by Huacai Chen

[permalink] [raw]

Subject: Re: [PATCH V11 00/22] arch: Add basic LoongArch support

Hi, Arnd,

On Wed, May 18, 2022 at 9:42 PM Arnd Bergmann <[email protected]> wrote:
>
> On Wed, May 18, 2022 at 10:25 AM Huacai Chen <[email protected]> wrote:
> >
> > LoongArch is a new RISC ISA, which is a bit like MIPS or RISC-V.
> > LoongArch includes a reduced 32-bit version (LA32R), a standard 32-bit
> > version (LA32S) and a 64-bit version (LA64). LoongArch use ACPI as its
> > boot protocol LoongArch-specific interrupt controllers (similar to APIC)
> > are already added in the next revision of ACPI Specification (current
> > revision is 6.4).
> >
> > This patchset is adding basic LoongArch support in mainline kernel, we
> > can see a complete snapshot here:
> > https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-next
>
> Stephen, can you add this branch to the linux-next tree?
>
> I see there are still comments coming in, but at some point this has
> to just be considered good enough that any further changes can be addressed
> with patches on top rather than rebasing.
>
> > V10 -> V11:
> > 1, Rebased on asm-generic tree;
>
> I was expecting that you'd base this on just the spinlock changes from Palmer's
> tree that are part of the asm-generic tree rather than all of what I have.
>
> Can you rebase it once more? If there are conflicts against the h8300 removal
> series that is also in asm-generic, leaving it on top of that may be
> easier though.
Thank you very much, I have rebased the below tree on asm-generic
tree's spinlock commit 9282d0996936c5fbf877c0d096a3feb45 again, and
fixed some small problems from Eric and WANG Xuerui's comments in V11.
https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-next

Huacai
>
> Arnd

2022-05-18 22:58:50

Reviewed-by: Guo Ren <[email protected]>

On Wed, May 18, 2022 at 5:32 PM Huacai Chen <[email protected]> wrote:
>
> Add Kbuild, Makefile, Kconfig and link script for LoongArch build
> infrastructure.
>
> Signed-off-by: Huacai Chen <[email protected]>
> ---
> arch/loongarch/Kbuild | 6 +
> arch/loongarch/Kconfig | 395 +++++++++++++++++++++++++
> arch/loongarch/Kconfig.debug | 0
> arch/loongarch/Makefile | 105 +++++++
> arch/loongarch/boot/.gitignore | 2 +
> arch/loongarch/boot/Makefile | 20 ++
> arch/loongarch/boot/dts/Makefile | 4 +
> arch/loongarch/include/asm/Kbuild | 30 ++
> arch/loongarch/include/uapi/asm/Kbuild | 2 +
> arch/loongarch/kernel/.gitignore | 2 +
> arch/loongarch/kernel/Makefile | 21 ++
> arch/loongarch/kernel/vmlinux.lds.S | 117 ++++++++
> arch/loongarch/lib/Makefile | 6 +
> arch/loongarch/mm/Makefile | 9 +
> arch/loongarch/pci/Makefile | 7 +
> arch/loongarch/vdso/.gitignore | 2 +
> scripts/subarch.include | 2 +-
> 17 files changed, 729 insertions(+), 1 deletion(-)
> create mode 100644 arch/loongarch/Kbuild
> create mode 100644 arch/loongarch/Kconfig
> create mode 100644 arch/loongarch/Kconfig.debug
> create mode 100644 arch/loongarch/Makefile
> create mode 100644 arch/loongarch/boot/.gitignore
> create mode 100644 arch/loongarch/boot/Makefile
> create mode 100644 arch/loongarch/boot/dts/Makefile
> create mode 100644 arch/loongarch/include/asm/Kbuild
> create mode 100644 arch/loongarch/include/uapi/asm/Kbuild
> create mode 100644 arch/loongarch/kernel/.gitignore
> create mode 100644 arch/loongarch/kernel/Makefile
> create mode 100644 arch/loongarch/kernel/vmlinux.lds.S
> create mode 100644 arch/loongarch/lib/Makefile
> create mode 100644 arch/loongarch/mm/Makefile
> create mode 100644 arch/loongarch/pci/Makefile
> create mode 100644 arch/loongarch/vdso/.gitignore
>
> diff --git a/arch/loongarch/Kbuild b/arch/loongarch/Kbuild
