xref: /openbmc/linux/arch/sparc/kernel/spiterrs.S (revision d7a3d85e)
1	/* We need to carefully read the error status, ACK the errors,
2	 * prevent recursive traps, and pass the information on to C
3	 * code for logging.
4	 *
5	 * We pass the AFAR in as-is, and we encode the status
6	 * information as described in asm-sparc64/sfafsr.h
7	 */
8	.type		__spitfire_access_error,#function
9__spitfire_access_error:
10	/* Disable ESTATE error reporting so that we do not take
11	 * recursive traps and RED state the processor.
12	 */
13	stxa		%g0, [%g0] ASI_ESTATE_ERROR_EN
14	membar		#Sync
15
16	mov		UDBE_UE, %g1
17	ldxa		[%g0] ASI_AFSR, %g4	! Get AFSR
18
19	/* __spitfire_cee_trap branches here with AFSR in %g4 and
20	 * UDBE_CE in %g1.  It only clears ESTATE_ERR_CE in the ESTATE
21	 * Error Enable register.
22	 */
23__spitfire_cee_trap_continue:
24	ldxa		[%g0] ASI_AFAR, %g5	! Get AFAR
25
26	rdpr		%tt, %g3
27	and		%g3, 0x1ff, %g3		! Paranoia
28	sllx		%g3, SFSTAT_TRAP_TYPE_SHIFT, %g3
29	or		%g4, %g3, %g4
30	rdpr		%tl, %g3
31	cmp		%g3, 1
32	mov		1, %g3
33	bleu		%xcc, 1f
34	 sllx		%g3, SFSTAT_TL_GT_ONE_SHIFT, %g3
35
36	or		%g4, %g3, %g4
37
38	/* Read in the UDB error register state, clearing the sticky
39	 * error bits as-needed.  We only clear them if the UE bit is
40	 * set.  Likewise, __spitfire_cee_trap below will only do so
41	 * if the CE bit is set.
42	 *
43	 * NOTE: UltraSparc-I/II have high and low UDB error
44	 *       registers, corresponding to the two UDB units
45	 *       present on those chips.  UltraSparc-IIi only
46	 *       has a single UDB, called "SDB" in the manual.
47	 *       For IIi the upper UDB register always reads
48	 *       as zero so for our purposes things will just
49	 *       work with the checks below.
50	 */
511:	ldxa		[%g0] ASI_UDBH_ERROR_R, %g3
52	and		%g3, 0x3ff, %g7		! Paranoia
53	sllx		%g7, SFSTAT_UDBH_SHIFT, %g7
54	or		%g4, %g7, %g4
55	andcc		%g3, %g1, %g3		! UDBE_UE or UDBE_CE
56	be,pn		%xcc, 1f
57	 nop
58	stxa		%g3, [%g0] ASI_UDB_ERROR_W
59	membar		#Sync
60
611:	mov		0x18, %g3
62	ldxa		[%g3] ASI_UDBL_ERROR_R, %g3
63	and		%g3, 0x3ff, %g7		! Paranoia
64	sllx		%g7, SFSTAT_UDBL_SHIFT, %g7
65	or		%g4, %g7, %g4
66	andcc		%g3, %g1, %g3		! UDBE_UE or UDBE_CE
67	be,pn		%xcc, 1f
68	 nop
69	mov		0x18, %g7
70	stxa		%g3, [%g7] ASI_UDB_ERROR_W
71	membar		#Sync
72
731:	/* Ok, now that we've latched the error state, clear the
74	 * sticky bits in the AFSR.
75	 */
76	stxa		%g4, [%g0] ASI_AFSR
77	membar		#Sync
78
79	rdpr		%tl, %g2
80	cmp		%g2, 1
81	rdpr		%pil, %g2
82	bleu,pt		%xcc, 1f
83	 wrpr		%g0, PIL_NORMAL_MAX, %pil
84
85	ba,pt		%xcc, etraptl1
86	 rd		%pc, %g7
87
88	ba,pt		%xcc, 2f
89	 nop
90
911:	ba,pt		%xcc, etrap_irq
92	 rd		%pc, %g7
93
942:
95#ifdef CONFIG_TRACE_IRQFLAGS
96	call	trace_hardirqs_off
97	 nop
98#endif
99	mov		%l4, %o1
100	mov		%l5, %o2
101	call		spitfire_access_error
102	 add		%sp, PTREGS_OFF, %o0
103	ba,pt		%xcc, rtrap
104	 nop
105	.size		__spitfire_access_error,.-__spitfire_access_error
106
107	/* This is the trap handler entry point for ECC correctable
108	 * errors.  They are corrected, but we listen for the trap so
109	 * that the event can be logged.
110	 *
111	 * Disrupting errors are either:
112	 * 1) single-bit ECC errors during UDB reads to system
113	 *    memory
114	 * 2) data parity errors during write-back events
115	 *
116	 * As far as I can make out from the manual, the CEE trap is
117	 * only for correctable errors during memory read accesses by
118	 * the front-end of the processor.
119	 *
120	 * The code below is only for trap level 1 CEE events, as it
121	 * is the only situation where we can safely record and log.
122	 * For trap level >1 we just clear the CE bit in the AFSR and
123	 * return.
124	 *
125	 * This is just like __spiftire_access_error above, but it
126	 * specifically handles correctable errors.  If an
127	 * uncorrectable error is indicated in the AFSR we will branch
128	 * directly above to __spitfire_access_error to handle it
129	 * instead.  Uncorrectable therefore takes priority over
130	 * correctable, and the error logging C code will notice this
131	 * case by inspecting the trap type.
