Re: [PATCH v2 0/7] ARM: Broadcom Brahma-B15 readahead cache support

[Florian Fainelli]

On 08/14/2017 09:23 AM, Florian Fainelli wrote:
> 
> 
> On 07/14/2017 03:11 PM, Florian Fainelli wrote:
>> On 06/23/2017 10:52 AM, Florian Fainelli wrote:
>>> Hi all,
>>>
>>> This patch series adds support for the Broadcom Brahma-B15 readahead cache.
>>> I submitted that patch series a couple of years ago, and then slept on it so
>>> here is another stab at it.
>>>
>>> Note that we did not implement this cache as a version of an outer cache
>>> for several reasons:
>>>
>>> - we initially thought we needed to intercept flush_icache_all and
>>>   flush_kern_cache_louis but upon further inspection we convinced ourselves
>>>   this is no longer needed, still, flush_cache_all() needs special handling
>>>   here and needs to be wrapped around
>>>
>>> - the outer cache does not allow differentiating a DMA transfer direction
>>>   this is a readahead cache, so it does not participate in writes, flushing
>>>   it during reads *and* writes kills the performance completely
>>>
>>> - finally, most operations that outer_cache cares about are on MVA, which
>>>   is transparent to the readahead cache here
>>>
>>> Changes in v2:
>>>
>>> - clarify that the read-ahead caches does invalidates on writes (IOW) based
>>>   on Russell's feedback
>>
>> Any comments on this? Thank you.
> 
> Should I just go a ahead and queue these changes in Russell's patch tracker?

Per IRC conversation with Russell, queued into his patch tracking system as:

http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8724/1
http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8725/1
http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8729/1
http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8726/1
http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8730/1
http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8728/1
http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8727/1
-- 
Florian