> new file mode 100644
> index 000000000000..ab5373d0a24f
> --- /dev/null
> +++ b/arch/loongarch/Kbuild
> @@ -0,0 +1,6 @@
> +obj-y += kernel/
> +obj-y += mm/
> +obj-y += vdso/
> +
> +# for cleaning
> +subdir- += boot
> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> new file mode 100644
> index 000000000000..09902903bba8
> --- /dev/null
> +++ b/arch/loongarch/Kconfig
> @@ -0,0 +1,395 @@
> +# SPDX-License-Identifier: GPL-2.0
> +config LOONGARCH
> + bool
> + default y
> + select ACPI_MCFG if ACPI
> + select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
> + select ARCH_BINFMT_ELF_STATE
> + select ARCH_ENABLE_MEMORY_HOTPLUG
> + select ARCH_ENABLE_MEMORY_HOTREMOVE
> + select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
> + select ARCH_HAS_PTE_SPECIAL
> + select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> + select ARCH_INLINE_READ_LOCK if !PREEMPTION
> + select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
> + select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
> + select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
> + select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
> + select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
> + select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
> + select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
> + select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
> + select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
> + select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
> + select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
> + select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
> + select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
> + select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
> + select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
> + select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
> + select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
> + select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
> + select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
> + select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
> + select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
> + select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
> + select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
> + select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
> + select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
> + select ARCH_MIGHT_HAVE_PC_PARPORT
> + select ARCH_MIGHT_HAVE_PC_SERIO
> + select ARCH_SPARSEMEM_ENABLE
> + select ARCH_SUPPORTS_ACPI
> + select ARCH_SUPPORTS_ATOMIC_RMW
> + select ARCH_SUPPORTS_HUGETLBFS
> + select ARCH_USE_BUILTIN_BSWAP
> + select ARCH_USE_CMPXCHG_LOCKREF
> + select ARCH_USE_QUEUED_RWLOCKS
> + select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
> + select ARCH_WANTS_NO_INSTR
> + select BUILDTIME_TABLE_SORT
> + select COMMON_CLK
> + select GENERIC_CLOCKEVENTS
> + select GENERIC_CMOS_UPDATE
> + select GENERIC_CPU_AUTOPROBE
> + select GENERIC_ENTRY
> + select GENERIC_FIND_FIRST_BIT
> + select GENERIC_GETTIMEOFDAY
> + select GENERIC_IRQ_MULTI_HANDLER
> + select GENERIC_IRQ_PROBE
> + select GENERIC_IRQ_SHOW
> + select GENERIC_LIB_ASHLDI3
> + select GENERIC_LIB_ASHRDI3
> + select GENERIC_LIB_CMPDI2
> + select GENERIC_LIB_LSHRDI3
> + select GENERIC_LIB_UCMPDI2
> + select GENERIC_PCI_IOMAP
> + select GENERIC_SCHED_CLOCK
> + select GENERIC_TIME_VSYSCALL
> + select GPIOLIB
> + select HAVE_ARCH_AUDITSYSCALL
> + select HAVE_ARCH_COMPILER_H
> + select HAVE_ARCH_MMAP_RND_BITS if MMU
> + select HAVE_ARCH_SECCOMP_FILTER
