kumquat-buildroot/arch/Config.in.m68k

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config BR2_ARCH
default "m68k" if BR2_m68k
core: introduce NORMALIZED_ARCH as non-kernel replacement for KERNEL_ARCH 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>
2022-01-15 21:03:00 +01:00
config BR2_NORMALIZED_ARCH
default "m68k"
config BR2_ENDIAN
default "BIG"
# symbols used to distinguish between m68k and coldfire
# for gcc multilib
config BR2_m68k_m68k
bool
config BR2_m68k_cf
bool
# coldfire variants will be added later
choice
prompt "Target CPU"
default BR2_m68k_68040
depends on BR2_m68k
help
Specific CPU variant to use
config BR2_m68k_68040
bool "68040"
select BR2_m68k_m68k
arch: rework MMU option handling and move to "Target architecture" menu The MMU option is currently located in the "Toolchain" menu, but it doesn't make sense as it's really architecture related. In addition, the selection of MMU has an impact on the choice of binary format available, which is visible in the architecture menu. Therefore, this commit moves the MMU option into the architecture menu. However, if we simply move it in arch/Config.in, it means that we would have the following order of options: Target architecture Target architecture variant ABI MMU Binary format But really, the MMU option should be right below the Target architecture variant, and the available ABIs derived from that. The variant and ABI are arch-specfic, and defined in the per-arch Config.in fragments; a Kconfig option can have only one prompt defined, even under conditions, and appears at the place in the menu where its prompt was defined. So, there is no (easy) possibility to have a generic option appear where we want it. Since in fact only 2 architectures show a visible prompt for the MMU option (RISC-V and Xtensa), we move this option in arch/Config.in.riscv and arch/Config.in.xtensa. Some walkthrough the commit: - BR2_ARCH_HAS_MMU_MANDATORY and BR2_ARCH_HAS_MMU_OPTIONAL are removed as they are no longer needed - BR2_USE_MMU becomes a hidden boolean - All the places where we used to select BR2_ARCH_HAS_MMU_MANDATORY now select BR2_USE_MMU directly. - Introduce BR2_RISCV_USE_MMU and BR2_XTENSA_USE_MMU. - All defconfigs that used "# BR2_USE_MMU is not set" are switched to using the new option. All in all, this simplifies things quite a bit, and allows to have a good option ordering in the Target architecture menu. This commit might raise a concern in terms of backward compatibility with existing configurations. The only configurations that will be broken by this change are RISC-V noMMU (which was very recently introduced) and Xtensa noMMU (which we can probably agree is not such a widely popular configuration). Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> [yann.morin.1998@free.fr: - expand further why we need per-arch MMU options ] Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
2022-07-26 18:39:51 +02:00
select BR2_USE_MMU
config BR2_m68k_cf5208
bool "5208"
select BR2_m68k_cf
select BR2_SOFT_FLOAT
endchoice
config BR2_GCC_TARGET_CPU
default "68040" if BR2_m68k_68040
default "5208" if BR2_m68k_cf5208
config BR2_READELF_ARCH_NAME
default "MC68000"
# vim: ft=kconfig
# -*- mode:kconfig; -*-