Commit 5bd87adf authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: [ASID] Refactor the TLB paranoid debug code 



-Asm code already has values of SW and HW ASID values, so they can be
 passed to the printing routine.

Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent ade922f8

arch/arc/include/asm/mmu.h

+1 −1
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ typedef struct { 
} mm_context_t;



#ifdef CONFIG_ARC_DBG_TLB_PARANOIA

void tlb_paranoid_check(unsigned int pid_sw, unsigned long address);

void tlb_paranoid_check(unsigned int mm_asid, unsigned long address);

#else

#define tlb_paranoid_check(a, b)

#endif

arch/arc/mm/tlb.c

+13 −11
Original line number Diff line number Diff line
@@ -688,25 +688,27 @@ void do_tlb_overlap_fault(unsigned long cause, unsigned long address, 
 * Low Level ASM TLB handler calls this if it finds that HW and SW ASIDS

 * don't match

 */

void print_asid_mismatch(int is_fast_path)

void print_asid_mismatch(int mm_asid, int mmu_asid, int is_fast_path)

{

	int pid_sw, pid_hw;

	pid_sw = current->active_mm->context.asid;

	pid_hw = read_aux_reg(ARC_REG_PID) & 0xff;



	pr_emerg("ASID Mismatch in %s Path Handler: sw-pid=0x%x hw-pid=0x%x\n",

	       is_fast_path ? "Fast" : "Slow", pid_sw, pid_hw);

	       is_fast_path ? "Fast" : "Slow", mm_asid, mmu_asid);



	__asm__ __volatile__("flag 1");

}



void tlb_paranoid_check(unsigned int pid_sw, unsigned long addr)

void tlb_paranoid_check(unsigned int mm_asid, unsigned long addr)

{

	unsigned int pid_hw;

	unsigned int mmu_asid;



	pid_hw = read_aux_reg(ARC_REG_PID) & 0xff;

	mmu_asid = read_aux_reg(ARC_REG_PID) & 0xff;



	if (addr < 0x70000000 && ((pid_hw != pid_sw) || (pid_sw == NO_ASID)))

		print_asid_mismatch(0);

	/*

	 * At the time of a TLB miss/installation

	 *   - HW version needs to match SW version

	 *   - SW needs to have a valid ASID

	 */

	if (addr < 0x70000000 &&

	    ((mmu_asid != mm_asid) || (mm_asid == NO_ASID)))

		print_asid_mismatch(mm_asid, mmu_asid, 0);

}

#endif

arch/arc/mm/tlbex.S

+7 −9
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ ex_saved_reg1: 
	; VERIFY if the ASID in MMU-PID Reg is same as

	; one in Linux data structures



	DBG_ASID_MISMATCH

	tlb_paranoid_check_asm

.endm



.macro TLBMISS_RESTORE_REGS
@@ -133,31 +133,29 @@ ex_saved_reg1: 
; In bizzare scenrios SW and HW ASID can get out-of-sync which is trouble.

; So we try to detect this in TLB Mis shandler





.macro DBG_ASID_MISMATCH

.macro tlb_paranoid_check_asm



#ifdef CONFIG_ARC_DBG_TLB_PARANOIA



	; make sure h/w ASID is same as s/w ASID



	GET_CURR_TASK_ON_CPU  r3

	ld r0, [r3, TASK_ACT_MM]

	ld r0, [r0, MM_CTXT+MM_CTXT_ASID]



	lr r1, [ARC_REG_PID]

	and r1, r1, 0xFF



	breq r1, r0, 5f



	; Error if H/w and S/w ASID don't match, but NOT if in kernel mode

	lr  r0, [erstatus]

	bbit0 r0, STATUS_U_BIT, 5f

	lr  r2, [erstatus]

	bbit0 r2, STATUS_U_BIT, 5f



	; We sure are in troubled waters, Flag the error, but to do so

	; need to switch to kernel mode stack to call error routine

	GET_TSK_STACK_BASE   r3, sp



	; Call printk to shoutout aloud

	mov r0, 1

	mov r2, 1

	j print_asid_mismatch



5:	; ASIDs match so proceed normally