All of lore.kernel.org
 help / color / mirror / Atom feed
From: Robin Murphy <robin.murphy@arm.com>
To: Sascha Hauer <s.hauer@pengutronix.de>, Mark Brown <broonie@kernel.org>
Cc: linux-rockchip@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	 Heiko Stuebner <heiko@sntech.de>,
	Michael Riesch <michael.riesch@wolfvision.net>,
	kernel@pengutronix.de
Subject: Re: [PATCH 3/4] soc: rockchip: power-domain: Add regulator support
Date: Wed, 22 Dec 2021 12:54:06 +0000	[thread overview]
Message-ID: <baa1603a-a6e2-4a32-a5fb-dc1eff01189c@arm.com> (raw)
In-Reply-To: <20211222104036.GY6003@pengutronix.de>

On 2021-12-22 10:40, Sascha Hauer wrote:
> On Mon, Dec 20, 2021 at 12:53:58PM +0000, Mark Brown wrote:
>> On Mon, Dec 20, 2021 at 10:44:35AM +0100, Sascha Hauer wrote:
>>
>>> Well, all true and on one specific board the regulator is indeed not
>>> optional. However, on all other power domains that don't need a
>>> regulator and all other boards and all other SoCs this driver is used we
>>> now get:
>>
>> This seems unlikely to be board specific, if the chip requires power the
>> chip requires power.  If there are power domains that don't take
>> external supplies then they shouldn't be requesting any regulators and
>> should be fixed.
>>
>>> [    0.185588] rk-power-domain rk-power-domain.8: supply power not found, using dummy regulator
>>
>> It seems vanishingly unlikely that the SoC takes a single supply called
>> "power" shared by everything in the SoC but that is what the code
>> appears to be requesting - the power domains should be requesting the
>> supplies they actually use, and as ever the supplies should be named
>> such that someone looking at the schematic can hook them up.  The
>> general recommendation is to use the names used in the datasheet.
> 
> Ok. I'll change the patch in a way that only for the GPU power domain on
> rk3568 a supply is requested. That's the one power domain I know that a
> regulator is needed. I'm sure there are more, if not on rk3568 then
> probably on other SoCs the driver handles. Once we notice that other
> domains need a supply we'll have to add the supply name to driver data
> for that domain.

Certainly RK3399 (and I guess RK3288 too) suffers from the same 
priority-inversion issue of being unaware that VD_GPU needs power before 
PD_GPU can be successfully turned on to probe the GPU to claim and 
enable the regulator (via "mali-supply" for DVFS purposes) that needed 
to be on in the first place. Currently all the boards are bodging around 
this with "regulator-always-on" (e.g. commit 06b2818678d9).

Thanks,
Robin.

_______________________________________________
Linux-rockchip mailing list
Linux-rockchip@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-rockchip

WARNING: multiple messages have this Message-ID
From: Robin Murphy <robin.murphy@arm.com>
To: Sascha Hauer <s.hauer@pengutronix.de>, Mark Brown <broonie@kernel.org>
Cc: linux-rockchip@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	 Heiko Stuebner <heiko@sntech.de>,
	Michael Riesch <michael.riesch@wolfvision.net>,
	kernel@pengutronix.de
Subject: Re: [PATCH 3/4] soc: rockchip: power-domain: Add regulator support
Date: Wed, 22 Dec 2021 12:54:06 +0000	[thread overview]
Message-ID: <baa1603a-a6e2-4a32-a5fb-dc1eff01189c@arm.com> (raw)
In-Reply-To: <20211222104036.GY6003@pengutronix.de>

