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-rw-r--r--arch/sparc/kernel/spiterrs.S241
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diff --git a/arch/sparc/kernel/spiterrs.S b/arch/sparc/kernel/spiterrs.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+ /* We need to carefully read the error status, ACK the errors,
+ * prevent recursive traps, and pass the information on to C
+ * code for logging.
+ *
+ * We pass the AFAR in as-is, and we encode the status
+ * information as described in asm-sparc64/sfafsr.h
+ */
+ .type __spitfire_access_error,#function
+__spitfire_access_error:
+ /* Disable ESTATE error reporting so that we do not take
+ * recursive traps and RED state the processor.
+ */
+ stxa %g0, [%g0] ASI_ESTATE_ERROR_EN
+ membar #Sync
+
+ mov UDBE_UE, %g1
+ ldxa [%g0] ASI_AFSR, %g4 ! Get AFSR
+
+ /* __spitfire_cee_trap branches here with AFSR in %g4 and
+ * UDBE_CE in %g1. It only clears ESTATE_ERR_CE in the ESTATE
+ * Error Enable register.
+ */
+__spitfire_cee_trap_continue:
+ ldxa [%g0] ASI_AFAR, %g5 ! Get AFAR
+
+ rdpr %tt, %g3
+ and %g3, 0x1ff, %g3 ! Paranoia
+ sllx %g3, SFSTAT_TRAP_TYPE_SHIFT, %g3
+ or %g4, %g3, %g4
+ rdpr %tl, %g3
+ cmp %g3, 1
+ mov 1, %g3
+ bleu %xcc, 1f
+ sllx %g3, SFSTAT_TL_GT_ONE_SHIFT, %g3
+
+ or %g4, %g3, %g4
+
+ /* Read in the UDB error register state, clearing the sticky
+ * error bits as-needed. We only clear them if the UE bit is
+ * set. Likewise, __spitfire_cee_trap below will only do so
+ * if the CE bit is set.
+ *
+ * NOTE: UltraSparc-I/II have high and low UDB error
+ * registers, corresponding to the two UDB units
+ * present on those chips. UltraSparc-IIi only
+ * has a single UDB, called "SDB" in the manual.
+ * For IIi the upper UDB register always reads
+ * as zero so for our purposes things will just
+ * work with the checks below.
+ */
+1: ldxa [%g0] ASI_UDBH_ERROR_R, %g3
+ and %g3, 0x3ff, %g7 ! Paranoia
+ sllx %g7, SFSTAT_UDBH_SHIFT, %g7
+ or %g4, %g7, %g4
+ andcc %g3, %g1, %g3 ! UDBE_UE or UDBE_CE
+ be,pn %xcc, 1f
+ nop
+ stxa %g3, [%g0] ASI_UDB_ERROR_W
+ membar #Sync
+
+1: mov 0x18, %g3
+ ldxa [%g3] ASI_UDBL_ERROR_R, %g3
+ and %g3, 0x3ff, %g7 ! Paranoia
+ sllx %g7, SFSTAT_UDBL_SHIFT, %g7
+ or %g4, %g7, %g4
+ andcc %g3, %g1, %g3 ! UDBE_UE or UDBE_CE
+ be,pn %xcc, 1f
+ nop
+ mov 0x18, %g7
+ stxa %g3, [%g7] ASI_UDB_ERROR_W
+ membar #Sync
+
+1: /* Ok, now that we've latched the error state, clear the
+ * sticky bits in the AFSR.
+ */
+ stxa %g4, [%g0] ASI_AFSR
+ membar #Sync
+
+ rdpr %tl, %g2
+ cmp %g2, 1
+ rdpr %pil, %g2
+ bleu,pt %xcc, 1f
+ wrpr %g0, PIL_NORMAL_MAX, %pil
+
+ ba,pt %xcc, etraptl1
+ rd %pc, %g7
+
+ ba,a,pt %xcc, 2f
+ nop
+
+1: ba,pt %xcc, etrap_irq
+ rd %pc, %g7
+
+2:
+#ifdef CONFIG_TRACE_IRQFLAGS
+ call trace_hardirqs_off
+ nop
+#endif
+ mov %l4, %o1
+ mov %l5, %o2
+ call spitfire_access_error
+ add %sp, PTREGS_OFF, %o0
+ ba,a,pt %xcc, rtrap
+ .size __spitfire_access_error,.-__spitfire_access_error
+
+ /* This is the trap handler entry point for ECC correctable
+ * errors. They are corrected, but we listen for the trap so
+ * that the event can be logged.
+ *
+ * Disrupting errors are either:
+ * 1) single-bit ECC errors during UDB reads to system
+ * memory
+ * 2) data parity errors during write-back events
+ *
+ * As far as I can make out from the manual, the CEE trap is
+ * only for correctable errors during memory read accesses by
+ * the front-end of the processor.
+ *
+ * The code below is only for trap level 1 CEE events, as it
+ * is the only situation where we can safely record and log.
+ * For trap level >1 we just clear the CE bit in the AFSR and
+ * return.
+ *
+ * This is just like __spiftire_access_error above, but it
+ * specifically handles correctable errors. If an
+ * uncorrectable error is indicated in the AFSR we will branch
+ * directly above to __spitfire_access_error to handle it
+ * instead. Uncorrectable therefore takes priority over
+ * correctable, and the error logging C code will notice this
+ * case by inspecting the trap type.
