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Date: Sun, 24 Jul 2011 13:56:00 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH 1/7] Export the unassigned_mem read/write
 functions.
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To: Richard Henderson <rth@twiddle.net>
Cc: qemu-devel@nongnu.org

On 07/24/2011 11:42 AM, Richard Henderson wrote:
> On 07/24/2011 06:28 AM, Anthony Liguori wrote:
>> On 07/23/2011 02:17 PM, Richard Henderson wrote:
>>> Signed-off-by: Richard Henderson<rth@twiddle.net>
>>
>> Why?
>
> So that I can write i/o functions like this:
>
>    switch (addr) {
>    case 0: ...
>    case 64: ...
>    case 128: ...
>    ...
>    default:
>      unassigned_mem_readl(...)
>    }
>
> Perhaps Avi's rewrite makes this unnecessary; I browsed through
> his patch set but didn't immediately see if there's a way for
> the i/o function to return "failure".

What is returned by totally unregistered MMIO is defined by the chipset. 
  What's returned by an empty space in the MMIO space of a device is 
device specific.

What does your device return if there's an access at 32?

Regards,

Anthony Liguori

>
> What I certainly don't want to do is write this with 100 tiny
> functions registering 8 bytes each, registered some tiny
> distance away from each other.
>
>
> r~
>