The variable 'KERNEL_ARCH' is actually a normalized version of
'ARCH'/'BR2_ARCH'. For example, 'arcle' and 'arceb' both become 'arc', just
as all powerpc variants become 'powerpc'.
It is presumably called 'KERNEL_ARCH' because the Linux kernel is typically
the first place where support for a new architecture is added, and thus is
the entity that defines the normalized name.
However, the term 'KERNEL_ARCH' can also be interpreted as 'the architecture
used by the kernel', which need not be exactly the same as 'the normalized
name for a certain arch'. In particular, for cases where a 64-bit
architecture is running a 64-bit kernel but 32-bit userspace. Examples
include:
* aarch64 architecture, with aarch64 kernel and 32-bit (ARM) userspace
* x86_64 architecture, with x86_64 kernel and 32-bit (i386) userspace
In such cases, the 'architecture used by the kernel' needs to refer to the
64-bit name (aarch64, x86_64), whereas all userspace applications need to
refer the, potentially normalized, 32-bit name.
This means that there need to be two different variables:
KERNEL_ARCH: the architecture used by the kernel
NORMALIZED_ARCH: the normalized name for the current userspace architecture
At this moment, both will actually have the same content. But a subsequent
patch will add basic support for situations described above, in which
KERNEL_ARCH may become overwritten to the 64-bit architecture, while
NORMALIZED_ARCH needs to remain the same (32-bit) case.
This commit replaces use of KERNEL_ARCH where actually the userspace arch is
needed. Places that use KERNEL_ARCH in combination with building of kernel
modules are not touched.
There may be cases where a package builds both a kernel module as userspace,
in which case it may need to know about both KERNEL_ARCH and
NORMALIZED_ARCH, for the case where they differ. But this is to be fixed on
a per-need basis.
Signed-off-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Reviewed-by: Romain Naour <romain.naour@gmail.com>
[Arnout: Also rename BR2_KERNEL_ARCH to BR2_NORMALIZED_ARCH]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Similar to other arch-specific strings, the 'KERNEL_ARCH' variable can be
determined from Config.in.<arch> files.
Besides aligning with similar strings, this also means simplification: the
big 'sed' covers several architectures not even supported by Buildroot.
Signed-off-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Reviewed-by: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
They are loosely ordered according to the ordering of the gcc
documentation. It is not entirely correct as the generic x86-64,
x86-64-v2, x86-64-v3 and x86-64-v4 are listed before i386 in the gcc
documentation, but this nevertheless gives a good explanation for the
overall ordering of the list.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
These were added in gcc 9.x. The goldmont, goldmont-plus and tremont
are for the low-power CPUs. While cascadelake and tigerlake are for
the high-end ones.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Both skylake and skylake-avx512 were added in gcc 6.x. According to
https://en.wikipedia.org/wiki/Skylake_(microarchitecture) the early
Skylake processors indeed did not have AVX512 support, while the later
ones did, hence the separate gcc options.
Due to this being the first CPU we support with AVX512, this commit
adds BR2_X86_CPU_HAS_AVX512.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
These were added in gcc commit
d3c11974032e21121a051d423a1d71097edf752f ("Use proper Intel processor
names for -march=/-mtune=") which was merged in gcc 4.9.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
In gcc commit d3c11974032e21121a051d423a1d71097edf752f ("Use proper
Intel processor names for -march=/-mtune="), which was merged in gcc
4.9, the following replacements were made:
* corei7 -> nehalem
* corei7-avx -> sandybridge
* core-avx-i -> ivybridge
* core-avx2 -> haswell
* atom -> bonnel
* slm -> silvermont
So this commit marks the Buildroot options BR2_x86_corei7,
BR2_x86_corei7_avx, BR2_x86_core_avx2 and BR2_x86_atom as deprecated,
and adds the four corresponding options with the newer names.
Note that the older options are still kept because the new option
names are only supported starting gcc 4.9, and we theoretically still
supports targets gcc as old as gcc 4.3.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
The BR2_ARCH definition is like this:
* i486 for the i486 platform
* i586 for a small number of platforms
* i686 for all other x86 platforms when used in 32-bit, but we
enumerate their entire list
* x86_64 for all x86 64-bit platforms
The list for i686 is long and needs to be extended everytime a new
platform is added, with no added value.
So this commit simplifies that by replacing this long list with just:
default "i686" if BR2_i386
This works because Kconfig guarantees us that if an i386 platform
matches an earlier case (i486 or one of the i586 platforms), the i486
and i586 earlier in the list will match.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
We already have support for a wide range of x86-64 CPUs, but we don't
have any option to build for the most generic possible x86-64 CPU, as
made available by the -march=x86-64 GCC option.
This commit makes this option available in Buildroot.
It only really makes sense to use as a 64-bit CPU, and not as a 32-bit
one, so we guard it behind BR2_x86_64.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
[yann.morin.1998@free.fr: it's an x86-64-only CPU]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
The westmere line of x86_64 targets lies between nehalem (corei7) and
sandybridge (corei7-avx). Allowing use of -march=westmere enables use of
AES instruction set on these targets.
Signed-off-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
It is too sad when an editor picks up the wrong syntax...
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
... to follow the convention: type, default, depends on, select, help.
