xref: /openbmc/linux/arch/arm/mm/abort-ev7.S (revision 588b48ca)
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	/*
17	 * The effect of data aborts on on the exclusive access monitor are
18	 * UNPREDICTABLE. Do a CLREX to clear the state
19	 */
20	clrex
21
22	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
23	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
24
25	/*
26	 * V6 code adjusts the returned DFSR.
27	 * New designs should not need to patch up faults.
28	 */
29
30#if defined(CONFIG_VERIFY_PERMISSION_FAULT)
31	/*
32	 * Detect erroneous permission failures and fix
33	 */
34	ldr	r3, =0x40d			@ On permission fault
35	and	r3, r1, r3
36	cmp	r3, #0x0d
37	bne	do_DataAbort
38
39	mcr	p15, 0, r0, c7, c8, 0   	@ Retranslate FAR
40	isb
41	mrc	p15, 0, ip, c7, c4, 0   	@ Read the PAR
42	and	r3, ip, #0x7b   		@ On translation fault
43	cmp	r3, #0x0b
44	bne	do_DataAbort
45	bic	r1, r1, #0xf			@ Fix up FSR FS[5:0]
46	and	ip, ip, #0x7e
47	orr	r1, r1, ip, LSR #1
48#endif
49
50	b	do_DataAbort
51ENDPROC(v7_early_abort)
52