Re: [ECOS] Redboot driver vs eCos driver

[Jonathan Larmour <jlarmour at redhat dot com>]

Fabrice Gautier wrote:
> 
> Hi,
> 
> It appears that there is some ide driver and ext2fs driver in Redboot (for
> x86) that allows you to load a file from a cd or a ext2 partition. it
> doesn't seem those driver could be used in eCos. I am wrong and if not what
> do you think it would take to be able to integrate that as an eCos driver ?

We had discussions about this internally. One noticeable omission in eCos
that would be a prerequisite is a proper block device layer, allowing for
interrupt driven I/O. The RedBoot driver doesn't need or want interrupt
driven I/O - too much overhead, although a decently written layer would
hopefully avoid be able to configurably avoid that.

After that of course you want to integrate such an FS into the io/fileio
framework, and doing that in a purely polled way, and read-only, is much
much easier than read-write and allowing overlapping I/O operations and the
possibility of DMA.

But anyway, the first stage would be the block device layer. Nick, I
believe that you may have some opinions on this?

Jifl
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