dri-devel.lists.freedesktop.org archive mirror
 help / color / mirror / Atom feed
From: Jonathan Bakker <xc-racer2@live.ca>
To: Paul Cercueil <paul@crapouillou.net>,
	"H. Nikolaus Schaller" <hns@goldelico.com>
Cc: "Mark Rutland" <mark.rutland@arm.com>,
	"David Airlie" <airlied@linux.ie>,
	"James Hogan" <jhogan@kernel.org>,
	dri-devel@lists.freedesktop.org, linux-mips@vger.kernel.org,
	linux-samsung-soc@vger.kernel.org, letux-kernel@openphoenux.org,
	"Paul Burton" <paulburton@kernel.org>,
	"Krzysztof Kozlowski" <krzk@kernel.org>,
	"Tony Lindgren" <tony@atomide.com>,
	"Chen-Yu Tsai" <wens@csie.org>, "Kukjin Kim" <kgene@kernel.org>,
	devicetree@vger.kernel.org,
	"Benoît Cousson" <bcousson@baylibre.com>,
	"Rob Herring" <robh+dt@kernel.org>,
	linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	"Thomas Bogendoerfer" <tsbogend@alpha.franken.de>,
	"Philipp Rossak" <embed3d@gmail.com>,
	openpvrsgx-devgroup@letux.org, linux-kernel@vger.kernel.org,
	"Ralf Baechle" <ralf@linux-mips.org>,
	kernel@pyra-handheld.com
Subject: Re: [PATCH v7 08/12] arm: dts: s5pv210: Add node for SGX 540
Date: Sun, 26 Apr 2020 07:57:12 -0700	[thread overview]
Message-ID: <BN6PR04MB0660A180D2069848E5C03D7EA3AE0@BN6PR04MB0660.namprd04.prod.outlook.com> (raw)
In-Reply-To: <NYBE9Q.YH08US7A7DC3@crapouillou.net>

Hi Paul,

On 2020-04-26 5:56 a.m., Paul Cercueil wrote:
> 
> 
> Le ven. 24 avril 2020 à 22:34, H. Nikolaus Schaller <hns@goldelico.com> a écrit :
>> From: Jonathan Bakker <xc-racer2@live.ca>
>>
>> All s5pv210 devices have a PowerVR SGX 540 (revision 120) attached.
>>
>> There is no external regulator for it so it can be enabled by default.
>>
>> Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
>> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
>> ---
>>  arch/arm/boot/dts/s5pv210.dtsi | 13 +++++++++++++
>>  1 file changed, 13 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/s5pv210.dtsi b/arch/arm/boot/dts/s5pv210.dtsi
>> index 2ad642f51fd9..abbdda205c1b 100644
>> --- a/arch/arm/boot/dts/s5pv210.dtsi
>> +++ b/arch/arm/boot/dts/s5pv210.dtsi
>> @@ -512,6 +512,19 @@ vic3: interrupt-controller@f2300000 {
>>              #interrupt-cells = <1>;
>>          };
>>
>> +        gpu: gpu@f3000000 {
>> +            compatible = "samsung,s5pv210-sgx540-120";
>> +            reg = <0xf3000000 0x10000>;
>> +            interrupt-parent = <&vic2>;
>> +            interrupts = <10>;
>> +            clock-names = "core";
>> +            clocks = <&clocks CLK_G3D>;
>> +
>> +            assigned-clocks = <&clocks MOUT_G3D>, <&clocks DOUT_G3D>;
>> +            assigned-clock-rates = <0>, <66700000>;
>> +            assigned-clock-parents = <&clocks MOUT_MPLL>;
> 
> What are these clocks for, and why are they reparented / reclocked?
> 
> Shouldn't they be passed to 'clocks' as well?
> 
> -Paul
> 

The G3D clock system can have multiple parents, and for stable operation
it's recommended to use the MPLL clock as the parent (which in turn
is actually a mux as well).  MOUT_G3D is simply the mux for CLK_G3D
(SGX core clock), DOUT_G3D is the divider.  DOUT_G3D could equally be CLK_G3D
(and probably should be, for readability) as CLK_G3D is simply the gate and
DOUT_G3D is the divider for it.

The SGX clock layout on S5PV210 looks something like this:

        MOUT_MPLL -----------> MOUT_G3D ---> DOUT_G3D  ---> CLK_G3D
(selectable parent clock)      (mux)    ---> (divider) ---> (gate)

This is fairly common for older Samsung SoCs, eg having a look at
arch/arm/boot/dts/exynos4210-universal_c210.dts you can see that
the FIMC clocks are parented to MPLL and have a rate set.

