Commit d4624bf6 authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARCv2: entry: rearrange pt_regs slightly 



Instead of r26,fp,sp,r12,r30 order as fp,r30,r12,r26,sp

 - keeps SP at well known position (right abive hardware autosave)
 - r26,r12 saved specifically for ARCv2 (and not in ARCv3) kept
   closer for easy ifdef'ry later

Signed-off-by: default avatarVineet Gupta <vgupta@kernel.org>
parent 656f18ad

arch/arc/include/asm/entry-arcv2.h

+6 −6
Original line number Diff line number Diff line
@@ -149,10 +149,10 @@ 
 */

.macro __SAVE_REGFILE_SOFT



	ST2	gp, fp, PT_r26		; gp (r26), fp (r27)



	st	r12, [sp, PT_r12]

	st	fp,  [sp, PT_fp]	; r27

	st	r30, [sp, PT_r30]

	st	r12, [sp, PT_r12]

	st	r26, [sp, PT_r26]	; gp



	; Saving pt_regs->sp correctly requires some extra work due to the way

	; Auto stack switch works
@@ -187,10 +187,10 @@ 
/*------------------------------------------------------------------------*/

.macro __RESTORE_REGFILE_SOFT



	LD2	gp, fp, PT_r26		; gp (r26), fp (r27)



	ld	r12, [sp, PT_r12]

	ld	fp,  [sp, PT_fp]

	ld	r30, [sp, PT_r30]

	ld	r12, [sp, PT_r12]

	ld	r26, [sp, PT_r26]



	; Restore SP (into AUX_USER_SP) only if returning to U mode

	;  - for K mode, it will be implicitly restored as stack is unwound

arch/arc/include/asm/ptrace.h

+5 −4
Original line number Diff line number Diff line
@@ -77,11 +77,10 @@ struct pt_regs { 


	unsigned long bta;	/* erbta */



	unsigned long r26;	/* gp */

	unsigned long fp;

	unsigned long sp;	/* user/kernel sp depending on where we came from  */



	unsigned long r12, r30;

	unsigned long r30;

	unsigned long r12;

	unsigned long r26;	/* gp */



#ifdef CONFIG_ARC_HAS_ACCL_REGS

	unsigned long r58, r59;	/* ACCL/ACCH used by FPU / DSP MPY */
@@ -90,6 +89,8 @@ struct pt_regs { 
	unsigned long DSP_CTRL;

#endif



	unsigned long sp;	/* user/kernel sp depending on entry  */



	/*------- Below list auto saved by h/w -----------*/

	unsigned long r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11;

arch/arc/kernel/asm-offsets.c

+4 −3
Original line number Diff line number Diff line
@@ -62,11 +62,9 @@ int main(void) 
	DEFINE(PT_r26, offsetof(struct pt_regs, r26));

	DEFINE(PT_ret, offsetof(struct pt_regs, ret));

	DEFINE(PT_blink, offsetof(struct pt_regs, blink));

	OFFSET(PT_fp, pt_regs, fp);

	DEFINE(PT_lpe, offsetof(struct pt_regs, lp_end));

	DEFINE(PT_lpc, offsetof(struct pt_regs, lp_count));

	DEFINE(SZ_CALLEE_REGS, sizeof(struct callee_regs));

	DEFINE(SZ_PT_REGS, sizeof(struct pt_regs));



#ifdef CONFIG_ISA_ARCV2

	OFFSET(PT_r12, pt_regs, r12);

	OFFSET(PT_r30, pt_regs, r30);
@@ -79,5 +77,8 @@ int main(void) 
	OFFSET(PT_DSP_CTRL, pt_regs, DSP_CTRL);

#endif



	DEFINE(SZ_CALLEE_REGS, sizeof(struct callee_regs));

	DEFINE(SZ_PT_REGS, sizeof(struct pt_regs));



	return 0;

}