arch/loongarch/kernel/entry.S

Source file repositories/reference/linux-study-clean/arch/loongarch/kernel/entry.S

File Facts

System
Linux kernel
Corpus path
arch/loongarch/kernel/entry.S
Extension
.S
Size
2106 bytes
Lines
102
Domain
Architecture Layer
Bucket
arch/loongarch
Inferred role
Architecture Layer: arch/loongarch
Status
atlas-only

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/loongarch.h>
#include <asm/regdef.h>
#include <asm/stackframe.h>
#include <asm/thread_info.h>
#include <asm/unwind_hints.h>

	.text
	.cfi_sections	.debug_frame
	.align	5
SYM_CODE_START(handle_syscall)
	UNWIND_HINT_UNDEFINED
	csrrd		t0, PERCPU_BASE_KS
	la.pcrel	t1, kernelsp
	PTR_ADD		t1, t1, t0
	move		t2, sp
	PTR_L		sp, t1, 0

	PTR_ADDI	sp, sp, -PT_SIZE
	cfi_st		t2, PT_R3
	cfi_rel_offset	sp, PT_R3
	LONG_S		zero, sp, PT_R0
	csrrd		t2, LOONGARCH_CSR_PRMD
	LONG_S		t2, sp, PT_PRMD
	csrrd		t2, LOONGARCH_CSR_CRMD
	LONG_S		t2, sp, PT_CRMD
	csrrd		t2, LOONGARCH_CSR_EUEN
	LONG_S		t2, sp, PT_EUEN
	csrrd		t2, LOONGARCH_CSR_ECFG
	LONG_S		t2, sp, PT_ECFG
	csrrd		t2, LOONGARCH_CSR_ESTAT
	LONG_S		t2, sp, PT_ESTAT
	cfi_st		ra, PT_R1
	cfi_st		a0, PT_R4
	cfi_st		a1, PT_R5
	cfi_st		a2, PT_R6
	cfi_st		a3, PT_R7
	cfi_st		a4, PT_R8
	cfi_st		a5, PT_R9
	cfi_st		a6, PT_R10
	cfi_st		a7, PT_R11
	csrrd		ra, LOONGARCH_CSR_ERA
	LONG_S		ra, sp, PT_ERA
	cfi_rel_offset	ra, PT_ERA

	cfi_st		tp, PT_R2
	cfi_st		u0, PT_R21
	cfi_st		fp, PT_R22

	SAVE_STATIC
	UNWIND_HINT_REGS

#ifdef CONFIG_KGDB
	li.w		t1, CSR_CRMD_WE
	csrxchg		t1, t1, LOONGARCH_CSR_CRMD
#endif

	move		u0, t0
	LONG_LI		tp, ~_THREAD_MASK
	and		tp, tp, sp

	move		a0, sp
	bl		do_syscall

	STACKLEAK_ERASE
	RESTORE_ALL_AND_RET
SYM_CODE_END(handle_syscall)
_ASM_NOKPROBE(handle_syscall)

Annotation

Implementation Notes