xref: /linux/arch/arm/mm/abort-ev7.S (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1#include <linux/linkage.h>
2#include <asm/assembler.h>
3/*
4 * Function: v7_early_abort
5 *
6 * Params  : r2 = pt_regs
7 *	   : r4 = aborted context pc
8 *	   : r5 = aborted context psr
9 *
10 * Returns : r4 - r11, r13 preserved
11 *
12 * Purpose : obtain information about current aborted instruction.
13 */
14	.align	5
15ENTRY(v7_early_abort)
16	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
17	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
18	uaccess_disable ip			@ disable userspace access
19
20	/*
21	 * V6 code adjusts the returned DFSR.
22	 * New designs should not need to patch up faults.
23	 */
24
25#if defined(CONFIG_VERIFY_PERMISSION_FAULT)
26	/*
27	 * Detect erroneous permission failures and fix
28	 */
29	ldr	r3, =0x40d			@ On permission fault
30	and	r3, r1, r3
31	cmp	r3, #0x0d
32	bne	do_DataAbort
33
34	mcr	p15, 0, r0, c7, c8, 0   	@ Retranslate FAR
35	isb
36	mrc	p15, 0, ip, c7, c4, 0   	@ Read the PAR
37	and	r3, ip, #0x7b   		@ On translation fault
38	cmp	r3, #0x0b
39	bne	do_DataAbort
40	bic	r1, r1, #0xf			@ Fix up FSR FS[5:0]
41	and	ip, ip, #0x7e
42	orr	r1, r1, ip, LSR #1
43#endif
44
45	b	do_DataAbort
46ENDPROC(v7_early_abort)
47