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

[Primoz Fiser]

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@xxxxxxxxx>
>>>> ---
>>>>  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@xxxxxxxxx>
>>>> + */
>>>> +
>>>> +#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.

Not that common, but can still happen.

What do you suggest for v2?

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@xxxxxxxxx
--
Norik systems d.o.o.
Your embedded software partner
Slovenia, EU
phone: +386-41-540-545
email: info@xxxxxxxxx