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v3.15
  1#include <linux/linkage.h>
  2#include <asm/assembler.h>
  3/*
  4 * Function: v4t_late_abort
  5 *
  6 * Params  : r2 = pt_regs
  7 *	   : r4 = aborted context pc
  8 *	   : r5 = aborted context psr
  9 *
 10 * Returns : r4-r5, r10-r11, r13 preserved
 11 *
 12 * Purpose : obtain information about current aborted instruction.
 13 * Note: we read user space.  This means we might cause a data
 14 * abort here if the I-TLB and D-TLB aren't seeing the same
 15 * picture.  Unfortunately, this does happen.  We live with it.
 16 */
 17ENTRY(v4t_late_abort)
 18	tst	r5, #PSR_T_BIT			@ check for thumb mode
 19#ifdef CONFIG_CPU_CP15_MMU
 20	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
 21	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
 22	bic	r1, r1, #1 << 11 | 1 << 10	@ clear bits 11 and 10 of FSR
 23#else
 24	mov	r0, #0				@ clear r0, r1 (no FSR/FAR)
 25	mov	r1, #0
 26#endif
 27	bne	.data_thumb_abort
 28	ldr	r8, [r4]			@ read arm instruction
 29	tst	r8, #1 << 20			@ L = 1 -> write?
 30	orreq	r1, r1, #1 << 11		@ yes.
 31	and	r7, r8, #15 << 24
 32	add	pc, pc, r7, lsr #22		@ Now branch to the relevant processing routine
 33	nop
 34
 35/* 0 */	b	.data_arm_lateldrhpost		@ ldrh	rd, [rn], #m/rm
 36/* 1 */	b	.data_arm_lateldrhpre		@ ldrh	rd, [rn, #m/rm]
 37/* 2 */	b	.data_unknown
 38/* 3 */	b	.data_unknown
 39/* 4 */	b	.data_arm_lateldrpostconst	@ ldr	rd, [rn], #m
 40/* 5 */	b	.data_arm_lateldrpreconst	@ ldr	rd, [rn, #m] 
 41/* 6 */	b	.data_arm_lateldrpostreg	@ ldr	rd, [rn], rm
 42/* 7 */	b	.data_arm_lateldrprereg		@ ldr	rd, [rn, rm]
 43/* 8 */	b	.data_arm_ldmstm		@ ldm*a	rn, <rlist>
 44/* 9 */	b	.data_arm_ldmstm		@ ldm*b	rn, <rlist>
 45/* a */	b	.data_unknown
 46/* b */	b	.data_unknown
 47/* c */	b	do_DataAbort			@ ldc	rd, [rn], #m	@ Same as ldr	rd, [rn], #m
 48/* d */	b	do_DataAbort			@ ldc	rd, [rn, #m]
 49/* e */	b	.data_unknown
 50/* f */
 51.data_unknown:	@ Part of jumptable
 52	mov	r0, r4
 53	mov	r1, r8
 54	b	baddataabort
 55
 56.data_arm_ldmstm:
 57	tst	r8, #1 << 21			@ check writeback bit
 58	beq	do_DataAbort			@ no writeback -> no fixup
 59	mov	r7, #0x11
 60	orr	r7, r7, #0x1100
 61	and	r6, r8, r7
 62	and	r9, r8, r7, lsl #1
 63	add	r6, r6, r9, lsr #1
 64	and	r9, r8, r7, lsl #2
 65	add	r6, r6, r9, lsr #2
 66	and	r9, r8, r7, lsl #3
 67	add	r6, r6, r9, lsr #3
 68	add	r6, r6, r6, lsr #8
 69	add	r6, r6, r6, lsr #4
 70	and	r6, r6, #15			@ r6 = no. of registers to transfer.
