From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f43.google.com (mail-lf1-f43.google.com [209.85.167.43]) by mx.groups.io with SMTP id smtpd.web09.11466.1614261649355884554 for ; Thu, 25 Feb 2021 06:00:49 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@gmail.com header.s=20161025 header.b=OEd9ENsR; spf=pass (domain: gmail.com, ip: 209.85.167.43, mailfrom: andrey.z@gmail.com) Received: by mail-lf1-f43.google.com with SMTP id h125so8677766lfd.7 for ; Thu, 25 Feb 2021 06:00:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=8Iss20er/GVqpWxQOm7fztYKp3kTu0+/WX9CKpaQJEo=; b=OEd9ENsRlNm8UznCmjcCYa3PNBwk+mYo5tm91rdDXG4l7eC1827X/6Bz7I2jxfbeCd MXlGmqNXhuhrEUlqe/2fNTH0pXtka0ZTyZh/mVrBGOxZS6Uk7uxJFmIMUvCYSQgnMKfL 41DeCxAS/8Q3WB14TuaW+nhQYW6WqIYDVwU60+6G/J3NqtLPcUE1rfoGoi0aARLb1+yi ePjZl/utNokKayP+u5Rolv+mkhEhakLic9jH0bjdiZDcxqQq9o4JmvWfmpIa1X4HG17k hAyjUvsJQjCkDzseQmgrv4Pm6LERv0wfSBoG3bm4kTC5oEg8fTcuLCaroPVfKG4zwBZQ 4nvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=8Iss20er/GVqpWxQOm7fztYKp3kTu0+/WX9CKpaQJEo=; b=XxcNB7SMvFjCYHMjGDMDi2nyZLdP4IdEgluuLD7hzFfmrCitoHgMMpm8xeoEX+ZNM6 eEv5NPfyxMv5Ru/hArQ/kyWlaZQYkKlSE/bM20yoGdEIFekbFXmgp5ueSQi+23t9YL88 17n5anRwhGR9HqIDMLDGm482BYYHKMRwi6z7pRbq1n0edatEeahw3iuATm6KbgIoCjBE x9cg3U1fVDH1CDvYM6JYpAAQjQHrnKOhwrzrdGdZhmKRVUIGaGA8m/OijqXgArxm1hzO dY1xFVtwIwjzFotEPHovKqwdyMWfKMpPsMIkyLo9HAVY/tdCuG1/maPnY2bxyW9RSniW lrLA== X-Gm-Message-State: AOAM5330ZRGykUw1tjhM6wfxb606pAVkc3zlqNK5hkdwlQixj6+N4+YZ FWnuR4Qx36LBUQseuCWUNnS6cbW1K8ZnuVWFl6M= X-Google-Smtp-Source: ABdhPJyqOE7U2kra9UYsWam8AclefDmn8jiifVg7rNuYj+x1pFECvfipRXxvNk6eAZuPdqdwHUUF0m6IH5FEnzKh8U8= X-Received: by 2002:a19:f713:: with SMTP id z19mr2065393lfe.50.1614261647277; Thu, 25 Feb 2021 06:00:47 -0800 (PST) MIME-Version: 1.0 References: <12bb83d9-625a-f967-ed15-9602fc4cd46b@faresoftware.it> <910eca81-bcb4-c4b2-d591-9a853026f184@beam.ltd.uk> <9d621536-e38e-c8ee-4d5e-dc3f24fb09f1@beam.ltd.uk> <30d6ff10b73bd117198a8e2dd3e47388@basmevissen.nl> <78459aa4ec6360c05752a8bc1d44eac5@basmevissen.nl> In-Reply-To: From: "Andrey Zhizhikin" Date: Thu, 25 Feb 2021 15:00:35 +0100 Message-ID: Subject: Re: [meta-freescale] imx6dl dunfell and kernel: linux-fslc or linux-fslc-imx? To: Bas Mevissen Cc: Otavio Salvador , Terry Barnaby , meta-freescale@lists.yoctoproject.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Feb 25, 2021 at 2:22 PM Bas Mevissen wrote: > > On 2021-02-25 14:04, Andrey Zhizhikin wrote: > > On Thu, Feb 25, 2021 at 1:55 PM Bas Mevissen > > wrote: > >> > >> On 2021-02-25 13:32, Andrey Zhizhikin wrote: > >> > Hello Bas, > >> > > >> > On Thu, Feb 25, 2021 at 1:18 PM Bas Mevissen > >> > wrote: > >> >> > >> >> On 2021-02-25 12:21, Otavio Salvador wrote: > >> >> > Em qui., 25 de fev. de 2021 =C3=A0s 06:53, Terry Barnaby > >> >> > escreveu: > >> >> >> From what I am seeing I will have to use a NXP fsl-* based > >> >> >> distribution > >> >> >> to support the imx hardware video processing features. I have bu= ilt > >> >> >> such > >> >> >> a distro with both linux-fslc-imx and limux-imx kernels (I think= !) for > >> >> >> the Wandboard, which boots and runs but the HDMI display was not > >> >> >> functional. I will persevere looking at that. > >> >> > > >> >> > No, you don't. You can use linux-fslc (mainline) and fslc-* distr= os as > >> >> > i.MX6 has full mainline support. At O.S. Systems we have been usi= ng > >> >> > Linux mainline with many customers with great success. > >> >> > > >> >> > >> >> Wouldn't make sense to first evaluate the performance of the platfo= rm > >> >> (as Terry plans to do) first on an NXP fsl-* distro? In that case o= ne > >> >> can get direct support from NXP if required. After that, derive you= r > >> >> own > >> >> distro from fslc-*. > >> > > >> > This might not be quite indicative, as the NXP kernel might have som= e > >> > "shortcuts" to boost performance in certain areas, sacrificing > >> > conformance of the source code. > >> > > >> > >> At least you get an idea of what the HW platform can do. > >> > >> > You might experience the situation that video performs quite well, b= ut > >> > then after opting for NXP kernel - you might find that some other > >> > areas are not working as expected (some other domains). This would p= ut > >> > you in a situation that you've already committed to choose