> + select HAVE_ARCH_TRACEHOOK
> + select HAVE_ARCH_TRANSPARENT_HUGEPAGE
> + select HAVE_ASM_MODVERSIONS
> + select HAVE_CONTEXT_TRACKING
> + select HAVE_COPY_THREAD_TLS
> + select HAVE_DEBUG_KMEMLEAK
> + select HAVE_DEBUG_STACKOVERFLOW
> + select HAVE_DMA_CONTIGUOUS
> + select HAVE_EXIT_THREAD
> + select HAVE_FAST_GUP
> + select HAVE_GENERIC_VDSO
> + select HAVE_IOREMAP_PROT
> + select HAVE_IRQ_EXIT_ON_IRQ_STACK
> + select HAVE_IRQ_TIME_ACCOUNTING
> + select HAVE_MEMBLOCK
> + select HAVE_MEMBLOCK_NODE_MAP
> + select HAVE_MOD_ARCH_SPECIFIC
> + select HAVE_NMI
> + select HAVE_PCI
> + select HAVE_PERF_EVENTS
> + select HAVE_REGS_AND_STACK_ACCESS_API
> + select HAVE_RSEQ
> + select HAVE_SYSCALL_TRACEPOINTS
> + select HAVE_TIF_NOHZ
> + select HAVE_VIRT_CPU_ACCOUNTING_GEN
> + select IRQ_FORCED_THREADING
> + select IRQ_LOONGARCH_CPU
> + select MODULES_USE_ELF_RELA if MODULES
> + select OF
> + select OF_EARLY_FLATTREE
> + select PCI
> + select PCI_DOMAINS_GENERIC
> + select PCI_ECAM if ACPI
> + select PCI_MSI_ARCH_FALLBACKS
> + select PERF_USE_VMALLOC
> + select RTC_LIB
> + select SPARSE_IRQ
> + select SYSCTL_EXCEPTION_TRACE
> + select SWIOTLB
> + select TRACE_IRQFLAGS_SUPPORT
> + select ZONE_DMA32
> +
> +config 32BIT
> + bool
> +
> +config 64BIT
> + def_bool y
> +
> +config CPU_HAS_FPU
> + bool
> + default y
> +
> +config CPU_HAS_PREFETCH
> + bool
> + default y
> +
> +config GENERIC_CALIBRATE_DELAY
> + def_bool y
> +
> +config GENERIC_CSUM
> + def_bool y
> +
> +config GENERIC_HWEIGHT
> + def_bool y
> +
> +config L1_CACHE_SHIFT
> + int
> + default "6"
> +
> +config LOCKDEP_SUPPORT
> + bool
> + default y
> +
> +# MACH_LOONGSON32 and MACH_LOONGSON64 are delibrately carried over from the
> +# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that
> +# are shared between architectures, and specifically expecting the symbols.
> +config MACH_LOONGSON32
> + def_bool 32BIT
> +
> +config MACH_LOONGSON64
> + def_bool 64BIT
> +
> +config PAGE_SIZE_4KB
> + bool
> +
> +config PAGE_SIZE_16KB
> + bool
> +
> +config PAGE_SIZE_64KB
> + bool
> +
> +config PGTABLE_2LEVEL
> + bool
> +
> +config PGTABLE_3LEVEL
> + bool
> +
> +config PGTABLE_4LEVEL
> + bool
> +
> +config PGTABLE_LEVELS
> + int
> + default 2 if PGTABLE_2LEVEL
> + default 3 if PGTABLE_3LEVEL
> + default 4 if PGTABLE_4LEVEL
> +
> +config SCHED_OMIT_FRAME_POINTER
> + bool
> + default y
> +
> +menu "Kernel type and options"
> +
> +source "kernel/Kconfig.hz"
> +
> +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 size of virtual memory
> + address space 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 of 39 bits of application virtual memory.
> +
> +config 4KB_4LEVEL
> + bool "4KB with 4 levels"
> + select PAGE_SIZE_4KB
> + select PGTABLE_4LEVEL
> + help
> + This option selects 4KB page size with 4 level page tables, which
> + support a maximum of 48 bits of application virtual memory.
> +
> +config 16KB_2LEVEL
> + bool "16KB with 2 levels"
> + select PAGE_SIZE_16KB
> + select PGTABLE_2LEVEL
> + help
> + This option selects 16KB page size with 2 level page tables, which
> + support a maximum of 36 bits of application virtual memory.
> +
> +config 16KB_3LEVEL
> + bool "16KB with 3 levels"
> + select PAGE_SIZE_16KB
> + select PGTABLE_3LEVEL
> + help
> + This option selects 16KB page size with 3 level page tables, which
> + support a maximum of 47 bits of application virtual memory.
> +
> +config 64KB_2LEVEL
> + bool "64KB with 2 levels"
> + select PAGE_SIZE_64KB
> + select PGTABLE_2LEVEL
> + help
> + This option selects 64KB page size with 2 level page tables, which
> + support a maximum of 42 bits of application virtual memory.
