linux-kernel - Re: [RESEND PATCH v2 3/6] ARM: dts: stm32: support display on stm32f746-disco board

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 7 Jun 2023 14:49:36 +0200
From:   Dario Binacchi <dario.binacchi@...rulasolutions.com>
To:     Jagan Teki <jagan@...rulasolutions.com>
Cc:     linux-kernel@...r.kernel.org,
        Raphael Gallais-Pou <raphael.gallais-pou@...s.st.com>,
        linux-arm-kernel@...ts.infradead.org,
        dri-devel@...ts.freedesktop.org,
        Philippe Cornu <philippe.cornu@...s.st.com>,
        Amarula patchwork <linux-amarula@...rulasolutions.com>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        michael@...rulasolutions.com,
        linux-stm32@...md-mailman.stormreply.com,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        Conor Dooley <conor+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Rob Herring <robh+dt@...nel.org>, devicetree@...r.kernel.org
Subject: Re: [RESEND PATCH v2 3/6] ARM: dts: stm32: support display on
 stm32f746-disco board

Hi Jagan,

On Wed, Jun 7, 2023 at 8:43 AM Jagan Teki <jagan@...rulasolutions.com> wrote:
>
> On Wed, Jun 7, 2023 at 12:01 PM Dario Binacchi
> <dario.binacchi@...rulasolutions.com> wrote:
> >
> > Add support to Rocktech RK043FN48H display on stm32f746-disco board.
> >
> > Signed-off-by: Dario Binacchi <dario.binacchi@...rulasolutions.com>
> > ---
> >
> > (no changes since v1)
> >
> >  arch/arm/boot/dts/stm32f746-disco.dts | 51 +++++++++++++++++++++++++++
> >  1 file changed, 51 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/stm32f746-disco.dts b/arch/arm/boot/dts/stm32f746-disco.dts
> > index c11616ed5fc6..cda423b6a874 100644
> > --- a/arch/arm/boot/dts/stm32f746-disco.dts
> > +++ b/arch/arm/boot/dts/stm32f746-disco.dts
> > @@ -60,10 +60,41 @@ memory@...00000 {
> >                 reg = <0xC0000000 0x800000>;
> >         };
> >
> > +       reserved-memory {
> > +               #address-cells = <1>;
> > +               #size-cells = <1>;
> > +               ranges;
> > +
> > +               linux,cma {
> > +                       compatible = "shared-dma-pool";
> > +                       no-map;
> > +                       size = <0x80000>;
> > +                       linux,dma-default;
> > +               };
> > +       };
>
> This looks unrelated to display enablement, isn't it?

Without the "reserved-memory" node, it is not possible to allocate
memory for the framebuffer.
I got this error:
stm32-display 40016800.display-controller: [drm] *ERROR* failed to
allocate buffer with size 139264

Thanks and regards,
Dario

>
> Jagan.



--

Dario Binacchi

Senior Embedded Linux Developer

dario.binacchi@...rulasolutions.com

__________________________________


Amarula Solutions SRL

Via Le Canevare 30, 31100 Treviso, Veneto, IT

T. +39 042 243 5310
info@...rulasolutions.com

www.amarulasolutions.com