and deplo= y > >> > the NXP-based BSP and would leave you to solve the issues in those > >> > domains on your own efforts. > >> > > >> > This is my pure speculation here, so take it with a grain of salt > >> > though. :) > >> > > >> IMHO, you should never base your *product* on FSL. It is (at least, > >> that > >> is what was told me by (then) Freescale field engineers) only there to > >> demonstrate the platform. Maybe that has changed over time. > > > > That is exactly what I implied, below statement is about that. > > > Ok, I missed that obviously. > > >> > >> When there is a huge performance difference between fsl and fslc, it > >> needs to be resolved. > > > > By whom? This would lead to a situation that community does not take > > responsibility for NXP and visa-versa. In this case - I have a bad > > feeling that the engineering team in the company that decided to use > > one flavor or another would be dealing with this fact. And this is > > what I've also described as potential outcome. > > > > It is actually that interaction between the community and NXP that has > brought i.MX support at the level it has. So if a performance problem > might pop up, it is that same combination that can and will work > together to get it resolved. It is to the company/person who found the > issue to bring it up (here) and not to resolve it as that requires > capabilities that are not so widespread. In ideal situation - that would be a way to go. But in this case I would expect that all patches that are present in NXP kernel tree are posted upstream, so there would be no deviation and hence - no performance differences between NXP and upstream kernels. Of course, the problem when found - can be reported, but (a) I do not believe that this list is a proper destination for such issues, as it discuss the OE and not kernel-specific performance issues; and (b) regressions can come from any side (NXP or upstream), which makes it harder to bisect which side to be looked at. I'm not saying that this is an impossible thing to solve, but in reality the vast majority of efforts to solve those issues are landing up at the side of those persons who've discovered them in the first place. This is all my point of view on the subject, and might deviate on a case-by-case basis. > > >> > >> > IMHO, this should be considered and before the final product receive= s > >> > commitment to use either of BSP flavors - all areas should be > >> > validated, not only the performance aspects of Multimedia domain. > >> > > >> > >> Yes, when you have decided on the hardware to use. If you are > >> evaluating > >> the hardware to see whether it meets your requirements, you might want > >> to take the option that gives you the best impression of the > >> performance > >> that can be achieved without too much of a hassle. > >> (it is an important step to do, at a stage of the development where > >> time > >> is usually very limited, so you want a quick but reliable result). > > > > Correct, fully agree here. > > > >> > >> >> > >> >> BTW Would kernel.org stable kernel work as well on i.MX6 if you nee= d > >> >> graphics and video? I used it successfully for headless IOT > >> >> applications. > >> > > >> > As Fabio already indicated - this is possible. > >> > > >> > >> Fabio said "mainline". I'm not sure whether meant linux-fslc (as > >> Otavio > >> used it) or kernel.org. > > > > In this sense, linux-fslc *is* de-facto the kernel provided from > > kernel.org. It has a handful of patched that are not in upstream: > > > > $ git log --no-merges --oneline stable-git/linux-5.10.y..5.10.x+fslc > > 2b929f3dcf6c media: coda: Change firmware probing order > > dacfb877023a ARM: imx: add smp support for imx7d > > 10c7ebc67e34 drivers, misc: add U-Boot bootcount driver > > 67ea92db430f fec: Add disable_giga parameter to force 10/100 operation > > bc552ba32d60 MA-7633-2 [Android-Reboot]reboot to fastboot\recovery mode > > 695186a85a0d ARM: imx: add cpu_is_imx6() routine > > > >> So I wanted to check that. > >> > And that worked out brilliantly :-) > (thanks, see my response to Fabio on the same subject as well) > > >> >> > >> >> Bas. > >> >> > >> > > >> > -- > >> > Regards, > >> > Andrey. > >> > > >> > > > > > -- > > Regards, > > Andrey. > > Regards, > > Bas. --=20 Regards, Andrey.