Initial import

1 files changed, 220 insertions, 0 deletions

diff --git a/arch/arm/mm/abort-lv4t.S b/arch/arm/mm/abort-lv4t.S
new file mode 100644
index 000000000..f3982580c
--- /dev/null
+++ b/arch/arm/mm/abort-lv4t.S
@@ -0,0 +1,220 @@
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+/*
+ * Function: v4t_late_abort
+ *
+ * Params  : r2 = pt_regs
+ *	   : r4 = aborted context pc
+ *	   : r5 = aborted context psr
+ *
+ * Returns : r4-r5, r10-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.
+ */
+ENTRY(v4t_late_abort)
+	tst	r5, #PSR_T_BIT			@ check for thumb mode
+#ifdef CONFIG_CPU_CP15_MMU
+	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
+	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
+	bic	r1, r1, #1 << 11 | 1 << 10	@ clear bits 11 and 10 of FSR
+#else
+	mov	r0, #0				@ clear r0, r1 (no FSR/FAR)
+	mov	r1, #0
+#endif
+	bne	.data_thumb_abort
+	ldr	r8, [r4]			@ read arm instruction
+	tst	r8, #1 << 20			@ L = 1 -> write?
+	orreq	r1, r1, #1 << 11		@ yes.
+	and	r7, r8, #15 << 24
+	add	pc, pc, r7, lsr #22		@ Now branch to the relevant processing routine
+	nop
+
+/* 0 */	b	.data_arm_lateldrhpost		@ ldrh	rd, [rn], #m/rm
+/* 1 */	b	.data_arm_lateldrhpre		@ ldrh	rd, [rn, #m/rm]
+/* 2 */	b	.data_unknown
+/* 3 */	b	.data_unknown
+/* 4 */	b	.data_arm_lateldrpostconst	@ ldr	rd, [rn], #m
+/* 5 */	b	.data_arm_lateldrpreconst	@ ldr	rd, [rn, #m] 
+/* 6 */	b	.data_arm_lateldrpostreg	@ ldr	rd, [rn], rm
+/* 7 */	b	.data_arm_lateldrprereg		@ ldr	rd, [rn, rm]
+/* 8 */	b	.data_arm_ldmstm		@ ldm*a	rn, <rlist>
+/* 9 */	b	.data_arm_ldmstm		@ ldm*b	rn, <rlist>
+/* a */	b	.data_unknown
+/* b */	b	.data_unknown
+/* c */	b	do_DataAbort			@ ldc	rd, [rn], #m	@ Same as ldr	rd, [rn], #m
+/* d */	b	do_DataAbort			@ ldc	rd, [rn, #m]
+/* e */	b	.data_unknown
+/* f */
+.data_unknown:	@ Part of jumptable
+	mov	r0, r4
+	mov	r1, r8
+	b	baddataabort
+
+.data_arm_ldmstm:
+	tst	r8, #1 << 21			@ check writeback bit
+	beq	do_DataAbort			@ no writeback -> no fixup
+	mov	r7, #0x11
+	orr	r7, r7, #0x1100
+	and	r6, r8, r7
+	and	r9, r8, r7, lsl #1
+	add	r6, r6, r9, lsr #1
+	and	r9, r8, r7, lsl #2
+	add	r6, r6, r9, lsr #2
+	and	r9, r8, r7, lsl #3
+	add	r6, r6, r9, lsr #3
+	add	r6, r6, r6, lsr #8
+	add	r6, r6, r6, lsr #4
+	and	r6, r6, #15			@ r6 = no. of registers to transfer.
+	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
+	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
+	tst	r8, #1 << 23			@ Check U bit
+	subne	r7, r7, r6, lsl #2		@ Undo increment
+	addeq	r7, r7, r6, lsl #2		@ Undo decrement
+	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
+	b	do_DataAbort
+
+.data_arm_lateldrhpre:
+	tst	r8, #1 << 21			@ Check writeback bit
+	beq	do_DataAbort			@ No writeback -> no fixup
+.data_arm_lateldrhpost:
+	and	r9, r8, #0x00f			@ get Rm / low nibble of immediate value
+	tst	r8, #1 << 22			@ if (immediate offset)
+	andne	r6, r8, #0xf00			@ { immediate high nibble
+	orrne	r6, r9, r6, lsr #4		@   combine nibbles } else
+	ldreq	r6, [r2, r9, lsl #2]		@ { load Rm value }
+.data_arm_apply_r6_and_rn:
+	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
+	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
+	tst	r8, #1 << 23			@ Check U bit
+	subne	r7, r7, r6			@ Undo incrmenet
+	addeq	r7, r7, r6			@ Undo decrement
+	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
+	b	do_DataAbort
+
+.data_arm_lateldrpreconst:
+	tst	r8, #1 << 21			@ check writeback bit
+	beq	do_DataAbort			@ no writeback -> no fixup
+.data_arm_lateldrpostconst:
+	movs	r6, r8, lsl #20			@ Get offset
+	beq	do_DataAbort			@ zero -> no fixup
+	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
+	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
+	tst	r8, #1 << 23			@ Check U bit
+	subne	r7, r7, r6, lsr #20		@ Undo increment
+	addeq	r7, r7, r6, lsr #20		@ Undo decrement
+	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
+	b	do_DataAbort
+
+.data_arm_lateldrprereg:
+	tst	r8, #1 << 21			@ check writeback bit
+	beq	do_DataAbort			@ no writeback -> no fixup
+.data_arm_lateldrpostreg:
+	and	r7, r8, #15			@ Extract 'm' from instruction
+	ldr	r6, [r2, r7, lsl #2]		@ Get register 'Rm'
+	mov	r9, r8, lsr #7			@ get shift count
+	ands	r9, r9, #31
+	and	r7, r8, #0x70			@ get shift type
+	orreq	r7, r7, #8			@ shift count = 0
+	add	pc, pc, r7
+	nop
+
+	mov	r6, r6, lsl r9			@ 0: LSL #!0
+	b	.data_arm_apply_r6_and_rn
+	b	.data_arm_apply_r6_and_rn	@ 1: LSL #0
+	nop
+	b	.data_unknown			@ 2: MUL?
