arch/sparc/kernel/etrap_64.S

Source file repositories/reference/linux-study-clean/arch/sparc/kernel/etrap_64.S

File Facts

System
Linux kernel
Corpus path
arch/sparc/kernel/etrap_64.S
Extension
.S
Size
7235 bytes
Lines
285
Domain
Architecture Layer
Bucket
arch/sparc
Inferred role
Architecture Layer: arch/sparc
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/asi.h>
#include <asm/pstate.h>
#include <asm/ptrace.h>
#include <asm/page.h>
#include <asm/spitfire.h>
#include <asm/head.h>
#include <asm/processor.h>
#include <asm/mmu.h>

#define		TASK_REGOFF		(THREAD_SIZE-TRACEREG_SZ-STACKFRAME_SZ)
#define		ETRAP_PSTATE1		(PSTATE_TSO | PSTATE_PRIV)
#define		ETRAP_PSTATE2		\
		(PSTATE_TSO | PSTATE_PEF | PSTATE_PRIV | PSTATE_IE)

/*
 * On entry, %g7 is return address - 0x4.
 * %g4 and %g5 will be preserved %l4 and %l5 respectively.
 */

		.text		
		.align	64
		.globl	etrap_syscall, etrap, etrap_irq, etraptl1
etrap:		rdpr	%pil, %g2
etrap_irq:	clr	%g3
etrap_syscall:	TRAP_LOAD_THREAD_REG(%g6, %g1)
		rdpr	%tstate, %g1
		or	%g1, %g3, %g1
		sllx	%g2, 20, %g3
		andcc	%g1, TSTATE_PRIV, %g0
		or	%g1, %g3, %g1
		bne,pn	%xcc, 1f
		 sub	%sp, STACKFRAME_SZ+TRACEREG_SZ-STACK_BIAS, %g2
661:		wrpr	%g0, 7, %cleanwin
		.section .fast_win_ctrl_1insn_patch, "ax"
		.word	661b
		.word	0x85880000	! allclean
		.previous

		sethi	%hi(TASK_REGOFF), %g2
		sethi	%hi(TSTATE_PEF), %g3
		or	%g2, %lo(TASK_REGOFF), %g2
		and	%g1, %g3, %g3
		brnz,pn	%g3, 1f
		 add	%g6, %g2, %g2
		wr	%g0, 0, %fprs
1:		rdpr	%tpc, %g3

		stx	%g1, [%g2 + STACKFRAME_SZ + PT_V9_TSTATE]
		rdpr	%tnpc, %g1
		stx	%g3, [%g2 + STACKFRAME_SZ + PT_V9_TPC]
		rd	%y, %g3
		stx	%g1, [%g2 + STACKFRAME_SZ + PT_V9_TNPC]
		rdpr	%tt, %g1
		st	%g3, [%g2 + STACKFRAME_SZ + PT_V9_Y]
		sethi	%hi(PT_REGS_MAGIC), %g3
		or	%g3, %g1, %g1
		st	%g1, [%g2 + STACKFRAME_SZ + PT_V9_MAGIC]

		rdpr	%cansave, %g1
		brnz,pt %g1, etrap_save
		 nop

		rdpr	%cwp, %g1
		add	%g1, 2, %g1
		wrpr	%g1, %cwp
		be,pt	%xcc, etrap_user_spill
		 mov	ASI_AIUP, %g3

		rdpr	%otherwin, %g3
		brz	%g3, etrap_kernel_spill

Annotation

Implementation Notes