linux-stable-rt/arch/arm/mm/abort-ev6.S

44 lines
1.3 KiB
ArmAsm

#include <linux/linkage.h>
#include <asm/assembler.h>
#include "abort-macro.S"
/*
* Function: v6_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(v6_early_abort)
#ifdef CONFIG_CPU_V6
sub r1, sp, #4 @ Get unused stack location
strex r0, r1, [r1] @ Clear the exclusive monitor
#elif defined(CONFIG_CPU_32v6K)
clrex
#endif
mrc p15, 0, r1, c5, c0, 0 @ get FSR
mrc p15, 0, r0, c6, c0, 0 @ get FAR
/*
* Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR (erratum 326103).
* The test below covers all the write situations, including Java bytecodes
*/
bic r1, r1, #1 << 11 @ clear bit 11 of FSR
tst r5, #PSR_J_BIT @ Java?
bne do_DataAbort
do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3
ldreq r3, [r4] @ read aborted ARM instruction
#ifdef CONFIG_CPU_ENDIAN_BE8
reveq r3, r3
#endif
do_ldrd_abort tmp=ip, insn=r3
tst r3, #1 << 20 @ L = 0 -> write
orreq r1, r1, #1 << 11 @ yes.
b do_DataAbort