132	 */
133	.type		__spitfire_cee_trap,#function
134__spitfire_cee_trap:
135	ldxa		[%g0] ASI_AFSR, %g4	! Get AFSR
136	mov		1, %g3
137	sllx		%g3, SFAFSR_UE_SHIFT, %g3
138	andcc		%g4, %g3, %g0		! Check for UE
139	bne,pn		%xcc, __spitfire_access_error
140	 nop
141
142	/* Ok, in this case we only have a correctable error.
143	 * Indicate we only wish to capture that state in register
144	 * %g1, and we only disable CE error reporting unlike UE
145	 * handling which disables all errors.
146	 */
147	ldxa		[%g0] ASI_ESTATE_ERROR_EN, %g3
148	andn		%g3, ESTATE_ERR_CE, %g3
149	stxa		%g3, [%g0] ASI_ESTATE_ERROR_EN
150	membar		#Sync
151
152	/* Preserve AFSR in %g4, indicate UDB state to capture in %g1 */
153	ba,pt		%xcc, __spitfire_cee_trap_continue
154	 mov		UDBE_CE, %g1
155	.size		__spitfire_cee_trap,.-__spitfire_cee_trap
156
157	.type		__spitfire_data_access_exception_tl1,#function
158__spitfire_data_access_exception_tl1:
159	rdpr		%pstate, %g4
160	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
161	mov		TLB_SFSR, %g3
162	mov		DMMU_SFAR, %g5
163	ldxa		[%g3] ASI_DMMU, %g4	! Get SFSR
164	ldxa		[%g5] ASI_DMMU, %g5	! Get SFAR
165	stxa		%g0, [%g3] ASI_DMMU	! Clear SFSR.FaultValid bit
166	membar		#Sync
167	rdpr		%tt, %g3
168	cmp		%g3, 0x80		! first win spill/fill trap
169	blu,pn		%xcc, 1f
170	 cmp		%g3, 0xff		! last win spill/fill trap
171	bgu,pn		%xcc, 1f
172	 nop
173	ba,pt		%xcc, winfix_dax
174	 rdpr		%tpc, %g3
1751:	sethi		%hi(109f), %g7
176	ba,pt		%xcc, etraptl1
177109:	 or		%g7, %lo(109b), %g7
178	mov		%l4, %o1
179	mov		%l5, %o2
180	call		spitfire_data_access_exception_tl1
181	 add		%sp, PTREGS_OFF, %o0
182	ba,pt		%xcc, rtrap
183	 nop
184	.size		__spitfire_data_access_exception_tl1,.-__spitfire_data_access_exception_tl1
185
186	.type		__spitfire_data_access_exception,#function
187__spitfire_data_access_exception:
188	rdpr		%pstate, %g4
189	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
190	mov		TLB_SFSR, %g3
191	mov		DMMU_SFAR, %g5
192	ldxa		[%g3] ASI_DMMU, %g4	! Get SFSR
193	ldxa		[%g5] ASI_DMMU, %g5	! Get SFAR
194	stxa		%g0, [%g3] ASI_DMMU	! Clear SFSR.FaultValid bit
195	membar		#Sync
196	sethi		%hi(109f), %g7
197	ba,pt		%xcc, etrap
198109:	 or		%g7, %lo(109b), %g7
199	mov		%l4, %o1
200	mov		%l5, %o2
201	call		spitfire_data_access_exception
202	 add		%sp, PTREGS_OFF, %o0
203	ba,pt		%xcc, rtrap
204	 nop
205	.size		__spitfire_data_access_exception,.-__spitfire_data_access_exception
206
207	.type		__spitfire_insn_access_exception_tl1,#function
208__spitfire_insn_access_exception_tl1:
209	rdpr		%pstate, %g4
210	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
211	mov		TLB_SFSR, %g3
212	ldxa		[%g3] ASI_IMMU, %g4	! Get SFSR
213	rdpr		%tpc, %g5		! IMMU has no SFAR, use TPC
214	stxa		%g0, [%g3] ASI_IMMU	! Clear FaultValid bit
215	membar		#Sync
216	sethi		%hi(109f), %g7
217	ba,pt		%xcc, etraptl1
218109:	 or		%g7, %lo(109b), %g7
219	mov		%l4, %o1
220	mov		%l5, %o2
221	call		spitfire_insn_access_exception_tl1
222	 add		%sp, PTREGS_OFF, %o0
223	ba,pt		%xcc, rtrap
224	 nop
225	.size		__spitfire_insn_access_exception_tl1,.-__spitfire_insn_access_exception_tl1
226
227	.type		__spitfire_insn_access_exception,#function
228__spitfire_insn_access_exception:
229	rdpr		%pstate, %g4
230	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
231	mov		TLB_SFSR, %g3
232	ldxa		[%g3] ASI_IMMU, %g4	! Get SFSR
233	rdpr		%tpc, %g5		! IMMU has no SFAR, use TPC
234	stxa		%g0, [%g3] ASI_IMMU	! Clear FaultValid bit
235	membar		#Sync
236	sethi		%hi(109f), %g7
237	ba,pt		%xcc, etrap
238109:	 or		%g7, %lo(109b), %g7
239	mov		%l4, %o1
240	mov		%l5, %o2
241	call		spitfire_insn_access_exception
242	 add		%sp, PTREGS_OFF, %o0
243	ba,pt		%xcc, rtrap
244	 nop
245	.size		__spitfire_insn_access_exception,.-__spitfire_insn_access_exception
246