On Fri, Sep 17, 2021 at 5:57 AM Huacai Chen <chenhuacai@xxxxxxxxxxx>
wrote:> --- /dev/null
> +++ b/arch/loongarch/.gitignore
> @@ -0,0 +1,9 @@
> +*.lds
> +*.raw
> +calc_vmlinuz_load_addr
> +elf-entry
> +relocs
> +vmlinux.*
> +vmlinuz.*
> +
> +!kernel/vmlinux.lds.S
Can you double-check that 'make clean' and/or 'make mrproper' remove all the
generated files? This may already be the case, but I don't see how this is
done in your Makefile
> +
> +choice
> + prompt "Page Table Layout"
> + default 16KB_2LEVEL if 32BIT
> + default 16KB_3LEVEL if 64BIT
> + help
> + Allows choosing the page table layout, which is a combination
> + of page size and page table levels. The virtual memory address
> + space bits are determined by the page table layout.
> +
> +config 4KB_3LEVEL
> + bool "4KB with 3 levels"
> + select PAGE_SIZE_4KB
> + select PGTABLE_3LEVEL
> + help
> + This option selects 4KB page size with 3 level page tables, which
> + support a maximum 39 bits of application virtual memory.
> + ...
Nice, this choice statement looks a lot better than the version you had before.
> +
> +cflags-y += -ffreestanding
I had not noticed this previously, but I think this should not be used here,
as -ffreestanding disables a number of optimizations for compiler builtins.
Did you just copy this from MIPS or do you have a particular reason this
is used here?
> +# Some distribution-specific toolchains might pass the -fstack-check
> +# option during the build, which adds a simple stack-probe at the beginning
> +# of every function. This stack probe is to ensure that there is enough
> +# stack space, else a SEGV is generated. This is not desirable for LoongArch
> +# as kernel stacks are small, placed in unmapped virtual memory, and do not
> +# grow when overflowed.
> +#
> +cflags-y += -fno-stack-check
This is already set in the global Makefile and can be removed as well
> +cflags-y += $(call as-option,-Wa$(comma)-mno-fix-loongson3-llsc,)
> +cflags-y += -U_LOONGARCH_ISA -D_LOONGARCH_ISA=_LOONGARCH_ISA_LOONGARCH64
> +
> +load-y = 0x9000000000200000
> +
> +drivers-$(CONFIG_PCI) += arch/loongarch/pci/
> +
> +KBUILD_AFLAGS += $(cflags-y)
> +KBUILD_CFLAGS += $(cflags-y)
> +KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y)
> +
> +bootvars-y = VMLINUX_LOAD_ADDRESS=$(load-y) PLATFORM="$(platform-y)"
I would argue that VMLINUX_LOAD_ADDRESS should not be configurable
here, instead all kernels should use the same value.
> diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild
> new file mode 100644
> index 000000000000..41a76e675321
> --- /dev/null
> +++ b/arch/loongarch/include/asm/Kbuild
> @@ -0,0 +1,31 @@
> +# SPDX-License-Identifier: GPL-2.0
> +generic-y += dma-contiguous.h
> +generic-y += export.h
> +generic-y += mcs_spinlock.h
> +generic-y += parport.h
> +generic-y += early_ioremap.h
> +generic-y += qrwlock.h
> +generic-y += qspinlock.h
The list is apparently from an older kernel and no longer needed for
files that are listed in include/asm-generic/Kbuild.
Please only list the files that are not already there.
Arnd