+	nop
+	b	.data_unknown			@ 3: MUL?
+	nop
+	mov	r6, r6, lsr r9			@ 4: LSR #!0
+	b	.data_arm_apply_r6_and_rn
+	mov	r6, r6, lsr #32			@ 5: LSR #32
+	b	.data_arm_apply_r6_and_rn
+	b	.data_unknown			@ 6: MUL?
+	nop
+	b	.data_unknown			@ 7: MUL?
+	nop
+	mov	r6, r6, asr r9			@ 8: ASR #!0
+	b	.data_arm_apply_r6_and_rn
+	mov	r6, r6, asr #32			@ 9: ASR #32
+	b	.data_arm_apply_r6_and_rn
+	b	.data_unknown			@ A: MUL?
+	nop
+	b	.data_unknown			@ B: MUL?
+	nop
+	mov	r6, r6, ror r9			@ C: ROR #!0
+	b	.data_arm_apply_r6_and_rn
+	mov	r6, r6, rrx			@ D: RRX
+	b	.data_arm_apply_r6_and_rn
+	b	.data_unknown			@ E: MUL?
+	nop
+	b	.data_unknown			@ F: MUL?
+
+.data_thumb_abort:
+	ldrh	r8, [r4]			@ read instruction
+	tst	r8, #1 << 11			@ L = 1 -> write?
+	orreq	r1, r1, #1 << 8			@ yes
+	and	r7, r8, #15 << 12
+	add	pc, pc, r7, lsr #10		@ lookup in table
+	nop
+
+/* 0 */	b	.data_unknown
+/* 1 */	b	.data_unknown
+/* 2 */	b	.data_unknown
+/* 3 */	b	.data_unknown
+/* 4 */	b	.data_unknown
+/* 5 */	b	.data_thumb_reg
+/* 6 */	b	do_DataAbort
+/* 7 */	b	do_DataAbort
+/* 8 */	b	do_DataAbort
+/* 9 */	b	do_DataAbort
+/* A */	b	.data_unknown
+/* B */	b	.data_thumb_pushpop
+/* C */	b	.data_thumb_ldmstm
+/* D */	b	.data_unknown
+/* E */	b	.data_unknown
+/* F */	b	.data_unknown
+
+.data_thumb_reg:
+	tst	r8, #1 << 9
+	beq	do_DataAbort
+	tst	r8, #1 << 10			@ If 'S' (signed) bit is set
+	movne	r1, #0				@ it must be a load instr
+	b	do_DataAbort
+
+.data_thumb_pushpop:
+	tst	r8, #1 << 10
+	beq	.data_unknown
+	and	r6, r8, #0x55			@ hweight8(r8) + R bit
+	and	r9, r8, #0xaa
+	add	r6, r6, r9, lsr #1
+	and	r9, r6, #0xcc
+	and	r6, r6, #0x33
+	add	r6, r6, r9, lsr #2
+	movs	r7, r8, lsr #9			@ C = r8 bit 8 (R bit)
+	adc	r6, r6, r6, lsr #4		@ high + low nibble + R bit
+	and	r6, r6, #15			@ number of regs to transfer
+	ldr	r7, [r2, #13 << 2]
+	tst	r8, #1 << 11
+	addeq	r7, r7, r6, lsl #2		@ increment SP if PUSH
+	subne	r7, r7, r6, lsl #2		@ decrement SP if POP
+	str	r7, [r2, #13 << 2]
+	b	do_DataAbort
+
+.data_thumb_ldmstm:
+	and	r6, r8, #0x55			@ hweight8(r8)
+	and	r9, r8, #0xaa
+	add	r6, r6, r9, lsr #1
+	and	r9, r6, #0xcc
+	and	r6, r6, #0x33
+	add	r6, r6, r9, lsr #2
+	add	r6, r6, r6, lsr #4
+	and	r9, r8, #7 << 8
+	ldr	r7, [r2, r9, lsr #6]
+	and	r6, r6, #15			@ number of regs to transfer
+	sub	r7, r7, r6, lsl #2		@ always decrement
+	str	r7, [r2, r9, lsr #6]
+	b	do_DataAbort