> +
> +config 64KB_3LEVEL
> + bool "64KB with 3 levels"
> + select PAGE_SIZE_64KB
> + select PGTABLE_3LEVEL
> + help
> + This option selects 64KB page size with 3 level page tables, which
> + support a maximum of 55 bits of application virtual memory.
> +
> +endchoice
> +
> +config CMDLINE
> + string "Built-in kernel command line"
> + help
> + For most platforms, the arguments for the kernel's command line
> + are provided at run-time, during boot. However, there are cases
> + where either no arguments are being provided or the provided
> + arguments are insufficient or even invalid.
> +
> + When that occurs, it is possible to define a built-in command
> + line here and choose how the kernel should use it later on.
> +
> +choice
> + prompt "Kernel command line type"
> + default CMDLINE_BOOTLOADER
> + help
> + Choose how the kernel will handle the provided built-in command
> + line.
> +
> +config CMDLINE_BOOTLOADER
> + bool "Use bootloader kernel arguments if available"
> + help
> + Prefer the command-line passed by the boot loader if available.
> + Use the built-in command line as fallback in case we get nothing
> + during boot. This is the default behaviour.
> +
> +config CMDLINE_EXTEND
> + bool "Use built-in to extend bootloader kernel arguments"
> + help
> + The command-line arguments provided during boot will be
> + appended to the built-in command line. This is useful in
> + cases where the provided arguments are insufficient and
> + you don't want to or cannot modify them.
> +
> +config CMDLINE_FORCE
> + bool "Always use the built-in kernel command string"
> + help
> + Always use the built-in command line, even if we get one during
> + boot. This is useful in case you need to override the provided
> + command line on systems where you don't have or want control
> + over it.
> +
> +endchoice
> +
> +config DMI
> + bool "Enable DMI scanning"
> + select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
> + default y
> + help
> + This enables SMBIOS/DMI feature for systems, and scanning of
> + DMI to identify machine quirks.
> +
> +config EFI
> + bool "EFI runtime service support"
> + select UCS2_STRING
> + select EFI_PARAMS_FROM_FDT
> + select EFI_RUNTIME_WRAPPERS
> + help
> + This enables the kernel to use EFI runtime services that are
> + available (such as the EFI variable services).
> +
> +config EFI_STUB
> + bool "EFI boot stub support"
> + default y
> + depends on EFI
> + select EFI_GENERIC_STUB
> + help
> + This kernel feature allows the kernel to be loaded directly by
> + EFI firmware without the use of a bootloader.
> +
> +config FORCE_MAX_ZONEORDER
> + int "Maximum zone order"
> + range 14 64 if PAGE_SIZE_64KB
> + default "14" if PAGE_SIZE_64KB
> + range 12 64 if PAGE_SIZE_16KB
> + default "12" if PAGE_SIZE_16KB
> + range 11 64
> + default "11"
> + help
> + The kernel memory allocator divides physically contiguous memory
> + blocks into "zones", where each zone is a power of two number of
> + pages. This option selects the largest power of two that the kernel
> + keeps in the memory allocator. If you need to allocate very large
> + blocks of physically contiguous memory, then you may need to
> + increase this value.
> +
> + This config option is actually maximum order plus one. For example,
> + a value of 11 means that the largest free memory block is 2^10 pages.
> +
> + The page size is not necessarily 4KB. Keep this in mind
> + when choosing a value for this option.
> +
> +config SECCOMP
> + bool "Enable seccomp to safely compute untrusted bytecode"
> + depends on PROC_FS
> + default y
> + help
> + This kernel feature is useful for number crunching applications
> + that may need to compute untrusted bytecode during their
> + execution. By using pipes or other transports made available to
> + the process as file descriptors supporting the read/write
> + syscalls, it's possible to isolate those applications in
> + their own address space using seccomp. Once seccomp is
> + enabled via /proc/<pid>/seccomp, it cannot be disabled
> + and the task is only allowed to execute a few safe syscalls
> + defined by each seccomp mode.
> +
> + If unsure, say Y. Only embedded should say N here.
