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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/arm/mm/abort-macro.S
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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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
+ 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 do_ldrd_abort, tmp, insn
+ tst \insn, #0x0e100000 @ [27:25,20] == 0
+ bne not_ldrd
+ and \tmp, \insn, #0x000000f0 @ [7:4] == 1101
+ cmp \tmp, #0x000000d0
+ beq do_DataAbort
+not_ldrd:
+ .endm
+