Commit 13347c10 authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: entry: Add more common chores to EXCEPTION_PROLOGUE 



THe high level structure of most ARC exception handlers is
 1. save regfile with EXCEPTION_PROLOGUE
 2. setup r0: EFA (not part of pt_regs)
 3. setup r1: pointer to pt_regs (SP)
 4. drop down to pure kernel mode (from exception)
 5. call the Linux "C" handler

Remove the boiler plate code by moving #2, #3, #4 into #1.

The exceptions to most exceptions are syscall Trap and Machine check
which don't do some of above for various reasons, so call a newly
introduced variant EXCEPTION_PROLOGUE_KEEP_AE (same as original
EXCEPTION_PROLOGUE)

Tested-by: default avatarPavel Kozlov <Pavel.Kozlov@synopsys.com>
Signed-off-by: default avatarVineet Gupta <vgupta@kernel.org>
parent 0e93ecae

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

+11 −1
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ 
.endm



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

.macro EXCEPTION_PROLOGUE

.macro EXCEPTION_PROLOGUE_KEEP_AE



	; Before jumping to Exception Vector, hardware micro-ops did following:

	;   1. SP auto-switched to kernel mode stack
@@ -104,6 +104,16 @@ 
	; OUTPUT: r10 has ECR expected by EV_Trap

.endm



.macro EXCEPTION_PROLOGUE



	EXCEPTION_PROLOGUE_KEEP_AE	; return ECR in r10



	lr  r0, [efa]

	mov r1, sp



	FAKE_RET_FROM_EXCPN		; clobbers r9

.endm



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

 * This macro saves the registers manually which would normally be autosaved

 * by hardware on taken interrupts. It is used by

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

+11 −1
Original line number Diff line number Diff line
@@ -140,7 +140,7 @@ 
 *

 * After this it is safe to call the "C" handlers

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

.macro EXCEPTION_PROLOGUE

.macro EXCEPTION_PROLOGUE_KEEP_AE



	/* Need at least 1 reg to code the early exception prologue */

	PROLOG_FREEUP_REG r9, @ex_saved_reg1
@@ -179,6 +179,16 @@ 
	; OUTPUT: r10 has ECR expected by EV_Trap

.endm



.macro EXCEPTION_PROLOGUE



	EXCEPTION_PROLOGUE_KEEP_AE	; return ECR in r10



	lr  r0, [efa]

	mov r1, sp



	FAKE_RET_FROM_EXCPN		; clobbers r9

.endm



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

 * Restore all registers used by system call or Exceptions

 * SP should always be pointing to the next free stack element

arch/arc/kernel/entry-arcv2.S

+0 −15
Original line number Diff line number Diff line
@@ -125,11 +125,6 @@ ENTRY(mem_service) 


	EXCEPTION_PROLOGUE



	lr  r0, [efa]

	mov r1, sp



	FAKE_RET_FROM_EXCPN



	bl  do_memory_error

	b   ret_from_exception

END(mem_service)
@@ -138,11 +133,6 @@ ENTRY(EV_Misaligned) 


	EXCEPTION_PROLOGUE



	lr  r0, [efa]	; Faulting Data address

	mov r1, sp



	FAKE_RET_FROM_EXCPN



	SAVE_CALLEE_SAVED_USER

	mov r2, sp              ; callee_regs
@@ -163,11 +153,6 @@ ENTRY(EV_TLBProtV) 


	EXCEPTION_PROLOGUE



	lr  r0, [efa]	; Faulting Data address

	mov r1, sp	; pt_regs



	FAKE_RET_FROM_EXCPN



	mov blink, ret_from_exception

	b   do_page_fault

arch/arc/kernel/entry-compact.S

+0 −13
Original line number Diff line number Diff line
@@ -256,16 +256,6 @@ ENTRY(EV_TLBProtV) 


	EXCEPTION_PROLOGUE	; ECR returned in r10



	lr  r0, [efa]	; Faulting Data address (not part of pt_regs saved above)



	; Exception auto-disables further Intr/exceptions.

	; Re-enable them by pretending to return from exception

	; (so rest of handler executes in pure K mode)



	FAKE_RET_FROM_EXCPN



	mov   r1, sp	; Handle to pt_regs



	;------ (5) Type of Protection Violation? ----------

	;

	; ProtV Hardware Exception is triggered for Access Faults of 2 types
@@ -301,9 +291,6 @@ END(EV_TLBProtV) 
ENTRY(call_do_page_fault)



	EXCEPTION_PROLOGUE

	lr  r0, [efa]	; Faulting Data address

	mov   r1, sp

	FAKE_RET_FROM_EXCPN



	mov blink, ret_from_exception

	b  do_page_fault

arch/arc/kernel/entry.S

+2 −17
Original line number Diff line number Diff line
@@ -80,11 +80,6 @@ ENTRY(instr_service) 


	EXCEPTION_PROLOGUE



	lr  r0, [efa]

	mov r1, sp



	FAKE_RET_FROM_EXCPN



	bl  do_insterror_or_kprobe

	b   ret_from_exception

END(instr_service)
@@ -95,7 +90,7 @@ END(instr_service) 


ENTRY(EV_MachineCheck)



	EXCEPTION_PROLOGUE	; ECR returned in r10

	EXCEPTION_PROLOGUE_KEEP_AE	; ECR returned in r10



	lr  r0, [efa]

	mov r1, sp
@@ -128,11 +123,6 @@ ENTRY(EV_PrivilegeV) 


	EXCEPTION_PROLOGUE



	lr  r0, [efa]

	mov r1, sp



	FAKE_RET_FROM_EXCPN



	bl  do_privilege_fault

	b   ret_from_exception

END(EV_PrivilegeV)
@@ -144,11 +134,6 @@ ENTRY(EV_Extension) 


	EXCEPTION_PROLOGUE



	lr  r0, [efa]

	mov r1, sp



	FAKE_RET_FROM_EXCPN



	bl  do_extension_fault

	b   ret_from_exception

END(EV_Extension)
@@ -229,7 +214,7 @@ trap_with_param: 


ENTRY(EV_Trap)



	EXCEPTION_PROLOGUE

	EXCEPTION_PROLOGUE_KEEP_AE



	lr  r12, [efa]