+ */
+ .type __spitfire_cee_trap,#function
+__spitfire_cee_trap:
+ ldxa [%g0] ASI_AFSR, %g4 ! Get AFSR
+ mov 1, %g3
+ sllx %g3, SFAFSR_UE_SHIFT, %g3
+ andcc %g4, %g3, %g0 ! Check for UE
+ bne,pn %xcc, __spitfire_access_error
+ nop
+
+ /* Ok, in this case we only have a correctable error.
+ * Indicate we only wish to capture that state in register
+ * %g1, and we only disable CE error reporting unlike UE
+ * handling which disables all errors.
+ */
+ ldxa [%g0] ASI_ESTATE_ERROR_EN, %g3
+ andn %g3, ESTATE_ERR_CE, %g3
+ stxa %g3, [%g0] ASI_ESTATE_ERROR_EN
+ membar #Sync
+
+ /* Preserve AFSR in %g4, indicate UDB state to capture in %g1 */
+ ba,pt %xcc, __spitfire_cee_trap_continue
+ mov UDBE_CE, %g1
+ .size __spitfire_cee_trap,.-__spitfire_cee_trap
+
+ .type __spitfire_data_access_exception_tl1,#function
+__spitfire_data_access_exception_tl1:
+ rdpr %pstate, %g4
+ wrpr %g4, PSTATE_MG|PSTATE_AG, %pstate
+ mov TLB_SFSR, %g3
+ mov DMMU_SFAR, %g5
+ ldxa [%g3] ASI_DMMU, %g4 ! Get SFSR
+ ldxa [%g5] ASI_DMMU, %g5 ! Get SFAR
+ stxa %g0, [%g3] ASI_DMMU ! Clear SFSR.FaultValid bit
+ membar #Sync
+ rdpr %tt, %g3
+ cmp %g3, 0x80 ! first win spill/fill trap
+ blu,pn %xcc, 1f
+ cmp %g3, 0xff ! last win spill/fill trap
+ bgu,pn %xcc, 1f
+ nop
+ ba,pt %xcc, winfix_dax
+ rdpr %tpc, %g3
+1: sethi %hi(109f), %g7
+ ba,pt %xcc, etraptl1
+109: or %g7, %lo(109b), %g7
+ mov %l4, %o1
+ mov %l5, %o2
+ call spitfire_data_access_exception_tl1
+ add %sp, PTREGS_OFF, %o0
+ ba,a,pt %xcc, rtrap
+ .size __spitfire_data_access_exception_tl1,.-__spitfire_data_access_exception_tl1
+
+ .type __spitfire_data_access_exception,#function
+__spitfire_data_access_exception:
+ rdpr %pstate, %g4
+ wrpr %g4, PSTATE_MG|PSTATE_AG, %pstate
+ mov TLB_SFSR, %g3
+ mov DMMU_SFAR, %g5
+ ldxa [%g3] ASI_DMMU, %g4 ! Get SFSR
+ ldxa [%g5] ASI_DMMU, %g5 ! Get SFAR
+ stxa %g0, [%g3] ASI_DMMU ! Clear SFSR.FaultValid bit
+ membar #Sync
+ sethi %hi(109f), %g7
+ ba,pt %xcc, etrap
+109: or %g7, %lo(109b), %g7
+ mov %l4, %o1
+ mov %l5, %o2
+ call spitfire_data_access_exception
+ add %sp, PTREGS_OFF, %o0
+ ba,a,pt %xcc, rtrap
+ .size __spitfire_data_access_exception,.-__spitfire_data_access_exception
+
+ .type __spitfire_insn_access_exception_tl1,#function
+__spitfire_insn_access_exception_tl1:
+ rdpr %pstate, %g4
+ wrpr %g4, PSTATE_MG|PSTATE_AG, %pstate
+ mov TLB_SFSR, %g3
+ ldxa [%g3] ASI_IMMU, %g4 ! Get SFSR
+ rdpr %tpc, %g5 ! IMMU has no SFAR, use TPC
+ stxa %g0, [%g3] ASI_IMMU ! Clear FaultValid bit
+ membar #Sync
+ sethi %hi(109f), %g7
+ ba,pt %xcc, etraptl1
+109: or %g7, %lo(109b), %g7
+ mov %l4, %o1
+ mov %l5, %o2
+ call spitfire_insn_access_exception_tl1
+ add %sp, PTREGS_OFF, %o0
+ ba,a,pt %xcc, rtrap
+ .size __spitfire_insn_access_exception_tl1,.-__spitfire_insn_access_exception_tl1
+
+ .type __spitfire_insn_access_exception,#function
+__spitfire_insn_access_exception:
+ rdpr %pstate, %g4
+ wrpr %g4, PSTATE_MG|PSTATE_AG, %pstate
+ mov TLB_SFSR, %g3
+ ldxa [%g3] ASI_IMMU, %g4 ! Get SFSR
+ rdpr %tpc, %g5 ! IMMU has no SFAR, use TPC
+ stxa %g0, [%g3] ASI_IMMU ! Clear FaultValid bit
+ membar #Sync
+ sethi %hi(109f), %g7
+ ba,pt %xcc, etrap
+109: or %g7, %lo(109b), %g7
+ mov %l4, %o1
+ mov %l5, %o2
+ call spitfire_insn_access_exception
+ add %sp, PTREGS_OFF, %o0
+ ba,a,pt %xcc, rtrap
+ .size __spitfire_insn_access_exception,.-__spitfire_insn_access_exception