[ECOS] Question: Banked FLASH

[ECOS] Question: Banked FLASH

[Sergei Gavrikov]

Hello,

Does exist a way (like FLASH_P2V macro) to manage flash banking using
_generic_PIO_? I have 1 part of the solid 2M Intel 28fxxx flash, but I
cannot use A20 line in a address mode. That line is a generic PIO line.
Should I copy a generic 28fxxx driver code in my hal/devs/flash and
tweak that source or there is more elegant way in eCos flash devices
world?

Thanks anyone,

Sergei


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Re: [ECOS] Question: Banked FLASH

[Andrew Lunn]

On Fri, Jun 08, 2007 at 04:51:23PM +0300, Sergei Gavrikov wrote:
> Hello,
> 
> Does exist a way (like FLASH_P2V macro) to manage flash banking using
> _generic_PIO_? I have 1 part of the solid 2M Intel 28fxxx flash, but I
> cannot use A20 line in a address mode. That line is a generic PIO line.
> Should I copy a generic 28fxxx driver code in my hal/devs/flash and
> tweak that source or there is more elegant way in eCos flash devices
> world?

There is no existing solution to this that i know of.

The flash_v2 branch has some interesting possibilities. It supports
multiple flash drivers in a flexible way. It also supports a form of
virtual addresses. So with the V2 branch you could have the 28fxxx
driver at the physical address of the flash, and it would drive which
ever bank is currently mapped in. On top of that you have a virtual
driver which implements the full 2M address range but at a different
address. It would set the GPIO line as appropriate and then pass
requests onto the physical driver, mapping the addresses as
appropriate.

If you do decide to implement this, it would be great to have it
contributed back. It should be possible to make the virtual driver
generic with a hardware specific package which implements the bank
manipulation function. I can help with the design and testing. It is
something i thought about doing a while ago, but never got around to.

          Andrew

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Re: [ECOS] Question: Banked FLASH

[Sergei Gavrikov]

Andrew,

Thank you! I appreciate your underlying ideas. I will try to finalize
that issue.

Sergei


Andrew Lunn wrote:
> On Fri, Jun 08, 2007 at 04:51:23PM +0300, Sergei Gavrikov wrote:
> > Hello,
> > 
> > Does exist a way (like FLASH_P2V macro) to manage flash banking using
> > _generic_PIO_? I have 1 part of the solid 2M Intel 28fxxx flash, but I
> > cannot use A20 line in a address mode. That line is a generic PIO line.
> > Should I copy a generic 28fxxx driver code in my hal/devs/flash and
> > tweak that source or there is more elegant way in eCos flash devices
> > world?
> 
> There is no existing solution to this that i know of.
> 
> The flash_v2 branch has some interesting possibilities. It supports
> multiple flash drivers in a flexible way. It also supports a form of
> virtual addresses. So with the V2 branch you could have the 28fxxx
> driver at the physical address of the flash, and it would drive which
> ever bank is currently mapped in. On top of that you have a virtual
> driver which implements the full 2M address range but at a different
> address. It would set the GPIO line as appropriate and then pass
> requests onto the physical driver, mapping the addresses as
> appropriate.
> 
> If you do decide to implement this, it would be great to have it
> contributed back. It should be possible to make the virtual driver
> generic with a hardware specific package which implements the bank
> manipulation function. I can help with the design and testing. It is
> something i thought about doing a while ago, but never got around to.
> 
>           Andrew


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Re: [ECOS] Question: Banked FLASH

[Sergei Gavrikov]

Andrew Lunn wrote:
> On Fri, Jun 08, 2007 at 04:51:23PM +0300, Sergei Gavrikov wrote:
> > Hello,
> > 
> > Does exist a way (like FLASH_P2V macro) to manage flash banking using
> > _generic_PIO_? I have 1 part of the solid 2M Intel 28fxxx flash, but I
> > cannot use A20 line in a address mode. That line is a generic PIO line.
> > Should I copy a generic 28fxxx driver code in my hal/devs/flash and
> > tweak that source or there is more elegant way in eCos flash devices
> > world?
> 
> There is no existing solution to this that i know of.
> 
> The flash_v2 branch has some interesting possibilities. It supports
> multiple flash drivers in a flexible way. It also supports a form of
> virtual addresses. So with the V2 branch you could have the 28fxxx
> driver at the physical address of the flash, and it would drive which

Andrew,

I am a bit confused about a joining 'flash_v2' branch with the latest
anon CVS tree. When I do

cvs -z3 up -j flash_v2 io/flash
...

I get the reports about collisions, and if I use 'flash_v2' 

cvs -z3 up -r flash_v2 io/flash
...

it seems for me that I fullfil some downgrades against anon CVS sources.
Should that occur? Where am I wrong? It's possible I have to specify
some DATE mark with 'tag. Please, tip me how to merge 'flash_v2' branch
with latest sources properly? Thank you.

Kind regards,

-- Sergei


> ever bank is currently mapped in. On top of that you have a virtual
> driver which implements the full 2M address range but at a different
> address. It would set the GPIO line as appropriate and then pass
> requests onto the physical driver, mapping the addresses as
> appropriate.
> 
> If you do decide to implement this, it would be great to have it
> contributed back. It should be possible to make the virtual driver
> generic with a hardware specific package which implements the bank
> manipulation function. I can help with the design and testing. It is
> something i thought about doing a while ago, but never got around to.
> 
>           Andrew


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