Signed-off-by: Ricardo Martincoski <ricardo.martincoski@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
The old Atom target is not really fitting for recent Atom CPUs based
on Silvermont, Airmont or Goldmont. Those have more in common with
older Desktop CPUs than old Atoms.
Signed-off-by: Norbert Lange <norbert.lange@andritz.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
This config option corresponds to the string returned by readelf for
the "Machine" field of the ELF header. It will be used to check if the
architecture of binaries built by Buildroot match the target
architecture.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
We were not defining BR2_ARCH for two of the x86 subarchitecture,
which means the architecture part of the GNU_TARGET_NAME tuple was
empty, leading to weird build failures.
This commit fixes that by defining the appropriate values.
Fixes bug #8861.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
The Linux kernel doesn't even support i386 anymore, there is no NPTL
support for i386 and uClibc-ng only supports NPTL on x86, so there is
essentially no usable thread implementation. Most likely glibc and
musl also don't support i386 either. So it's time to remove the
support for this architecture variant.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Now that BR2_ARCH_HAS_ATOMICS is no longer used anywhere, we can
remove it from arch/Config.in*, as well as from the documentation.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
The Intel X1000 is the Pentium class microprocessor that ships with
Galileo Gen 1/2. This patch adds changes to arch and toolchain-wrapper
to omit the lock prefix for the X1000.
[Thomas: tweak commit log and Config.in help text.]
Signed-off-by: Ray Kinsella <ray.kinsella@intel.com>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Add support for AMD steamroller optimizations, available in gcc 4.8+ as
bdver3.
Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
The fuzzy generic x86 variant doesn't make much sense in the context of
Buildroot, and the recent change to use -march instead of -mtune broke it.
From the GCC manual:
https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/i386-and-x86-64-Options.html#i386-and-x86-64-Options:
-mtune=cpu-type
Tune to cpu-type everything applicable about the generated code,
except for the ABI and the set of available instructions. While
picking a specific cpu-type schedules things appropriately for that
particular chip, the compiler does not generate any code that cannot
run on the default machine type unless you use a -march=cpu-type
option. For example, if GCC is configured for i686-pc-linux-gnu then
-mtune=pentium4 generates code that is tuned for Pentium 4 but still
runs on i686 machines.
The choices for cpu-type are the same as for -march. In addition,
-mtune supports 2 extra choices for cpu-type:
‘generic’
Produce code optimized for the most common IA32/AMD64/EM64T
processors. If you know the CPU on which your code will run,
then you should use the corresponding -mtune or -march option
instead of -mtune=generic. But, if you do not know exactly what
CPU users of your application will have, then you should use
this option.
As new processors are deployed in the marketplace, the behavior
of this option will change. Therefore, if you upgrade to a newer
version of GCC, code generation controlled by this option will
change to reflect the processors that are most common at the
time that version of GCC is released.
There is no -march=generic option because -march indicates the
instruction set the compiler can use, and there is no generic
instruction set applicable to all processors. In contrast,
-mtune indicates the processor (or, in this case, collection of
processors) for which the code is optimized.
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
According to the gcc documentation, -march implies -mtune on x86, so
defining both BR2_GCC_TARGET_ARCH and BR2_GCC_TARGET_TUNE is
redundant. Therefore, this commit removes the definition of
BR2_GCC_TARGET_TUNE on x86.
However, while doing so, it adds one new case for BR2_GCC_TARGET_ARCH:
using -march=generic when BR2_x86_generic is selected.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Anton Kolesov <Anton.Kolesov@synopsys.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
gcc support was added in version 4.6:
http://gcc.gnu.org/gcc-4.6/changes.html
Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
This follow-up commit adds support for SSE 4 and SSE 4.2 to
the jaguar architecture.
Signed-off-by: Adrien Béraud <adrien.beraud@savoirfairelinux.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
AMD Jaguar ( https://en.wikipedia.org/wiki/Jaguar_%28microarchitecture%29 ) is
suddenly a popular architecture since it is used in the PS4 and the XBox One.
Many embedded systems are also likely to use it in the next years.
This patch adds support for GCC architecture-specific optimisations and
tuning for these CPUs.
These optimizations are available with GCC 4.8+.
Signed-off-by: Adrien Beraud <adrien.beraud@savoirfairelinux.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Suggested by Yann E. Morin.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reported-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
As suggested by Yann E. Morin, there is a better way than our current
big Config.in.common to define the gcc mtune, mcpu, march,
etc. values. We can split the setting of those values in each
architecture file, which makes a lot more sense.
Therefore, the Config.in file now creates empty kconfig variables
BR2_ARCH, BR2_ENDIAN, BR2_GCC_TARGET_TUNE, BR2_GCC_TARGET_ARCH,
BR2_GCC_TARGET_ABI and BR2_GCC_TARGET_CPU. The values of those
variables are set by the individual Config.in.<arch> files. This is
possible because such files are now only conditionally included
depending on the top-level architecture that has been selected.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
target/Config.in.arch had become too long, and we want to remove the
target/ directory. So let's move it to arch/ and split it this way:
* An initial Config.in that lists the top-level architecture, and
sources the arch-specific Config.in.<arch> files, as well as
Config.in.common (see below)
* One Config.in.<arch> per architecture, listing the CPU families,
ABI choices, etc.
* One Config.in.common that defines the gcc mtune, march, mcpu values
and other hidden options.
[Peter: space->tab fix, mipsel64 little endian, mips3 as noted by Arnout]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
