Re: [PATCH 1/2] arm64: dts: freescale: imx93-phyboard-nash: Add jtag overlay

[Alberto Merciai <alb3rt0.m3rciai@gmail.com>]

On Tue, Oct 28, 2025 at 07:23:57AM +0100, Primoz Fiser wrote:
> Hi both,
> 
> On 24. 10. 25 18:54, Frank Li wrote:
> > On Fri, Oct 24, 2025 at 04:36:40PM +0200, Alberto Merciai wrote:
> >> On Fri, Oct 24, 2025 at 09:30:31AM -0400, Frank Li wrote:
> >>> On Tue, Oct 07, 2025 at 10:40:27AM +0200, Primoz Fiser wrote:
> >>>> Add overlay to enable JTAG pins on the board's JTAG (X41) connector.
> >>>>
> >>>> Signed-off-by: Primoz Fiser <primoz.fiser@norik.com>
> >>>> ---
> >>>>  arch/arm64/boot/dts/freescale/Makefile        |  2 ++
> >>>>  .../freescale/imx93-phyboard-nash-jtag.dtso   | 26 +++++++++++++++++++
> >>>>  2 files changed, 28 insertions(+)
> >>>>  create mode 100644 arch/arm64/boot/dts/freescale/imx93-phyboard-nash-jtag.dtso
> >>>>
> >>>> diff --git a/arch/arm64/boot/dts/freescale/Makefile b/arch/arm64/boot/dts/freescale/Makefile
> >>>> index 525ef180481d..c72a6fdc5412 100644
> >>>> --- a/arch/arm64/boot/dts/freescale/Makefile
> >>>> +++ b/arch/arm64/boot/dts/freescale/Makefile
> >>>> @@ -356,10 +356,12 @@ dtb-$(CONFIG_ARCH_MXC) += imx93-kontron-bl-osm-s.dtb
> >>>>  dtb-$(CONFIG_ARCH_MXC) += imx93-phyboard-nash.dtb
> >>>>  dtb-$(CONFIG_ARCH_MXC) += imx93-phyboard-segin.dtb
> >>>>
> >>>> +imx93-phyboard-nash-jtag-dtbs += imx93-phyboard-nash.dtb imx93-phyboard-nash-jtag.dtbo
> >>>>  imx93-phyboard-nash-peb-wlbt-07-dtbs += imx93-phyboard-nash.dtb imx93-phyboard-nash-peb-wlbt-07.dtbo
> >>>>  imx93-phyboard-segin-peb-eval-01-dtbs += imx93-phyboard-segin.dtb imx93-phyboard-segin-peb-eval-01.dtbo
> >>>>  imx93-phyboard-segin-peb-wlbt-05-dtbs += imx93-phyboard-segin.dtb imx93-phyboard-segin-peb-wlbt-05.dtbo
> >>>>  imx93-phycore-rpmsg-dtbs += imx93-phyboard-nash.dtb imx93-phyboard-segin.dtb imx93-phycore-rpmsg.dtbo
> >>>> +dtb-$(CONFIG_ARCH_MXC) += imx93-phyboard-nash-jtag.dtb
> >>>>  dtb-$(CONFIG_ARCH_MXC) += imx93-phyboard-nash-peb-wlbt-07.dtb
> >>>>  dtb-$(CONFIG_ARCH_MXC) += imx93-phyboard-segin-peb-eval-01.dtb
> >>>>  dtb-$(CONFIG_ARCH_MXC) += imx93-phyboard-segin-peb-wlbt-05.dtb
> >>>> diff --git a/arch/arm64/boot/dts/freescale/imx93-phyboard-nash-jtag.dtso b/arch/arm64/boot/dts/freescale/imx93-phyboard-nash-jtag.dtso
> >>>> new file mode 100644
> >>>> index 000000000000..4744eabf95f3
> >>>> --- /dev/null
> >>>> +++ b/arch/arm64/boot/dts/freescale/imx93-phyboard-nash-jtag.dtso
> >>>> @@ -0,0 +1,26 @@
> >>>> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> >>>> +/*
> >>>> + * Copyright (C) 2025 PHYTEC Messtechnik GmbH
> >>>> + * Author: Primoz Fiser <primoz.fiser@norik.com>
> >>>> + */
> >>>> +
> >>>> +#include "imx93-pinfunc.h"
> >>>> +
> >>>> +/dts-v1/;
> >>>> +/plugin/;
> >>>> +
> >>>> +&gpio2 {
> >>>> +	pinctrl-names = "default";
> >>>> +	pinctrl-0 = <&pinctrl_jtag>;
> >>>> +};
> >>>
> >>> Use gpio to set pinctrl to no-gpio mode is strange. I am not sure if there
> >>> are better method, but at need comments here to show why have to do that.
> >>>
> >>
> >> In old imx6 platform we use pinctrl_hog for that purpose, is not?
> > 
> > It'd better than gpio, but I am not sure if pinctrl_hog still be supported
> > because I have not seen it for the long time.
> > 
> 
> I am OK with both suggestions:
> 
> 1) adding an explanation comment
> 2) Using pinctrl_hog method
> 
> Personally however, I would prefer method 1) since it would be better in
> this case because base customer dts can already contain default
> pinctrl_hog which would be overwritten by this overlay.

Good point, that is true.

> 
> Not that common, but can still happen.
> 
> What do you suggest for v2? 

I would say 1, IMO explaining that with a comments is the most
explicit way to do that.

BR,
Alberto

> 
> BR,
> Primoz
> 
> > Frank
> >>
> >>> Frank
> >>>> +
> >>>> +&iomuxc {
> >>>> +	pinctrl_jtag: jtaggrp {
> >>>> +		fsl,pins = <
> >>>> +			MX93_PAD_GPIO_IO24__JTAG_MUX_TDO	0x31e
> >>>> +			MX93_PAD_GPIO_IO25__JTAG_MUX_TCK	0x31e
> >>>> +			MX93_PAD_GPIO_IO26__JTAG_MUX_TDI	0x31e
> >>>> +			MX93_PAD_GPIO_IO27__JTAG_MUX_TMS	0x31e
> >>>> +		>;
> >>>> +	};
> >>>> +};
> >>>> --
> >>>> 2.34.1
> >>>>
> >>>
> 
> -- 
> Primoz Fiser
> phone: +386-41-390-545
> email: primoz.fiser@norik.com
> --
> Norik systems d.o.o.
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>