>> +        };
>> +
>>          fimd: fimd@f8000000 {
>>              compatible = "samsung,s5pv210-fimd";
>>              interrupt-parent = <&vic2>;
>> -- 
>> 2.25.1
>>
> 
> 

Thanks,
Jonathan
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

  reply	other threads:[~2020-04-27  7:22 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-24 20:34 [PATCH v7 00/12] ARM/MIPS: DTS: add child nodes describing the PVRSGX GPU present in some OMAP SoC and JZ4780 (and many more) H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 01/12] dt-bindings: add img, pvrsgx.yaml for Imagination GPUs H. Nikolaus Schaller
2020-04-24 20:43   ` H. Nikolaus Schaller
2020-04-26 13:11   ` Paul Cercueil
2020-05-02 20:26     ` H. Nikolaus Schaller
2020-05-03 12:52       ` Paul Cercueil
2020-05-03 13:31         ` H. Nikolaus Schaller
2020-05-03 14:18           ` Paul Cercueil
2020-05-03 15:01             ` [PATCH v7 01/12] dt-bindings: add img,pvrsgx.yaml " Tony Lindgren
2020-05-15  7:58               ` [PATCH v7 01/12] dt-bindings: add img, pvrsgx.yaml " H. Nikolaus Schaller
2020-05-03 16:41             ` H. Nikolaus Schaller
2020-05-15  7:18               ` H. Nikolaus Schaller
2020-04-26 19:36   ` Philipp Rossak
2020-04-26 20:59     ` H. Nikolaus Schaller
2020-05-05 15:53   ` [PATCH v7 01/12] dt-bindings: add img,pvrsgx.yaml " Rob Herring
2020-05-15  7:59     ` [PATCH v7 01/12] dt-bindings: add img, pvrsgx.yaml " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 02/12] ARM: DTS: am33xx: add sgx gpu child node H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 03/12] ARM: DTS: am3517: " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 04/12] ARM: DTS: omap34xx: " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 05/12] ARM: DTS: omap36xx: " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 06/12] ARM: DTS: omap4: " H. Nikolaus Schaller
2020-04-26 12:50   ` Paul Cercueil
2020-04-28  7:59     ` H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 07/12] ARM: DTS: omap5: " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 08/12] arm: dts: s5pv210: Add node for SGX 540 H. Nikolaus Schaller
2020-04-26 12:56   ` Paul Cercueil
2020-04-26 14:57     ` Jonathan Bakker [this message]
2020-04-27 15:46       ` Krzysztof Kozlowski
2020-04-28 21:39         ` Jonathan Bakker
2020-04-28 22:58           ` Jonathan Bakker
2020-04-29  8:47             ` Maxime Ripard
2020-04-29 12:26             ` Paul Cercueil
2020-04-24 20:34 ` [PATCH v7 09/12] ARM: dts: sun6i: a31: add sgx gpu child node H. Nikolaus Schaller
2020-04-26 12:53   ` Paul Cercueil
2020-04-26 19:31     ` Philipp Rossak
2020-04-24 20:34 ` [PATCH v7 10/12] ARM: dts: sun6i: a31s: " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 11/12] ARM: dts: sun8i: a83t: " H. Nikolaus Schaller
2020-04-24 20:34 ` [PATCH v7 12/12] MIPS: DTS: jz4780: add sgx gpu node H. Nikolaus Schaller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=BN6PR04MB0660A180D2069848E5C03D7EA3AE0@BN6PR04MB0660.namprd04.prod.outlook.com \
    --to=xc-racer2@live.ca \
    --cc=airlied@linux.ie \
    --cc=bcousson@baylibre.com \
    --cc=devicetree@vger.kernel.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=embed3d@gmail.com \
    --cc=hns@goldelico.com \
    --cc=jhogan@kernel.org \
    --cc=kernel@pyra-handheld.com \
    --cc=kgene@kernel.org \
    --cc=krzk@kernel.org \
    --cc=letux-kernel@openphoenux.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=linux-omap@vger.kernel.org \
    --cc=linux-samsung-soc@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=openpvrsgx-devgroup@letux.org \
    --cc=paul@crapouillou.net \
    --cc=paulburton@kernel.org \
    --cc=ralf@linux-mips.org \
    --cc=robh+dt@kernel.org \
    --cc=tony@atomide.com \
    --cc=tsbogend@alpha.franken.de \
    --cc=wens@csie.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).