Re: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
Dear Philip, Thanks for your email. Unfortunately, I am in a rush now, but briefly: I think the long-term stability is indeed an important issue. Another issue is the use of existing software. And in my organisation and project there is a lot (!) of software that I am interested in using on a Xilinx/Zynq. Of course, that software was not developed in my group, but rather by a lot of people we are working with. Those people are more "software people" who don't care about the specificities of the Zynq but rather develop for mainline kernel and libc. Maybe, the second point becomes clearer with this remark, too: I am probably too naive, but I was thinking that I could use CentOS RPMs over a Xilinx kernel, of course making sure that I am using the right version of glibc for those. So, I would boot the Xilinx kernel, and then either take the installed RPMs and glibc from the rootfs or some NFS repository and try to run them. At least, this is what I would like to try out if I can find the time to ... Do you think this is completely unrealistic? The glibc version would be ways behind the one corresponding to the latest Xilinx kernel, so I thought that backwards compatibility should be guaranteed. There should only be a few specific drivers, like DMA, that I would have to take care of. I am further using ethernet, I2C, SPI, GPIO, and AXI memory access, but nothing for other specific hardware ... Cheers, Ralf. -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
Re: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
On 12/13/2017 04:06 AM, Ralf Spiwoks wrote: > Dear Sandeep and Mike, > > Thank you very much for your replies. > > I am not using video nor dual-parallel QSPI flash memory. But I need the > Xilinx DMA driver. > Is that a consistent part of the mainline Linux? Sorry, but I simply > don't know where to look. > > And apart from the drivers, there a no patches of Xilinx to other parts > of the kernel? > > Provocatively I might ask, why does Xilinx have a dedicated repository > for the kernel in > that case. Is it just for convenience? I've got some thoughts on this subject. This is a general problem in the embedded Linux space and creates a great deal of pain for people developing products based on Linux. So these thoughts are not Xilinx specific, but for this discussion Xilinx is the example. I regard the Xilinx Linux tree as a view into Xilinx internal engineering work. This is a nice thing to have for developing things, but is not a good thing for deploying in long lasting products. There is an excellent article (with video) here: https://www.linux.com/news/event/ELCE/2017/long-term-embedded-linux-maintenance-made-easier For a long lasting project, I want to see kernels built from the Linux LTS trees + patches to support things not in that kernel. These patches should look like they are being submitted upstream, not just dumps of commits. Ideally, they should be submitted upstream, so when I update my kernel to eliminate things like bugs and CVE's, the patches go away. In yocto speak, the kernel recipe for my board is a bbappend against the linux-yocto recipe. With a new YP release, I adjust the kernel version for the bbappend, drop patches that went upstream and fix patches that no longer apply. (This is why I want to see all work upstreamed) This is a process you can use to deliver products based on embedded Linux with a long life cycle and a credible plan to fix critical security vulnerabilities. (Another note specific to the email further down) > > I am also wondering, why the meta-xilinx recipe for the kernel build is > based on kernel 4.9 > while the "regular" build in the same Yocto version is 4.12, or did I > get something wrong. > > Sorry for asking so many questions, I am trying to make a point within > my organisation that > it is worth using Yocto. But they are holding against me that the Xilinx > kernel would contain > patches which are not accepted yet in the upstream kernel, and which > would present risks in > using a Xilinx kernel with AARCH64 RPMs from another disctribution (in > our case CentOS) - > which is actually what I am really after: I would like to have my Zynqs > running with other > software already developed in my organisation. > Are you thinking of using Centos rpm's layered over a Linux built from meta-xilinx? This is likely going to have issues with library versions etc. It isn't clear to me what you are trying to do. Philip > Thanks for any help with mu issue. > > Cheers, > Ralf. > > > PS: I signed up with the meta-xilinx mailing list many times, but never > got a confirmation > message. Is this normal? > > > On 12/13/2017 07:29 AM, Mike Looijmans wrote: >> On 12-12-17 16:20, Ralf Spiwoks wrote: >>> Hello! >>> >>> I am using Yocto and meta-xilinx to build the Linux kernel 4.9 for >>> a Zynq XC7Z030. Now, in my organization some people said that: >>> >>> "Xilinx currently runs a custom Linux distribution which ... has patches >>> to the kernel by Xilink which are not accepted yet in the upstream Linux >>> kernel." >>> >>> So, my question is: >>> What are the differences of the Xilinx Linux kernel w.r.t. to the >>> Linux kernel >>> (from kernel.org)? >> >> The main difference is the support for dual-parallel QSPI flash >> memory. The driver for that is in a state (and has been for years) >> that apparently cannot be upstreamed. >> >> So if your board doesn't have dual flash, I'd recommend using mainline >> Linux instead. >> >> >> Kind regards, >> >> Mike Looijmans >> System Expert >> >> TOPIC Products >> Materiaalweg 4, NL-5681 RJ Best >> Postbus 440, NL-5680 AK Best >> Telefoon: +31 (0) 499 33 69 79 >> E-mail: mike.looijm...@topicproducts.com >> Website: www.topicproducts.com >> >> Please consider the environment before printing this e-mail >> >> >> >> -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
