On 27 April 2017 at 08:21, Manjukumar Harthikote Matha <manjukumar.harthikote-ma...@xilinx.com> wrote: > > >> -----Original Message----- >> From: Philip Balister [mailto:phi...@balister.org] >> Sent: Wednesday, April 26, 2017 12:38 PM >> To: Manjukumar Harthikote Matha <manju...@xilinx.com>; Nathan Rossi >> <nat...@nathanrossi.com> >> Cc: meta-xil...@lists.yoctoproject.org >> Subject: Re: [meta-xilinx] [PATCH] machine-xilinx-default.inc: Default to >> u-boot for >> Zynq >> >> On 04/26/2017 03:06 PM, Manjukumar Harthikote Matha wrote: >> > >> > >> >> -----Original Message----- >> >> From: Nathan Rossi [mailto:nat...@nathanrossi.com] >> >> Sent: Wednesday, April 26, 2017 10:54 AM >> >> To: Manjukumar Harthikote Matha <manju...@xilinx.com> >> >> Cc: meta-xil...@lists.yoctoproject.org >> >> Subject: Re: [meta-xilinx] [PATCH] machine-xilinx-default.inc: >> >> Default to u-boot for Zynq >> >> >> >> On 27 April 2017 at 02:41, Manjukumar Harthikote Matha >> >> <manjukumar.harthikote- ma...@xilinx.com> wrote: >> >>> >> >>> >> >>>> -----Original Message----- >> >>>> From: meta-xilinx-boun...@yoctoproject.org [mailto:meta-xilinx- >> >>>> boun...@yoctoproject.org] On Behalf Of Nathan Rossi >> >>>> Sent: Wednesday, April 26, 2017 4:57 AM >> >>>> To: meta-xil...@lists.yoctoproject.org >> >>>> Subject: [meta-xilinx] [PATCH] machine-xilinx-default.inc: Default >> >>>> to u-boot for Zynq >> >>>> >> >>>> Upstream U-Boot provides an almost complete environment for the >> >>>> majority of Zynq targets and specifically covers all the boot >> >>>> functionality required for the boards in the meta-xilinx layer. As >> >>>> such default to >> >> the mainline version of U-Boot. >> >>>> >> >>>> For users that require or prefer to use u-boot-xlnx this can be >> >>>> selected on a per- machine basis using: >> >>>> >> >>>> PREFERRED_PROVIDER_virtual/bootloader = "u-boot-xlnx" >> >>>> >> >>>> Signed-off-by: Nathan Rossi <nat...@nathanrossi.com> >> >>>> --- >> >>>> conf/machine/include/machine-xilinx-default.inc | 1 + >> >>>> 1 file changed, 1 insertion(+) >> >>>> >> >>>> diff --git a/conf/machine/include/machine-xilinx-default.inc >> >>>> b/conf/machine/include/machine-xilinx-default.inc >> >>>> index 13e4df5746..f9e7e3a33f 100644 >> >>>> --- a/conf/machine/include/machine-xilinx-default.inc >> >>>> +++ b/conf/machine/include/machine-xilinx-default.inc >> >>>> @@ -19,6 +19,7 @@ PREFERRED_VERSION_linux-xlnx ?= "4.6-xilinx-v2016.4%" >> >>>> >> >>>> # U-Boot Configuration >> >>>> XILINX_DEFAULT_UBOOT := "u-boot-xlnx" >> >>>> +XILINX_DEFAULT_UBOOT_zynq := "u-boot" >> >>>> XILINX_DEFAULT_UBOOT_zynqmp := "u-boot" >> >>> >> >>> Why have any preferred_provider? Distro can provide these settings. >> >>> For ex: meta-petalinux can provide u-boot-xlnx, oe-core can provide >> >>> u-boot >> >>> >> >>> Any thoughts? >> >> >> >> Unfortunately not picking a provider for "virtual/bootloader" will >> >> result in bitbake attempting to build all providers (since >> >> EXTRA_IMAGEDEPENDS is depending on virtual/bootloader), as bitbake >> >> has no idea which one is desired (and they are all compatible). >> >> >> >> -- >> >> NOTE: multiple providers are available for virtual/bootloader >> >> (u-boot-xlnx, u-boot- xlnx-dev, u-boot) >> >> NOTE: consider defining a PREFERRED_PROVIDER entry to match >> >> virtual/bootloader ... >> >> ERROR: Multiple .bb files are due to be built which each provide >> >> virtual/bootloader ... >> >> <various failures due to overlapping files/etc.> >> >> -- >> >> >> >> Also note, meta-petalinux or other layers should already be able to >> >> override this default (by setting with ??=) either in a distro conf >> >> or in a machine conf e.g. zynq- generic (for meta-petalinux). >> >> >> > If this is the case then why meta-xilinx should peg to upstream u-boot by >> > default? >> It should peg to u-boot-xlnx or linux-xlnx by default. We know that there are >> patches/drivers which are not upstreamed yet, and only available in Xilinx >> specific >> tree. This layer is specific to Xilinx updates and should stick to defaults >> supported by >> Xilinx. Other distros or layer stack which use meta-xilinx should override >> depending >> on their requirements not the other way round.
It should be noted that Xilinx does work with upstream U-Boot, since Xilinx has an active maintainer (and active contributors). I would call that support, but that is open to your own interpretation. >> > PREFERRED_PROVIDER_virtual/bootloader = "u-boot" should be specific to >> > boards >> other than the Xilinx eval boards, for example in zybo/microzed. >> >> I'd be happiest if meta-xilinx used upstream u-boot and a bbappend to add >> patches >> that are not upstream yet. This way we (the consumers) know exactly what the >> delta >> is to upstream. >> > Yes agreed on the methodology, that it would be the best if we maintained > patchset on top upstream master for u-boot or kernel. > But currently we don't have this model, and pinning down meta-xilinx to > upstream u-boot by default and not fetching Xilinx specific trees is not the > right answer as well. > meta-xilinx should ideally point to Xilinx trees, we have an option either > via distro or local.conf to change it to upstream at any given point. > We also can point certain evaluation boards (zybo/microzed/picozed etc) to > upstream u-boot or kernel. > >> In this day and age, using non-mainline u-boot and kernel leads to future >> pain. (Yes, I >> have some old pain from using linux-xlnx) > I agree, but certain drivers are not up-streamed and we are doing our best to > get them up-streamed. So the reason I have posted this patch for discussion is for this exact reason. Since u-boot v2017.01 (mainline), the majority of features and drivers are upstream (for zynq). The delta between xilinx/master (92e3dd638b50ad22dd90072673c80d8730903e95) and u-boot v2017.01 (which is the version in oe-core, as well as the base of the current xilinx/master) is very small for zynq. Looking at the differences, ignoring the obvious zynqmp/microblaze changes there are only a few features that are available in u-boot-xlnx that are not in mainline: * partial bitstream loading support * secure/encrypted bitstream loading support * support for rsa verification of images * board configs/devicetrees for various Xilinx internal boards Given that these features have very specific requirements, and that they rely on external Xilinx tools and software it is very unlikely that users are interested in these features by default when using meta-xilinx. The fact that the delta is almost gone for Zynq suggests that Xilinx has almost achieved that goal of fully upstreaming Zynq support. In my opinion at least, I think that the benefits of using mainline u-boot now greatly out weigh the benefits of u-boot-xlnx. As such I think now is the best time to make this switch. Regards, Nathan -- _______________________________________________ meta-xilinx mailing list meta-xilinx@yoctoproject.org https://lists.yoctoproject.org/listinfo/meta-xilinx