 71	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
 72	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
 73	tst	r8, #1 << 23			@ Check U bit
 74	subne	r7, r7, r6, lsl #2		@ Undo increment
 75	addeq	r7, r7, r6, lsl #2		@ Undo decrement
 76	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
 77	b	do_DataAbort
 78
 79.data_arm_lateldrhpre:
 80	tst	r8, #1 << 21			@ Check writeback bit
 81	beq	do_DataAbort			@ No writeback -> no fixup
 82.data_arm_lateldrhpost:
 83	and	r9, r8, #0x00f			@ get Rm / low nibble of immediate value
 84	tst	r8, #1 << 22			@ if (immediate offset)
 85	andne	r6, r8, #0xf00			@ { immediate high nibble
 86	orrne	r6, r9, r6, lsr #4		@   combine nibbles } else
 87	ldreq	r6, [r2, r9, lsl #2]		@ { load Rm value }
 88.data_arm_apply_r6_and_rn:
 89	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
 90	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
 91	tst	r8, #1 << 23			@ Check U bit
 92	subne	r7, r7, r6			@ Undo incrmenet
 93	addeq	r7, r7, r6			@ Undo decrement
 94	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
 95	b	do_DataAbort
 96
 97.data_arm_lateldrpreconst:
 98	tst	r8, #1 << 21			@ check writeback bit
 99	beq	do_DataAbort			@ no writeback -> no fixup
100.data_arm_lateldrpostconst:
101	movs	r6, r8, lsl #20			@ Get offset
102	beq	do_DataAbort			@ zero -> no fixup
103	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
104	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
105	tst	r8, #1 << 23			@ Check U bit
106	subne	r7, r7, r6, lsr #20		@ Undo increment
107	addeq	r7, r7, r6, lsr #20		@ Undo decrement
108	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
109	b	do_DataAbort
110
111.data_arm_lateldrprereg:
112	tst	r8, #1 << 21			@ check writeback bit
113	beq	do_DataAbort			@ no writeback -> no fixup
114.data_arm_lateldrpostreg:
115	and	r7, r8, #15			@ Extract 'm' from instruction
116	ldr	r6, [r2, r7, lsl #2]		@ Get register 'Rm'
117	mov	r9, r8, lsr #7			@ get shift count
118	ands	r9, r9, #31
119	and	r7, r8, #0x70			@ get shift type
120	orreq	r7, r7, #8			@ shift count = 0
121	add	pc, pc, r7
122	nop
123
124	mov	r6, r6, lsl r9			@ 0: LSL #!0
125	b	.data_arm_apply_r6_and_rn
126	b	.data_arm_apply_r6_and_rn	@ 1: LSL #0
127	nop
128	b	.data_unknown			@ 2: MUL?
129	nop
130	b	.data_unknown			@ 3: MUL?
131	nop
132	mov	r6, r6, lsr r9			@ 4: LSR #!0
133	b	.data_arm_apply_r6_and_rn
134	mov	r6, r6, lsr #32			@ 5: LSR #32
135	b	.data_arm_apply_r6_and_rn
136	b	.data_unknown			@ 6: MUL?
137	nop
138	b	.data_unknown			@ 7: MUL?
139	nop
140	mov	r6, r6, asr r9			@ 8: ASR #!0
141	b	.data_arm_apply_r6_and_rn
142	mov	r6, r6, asr #32			@ 9: ASR #32
143	b	.data_arm_apply_r6_and_rn
144	b	.data_unknown			@ A: MUL?
145	nop
146	b	.data_unknown			@ B: MUL?
147	nop
148	mov	r6, r6, ror r9			@ C: ROR #!0
149	b	.data_arm_apply_r6_and_rn
150	mov	r6, r6, rrx			@ D: RRX
151	b	.data_arm_apply_r6_and_rn
152	b	.data_unknown			@ E: MUL?
153	nop
154	b	.data_unknown			@ F: MUL?
155
156.data_thumb_abort:
157	ldrh	r8, [r4]			@ read instruction
158	tst	r8, #1 << 11			@ L = 1 -> write?
