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- /*
- * The ARM LDRD and Thumb LDRSB instructions use bit 20/11 (ARM/Thumb)
- * differently than every other instruction, so it is set to 0 (write)
- * even though the instructions are read instructions. This means that
- * during an abort the instructions will be treated as a write and the
- * handler will raise a signal from unwriteable locations if they
- * fault. We have to specifically check for these instructions
- * from the abort handlers to treat them properly.
- *
- */
- .macro do_thumb_abort, fsr, pc, psr, tmp
- tst \psr, #PSR_T_BIT
- beq not_thumb
- ldrh \tmp, [\pc] @ Read aborted Thumb instruction
- uaccess_disable ip @ disable userspace access
- and \tmp, \tmp, # 0xfe00 @ Mask opcode field
- cmp \tmp, # 0x5600 @ Is it ldrsb?
- orreq \tmp, \tmp, #1 << 11 @ Set L-bit if yes
- tst \tmp, #1 << 11 @ L = 0 -> write
- orreq \fsr, \fsr, #1 << 11 @ yes.
- b do_DataAbort
- not_thumb:
- .endm
- /*
- * We check for the following instruction encoding for LDRD.
- *
- * [27:25] == 000
- * [7:4] == 1101
- * [20] == 0
- */
- .macro teq_ldrd, tmp, insn
- mov \tmp, #0x0e100000
- orr \tmp, #0x000000f0
- and \tmp, \insn, \tmp
- teq \tmp, #0x000000d0
- .endm
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