This comment block was taken originally from the MIPS architecture code,
where indeed there are particular assumptions one can make regarding SMP
and !SMP and cycle counters. On LoongArch, however, the rdtime family of
functions is always available. As Xuerui wrote:
The rdtime family of instructions is in fact guaranteed to be
available on LoongArch; LoongArch's subsets all contain them, even
the 32-bit "Primary" subset intended for university teaching -- they
provide the rdtimeh.w and rdtimel.w pair of instructions that access
the same 64-bit counter.
So this commit simply removes the incorrect comment block.
Link: https://lore.kernel.org/lkml/e78940bc-9be2-2fe7-026f-9e64a1416c9f@xen0n.name/
Fixes: b738c106f7 ("LoongArch: Add other common headers")
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Commit c5febea095 ("fork: Pass struct kernel_clone_args into
copy_thread") change the prototype of copy_thread(), while commit
5bd2e97c86 ("fork: Generalize PF_IO_WORKER handling") change
the structure of kernel_clone_args. They cause build errors, so fix it.
Fixes: 5bd2e97c86 ("fork: Generalize PF_IO_WORKER handling")
Fixes: c5febea095 ("fork: Pass struct kernel_clone_args into copy_thread")
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
1, We assume arch/loongarch/include/asm/smp.h be included in include/
linux/smp.h is valid and the reverse inclusion isn't. So remove the
<linux/smp.h> in arch/loongarch/include/asm/smp.h.
2, arch/loongarch/include/asm/smp.h is only needed when CONFIG_SMP,
and setup.c include it only because it need plat_smp_setup(). So,
reorganize setup.c & smp.h, and then remove <asm/smp.h> in setup.c.
3, Fix cacheinfo.c and percpu.h build error by adding the missing header
files when !CONFIG_SMP.
4, Fix acpi.c build error by adding CONFIG_SMP guards.
5, Move irq_stat definition from smp.c to irq.c and fix its declaration.
6, Select CONFIG_SMP for CONFIG_NUMA, similar as other architectures do.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add Non-Uniform Memory Access (NUMA) support for LoongArch. LoongArch
has 48-bit physical address, but the HyperTransport I/O bus only support
40-bit address, so we need a custom phys_to_dma() and dma_to_phys() to
extract the 4-bit node id (bit 44~47) from Loongson-3's 48-bit physical
address space and embed it into 40-bit. In the 40-bit dma address, node
id offset can be read from the LS7A_DMA_CFG register.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LoongArch-based procesors have 4, 8 or 16 cores per package. This patch
adds multi-processor (SMP) support for LoongArch.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add VDSO and VSYSCALL support (sigreturn, gettimeofday and its friends)
for LoongArch.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add some misc common routines for LoongArch, including: asm-offsets
routines, futex functions, i/o memory access functions, frame-buffer
functions, procfs information display, etc.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add ucontext/sigcontext definition and signal handling support for
LoongArch.
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add system call support and related uaccess.h for LoongArch.
Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3:
A: The latest glibc release has some basic support for clone3 but it is
not complete. E.g., pthread_create() and spawni() have converted to
use clone3 but fork() will still use clone. Moreover, some seccomp
related applications can still not work perfectly with clone3. E.g.,
Chromium sandbox cannot work at all and there is no solution for it,
which is more terrible than the fork() story [1].
[1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add memory management support for LoongArch, including: cache and tlb
management, page fault handling and ioremap/mmap support.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add process management support for LoongArch, including: thread info
definition, context switch and process tracing.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add the exception and interrupt handling machanism for basic LoongArch
support.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add basic boot, setup and reset routines for LoongArch. Now, LoongArch
machines use UEFI-based firmware. The firmware passes configuration
information to the kernel via ACPI and DMI/SMBIOS.
Currently an existing interface between the kernel and the bootloader
is implemented. Kernel gets 2 values from the bootloader, passed in
registers a0 and a1; a0 is an "EFI boot flag" distinguishing UEFI and
non-UEFI firmware, while a1 is a pointer to an FDT with systable,
memmap, cmdline and initrd information.
The standard UEFI boot protocol (EFISTUB) will be added later.
Cc: linux-efi@vger.kernel.org
Cc: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Co-developed-by: Yun Liu <liuyun@loongson.cn>
Signed-off-by: Yun Liu <liuyun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add some other common headers for basic LoongArch support.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add common headers (atomic, bitops, barrier and locking) for basic
LoongArch support.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add common headers (CPU definition and address space layout) for basic
LoongArch support.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Jason A. Donenfeld