Re: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
On 13 December 2017 at 19:06, Ralf Spiwoks wrote: > Dear Sandeep and Mike, > > Thank you very much for your replies. > > I am not using video nor dual-parallel QSPI flash memory. But I need the > Xilinx DMA driver. > Is that a consistent part of the mainline Linux? Sorry, but I simply don't > know where to look. Depends on what you need in terms of the xilinx dma driver, but there is an upstream driver. Though there is also some delta between the upstream driver and linux-xlnx. # git diff --stat v4.9..xilinx-v2017.3 -- drivers/dma/xilinx/xilinx_dma.c 1 file changed, 151 insertions(+), 126 deletions(-) > > And apart from the drivers, there a no patches of Xilinx to other parts of > the kernel? There is a significant delta between mainline and Xilinx kernel. Touching drivers, arch, soc, device trees, libfdt, some uapi headers, etc. You should use git diff to have a look if your a concerned. # git diff --stat v4.9..xilinx-v2017.3 584 files changed, 117100 insertions(+), 4039 deletions(-) > > Provocatively I might ask, why does Xilinx have a dedicated repository for > the kernel in > that case. Is it just for convenience? I believe the most general reason is that it is to provide support for their devices before they have upstreamed any changes. > > I am also wondering, why the meta-xilinx recipe for the kernel build is > based on kernel 4.9 > while the "regular" build in the same Yocto version is 4.12, or did I get > something wrong. Simple, the Xilinx vendor kernel is based on 4.9, and meta-xilinx defaults to selecting the Xilinx vendor kernel (linux-xlnx). Whilst the Yocto kernel is providing the mainline 4.12 kernel (linux-yocto supports 2/3 kernels at once - https://wiki.yoctoproject.org/wiki/Linux_Yocto). Do note though that linux-yocto does also have patches/source trees that are different for specific BSPs and kernel features, but for the meta-xilinx targets it uses the http://git.yoctoproject.org/cgit/cgit.cgi/linux-yocto-4.12/log/?h=standard/base branch, which is essentially mainline. You can also use the linux-yocto-dev kernel which moves but currently points at 4.15-rc1, http://git.yoctoproject.org/cgit/cgit.cgi/linux-yocto-dev/. Or you can use your own kernel recipe, of which could be mainline at what ever version desired. You can select the kernel recipe by setting "PREFERRED_PROVIDER_virtual/kernel", and the version by "PREFERRED_VERSION_" (where kernel-name is the name of the kernel recipe e.g. linux-xlnx). > > Sorry for asking so many questions, I am trying to make a point within my > organisation that > it is worth using Yocto. But they are holding against me that the Xilinx > kernel would contain > patches which are not accepted yet in the upstream kernel, and which would > present risks in > using a Xilinx kernel with AARCH64 RPMs from another disctribution (in our > case CentOS) - > which is actually what I am really after: I would like to have my Zynqs > running with other > software already developed in my organisation. Some OE users take RPMs from external sources and populate them into their images with OE, you could do that. Though there are considerations you would need to make with regards to dependencies and compatibility (e.g. libc) of the external packages. Regards, Nathan > > Thanks for any help with mu issue. > > Cheers, >Ralf. > > > PS: I signed up with the meta-xilinx mailing list many times, but never got > a confirmation > message. Is this normal? > > > On 12/13/2017 07:29 AM, Mike Looijmans wrote: >> >> On 12-12-17 16:20, Ralf Spiwoks wrote: >>> >>> Hello! >>> >>> I am using Yocto and meta-xilinx to build the Linux kernel 4.9 for >>> a Zynq XC7Z030. Now, in my organization some people said that: >>> >>> "Xilinx currently runs a custom Linux distribution which ... has patches >>> to the kernel by Xilink which are not accepted yet in the upstream Linux >>> kernel." >>> >>> So, my question is: >>> What are the differences of the Xilinx Linux kernel w.r.t. to the Linux >>> kernel >>> (from kernel.org)? >> >> >> The main difference is the support for dual-parallel QSPI flash memory. >> The driver for that is in a state (and has been for years) that apparently >> cannot be upstreamed. >> >> So if your board doesn't have dual flash, I'd recommend using mainline >> Linux instead. >> >> >> Kind regards, >> >> Mike Looijmans >> System Expert >> >> TOPIC Products >> Materiaalweg 4, NL-5681 RJ Best >> Postbus 440, NL-5680 AK Best >> Telefoon: +31 (0) 499 33 69 79 >> E-mail: mike.looijm...@topicproducts.com >> Website: www.topicproducts.com >> >> Please consider the environment before printing this e-mail >> >> >> >> > -- > ___ > meta-xilinx mailing list > meta-xilinx@yoctoproject.org > https://lists.yoctoproject.org/listinfo/meta-xilinx -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
Re: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
