[Skiboot] [PATCH] external/mambo: improve helper for machine checks

[Balbir Singh]

On Tue, 17 Apr 2018 16:28:19 +1000
Nicholas Piggin <npiggin at gmail.com> wrote:

> Improve workarounds for stop injection, because mambo often will
> trigger on 0x104/204 when injecting sreset/mces.
> 
> This also adds a workaround to skip injecting on reservations to
> avoid infinite loops when doing inject_mce_step.
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---
>  external/mambo/mambo_utils.tcl | 62 +++++++++++++++++++++++++++++-----
>  1 file changed, 53 insertions(+), 9 deletions(-)
> 
> diff --git a/external/mambo/mambo_utils.tcl b/external/mambo/mambo_utils.tcl
> index 7a27f0f4..6cbb222a 100644
> --- a/external/mambo/mambo_utils.tcl
> +++ b/external/mambo/mambo_utils.tcl
> @@ -378,6 +378,7 @@ proc sreset_trigger { args } {
>      variable SRR1
>  
>      mysim trigger clear pc 0x100
> +    mysim trigger clear pc 0x104
>      set s [expr [mysim cpu 0 display spr srr1] & ~0x00000000003c0002]
>      set SRR1 [expr $SRR1 | $s]
>      mysim cpu 0 set spr srr1 $SRR1
> @@ -410,14 +411,23 @@ proc exc_sreset { } {
>  
>      if { [current_insn] in { "stop" "nap" "sleep" "winkle" } } {
>          # mambo has a quirk that interrupts from idle wake immediately
> +        # and go over current instruction.
>          mysim trigger set pc 0x100 "sreset_trigger"
> -        mysim cpu 0 interrupt MachineCheck
> -	# XXX: only trigger if pc is 0x100
> -	sreset_trigger
> +        mysim trigger set pc 0x104 "sreset_trigger"
> +        mysim cpu 0 interrupt SystemReset
>      } else {
>          mysim trigger set pc 0x100 "sreset_trigger"
> +        mysim trigger set pc 0x104 "sreset_trigger"
>          mysim cpu 0 interrupt SystemReset
>      }
> +
> +    # sleep and sometimes other types of interrupts do not trigger 0x100
> +    if { [expr [mysim cpu 0 display spr pc] == 0x100 ] } {
> +	sreset_trigger
> +    }
> +    if { [expr [mysim cpu 0 display spr pc] == 0x104 ] } {
> +	sreset_trigger
> +    }
>  }
>  
>  proc mce_trigger { args } {
> @@ -426,12 +436,13 @@ proc mce_trigger { args } {
>      variable DAR
>  
>      mysim trigger clear pc 0x200
> +    mysim trigger clear pc 0x204
>  
>      set s [expr [mysim cpu 0 display spr srr1] & ~0x00000000801f0002]
>      set SRR1 [expr $SRR1 | $s]
>      mysim cpu 0 set spr srr1 $SRR1
>      mysim cpu 0 set spr dsisr $DSISR
> -    mysim cpu 0 set spr dar $DAR
> +    mysim cpu 0 set spr dar $DAR ; list
>  }
>  
>  #
> @@ -451,6 +462,8 @@ proc exc_mce { { d_side 0 } { cause 0x5 } { recoverable 1 } } {
>      variable DSISR
>      variable DAR
>  
> +#    puts "INJECTING MCE"
> +
>      # In case of recoverable MCE, idle wakeup always sets RI, others get
>      # RI from current environment. For unrecoverable, RI would always be
>      # clear by hardware.
> @@ -466,7 +479,6 @@ proc exc_mce { { d_side 0 } { cause 0x5 } { recoverable 1 } } {
>          set msr_ri 0x0
>      }
>  
> -    # recoverable d-side SLB multihit
>      if { $d_side } {
>          set is_dside 1
>          set SRR1_mc_cause 0x0
> @@ -489,14 +501,23 @@ proc exc_mce { { d_side 0 } { cause 0x5 } { recoverable 1 } } {
>  
>      if { [current_insn] in { "stop" "nap" "sleep" "winkle" } } {
>          # mambo has a quirk that interrupts from idle wake immediately
> +        # and go over current instruction.
>          mysim trigger set pc 0x200 "mce_trigger"
> +        mysim trigger set pc 0x204 "mce_trigger"
>          mysim cpu 0 interrupt MachineCheck
> -	# XXX: only trigger if pc is 0x200
> -	mce_trigger
>      } else {
>          mysim trigger set pc 0x200 "mce_trigger"
> +        mysim trigger set pc 0x204 "mce_trigger"
>          mysim cpu 0 interrupt MachineCheck
>      }
> +
> +    # sleep and sometimes other types of interrupts do not trigger 0x200
> +    if { [expr [mysim cpu 0 display spr pc] == 0x200 ] } {
> +	mce_trigger
> +    }
> +    if { [expr [mysim cpu 0 display spr pc] == 0x204 ] } {
> +	mce_trigger
> +    }
>  }
>  

Thesse bits look fine to me

Acked-by: Balbir Singh <bsingharora at gmail.com>