From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Sun, 30 Dec 2018 16:11:20 +0100 Subject: [Buildroot] [PATCH 3/4] arch/arm: add armv8.2a cortex-based cores In-Reply-To: <4d7b62349a7cedd6d3762b39196a9069eb86297e.1546179362.git.yann.morin.1998@free.fr> References: <4d7b62349a7cedd6d3762b39196a9069eb86297e.1546179362.git.yann.morin.1998@free.fr> Message-ID: <20181230161120.23e57e35@windsurf> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Hello, On Sun, 30 Dec 2018 15:16:12 +0100, Yann E. MORIN wrote: > The armv8.2a generation is a cumulative extension to armv8.1a. > > Since gcc correctly enables the appropriate extensions based on the core > name, we don't really need to introduce a separate config for armv8.2a, > and we can piggyback on armv8a. > > In theory, gcc supports those cores in arm mode. However, configuring > gcc thusly generates a non-working gcc that constantly whines: > cc1: warning: switch -mcpu=cortex-a55 conflicts with -march=armv8.2-a switch > > It is to be noted that the -march flag is internal to gcc. It is not > something that Buildroot did set when configuring gcc; Buildroot only > ever sets --with-cpu (not --with-arch). > > Additionally, uClibc fails to build entirely (unsure if this is caused > by the above, or if it is a separate issue, though), with: > #### Your compiler does not support TLS and you are trying to build uClibc-ng > #### with NPTL support. Upgrade your binutils and gcc to versions which > #### support TLS for your architecture. Do not contact uClibc-ng maintainers > #### about this problem. > > Glibc and musl have not been tested in arm mode, so maybe we could have > a toolchain that eventually works (or at least, pretends to be working), > but we decided it was not worth the effort. > > Thus, we restrict those cores to AArch64 mode only. > > Signed-off-by: "Yann E. MORIN" > Cc: Thomas Petazzoni > > --- > Notes: those few packages that have a cortex-dependent option have been > checked to not require extending the list: at91bootstrap3, gst-omapfb, > kodi, nvidia-tegra23, and openblas. Only kvm-unit-tests may need it, but > it has not been done by lack of testing possibility. > --- > arch/Config.in.arm | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) Applied to master, thanks. Thomas -- Thomas Petazzoni, CTO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com