> +
> +endmenu
> +
> +config ARCH_SELECT_MEMORY_MODEL
> + def_bool y
> +
> +config ARCH_FLATMEM_ENABLE
> + def_bool y
> +
> +config ARCH_SPARSEMEM_ENABLE
> + def_bool y
> + help
> + Say Y to support efficient handling of sparse physical memory,
> + for architectures which are either NUMA (Non-Uniform Memory Access)
> + or have huge holes in the physical address space for other reasons.
> + See <file:Documentation/vm/numa.rst> for more.
> +
> +config ARCH_ENABLE_THP_MIGRATION
> + def_bool y
> + depends on TRANSPARENT_HUGEPAGE
> +
> +config ARCH_MEMORY_PROBE
> + def_bool y
> + depends on MEMORY_HOTPLUG
> +
> +config MMU
> + bool
> + default y
> +
> +config ARCH_MMAP_RND_BITS_MIN
> + default 12
> +
> +config ARCH_MMAP_RND_BITS_MAX
> + default 18
> +
> +menu "Power management options"
> +
> +source "drivers/acpi/Kconfig"
> +
> +endmenu
> +
> +source "drivers/firmware/Kconfig"
> diff --git a/arch/loongarch/Kconfig.debug b/arch/loongarch/Kconfig.debug
> new file mode 100644
> index 000000000000..e69de29bb2d1
> diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile
> new file mode 100644
> index 000000000000..6dcc0495bec9
> --- /dev/null
> +++ b/arch/loongarch/Makefile
> @@ -0,0 +1,105 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Author: Huacai Chen <[email protected]>
> +# Copyright (C) 2020-2022 Loongson Technology Corporation Limited
> +
> +boot := arch/loongarch/boot
> +
> +ifndef CONFIG_EFI_STUB
> +KBUILD_IMAGE = $(boot)/vmlinux
> +else
> +KBUILD_IMAGE = $(boot)/vmlinux.efi
> +endif
> +
> +#
> +# Select the object file format to substitute into the linker script.
> +#
> +64bit-tool-archpref = loongarch64
> +32bit-bfd = elf32-loongarch
> +64bit-bfd = elf64-loongarch
> +32bit-emul = elf32loongarch
> +64bit-emul = elf64loongarch
> +
> +ifdef CONFIG_64BIT
> +tool-archpref = $(64bit-tool-archpref)
> +UTS_MACHINE := loongarch64
> +endif
> +
> +ifneq ($(SUBARCH),$(ARCH))
> + ifeq ($(CROSS_COMPILE),)
> + CROSS_COMPILE := $(call cc-cross-prefix, $(tool-archpref)-linux- $(tool-archpref)-linux-gnu- $(tool-archpref)-unknown-linux-gnu-)
> + endif
> +endif
> +
> +ifdef CONFIG_64BIT
> +ld-emul = $(64bit-emul)
> +cflags-y += -mabi=lp64s
> +endif
> +
> +cflags-y += -G0 -pipe -msoft-float
> +LDFLAGS_vmlinux += -G0 -static -n -nostdlib
> +KBUILD_AFLAGS_KERNEL += -Wa,-mla-global-with-pcrel
> +KBUILD_CFLAGS_KERNEL += -Wa,-mla-global-with-pcrel
> +KBUILD_AFLAGS_MODULE += -Wa,-mla-global-with-abs
> +KBUILD_CFLAGS_MODULE += -fplt -Wa,-mla-global-with-abs,-mla-local-with-abs
> +
> +cflags-y += -ffreestanding
> +cflags-y += $(call cc-option, -mno-check-zero-division)
> +
> +load-y = 0x9000000000200000
> +bootvars-y = VMLINUX_LOAD_ADDRESS=$(load-y)
> +
> +drivers-$(CONFIG_PCI) += arch/loongarch/pci/
> +
> +KBUILD_AFLAGS += $(cflags-y)
> +KBUILD_CFLAGS += $(cflags-y)
> +KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y)
> +
> +# This is required to get dwarf unwinding tables into .debug_frame
> +# instead of .eh_frame so we don't discard them.
> +KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
> +
> +# Don't emit unaligned accesses.
