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Commit 28923f6b authored by Liav Rehana's avatar Liav Rehana Committed by Vineet Gupta
Browse files

ARC: [plat-eznps] handle extra aux regs #2: kernel/entry exit 



Preserve eflags and gpa1 aux during entry/exit into kernel as these
could be modified by kernel mode

These registers used by compare exchange instructions.
  - GPA1 is used for compare value,
  - EFLAGS got bit reflects atomic operation response.

EFLAGS is zeroed for each new user task so it won't get its
parent value.

Signed-off-by: default avatarLiav Rehana <liavr@mellanox.com>
Signed-off-by: default avatarNoam Camus <noamc@ezchip.com>
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 5b2189ab

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

+24 −0
Original line number Diff line number Diff line
@@ -192,6 +192,12 @@ 
	PUSHAX	lp_start

	PUSHAX	erbta



#ifdef CONFIG_ARC_PLAT_EZNPS

	.word CTOP_INST_SCHD_RW

	PUSHAX  CTOP_AUX_GPA1

	PUSHAX  CTOP_AUX_EFLAGS

#endif



	lr	r9, [ecr]

	st      r9, [sp, PT_event]    /* EV_Trap expects r9 to have ECR */

.endm
@@ -208,6 +214,12 @@ 
 * by hardware and that is not good.

 *-------------------------------------------------------------*/

.macro EXCEPTION_EPILOGUE

#ifdef CONFIG_ARC_PLAT_EZNPS

	.word CTOP_INST_SCHD_RW

	POPAX   CTOP_AUX_EFLAGS

	POPAX   CTOP_AUX_GPA1

#endif



	POPAX	erbta

	POPAX	lp_start

	POPAX	lp_end
@@ -265,6 +277,12 @@ 
	PUSHAX	lp_end

	PUSHAX	lp_start

	PUSHAX	bta_l\LVL\()



#ifdef CONFIG_ARC_PLAT_EZNPS

	.word CTOP_INST_SCHD_RW

	PUSHAX  CTOP_AUX_GPA1

	PUSHAX  CTOP_AUX_EFLAGS

#endif

.endm



/*--------------------------------------------------------------
@@ -277,6 +295,12 @@ 
 * by hardware and that is not good.

 *-------------------------------------------------------------*/

.macro INTERRUPT_EPILOGUE  LVL

#ifdef CONFIG_ARC_PLAT_EZNPS

	.word CTOP_INST_SCHD_RW

	POPAX   CTOP_AUX_EFLAGS

	POPAX   CTOP_AUX_GPA1

#endif



	POPAX	bta_l\LVL\()

	POPAX	lp_start

	POPAX	lp_end

arch/arc/include/asm/ptrace.h

+5 −0
Original line number Diff line number Diff line
@@ -19,6 +19,11 @@ 
#ifdef CONFIG_ISA_ARCOMPACT

struct pt_regs {



#ifdef CONFIG_ARC_PLAT_EZNPS

	unsigned long eflags;	/* Extended FLAGS */

	unsigned long gpa1;	/* General Purpose Aux */

#endif



	/* Real registers */

	unsigned long bta;	/* bta_l1, bta_l2, erbta */

arch/arc/kernel/process.c

+4 −0
Original line number Diff line number Diff line
@@ -234,6 +234,10 @@ void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp) 
	 */

	regs->status32 = STATUS_U_MASK | STATUS_L_MASK | ISA_INIT_STATUS_BITS;



#ifdef CONFIG_EZNPS_MTM_EXT

	regs->eflags = 0;

#endif



	/* bogus seed values for debugging */

	regs->lp_start = 0x10;

	regs->lp_end = 0x80;