linux-kernel - Re: [PATCH v4 1/3] arm64: dts: rockchip: Add missing pinctrl for PCIe30x4 node

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] [day] [month] [year] [list]

Message-ID: <CANAwSgTTeHvzCZ=PTVFAqPOhwcs9GeYFqRRMiog+AnbEnZgixg@mail.gmail.com>
Date: Sun, 28 Jul 2024 11:34:42 +0530
From: Anand Moon <linux.amoon@...il.com>
To: Jonas Karlman <jonas@...boo.se>
Cc: Heiko Stuebner <heiko@...ech.de>, Rob Herring <robh@...nel.org>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, devicetree@...r.kernel.org, 
	linux-arm-kernel@...ts.infradead.org, linux-rockchip@...ts.infradead.org, 
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 1/3] arm64: dts: rockchip: Add missing pinctrl for
 PCIe30x4 node

Hi Jonas,

On Sat, 27 Jul 2024 at 01:37, Jonas Karlman <jonas@...boo.se> wrote:
>
> Hi Anand,
>
> Sorry for no reply to your v3.
>
> On 2024-07-26 13:00, Anand Moon wrote:
> > Add missing pinctrl settings for PCIe 3.0 x4 clock request and wake
> > signals. Each component of PCIe communication have the following control
> > signals: PERST, WAKE, CLKREQ, and REFCLK. These signals work to generate
> > high-speed signals and communicate with other PCIe devices.
> > Used by root complex to endpoint depending on the power state.
> >
> > PERST is referred to as a fundamental reset. PERST should be held low
> > until all the power rails in the system and the reference clock are stable.
> > A transition from low to high in this signal usually indicates the
> > beginning of link initialization.
> >
> > WAKE signal is an active-low signal that is used to return the PCIe
> > interface to an active state when in a low-power state.
> >
> > CLKREQ signal is also an active-low signal and is used to request the
> > reference clock.
> >
> > Rename node from 'pcie3' to 'pcie30x4' to align with schematic
> > nomenclature.
> >
> > Signed-off-by: Anand Moon <linux.amoon@...il.com>
> > ---
> > v4: rebase on master, used RK_FUNC_GPIO GPIO function instead of PIN
> > number.
>
> Why this change? Only reset should use gpio function, if I am not
> mistaken. Also how come you change the internal pull-up/down on these
> pins?, and why do they differ for each pcie node in this series?
>
> Please see [1] for some discussion related to these pins.

I thought every board-specific dts supported GPIO function,
>
> """
> The PERST is for sure should work as GPIO, and the same as WAKE;
>
> for CLKREQ, only those board want to support L1SS need to work as
> function IO,
> """
Ok understood.
>
> As stated earlier only the reset pin need to be muxed to GPIO function,
> and that should also matches the only pin controlled with gpio in the
> driver, if I am not mistaken.

I will drop this in the next version.

>
> [1] https://lore.kernel.org/u-boot/6de0ee14-3d85-4fda-af9d-9be7e0057dc8@rock-chips.com/

I'm sorry, I did not read the complete email thread.
>
> Regards,
> Jonas
>
Thanks
-Anand