linux/linux-5.4.31/arch/arm/mm/abort-ev5t.S

32 lines
983 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/linkage.h>
#include <asm/assembler.h>
#include "abort-macro.S"
/*
* Function: v5t_early_abort
*
* Params : r2 = pt_regs
* : r4 = aborted context pc
* : r5 = aborted context psr
*
* Returns : r4 - r11, r13 preserved
*
* Purpose : obtain information about current aborted instruction.
* Note: we read user space. This means we might cause a data
* abort here if the I-TLB and D-TLB aren't seeing the same
* picture. Unfortunately, this does happen. We live with it.
*/
.align 5
ENTRY(v5t_early_abort)
mrc p15, 0, r1, c5, c0, 0 @ get FSR
mrc p15, 0, r0, c6, c0, 0 @ get FAR
do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3
ldreq r3, [r4] @ read aborted ARM instruction
uaccess_disable ip @ disable user access
bic r1, r1, #1 << 11 @ clear bits 11 of FSR
teq_ldrd tmp=ip, insn=r3 @ insn was LDRD?
beq do_DataAbort @ yes
tst r3, #1 << 20 @ check write
orreq r1, r1, #1 << 11
b do_DataAbort