[PATCH 1/4] ucc_geth: Change private immrbar_virt_to_phys to generic iopa

[Kumar Gala]

On Feb 8, 2007, at 1:36 AM, Li Yang-r58472 wrote:

>> -----Original Message-----
>> From: Kumar Gala [mailto:galak at kernel.crashing.org]
>> Sent: Thursday, February 08, 2007 3:16 PM
>> To: Li Yang-r58472
>> Cc: Tabi Timur-B04825; netdev at vger.kernel.org; linuxppc- 
>> dev at ozlabs.org
>> Subject: Re: [PATCH 1/4] ucc_geth: Change private  
>> immrbar_virt_to_phys
> to generic
>> iopa
>>
>>
>> On Feb 8, 2007, at 1:06 AM, Li Yang-r58472 wrote:
>>
>>>>> MURAM is a mmio region so it don't share the characteristic of
> main
>>>>> memory that phy_addr = virt_addr - PAGE_OFFSET.  While they can
>>>>> both be
>>>>> mapped through page table using iopa().
>>>>
>>>> Right, so when do you know if you'll be using MURAM or normal
>>>> memory?  Why not just keep around a token that is the physical
>>>> address at the point you make the decision of MURAM vs normal
> memory.
>>>
>>> Yes, that can be a way.  But as the virt to phy mapping is only used
>>> once, it's nothing bad to do it this way.
>>
>> The problem as I stated before with using iopa() is that its not
>> supported across platforms.
>
> Yes, it is only for PPC32.  But we don't have another API to do  
> it.  How
> about make it more generic to add PPC64 version?

Why do you need another API to do this, you already have the  
information you want, its just a matter of you keeping track of it.

- k