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   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2000-2005 Silicon Graphics, Inc. All rights reserved.
   7  */
   8
   9 #include <asm/types.h>
  10 #include <asm/sn/shub_mmr.h>
  11
  12 #define DEADLOCKBIT     SH_PIO_WRITE_STATUS_WRITE_DEADLOCK_SHFT
  13 #define WRITECOUNTMASK  SH_PIO_WRITE_STATUS_PENDING_WRITE_COUNT_MASK
  14 #define ALIAS_OFFSET    8
  15
  16
  17         .global sn2_ptc_deadlock_recovery_core
  18         .proc   sn2_ptc_deadlock_recovery_core
  19
  20 sn2_ptc_deadlock_recovery_core:
  21         .regstk 6,0,0,0
  22
  23         ptc0     = in0
  24         data0    = in1
  25         ptc1     = in2
  26         data1    = in3
  27         piowc    = in4
  28         zeroval  = in5
  29         piowcphy = r30
  30         psrsave  = r2
  31         scr1     = r16
  32         scr2     = r17
  33         mask     = r18
  34
  35
  36         extr.u  piowcphy=piowc,0,61;;   // Convert piowc to uncached physical address
  37         dep     piowcphy=-1,piowcphy,63,1
  38         movl    mask=WRITECOUNTMASK
  39         mov     r8=r0
  40
  41 1:
  42         cmp.ne  p8,p9=r0,ptc1           // Test for shub type (ptc1 non-null on shub1)
  43                                         // p8 = 1 if shub1, p9 = 1 if shub2
  44
  45         add     scr2=ALIAS_OFFSET,piowc // Address of WRITE_STATUS alias register
  46         mov     scr1=7;;                // Clear DEADLOCK, WRITE_ERROR, MULTI_WRITE_ERROR
  47 (p8)    st8.rel [scr2]=scr1;;
  48 (p9)    ld8.acq scr1=[scr2];;
  49
  50 5:      ld8.acq scr1=[piowc];;          // Wait for PIOs to complete.
  51         hint    @pause
  52         and     scr2=scr1,mask;;        // mask of writecount bits
  53         cmp.ne  p6,p0=zeroval,scr2
  54 (p6)    br.cond.sptk 5b
  55
  56
  57
  58         ////////////// BEGIN PHYSICAL MODE ////////////////////
  59         mov psrsave=psr                 // Disable IC (no PMIs)
  60         rsm psr.i | psr.dt | psr.ic;;
  61         srlz.i;;
  62
  63         st8.rel [ptc0]=data0            // Write PTC0 & wait for completion.
  64
  65 5:      ld8.acq scr1=[piowcphy];;       // Wait for PIOs to complete.
  66         hint    @pause
  67         and     scr2=scr1,mask;;        // mask of writecount bits
  68         cmp.ne  p6,p0=zeroval,scr2
  69 (p6)    br.cond.sptk 5b;;
  70
  71         tbit.nz p8,p7=scr1,DEADLOCKBIT;;// Test for DEADLOCK
  72 (p7)    cmp.ne p7,p0=r0,ptc1;;          // Test for non-null ptc1
  73
  74 (p7)    st8.rel [ptc1]=data1;;          // Now write PTC1.
  75
  76 5:      ld8.acq scr1=[piowcphy];;       // Wait for PIOs to complete.
  77         hint    @pause
  78         and     scr2=scr1,mask;;        // mask of writecount bits
  79         cmp.ne  p6,p0=zeroval,scr2
  80 (p6)    br.cond.sptk 5b
  81
  82         tbit.nz p8,p0=scr1,DEADLOCKBIT;;// Test for DEADLOCK
  83
  84         mov psr.l=psrsave;;             // Reenable IC
  85         srlz.i;;
  86         ////////////// END   PHYSICAL MODE ////////////////////
  87
  88 (p8)    add     r8=1,r8
  89 (p8)    br.cond.spnt 1b;;               // Repeat if DEADLOCK occurred.
  90
  91         br.ret.sptk     rp
  92         .endp sn2_ptc_deadlock_recovery_core