xref: /linux/arch/arm/mm/abort-ev7.S (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1/* SPDX-License-Identifier: GPL-2.0 */
2#include <linux/linkage.h>
3#include <asm/assembler.h>
4/*
5 * Function: v7_early_abort
6 *
7 * Params  : r2 = pt_regs
8 *	   : r4 = aborted context pc
9 *	   : r5 = aborted context psr
10 *
11 * Returns : r4 - r11, r13 preserved
12 *
13 * Purpose : obtain information about current aborted instruction.
14 */
15	.align	5
16ENTRY(v7_early_abort)
17	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
18	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
19	uaccess_disable ip			@ disable userspace access
20
21	/*
22	 * V6 code adjusts the returned DFSR.
23	 * New designs should not need to patch up faults.
24	 */
25
26#if defined(CONFIG_VERIFY_PERMISSION_FAULT)
27	/*
28	 * Detect erroneous permission failures and fix
29	 */
30	ldr	r3, =0x40d			@ On permission fault
31	and	r3, r1, r3
32	cmp	r3, #0x0d
33	bne	do_DataAbort
34
35	mcr	p15, 0, r0, c7, c8, 0   	@ Retranslate FAR
36	isb
37	mrc	p15, 0, ip, c7, c4, 0   	@ Read the PAR
38	and	r3, ip, #0x7b   		@ On translation fault
39	cmp	r3, #0x0b
40	bne	do_DataAbort
41	bic	r1, r1, #0xf			@ Fix up FSR FS[5:0]
42	and	ip, ip, #0x7e
43	orr	r1, r1, ip, LSR #1
44#endif
45
46	b	do_DataAbort
47ENDPROC(v7_early_abort)
48