Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 42 insertions, 0 deletions

diff --git a/arch/arm/mm/abort-macro.S b/arch/arm/mm/abort-macro.S
new file mode 100644
index 000000000000..d7cb1bfa51a4
--- /dev/null
+++ b/arch/arm/mm/abort-macro.S
@@ -0,0 +1,42 @@
+/*
+ * 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
+	tst	r3, #PSR_T_BIT
+	beq	not_thumb
+	ldrh	r3, [r2]			@ Read aborted Thumb instruction
+	and	r3, r3, # 0xfe00		@ Mask opcode field
+	cmp	r3, # 0x5600			@ Is it ldrsb?
+	orreq	r3, r3, #1 << 11		@ Set L-bit if yes
+	tst	r3, #1 << 11			@ L = 0 -> write
+	orreq	r1, r1, #1 << 11		@ yes.
+	mov	pc, lr
+not_thumb:
+	.endm
+
+/*
+ * We check for the following insturction encoding for LDRD.
+ *
+ * [27:25] == 0
+ *   [7:4] == 1101
+ *    [20] == 0
+ */
+ 	.macro	do_ldrd_abort
+ 	tst	r3, #0x0e000000			@ [27:25] == 0
+	bne	not_ldrd
+	and	r2, r3, #0x000000f0		@ [7:4] == 1101
+	cmp	r2, #0x000000d0
+	bne	not_ldrd
+	tst	r3, #1 << 20			@ [20] == 0
+	moveq	pc, lr
+not_ldrd:
+	.endm
+