> +# Not all LoongArch cores support unaligned access, and as kernel we can't
> +# rely on others to provide emulation for these accesses.
> +KBUILD_CFLAGS += $(call cc-option,-mstrict-align)
> +
> +KBUILD_CFLAGS += -isystem $(shell $(CC) -print-file-name=include)
> +
> +KBUILD_LDFLAGS += -m $(ld-emul)
> +
> +ifdef CONFIG_LOONGARCH
> +CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \
> + egrep -vw '__GNUC_(MINOR_|PATCHLEVEL_)?_' | \
> + sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/" -e 's/\$$/&&/g')
> +endif
> +
> +head-y := arch/loongarch/kernel/head.o
> +
> +libs-y += arch/loongarch/lib/
> +libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
> +
> +ifeq ($(KBUILD_EXTMOD),)
> +prepare: vdso_prepare
> +vdso_prepare: prepare0
> + $(Q)$(MAKE) $(build)=arch/loongarch/vdso include/generated/vdso-offsets.h
> +endif
> +
> +PHONY += vdso_install
> +vdso_install:
> + $(Q)$(MAKE) $(build)=arch/loongarch/vdso $@
> +
> +all: $(KBUILD_IMAGE)
> +
> +$(KBUILD_IMAGE): vmlinux
> + $(Q)$(MAKE) $(build)=$(boot) $(bootvars-y) $@
> +
> +install:
> + $(Q)install -D -m 755 $(KBUILD_IMAGE) $(INSTALL_PATH)/vmlinux-$(KERNELRELEASE)
> + $(Q)install -D -m 644 .config $(INSTALL_PATH)/config-$(KERNELRELEASE)
> + $(Q)install -D -m 644 System.map $(INSTALL_PATH)/System.map-$(KERNELRELEASE)
> +
> +define archhelp
> + echo ' install - install kernel into $(INSTALL_PATH)'
> + echo
> +endef
> diff --git a/arch/loongarch/boot/.gitignore b/arch/loongarch/boot/.gitignore
> new file mode 100644
> index 000000000000..49423ee96ef3
> --- /dev/null
> +++ b/arch/loongarch/boot/.gitignore
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +vmlinux*
> diff --git a/arch/loongarch/boot/Makefile b/arch/loongarch/boot/Makefile
> new file mode 100644
> index 000000000000..b39d50a7a3df
> --- /dev/null
> +++ b/arch/loongarch/boot/Makefile
> @@ -0,0 +1,20 @@
> +#
> +# arch/loongarch/boot/Makefile
> +#
> +# Copyright (C) 2020-2022 Loongson Technology Corporation Limited
> +#
> +
> +drop-sections := .comment .note .options .note.gnu.build-id
> +strip-flags := $(addprefix --remove-section=,$(drop-sections)) -S
> +OBJCOPYFLAGS_vmlinux.efi := -O binary $(strip-flags)
> +
> +targets := vmlinux
> +quiet_cmd_strip = STRIP $@
> + cmd_strip = $(STRIP) -s -o $@ $<
> +
> +$(obj)/vmlinux: vmlinux FORCE
> + $(call if_changed,strip)
> +
> +targets += vmlinux.efi
> +$(obj)/vmlinux.efi: $(obj)/vmlinux FORCE
> + $(call if_changed,objcopy)
> diff --git a/arch/loongarch/boot/dts/Makefile b/arch/loongarch/boot/dts/Makefile
> new file mode 100644
> index 000000000000..5f1f55e911ad
> --- /dev/null
> +++ b/arch/loongarch/boot/dts/Makefile
> @@ -0,0 +1,4 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +dtstree := $(srctree)/$(src)
> +
> +dtb-y := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
> diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild
> new file mode 100644
> index 000000000000..83bc0681e72b
> --- /dev/null
