diff options
| author | Qi Hu <huqi@loongson.cn> | 2023-09-06 22:53:55 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2023-09-06 22:53:55 +0800 |
| commit | bd3c5798484aa9a08302a844d7a75a2ee3b53d05 (patch) | |
| tree | 338b637a5062d6a6e97b342691b2969a4ef3bd80 /arch/loongarch/kernel/process.c | |
| parent | f2091321044d9fbcadb93dfc1c9cf23e563ea40c (diff) | |
LoongArch: Add Loongson Binary Translation (LBT) extension support
Loongson Binary Translation (LBT) is used to accelerate binary translation,
which contains 4 scratch registers (scr0 to scr3), x86/ARM eflags (eflags)
and x87 fpu stack pointer (ftop).
This patch support kernel to save/restore these registers, handle the LBT
exception and maintain sigcontext.
Signed-off-by: Qi Hu <huqi@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch/kernel/process.c')
| -rw-r--r-- | arch/loongarch/kernel/process.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c index 4ee1e9d6a65f..91ccedd9db6a 100644 --- a/arch/loongarch/kernel/process.c +++ b/arch/loongarch/kernel/process.c @@ -38,6 +38,7 @@ #include <asm/cpu.h> #include <asm/elf.h> #include <asm/fpu.h> +#include <asm/lbt.h> #include <asm/io.h> #include <asm/irq.h> #include <asm/irq_regs.h> @@ -82,9 +83,11 @@ void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) euen = regs->csr_euen & ~(CSR_EUEN_FPEN); regs->csr_euen = euen; lose_fpu(0); + lose_lbt(0); clear_thread_flag(TIF_LSX_CTX_LIVE); clear_thread_flag(TIF_LASX_CTX_LIVE); + clear_thread_flag(TIF_LBT_CTX_LIVE); clear_used_math(); regs->csr_era = pc; regs->regs[3] = sp; @@ -121,10 +124,14 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) preempt_enable(); - if (used_math()) - memcpy(dst, src, sizeof(struct task_struct)); - else + if (!used_math()) memcpy(dst, src, offsetof(struct task_struct, thread.fpu.fpr)); + else + memcpy(dst, src, offsetof(struct task_struct, thread.lbt.scr0)); + +#ifdef CONFIG_CPU_HAS_LBT + memcpy(&dst->thread.lbt, &src->thread.lbt, sizeof(struct loongarch_lbt)); +#endif return 0; } @@ -189,8 +196,10 @@ out: ptrace_hw_copy_thread(p); clear_tsk_thread_flag(p, TIF_USEDFPU); clear_tsk_thread_flag(p, TIF_USEDSIMD); + clear_tsk_thread_flag(p, TIF_USEDLBT); clear_tsk_thread_flag(p, TIF_LSX_CTX_LIVE); clear_tsk_thread_flag(p, TIF_LASX_CTX_LIVE); + clear_tsk_thread_flag(p, TIF_LBT_CTX_LIVE); return 0; } |