xref: /openbmc/linux/arch/sparc/kernel/spiterrs.S (revision 7587eb18)
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,a,pt		%xcc, 2f
89
901:	ba,pt		%xcc, etrap_irq
91	 rd		%pc, %g7
92
932:
94#ifdef CONFIG_TRACE_IRQFLAGS
95	call	trace_hardirqs_off
96	 nop
97#endif
98	mov		%l4, %o1
99	mov		%l5, %o2
100	call		spitfire_access_error
101	 add		%sp, PTREGS_OFF, %o0
102	ba,a,pt		%xcc, rtrap
103	.size		__spitfire_access_error,.-__spitfire_access_error
104
105	/* This is the trap handler entry point for ECC correctable
106	 * errors.  They are corrected, but we listen for the trap so
107	 * that the event can be logged.
108	 *
109	 * Disrupting errors are either:
110	 * 1) single-bit ECC errors during UDB reads to system
111	 *    memory
112	 * 2) data parity errors during write-back events
113	 *
114	 * As far as I can make out from the manual, the CEE trap is
115	 * only for correctable errors during memory read accesses by
116	 * the front-end of the processor.
117	 *
118	 * The code below is only for trap level 1 CEE events, as it
119	 * is the only situation where we can safely record and log.
120	 * For trap level >1 we just clear the CE bit in the AFSR and
121	 * return.
122	 *
123	 * This is just like __spiftire_access_error above, but it
124	 * specifically handles correctable errors.  If an
125	 * uncorrectable error is indicated in the AFSR we will branch
126	 * directly above to __spitfire_access_error to handle it
127	 * instead.  Uncorrectable therefore takes priority over
128	 * correctable, and the error logging C code will notice this
129	 * case by inspecting the trap type.
130	 */
131	.type		__spitfire_cee_trap,#function
132__spitfire_cee_trap:
133	ldxa		[%g0] ASI_AFSR, %g4	! Get AFSR
134	mov		1, %g3
135	sllx		%g3, SFAFSR_UE_SHIFT, %g3
136	andcc		%g4, %g3, %g0		! Check for UE
137	bne,pn		%xcc, __spitfire_access_error
138	 nop
139
140	/* Ok, in this case we only have a correctable error.
141	 * Indicate we only wish to capture that state in register
142	 * %g1, and we only disable CE error reporting unlike UE
143	 * handling which disables all errors.
144	 */
145	ldxa		[%g0] ASI_ESTATE_ERROR_EN, %g3
146	andn		%g3, ESTATE_ERR_CE, %g3
147	stxa		%g3, [%g0] ASI_ESTATE_ERROR_EN
148	membar		#Sync
149
150	/* Preserve AFSR in %g4, indicate UDB state to capture in %g1 */
151	ba,pt		%xcc, __spitfire_cee_trap_continue
152	 mov		UDBE_CE, %g1
153	.size		__spitfire_cee_trap,.-__spitfire_cee_trap
154
155	.type		__spitfire_data_access_exception_tl1,#function
156__spitfire_data_access_exception_tl1:
157	rdpr		%pstate, %g4
158	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
159	mov		TLB_SFSR, %g3
160	mov		DMMU_SFAR, %g5
161	ldxa		[%g3] ASI_DMMU, %g4	! Get SFSR
162	ldxa		[%g5] ASI_DMMU, %g5	! Get SFAR
163	stxa		%g0, [%g3] ASI_DMMU	! Clear SFSR.FaultValid bit
164	membar		#Sync
165	rdpr		%tt, %g3
166	cmp		%g3, 0x80		! first win spill/fill trap
167	blu,pn		%xcc, 1f
168	 cmp		%g3, 0xff		! last win spill/fill trap
169	bgu,pn		%xcc, 1f
170	 nop
171	ba,pt		%xcc, winfix_dax
172	 rdpr		%tpc, %g3
1731:	sethi		%hi(109f), %g7
174	ba,pt		%xcc, etraptl1
175109:	 or		%g7, %lo(109b), %g7
176	mov		%l4, %o1
177	mov		%l5, %o2
178	call		spitfire_data_access_exception_tl1
179	 add		%sp, PTREGS_OFF, %o0
180	ba,a,pt		%xcc, rtrap
181	.size		__spitfire_data_access_exception_tl1,.-__spitfire_data_access_exception_tl1
182
183	.type		__spitfire_data_access_exception,#function
184__spitfire_data_access_exception:
185	rdpr		%pstate, %g4
186	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
187	mov		TLB_SFSR, %g3
188	mov		DMMU_SFAR, %g5
189	ldxa		[%g3] ASI_DMMU, %g4	! Get SFSR
190	ldxa		[%g5] ASI_DMMU, %g5	! Get SFAR
191	stxa		%g0, [%g3] ASI_DMMU	! Clear SFSR.FaultValid bit
192	membar		#Sync
193	sethi		%hi(109f), %g7
194	ba,pt		%xcc, etrap
195109:	 or		%g7, %lo(109b), %g7
196	mov		%l4, %o1
197	mov		%l5, %o2
198	call		spitfire_data_access_exception
199	 add		%sp, PTREGS_OFF, %o0
200	ba,a,pt		%xcc, rtrap
201	.size		__spitfire_data_access_exception,.-__spitfire_data_access_exception
202
203	.type		__spitfire_insn_access_exception_tl1,#function
204__spitfire_insn_access_exception_tl1:
205	rdpr		%pstate, %g4
206	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
207	mov		TLB_SFSR, %g3
208	ldxa		[%g3] ASI_IMMU, %g4	! Get SFSR
209	rdpr		%tpc, %g5		! IMMU has no SFAR, use TPC
210	stxa		%g0, [%g3] ASI_IMMU	! Clear FaultValid bit
211	membar		#Sync
212	sethi		%hi(109f), %g7
213	ba,pt		%xcc, etraptl1
214109:	 or		%g7, %lo(109b), %g7
215	mov		%l4, %o1
216	mov		%l5, %o2
217	call		spitfire_insn_access_exception_tl1
218	 add		%sp, PTREGS_OFF, %o0
219	ba,a,pt		%xcc, rtrap
220	.size		__spitfire_insn_access_exception_tl1,.-__spitfire_insn_access_exception_tl1
221
222	.type		__spitfire_insn_access_exception,#function
223__spitfire_insn_access_exception:
224	rdpr		%pstate, %g4
225	wrpr		%g4, PSTATE_MG|PSTATE_AG, %pstate
226	mov		TLB_SFSR, %g3
227	ldxa		[%g3] ASI_IMMU, %g4	! Get SFSR
228	rdpr		%tpc, %g5		! IMMU has no SFAR, use TPC
229	stxa		%g0, [%g3] ASI_IMMU	! Clear FaultValid bit
230	membar		#Sync
231	sethi		%hi(109f), %g7
232	ba,pt		%xcc, etrap
233109:	 or		%g7, %lo(109b), %g7
234	mov		%l4, %o1
235	mov		%l5, %o2
236	call		spitfire_insn_access_exception
237	 add		%sp, PTREGS_OFF, %o0
238	ba,a,pt		%xcc, rtrap
239	.size		__spitfire_insn_access_exception,.-__spitfire_insn_access_exception
240