Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Heiko Stuebner <heiko@sntech.de>
To:     Johan Jonker <jbx6244@gmail.com>, John Keeping <john@metanate.com>
Cc:     dri-devel@lists.freedesktop.org, Sandy Huang <hjc@rock-chips.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org
Subject: Re: [BUG] [PATCH] drm/rockchip: use generic fbdev setup
Date:   Mon, 17 Oct 2022 13:29:11 +0200
Message-ID: <2220890.jZfb76A358@phil>
In-Reply-To: <Y00o3M7SKAB/w9sW@donbot>
References: <20211029115014.264084-1-john@metanate.com> <d814394b-86c3-beb1-ddd4-04c65004f138@gmail.com> <Y00o3M7SKAB/w9sW@donbot>
MIME-Version: 1.0
Content-Transfer-Encoding: 7Bit
Content-Type: text/plain; charset="us-ascii"
Precedence: bulk

Am Montag, 17. Oktober 2022, 12:05:16 CEST schrieb John Keeping:
> Hi Johan,
> 
> On Mon, Oct 17, 2022 at 10:11:32AM +0200, Johan Jonker wrote:
> > Your patch contribution causes a kernel panic on MK808 with Rockchip rk3066a SoC.
> > Would you like to contribute to fix this issue?
> > The assumtion that drm_fbdev_generic_setup() does what rockchip_drm_fbdev_init did is not true!
> > A revert makes it work again.
> 
> It looks like there are 3 different ways to end up with -ENOMEM here,
> can you track down whether you're hitting one of the cases in
> rockchip_gem_prime_vmap() or if it's the iosys_map_is_null case in
> drm_gem_vmap()?
> 
> I guess the memory usage increases slightly using the generic code and
> RK3066 has less memory available.

also rk3066 and rk3188 do not have an iommu, so rely
on cma allocations.


Heiko