On 2021-12-22 10:40, Sascha Hauer wrote:
> On Mon, Dec 20, 2021 at 12:53:58PM +0000, Mark Brown wrote:
>> On Mon, Dec 20, 2021 at 10:44:35AM +0100, Sascha Hauer wrote:
>>
>>> Well, all true and on one specific board the regulator is indeed not
>>> optional. However, on all other power domains that don't need a
>>> regulator and all other boards and all other SoCs this driver is used we
>>> now get:
>>
>> This seems unlikely to be board specific, if the chip requires power the
>> chip requires power.  If there are power domains that don't take
>> external supplies then they shouldn't be requesting any regulators and
>> should be fixed.
>>
>>> [    0.185588] rk-power-domain rk-power-domain.8: supply power not found, using dummy regulator
>>
>> It seems vanishingly unlikely that the SoC takes a single supply called
>> "power" shared by everything in the SoC but that is what the code
>> appears to be requesting - the power domains should be requesting the
>> supplies they actually use, and as ever the supplies should be named
>> such that someone looking at the schematic can hook them up.  The
>> general recommendation is to use the names used in the datasheet.
> 
> Ok. I'll change the patch in a way that only for the GPU power domain on
> rk3568 a supply is requested. That's the one power domain I know that a
> regulator is needed. I'm sure there are more, if not on rk3568 then
> probably on other SoCs the driver handles. Once we notice that other
> domains need a supply we'll have to add the supply name to driver data
> for that domain.

Certainly RK3399 (and I guess RK3288 too) suffers from the same 
priority-inversion issue of being unaware that VD_GPU needs power before 
PD_GPU can be successfully turned on to probe the GPU to claim and 
enable the regulator (via "mali-supply" for DVFS purposes) that needed 
to be on in the first place. Currently all the boards are bodging around 
this with "regulator-always-on" (e.g. commit 06b2818678d9).

Thanks,
Robin.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2021-12-22 12:54 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-17 13:09 [PATCH 0/4] " Sascha Hauer
2021-12-17 13:09 ` Sascha Hauer
2021-12-17 13:09 ` [PATCH 1/4] soc: rockchip: power-domain: register device for each domain Sascha Hauer
2021-12-17 13:09   ` Sascha Hauer
2021-12-17 13:09 ` [PATCH 2/4] soc: rockchip: power-domain: Use devm_clk_bulk_get_all() Sascha Hauer
2021-12-17 13:09   ` Sascha Hauer
2021-12-17 13:09 ` [PATCH 3/4] soc: rockchip: power-domain: Add regulator support Sascha Hauer
2021-12-17 13:09   ` Sascha Hauer
2021-12-20  9:44   ` Sascha Hauer
2021-12-20  9:44     ` Sascha Hauer
2021-12-20 10:46     ` Robin Murphy
2021-12-20 10:46       ` Robin Murphy
2021-12-20 12:56       ` Mark Brown
2021-12-20 12:56         ` Mark Brown
2021-12-20 12:53     ` Mark Brown
2021-12-20 12:53       ` Mark Brown
2021-12-22 10:40       ` Sascha Hauer
2021-12-22 10:40         ` Sascha Hauer
2021-12-22 12:54         ` Robin Murphy [this message]
2021-12-22 12:54           ` Robin Murphy
2021-12-22 13:00           ` Mark Brown
2021-12-22 13:00             ` Mark Brown
2021-12-22 13:19             ` Robin Murphy
2021-12-22 13:19               ` Robin Murphy
2021-12-22 13:25               ` Mark Brown
2021-12-22 13:25                 ` Mark Brown
2021-12-22 13:29                 ` Michael Riesch
2021-12-22 13:29                   ` Michael Riesch
2021-12-22 13:37                   ` Michael Riesch
2021-12-22 13:40                   ` Mark Brown
2021-12-22 13:40                     ` Mark Brown
2022-02-23  8:51                     ` Michael Riesch
2022-02-23  8:51                       ` Michael Riesch
2021-12-17 13:09 ` [PATCH 4/4] dt-bindings: power: rockchip: Add power-supply to domain nodes Sascha Hauer
2021-12-17 13:09   ` Sascha Hauer

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=baa1603a-a6e2-4a32-a5fb-dc1eff01189c@arm.com \
    --to=robin.murphy@arm.com \
    --cc=broonie@kernel.org \
    --cc=heiko@sntech.de \
    --cc=kernel@pengutronix.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-rockchip@lists.infradead.org \
    --cc=michael.riesch@wolfvision.net \
    --cc=s.hauer@pengutronix.de \
    --subject='Re: [PATCH 3/4] soc: rockchip: power-domain: Add regulator support' \
    /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

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.