> +++ b/arch/loongarch/include/asm/Kbuild
> @@ -0,0 +1,30 @@
> +# SPDX-License-Identifier: GPL-2.0
> +generic-y += dma-contiguous.h
> +generic-y += export.h
> +generic-y += parport.h
> +generic-y += early_ioremap.h
> +generic-y += qrwlock.h
> +generic-y += qrwlock_types.h
> +generic-y += spinlock.h
> +generic-y += spinlock_types.h
> +generic-y += rwsem.h
> +generic-y += segment.h
> +generic-y += user.h
> +generic-y += stat.h
> +generic-y += fcntl.h
> +generic-y += ioctl.h
> +generic-y += ioctls.h
> +generic-y += mman.h
> +generic-y += msgbuf.h
> +generic-y += sembuf.h
> +generic-y += shmbuf.h
> +generic-y += statfs.h
> +generic-y += socket.h
> +generic-y += sockios.h
> +generic-y += termios.h
> +generic-y += termbits.h
> +generic-y += poll.h
> +generic-y += param.h
> +generic-y += posix_types.h
> +generic-y += resource.h
> +generic-y += kvm_para.h
> diff --git a/arch/loongarch/include/uapi/asm/Kbuild b/arch/loongarch/include/uapi/asm/Kbuild
> new file mode 100644
> index 000000000000..4aa680ca2e5f
> --- /dev/null
> +++ b/arch/loongarch/include/uapi/asm/Kbuild
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +generic-y += kvm_para.h
> diff --git a/arch/loongarch/kernel/.gitignore b/arch/loongarch/kernel/.gitignore
> new file mode 100644
> index 000000000000..bbb90f92d051
> --- /dev/null
> +++ b/arch/loongarch/kernel/.gitignore
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +vmlinux.lds
> diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile
> new file mode 100644
> index 000000000000..e5a3b2fb9961
> --- /dev/null
> +++ b/arch/loongarch/kernel/Makefile
> @@ -0,0 +1,21 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Makefile for the Linux/LoongArch kernel.
> +#
> +
> +extra-y := head.o vmlinux.lds
> +
> +obj-y += cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \
> + traps.o irq.o idle.o process.o dma.o mem.o io.o reset.o switch.o \
> + elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o
> +
> +obj-$(CONFIG_ACPI) += acpi.o
> +obj-$(CONFIG_EFI) += efi.o
> +
> +obj-$(CONFIG_CPU_HAS_FPU) += fpu.o
> +
> +obj-$(CONFIG_MODULES) += module.o module-sections.o
> +
> +obj-$(CONFIG_PROC_FS) += proc.o
> +
> +CPPFLAGS_vmlinux.lds := $(KBUILD_CFLAGS)
> diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S
> new file mode 100644
> index 000000000000..7da4c4d7c50d
> --- /dev/null
> +++ b/arch/loongarch/kernel/vmlinux.lds.S
> @@ -0,0 +1,117 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#include <linux/sizes.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/thread_info.h>
> +
> +#define PAGE_SIZE _PAGE_SIZE
> +
> +/*
> + * Put .bss..swapper_pg_dir as the first thing in .bss. This will
> + * ensure that it has .bss alignment (64K).
> + */
> +#define BSS_FIRST_SECTIONS *(.bss..swapper_pg_dir)
> +
> +#include <asm-generic/vmlinux.lds.h>
> +#include "image-vars.h"
> +
> +/*
> + * Max avaliable Page Size is 64K, so we set SectionAlignment
> + * field of EFI application to 64K.
