From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44BF5C27C76 for ; Wed, 25 Jan 2023 12:49:16 +0000 (UTC) Subject: Re: [meta-raspberrypi] Is Preempt-rt still supported in master / latest releases? To: yocto@lists.yoctoproject.org From: "Carles Sole" X-Originating-Location: Stuttgart, Baden-Württemberg, DE (194.39.218.19) X-Originating-Platform: Windows Firefox 102 User-Agent: GROUPS.IO Web Poster MIME-Version: 1.0 Date: Wed, 25 Jan 2023 04:49:13 -0800 References: In-Reply-To: Message-ID: <20057.1674650953536874663@lists.yoctoproject.org> Content-Type: multipart/alternative; boundary="1dttwcoMZmhZyIuBAJIL" List-Id: X-Webhook-Received: from li982-79.members.linode.com [45.33.32.79] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Wed, 25 Jan 2023 12:49:16 -0000 X-Groupsio-URL: https://lists.yoctoproject.org/g/yocto/message/59057 --1dttwcoMZmhZyIuBAJIL Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Hi Alex, Andrei, thanks for your reply. Based on your feedback I've tried the following: - I have downloaded the patch patch-5.15.86-rt56.patch from https://cdn.ker= nel.org/pub/linux/kernel/projects/rt/5.15/ and stored in ./meta-raspberrypi= /recipes-kernel/linux/files - I have created a file linux-raspberrypi_%.bbappend in ./meta-raspberrypi/= recipes-kernel/linux - I have created a .cfg file with CONFIG_PREEMPT_RT_FULL =3D y in ./meta-ra= spberrypi/recipes-kernel/linux/files - I have added both patch and cfg file in bbappend using SRC_URI:append:rpi= . I can observe the following: - patch and cfg files are available in ./build/tmp/work/raspberrypi4_64-agl= -linux/linux-raspberrypi/1_5.15.34+gitAUTOINC+e1b976ee4f_0086da6acd-r0 - new folder linux-raspberrypi4_64-preempt-rt-build is available inside the= folder above. But the problem seems to be that CONFIG_PREEMPT_RT =3D y is = not applied to the .config file. So it seems the preempt-rt kernel is built= but without the full preempt-rt support. - When I do bitbake linux-raspberrypi -c menuconfig I cannot select the ful= l real time preempt kernel, only preemptible option available is --> Preemp= tible Kernel (Low-Latency Desktop). Fully Preemptible Kernel (Real-Time) is= not available. - When I flash the image in the Rpi4 and run uname -r I see that the rt ker= nel has been built --> 5.15.34.rt56.v8 - but only with PREEMPT option but without RT when I do uname -v --> #1 SMP= PREEMPT Tue Aug 9 21:20:00 UTC 2022 (without RT). I have tried building linux-yocto-rt for qemu and there I see that CONFIG_P= REEMP_RT =3D y is available in the .config file. Also if I open menuconfig = I have the option to select in General setup --> Preemption Model --> Fully= Preemptible Kernel (Real-Time) If you can provide any hints on what am I missing it would be highly apprec= iated. Best Regards, Carles --1dttwcoMZmhZyIuBAJIL Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable Hi Alex, Andrei,

thanks for your reply. Based on your feedback I= 've tried the following:
- I have downloaded the patch patch-5.15.86-r= t56.patch from https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.15/ an= d stored in ./meta-raspberrypi/recipes-kernel/linux/files
- I have cre= ated a file linux-raspberrypi_%.bbappend in ./meta-raspberrypi/recipes-kern= el/linux
- I have created a .cfg file with CONFIG_PREEMPT_RT_FULL =3D = y in ./meta-raspberrypi/recipes-kernel/linux/files
- I have added both= patch and cfg file in bbappend using SRC_URI:append:rpi.

I can = observe the following:
- patch and cfg files are available in ./build/= tmp/work/raspberrypi4_64-agl-linux/linux-raspberrypi/1_5.15.34+gitAUTOINC+e= 1b976ee4f_0086da6acd-r0
- new folder linux-raspberrypi4_64-preempt-rt-= build is available inside the folder above. But the problem seems to be tha= t CONFIG_PREEMPT_RT =3D y is not applied to the .config file. So it seems t= he preempt-rt kernel is built but without the full preempt-rt support.
- When I do bitbake linux-raspberrypi -c menuconfig I cannot select the fu= ll real time preempt kernel, only preemptible option available is --> Pr= eemptible Kernel (Low-Latency Desktop). Fully Preemptible Kernel (Real-Time= ) is not available.
- When I flash the image in the Rpi4 and run uname= -r I see that the rt kernel has been built --> 5.15.34.rt56.v8
- = but only with PREEMPT option but without RT when I do uname -v --> #1 SM= P PREEMPT Tue Aug 9 21:20:00 UTC 2022 (without RT).

I have tried= building linux-yocto-rt for qemu and there I see that CONFIG_PREEMP_RT =3D= y is available in the .config file. Also if I open menuconfig I have the o= ption to select in General setup --> Preemption Model --> Fully Preem= ptible Kernel (Real-Time)

If you can provide any hints on what = am I missing it would be highly appreciated.

Best Regards,
= Carles --1dttwcoMZmhZyIuBAJIL--