159	orreq	r1, r1, #1 << 8			@ yes
160	and	r7, r8, #15 << 12
161	add	pc, pc, r7, lsr #10		@ lookup in table
162	nop
163
164/* 0 */	b	.data_unknown
165/* 1 */	b	.data_unknown
166/* 2 */	b	.data_unknown
167/* 3 */	b	.data_unknown
168/* 4 */	b	.data_unknown
169/* 5 */	b	.data_thumb_reg
170/* 6 */	b	do_DataAbort
171/* 7 */	b	do_DataAbort
172/* 8 */	b	do_DataAbort
173/* 9 */	b	do_DataAbort
174/* A */	b	.data_unknown
175/* B */	b	.data_thumb_pushpop
176/* C */	b	.data_thumb_ldmstm
177/* D */	b	.data_unknown
178/* E */	b	.data_unknown
179/* F */	b	.data_unknown
180
181.data_thumb_reg:
182	tst	r8, #1 << 9
183	beq	do_DataAbort
184	tst	r8, #1 << 10			@ If 'S' (signed) bit is set
185	movne	r1, #0				@ it must be a load instr
186	b	do_DataAbort
187
188.data_thumb_pushpop:
189	tst	r8, #1 << 10
190	beq	.data_unknown
191	and	r6, r8, #0x55			@ hweight8(r8) + R bit
192	and	r9, r8, #0xaa
193	add	r6, r6, r9, lsr #1
194	and	r9, r6, #0xcc
195	and	r6, r6, #0x33
196	add	r6, r6, r9, lsr #2
197	movs	r7, r8, lsr #9			@ C = r8 bit 8 (R bit)
198	adc	r6, r6, r6, lsr #4		@ high + low nibble + R bit
199	and	r6, r6, #15			@ number of regs to transfer
200	ldr	r7, [r2, #13 << 2]
201	tst	r8, #1 << 11
202	addeq	r7, r7, r6, lsl #2		@ increment SP if PUSH
203	subne	r7, r7, r6, lsl #2		@ decrement SP if POP
204	str	r7, [r2, #13 << 2]
205	b	do_DataAbort
206
207.data_thumb_ldmstm:
208	and	r6, r8, #0x55			@ hweight8(r8)
209	and	r9, r8, #0xaa
210	add	r6, r6, r9, lsr #1
211	and	r9, r6, #0xcc
212	and	r6, r6, #0x33
213	add	r6, r6, r9, lsr #2
214	add	r6, r6, r6, lsr #4
215	and	r9, r8, #7 << 8
216	ldr	r7, [r2, r9, lsr #6]
217	and	r6, r6, #15			@ number of regs to transfer
218	sub	r7, r7, r6, lsl #2		@ always decrement
219	str	r7, [r2, r9, lsr #6]
220	b	do_DataAbort
v3.1
  1#include <linux/linkage.h>
  2#include <asm/assembler.h>
  3/*
  4 * Function: v4t_late_abort
  5 *
  6 * Params  : r2 = pt_regs
  7 *	   : r4 = aborted context pc
  8 *	   : r5 = aborted context psr
  9 *
 10 * Returns : r4-r5, r10-r11, r13 preserved
 11 *
 12 * Purpose : obtain information about current aborted instruction.
 13 * Note: we read user space.  This means we might cause a data
 14 * abort here if the I-TLB and D-TLB aren't seeing the same
 15 * picture.  Unfortunately, this does happen.  We live with it.
 16 */
 17ENTRY(v4t_late_abort)
 18	tst	r5, #PSR_T_BIT			@ check for thumb mode
 19#ifdef CONFIG_CPU_CP15_MMU
 20	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
 21	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
 22	bic	r1, r1, #1 << 11 | 1 << 10	@ clear bits 11 and 10 of FSR
 23#else
 24	mov	r0, #0				@ clear r0, r1 (no FSR/FAR)
 25	mov	r1, #0
 26#endif
 27	bne	.data_thumb_abort
 28	ldr	r8, [r4]			@ read arm instruction
 29	tst	r8, #1 << 20			@ L = 1 -> write?
 30	orreq	r1, r1, #1 << 11		@ yes.
