG_IO_SPI as HARDWARE?
>     Oliver> I think Generic SPI or I2C and so one should be loadable
>     Oliver> whitout an template. Can we change this?
> 
> The problem here is that other drivers such as the wallclock or
> dataflash are likely to depend on the SPI/I2C bus being available. On
> some platforms there may even be platform HAL dependencies on the bus.
> Now, by convention you can enable flash support on a given platform
> simply by e.g. "ecosconfig add flash" and everything sorts itself out.
> If the SPI or I2C bus driver was not automatically part of the
> configuration then that would stop working.
> 
> If you want the SPI or I2C support to be automatically available when
> needed, working within the limitations of current CDL, then the
> generic SPI or I2C packages have to be part of the target definition
> in ecos.db. That means they have to be hardware packages.

I've said this before and will just take the opportunity to say it again:
the 'hardware' attribute just gets in the way. You can't have packages in
the target definition that aren't 'hardware', and you can't add packages
which are marked as 'hardware', so there is a wholly artificial division
between packages.

I would prefer the whole 'hardware' attribute was dropped and give platform
developers, and application developers the ability to control their own
hardware configuration without having to edit repository files. It should
be possible for the HAL developers to list any driver packages appropriate
for their hardware in the target definition; and possible for app
developers to add/remove from that as needed. There's always been plug-in
modules, expansion buses etc., nevermind modern configurable hardware, so
assuming hardware is static seems archaic.

I suspect it has cost people more wasted time and confusion than it has
ever saved. I've had to jump through these hoops, and not seen any benefit.

Jifl
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