From mboxrd@z Thu Jan  1 00:00:00 1970
From: iamjoonsoo.kim@lge.com (Joonsoo Kim)
Date: Wed, 8 Nov 2017 16:46:45 +0900
Subject: n900 in next-20170901
In-Reply-To: <20171107154842.GP28152@atomide.com>
References: <20171018082927.GB27595@js1304-P5Q-DELUXE>
 <20171019183033.GH4394@atomide.com>
 <20171020015542.GA10438@js1304-P5Q-DELUXE>
 <20171020173146.GN4394@atomide.com>
 <20171023045342.GA23082@js1304-P5Q-DELUXE>
 <20171025173137.GQ4394@atomide.com>
 <20171026044829.GB11791@js1304-P5Q-DELUXE>
 <20171026141627.GD21504@atomide.com>
 <20171107053313.GA12447@js1304-P5Q-DELUXE>
 <20171107154842.GP28152@atomide.com>
Message-ID: <20171108074645.GA18747@js1304-P5Q-DELUXE>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Tue, Nov 07, 2017 at 07:48:42AM -0800, Tony Lindgren wrote:
> Hi,
> 
> * Joonsoo Kim <iamjoonsoo.kim@lge.com> [171107 05:30]:
> > Could you test follwing updated branch?
> > 
> > https://github.com/JoonsooKim/linux/tree/cma-debug4-next-20180901
> > 
> > It has three relevant commits on top and enables CMA memory use.
> 
> Okie dokie.
> 
> > "arm/dma: remove i-cache flush"
> 
> Your branch at the above commit is not booting on n900.
> 
> > "arm/dma: flush i-cache and d-cache separately"
> 
> Not booting at this commit either.
> 
> > "arm/dma: call flush_cache_all() and don't do outer cache operation"
> 
> Not booting at this commit either.
> 
> Earlier commit f14f3479c0d7 ("arm/dma: re-enable to remap the CMA
> area and flush cache before remapping") in you branch boots.
> 
> Then the following commit d6512d6d0171 ("Revert "arm/mm: disable
> atomic_pool"") won't boot.
> 
> Also your tree at commit 6d0525cef962 ("arm/dma: remove i-cache
> flush") with only commit d6512d6d0171 ("Revert "arm/mm: disable
> atomic_pool"") reverted boots on n900.

Thanks a lot!

> So it seems the issue is currently at the atomic_pool_init()
> related code?

Yes, your test showed it although I can't find any clue in
atomic_pool_init().

Could you test updated branch?

https://github.com/JoonsooKim/linux/tree/cma-debug4-next-20180901

There are two relevant commits.

arm/dma: stop dma allocation before __dma_alloc_remap()
arm/dma: disable atomic pool after dma allocation

atomic pool initialization will be done partially to check
exact point of failure. These are brain-dead commits however I have no
idea what's going on here until now. :/

Thanks.