 31	and	r7, r8, #15 << 24
 32	add	pc, pc, r7, lsr #22		@ Now branch to the relevant processing routine
 33	nop
 34
 35/* 0 */	b	.data_arm_lateldrhpost		@ ldrh	rd, [rn], #m/rm
 36/* 1 */	b	.data_arm_lateldrhpre		@ ldrh	rd, [rn, #m/rm]
 37/* 2 */	b	.data_unknown
 38/* 3 */	b	.data_unknown
 39/* 4 */	b	.data_arm_lateldrpostconst	@ ldr	rd, [rn], #m
 40/* 5 */	b	.data_arm_lateldrpreconst	@ ldr	rd, [rn, #m] 
 41/* 6 */	b	.data_arm_lateldrpostreg	@ ldr	rd, [rn], rm
 42/* 7 */	b	.data_arm_lateldrprereg		@ ldr	rd, [rn, rm]
 43/* 8 */	b	.data_arm_ldmstm		@ ldm*a	rn, <rlist>
 44/* 9 */	b	.data_arm_ldmstm		@ ldm*b	rn, <rlist>
 45/* a */	b	.data_unknown
 46/* b */	b	.data_unknown
 47/* c */	b	do_DataAbort			@ ldc	rd, [rn], #m	@ Same as ldr	rd, [rn], #m
 48/* d */	b	do_DataAbort			@ ldc	rd, [rn, #m]
 49/* e */	b	.data_unknown
 50/* f */
 51.data_unknown:	@ Part of jumptable
 52	mov	r0, r4
 53	mov	r1, r8
 54	b	baddataabort
 55
 56.data_arm_ldmstm:
 57	tst	r8, #1 << 21			@ check writeback bit
 58	beq	do_DataAbort			@ no writeback -> no fixup
 59	mov	r7, #0x11
 60	orr	r7, r7, #0x1100
 61	and	r6, r8, r7
 62	and	r9, r8, r7, lsl #1
 63	add	r6, r6, r9, lsr #1
 64	and	r9, r8, r7, lsl #2
 65	add	r6, r6, r9, lsr #2
 66	and	r9, r8, r7, lsl #3
 67	add	r6, r6, r9, lsr #3
 68	add	r6, r6, r6, lsr #8
 69	add	r6, r6, r6, lsr #4
 70	and	r6, r6, #15			@ r6 = no. of registers to transfer.
 71	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
 72	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
 73	tst	r8, #1 << 23			@ Check U bit
 74	subne	r7, r7, r6, lsl #2		@ Undo increment
 75	addeq	r7, r7, r6, lsl #2		@ Undo decrement
 76	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
 77	b	do_DataAbort
 78
 79.data_arm_lateldrhpre:
 80	tst	r8, #1 << 21			@ Check writeback bit
 81	beq	do_DataAbort			@ No writeback -> no fixup
 82.data_arm_lateldrhpost:
 83	and	r9, r8, #0x00f			@ get Rm / low nibble of immediate value
 84	tst	r8, #1 << 22			@ if (immediate offset)
 85	andne	r6, r8, #0xf00			@ { immediate high nibble
 86	orrne	r6, r9, r6, lsr #4		@   combine nibbles } else
 87	ldreq	r6, [r2, r9, lsl #2]		@ { load Rm value }
 88.data_arm_apply_r6_and_rn:
 89	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
 90	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
 91	tst	r8, #1 << 23			@ Check U bit
 92	subne	r7, r7, r6			@ Undo incrmenet
 93	addeq	r7, r7, r6			@ Undo decrement
 94	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
 95	b	do_DataAbort
 96
 97.data_arm_lateldrpreconst:
 98	tst	r8, #1 << 21			@ check writeback bit
 99	beq	do_DataAbort			@ no writeback -> no fixup
100.data_arm_lateldrpostconst:
101	movs	r6, r8, lsl #20			@ Get offset
102	beq	do_DataAbort			@ zero -> no fixup
103	and	r9, r8, #15 << 16		@ Extract 'n' from instruction
104	ldr	r7, [r2, r9, lsr #14]		@ Get register 'Rn'
105	tst	r8, #1 << 23			@ Check U bit
106	subne	r7, r7, r6, lsr #20		@ Undo increment
107	addeq	r7, r7, r6, lsr #20		@ Undo decrement
108	str	r7, [r2, r9, lsr #14]		@ Put register 'Rn'
109	b	do_DataAbort
110
111.data_arm_lateldrprereg:
112	tst	r8, #1 << 21			@ check writeback bit
113	beq	do_DataAbort			@ no writeback -> no fixup
114.data_arm_lateldrpostreg:
115	and	r7, r8, #15			@ Extract 'm' from instruction
116	ldr	r6, [r2, r7, lsl #2]		@ Get register 'Rm'
117	mov	r9, r8, lsr #7			@ get shift count
118	ands	r9, r9, #31
119	and	r7, r8, #0x70			@ get shift type
120	orreq	r7, r7, #8			@ shift count = 0
121	add	pc, pc, r7
122	nop
123
124	mov	r6, r6, lsl r9			@ 0: LSL #!0
125	b	.data_arm_apply_r6_and_rn
126	b	.data_arm_apply_r6_and_rn	@ 1: LSL #0
127	nop
128	b	.data_unknown			@ 2: MUL?
