5f959a1c61
This commit introduces the support for the EABIhf ABI, next to the existing support we have for EABI and OABI (even though OABI support is deprecated). EABIhf allows to improve performance of floating point workload by using floating point registers to transfer floating point arguments when calling functions, instead of using integer registers to do, as is done in the 'softfp' floating point model of EABI. In addition to this, this commit introduces a list of options for the floating point support: * Software floating point * VFP * VFPv3 * VFPv3-D16 * VFPv4 * VFPv4-D16 and it introduces some logic to make sure the options are only visible when it makes sense, depending on the ARM core being selected. This is however made complicated by the fact that certain VFP capabilities are mandatory on some cores, but optional on some other cores. The kconfig logic tries to achieve the following goals: * Hide options that are definitely not possible. * Use safe default values (i.e for Cortex-A5 and A7, the presence of the VFPv4 unit is optional, so we default on software floating point on these cores).. * Show the available possibilities, even if some of them are not necessarily working on a particular core (again, for the Cortex-A5 and A7 cores, there is no way of knowing whether the particular variant used by the user has VFPv4 or not, so we select software floating point by default, but still show VFP/VFPv3/VFPv4 options). It is worth noting that this commit doesn't add support for all possible -mfpu= values on ARM. We haven't added support for fpa, fpe2, fpe3, maverick (those four are only used on very old ARM cores), for vfpv3-fp16, vfpv3-d16-fp16, vfpv3xd, vfpv3xd-fp16, neon-fp16, vfpv4-sp-d16. They can be added quite easily if needed thanks to the new organization of the Config.in options. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> |
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| arch | ||
| board | ||
| boot | ||
| configs | ||
| docs | ||
| fs | ||
| linux | ||
| package | ||
| support | ||
| system | ||
| toolchain | ||
| .defconfig | ||
| .gitignore | ||
| CHANGES | ||
| Config.in | ||
| Config.in.legacy | ||
| COPYING | ||
| Makefile | ||
| Makefile.legacy | ||
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