arch/riscv/kernel/suspend_entry.S

Source file repositories/reference/linux-study-clean/arch/riscv/kernel/suspend_entry.S

File Facts

System
Linux kernel
Corpus path
arch/riscv/kernel/suspend_entry.S
Extension
.S
Size
2489 bytes
Lines
94
Domain
Architecture Layer
Bucket
arch/riscv
Inferred role
Architecture Layer: arch/riscv
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 <linux/linkage.h>
#include <linux/cfi_types.h>
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/assembler.h>
#include <asm/csr.h>

	.text
	.altmacro
	.option norelax

SYM_FUNC_START(__cpu_suspend_enter)
	/* Save registers (except A0 and T0-T6) */
	REG_S	ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0)
	REG_S	sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0)
	REG_S	gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0)
	REG_S	tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0)
	REG_S	s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0)
	REG_S	s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0)
	REG_S	a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0)
	REG_S	a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0)
	REG_S	a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0)
	REG_S	a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0)
	REG_S	a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0)
	REG_S	a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0)
	REG_S	a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0)
	REG_S	s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0)
	REG_S	s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0)
	REG_S	s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0)
	REG_S	s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0)
	REG_S	s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0)
	REG_S	s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0)
	REG_S	s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0)
	REG_S	s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0)
	REG_S	s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0)
	REG_S	s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0)

	/* Save CSRs */
	csrr	t0, CSR_EPC
	REG_S	t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0)
	csrr	t0, CSR_STATUS
	REG_S	t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0)
	csrr	t0, CSR_TVAL
	REG_S	t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0)
	csrr	t0, CSR_CAUSE
	REG_S	t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0)

	/* Return non-zero value */
	li	a0, 1

	/* Return to C code */
	ret
SYM_FUNC_END(__cpu_suspend_enter)

SYM_TYPED_FUNC_START(__cpu_resume_enter)
	/* Load the global pointer */
	load_global_pointer

#ifdef CONFIG_MMU
	/* Save A0 and A1 */
	add	t0, a0, zero
	add	t1, a1, zero

	/* Enable MMU */
	la	a0, swapper_pg_dir
	call	relocate_enable_mmu

	/* Restore A0 and A1 */
	add	a0, t0, zero
	add	a1, t1, zero

Annotation

Implementation Notes