129	nop
130	b	.data_unknown			@ 3: MUL?
131	nop
132	mov	r6, r6, lsr r9			@ 4: LSR #!0
133	b	.data_arm_apply_r6_and_rn
134	mov	r6, r6, lsr #32			@ 5: LSR #32
135	b	.data_arm_apply_r6_and_rn
136	b	.data_unknown			@ 6: MUL?
137	nop
138	b	.data_unknown			@ 7: MUL?
139	nop
140	mov	r6, r6, asr r9			@ 8: ASR #!0
141	b	.data_arm_apply_r6_and_rn
142	mov	r6, r6, asr #32			@ 9: ASR #32
143	b	.data_arm_apply_r6_and_rn
144	b	.data_unknown			@ A: MUL?
145	nop
146	b	.data_unknown			@ B: MUL?
147	nop
148	mov	r6, r6, ror r9			@ C: ROR #!0
149	b	.data_arm_apply_r6_and_rn
150	mov	r6, r6, rrx			@ D: RRX
151	b	.data_arm_apply_r6_and_rn
152	b	.data_unknown			@ E: MUL?
153	nop
154	b	.data_unknown			@ F: MUL?
155
156.data_thumb_abort:
157	ldrh	r8, [r4]			@ read instruction
158	tst	r8, #1 << 11			@ L = 1 -> write?
159	orreq	r1, r1, #1 << 8			@ yes
160	and	r7, r8, #15 << 12
161	add	pc, pc, r7, lsr #10		@ lookup in table
162	nop
163
164/* 0 */	b	.data_unknown
165/* 1 */	b	.data_unknown
166/* 2 */	b	.data_unknown
167/* 3 */	b	.data_unknown
168/* 4 */	b	.data_unknown
169/* 5 */	b	.data_thumb_reg
170/* 6 */	b	do_DataAbort
171/* 7 */	b	do_DataAbort
172/* 8 */	b	do_DataAbort
173/* 9 */	b	do_DataAbort
174/* A */	b	.data_unknown
175/* B */	b	.data_thumb_pushpop
176/* C */	b	.data_thumb_ldmstm
177/* D */	b	.data_unknown
178/* E */	b	.data_unknown
179/* F */	b	.data_unknown
180
181.data_thumb_reg:
182	tst	r8, #1 << 9
183	beq	do_DataAbort
184	tst	r8, #1 << 10			@ If 'S' (signed) bit is set
185	movne	r1, #0				@ it must be a load instr
186	b	do_DataAbort
187
188.data_thumb_pushpop:
189	tst	r8, #1 << 10
190	beq	.data_unknown
191	and	r6, r8, #0x55			@ hweight8(r8) + R bit
192	and	r9, r8, #0xaa
193	add	r6, r6, r9, lsr #1
194	and	r9, r6, #0xcc
195	and	r6, r6, #0x33
196	add	r6, r6, r9, lsr #2
197	movs	r7, r8, lsr #9			@ C = r8 bit 8 (R bit)
198	adc	r6, r6, r6, lsr #4		@ high + low nibble + R bit
199	and	r6, r6, #15			@ number of regs to transfer
200	ldr	r7, [r2, #13 << 2]
201	tst	r8, #1 << 11
202	addeq	r7, r7, r6, lsl #2		@ increment SP if PUSH
203	subne	r7, r7, r6, lsl #2		@ decrement SP if POP
204	str	r7, [r2, #13 << 2]
205	b	do_DataAbort
206
207.data_thumb_ldmstm:
208	and	r6, r8, #0x55			@ hweight8(r8)
209	and	r9, r8, #0xaa
210	add	r6, r6, r9, lsr #1
211	and	r9, r6, #0xcc
212	and	r6, r6, #0x33
213	add	r6, r6, r9, lsr #2
214	add	r6, r6, r6, lsr #4
215	and	r9, r8, #7 << 8
216	ldr	r7, [r2, r9, lsr #6]
217	and	r6, r6, #15			@ number of regs to transfer
218	sub	r7, r7, r6, lsl #2		@ always decrement
219	str	r7, [r2, r9, lsr #6]
220	b	do_DataAbort