> + */
> +PECOFF_FILE_ALIGN = 0x200;
> +PECOFF_SEGMENT_ALIGN = 0x10000;
> +
> +OUTPUT_ARCH(loongarch)
> +ENTRY(kernel_entry)
> +PHDRS {
> + text PT_LOAD FLAGS(7); /* RWX */
> + note PT_NOTE FLAGS(4); /* R__ */
> +}
> +
> +jiffies = jiffies_64;
> +
> +SECTIONS
> +{
> + . = VMLINUX_LOAD_ADDRESS;
> +
> + _text = .;
> + HEAD_TEXT_SECTION
> +
> + . = ALIGN(PECOFF_SEGMENT_ALIGN);
> + .text : {
> + TEXT_TEXT
> + SCHED_TEXT
> + CPUIDLE_TEXT
> + LOCK_TEXT
> + KPROBES_TEXT
> + IRQENTRY_TEXT
> + SOFTIRQENTRY_TEXT
> + *(.fixup)
> + *(.gnu.warning)
> + } :text = 0
> + . = ALIGN(PECOFF_SEGMENT_ALIGN);
> + _etext = .;
> +
> + EXCEPTION_TABLE(16)
> +
> + . = ALIGN(PECOFF_SEGMENT_ALIGN);
> + __init_begin = .;
> + __inittext_begin = .;
> +
> + INIT_TEXT_SECTION(PAGE_SIZE)
> + .exit.text : {
> + EXIT_TEXT
> + }
> +
> + . = ALIGN(PECOFF_SEGMENT_ALIGN);
> + __inittext_end = .;
> +
> + __initdata_begin = .;
> +
> + INIT_DATA_SECTION(16)
> + .exit.data : {
> + EXIT_DATA
> + }
> +
> + .init.bss : {
> + *(.init.bss)
> + }
> + . = ALIGN(PECOFF_SEGMENT_ALIGN);
> + __initdata_end = .;
> +
> + __init_end = .;
> +
> + _sdata = .;
> + RO_DATA(4096)
> + RW_DATA(1 << CONFIG_L1_CACHE_SHIFT, PAGE_SIZE, THREAD_SIZE)
> +
> + .sdata : {
> + *(.sdata)
> + }
> + .edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGN); }
> + _edata = .;
> +
> + BSS_SECTION(0, SZ_64K, 8)
> + . = ALIGN(PECOFF_SEGMENT_ALIGN);
> +
> + _end = .;
> +
> + STABS_DEBUG
> + DWARF_DEBUG
> +
> + .gptab.sdata : {
> + *(.gptab.data)
> + *(.gptab.sdata)
> + }
> + .gptab.sbss : {
> + *(.gptab.bss)
> + *(.gptab.sbss)
> + }
> +
> + DISCARDS
> + /DISCARD/ : {
> + *(.gnu.attributes)
> + *(.options)
> + *(.eh_frame)
> + }
> +}
> diff --git a/arch/loongarch/lib/Makefile b/arch/loongarch/lib/Makefile
> new file mode 100644
> index 000000000000..e36635fccb69
> --- /dev/null
> +++ b/arch/loongarch/lib/Makefile
> @@ -0,0 +1,6 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Makefile for LoongArch-specific library files.
> +#
> +
> +lib-y += delay.o clear_user.o copy_user.o dump_tlb.o
> diff --git a/arch/loongarch/mm/Makefile b/arch/loongarch/mm/Makefile
> new file mode 100644
> index 000000000000..8ffc6383f836
> --- /dev/null
> +++ b/arch/loongarch/mm/Makefile
> @@ -0,0 +1,9 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Makefile for the Linux/LoongArch-specific parts of the memory manager.
> +#
> +
> +obj-y += init.o cache.o tlb.o tlbex.o extable.o \
> + fault.o ioremap.o maccess.o mmap.o pgtable.o page.o
> +
> +obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
> diff --git a/arch/loongarch/pci/Makefile b/arch/loongarch/pci/Makefile
> new file mode 100644
> index 000000000000..8101ef3df71c
> --- /dev/null
> +++ b/arch/loongarch/pci/Makefile
> @@ -0,0 +1,7 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Makefile for the PCI specific kernel interface routines under Linux.
> +#
> +
> +obj-y += pci.o
> +obj-$(CONFIG_ACPI) += acpi.o
> diff --git a/arch/loongarch/vdso/.gitignore b/arch/loongarch/vdso/.gitignore
> new file mode 100644
> index 000000000000..652e31d82582
> --- /dev/null
> +++ b/arch/loongarch/vdso/.gitignore
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +vdso.lds
> diff --git a/scripts/subarch.include b/scripts/subarch.include
> index 776849a3c500..4bd327d0ae42 100644
> --- a/scripts/subarch.include
> +++ b/scripts/subarch.include
> @@ -10,4 +10,4 @@ SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
> -e s/s390x/s390/ \
> -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
> -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
> - -e s/riscv.*/riscv/)
> + -e s/riscv.*/riscv/ -e s/loongarch.*/loongarch/)
> --
> 2.27.0
>

--
Best Regards
Guo Ren

ML: https://lore.kernel.org/linux-csky/