Dear Sandeep and Mike, Thank you very much for your replies. I am not using video nor dual-parallel QSPI flash memory. But I need the Xilinx DMA driver. Is that a consistent part of the mainline Linux? Sorry, but I simply don't know where to look. And apart from the drivers, there a no patches of Xilinx to other parts of the kernel? Provocatively I might ask, why does Xilinx have a dedicated repository for the kernel in that case. Is it just for convenience? I am also wondering, why the meta-xilinx recipe for the kernel build is based on kernel 4.9 while the "regular" build in the same Yocto version is 4.12, or did I get something wrong. Sorry for asking so many questions, I am trying to make a point within my organisation that it is worth using Yocto. But they are holding against me that the Xilinx kernel would contain patches which are not accepted yet in the upstream kernel, and which would present risks in using a Xilinx kernel with AARCH64 RPMs from another disctribution (in our case CentOS) - which is actually what I am really after: I would like to have my Zynqs running with other software already developed in my organisation. Thanks for any help with mu issue. Cheers, Ralf. PS: I signed up with the meta-xilinx mailing list many times, but never got a confirmation message. Is this normal? On 12/13/2017 07:29 AM, Mike Looijmans wrote: On 12-12-17 16:20, Ralf Spiwoks wrote: Hello! I am using Yocto and meta-xilinx to build the Linux kernel 4.9 for a Zynq XC7Z030. Now, in my organization some people said that: "Xilinx currently runs a custom Linux distribution which ... has patches to the kernel by Xilink which are not accepted yet in the upstream Linux kernel." So, my question is: What are the differences of the Xilinx Linux kernel w.r.t. to the Linux kernel (from kernel.org)? The main difference is the support for dual-parallel QSPI flash memory. The driver for that is in a state (and has been for years) that apparently cannot be upstreamed. So if your board doesn't have dual flash, I'd recommend using mainline Linux instead. Kind regards, Mike Looijmans System Expert TOPIC Products Materiaalweg 4, NL-5681 RJ Best Postbus 440, NL-5680 AK Best Telefoon: +31 (0) 499 33 69 79 E-mail: mike.looijm...@topicproducts.com Website: www.topicproducts.com Please consider the environment before printing this e-mail -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
Re: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
On 12-12-17 16:20, Ralf Spiwoks wrote: Hello! I am using Yocto and meta-xilinx to build the Linux kernel 4.9 for a Zynq XC7Z030. Now, in my organization some people said that: "Xilinx currently runs a custom Linux distribution which ... has patches to the kernel by Xilink which are not accepted yet in the upstream Linux kernel." So, my question is: What are the differences of the Xilinx Linux kernel w.r.t. to the Linux kernel (from kernel.org)? The main difference is the support for dual-parallel QSPI flash memory. The driver for that is in a state (and has been for years) that apparently cannot be upstreamed. So if your board doesn't have dual flash, I'd recommend using mainline Linux instead. Kind regards, Mike Looijmans System Expert TOPIC Products Materiaalweg 4, NL-5681 RJ Best Postbus 440, NL-5680 AK Best Telefoon: +31 (0) 499 33 69 79 E-mail: mike.looijm...@topicproducts.com Website: www.topicproducts.com Please consider the environment before printing this e-mail -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
Re: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
Hi Ralf, AFAIK some of our video driver are not yet upstream so we have separate branches for video(2017.x_video_ea) and I assume this will be done in 2018.1 release. If you are using Zynq-7000 series devices everything should be upstream. Refer http://www.wiki.xilinx.com/Linux+Drivers these drivers are owned by Xilinx. Also you can refer http://www.wiki.xilinx.com/Linux%20Release%20Notes (2017.1-2017.4) for 4.9 driver patches submitted by Xilinx. Thanks, Sandeep -Original Message- From: meta-xilinx-boun...@yoctoproject.org [mailto:meta-xilinx-boun...@yoctoproject.org] On Behalf Of Ralf Spiwoks Sent: Tuesday, December 12, 2017 8:20 AM To: meta-xil...@lists.yoctoproject.org Subject: [meta-xilinx] Linux kernel differences between met-xilinx and kernel.org? Hello! I am using Yocto and meta-xilinx to build the Linux kernel 4.9 for a Zynq XC7Z030. Now, in my organization some people said that: "Xilinx currently runs a custom Linux distribution which ... has patches to the kernel by Xilink which are not accepted yet in the upstream Linux kernel." So, my question is: What are the differences of the Xilinx Linux kernel w.r.t. to the Linux kernel (from kernel.org)? With my best regards, Ralf Spiwoks, CERN -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
[meta-xilinx] Linux kernel differences between met-xilinx and kernel.org?
Hello! I am using Yocto and meta-xilinx to build the Linux kernel 4.9 for a Zynq XC7Z030. Now, in my organization some people said that: "Xilinx currently runs a custom Linux distribution which ... has patches to the kernel by Xilink which are not accepted yet in the upstream Linux kernel." So, my question is: What are the differences of the Xilinx Linux kernel w.r.t. to the Linux kernel (from kernel.org)? With my best regards, Ralf Spiwoks, CERN -- ___ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
