drivers/misc/sgi-gru/gruhandles.c

   1 /*
   2  *              GRU KERNEL MCS INSTRUCTIONS
   3  *
   4  *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include "gru.h"
  23 #include "grulib.h"
  24 #include "grutables.h"
  25
  26 /* 10 sec */
  27 #ifdef CONFIG_IA64
  28 #include <asm/processor.h>
  29 #define GRU_OPERATION_TIMEOUT   (((cycles_t) local_cpu_data->itc_freq)*10)
  30 #define CLKS2NSEC(c)            ((c) *1000000000 / local_cpu_data->itc_freq)
  31 #else
  32 #include <asm/tsc.h>
  33 #define GRU_OPERATION_TIMEOUT   ((cycles_t) tsc_khz*10*1000)
  34 #define CLKS2NSEC(c)            ((c) * 1000000 / tsc_khz)
  35 #endif
  36
  37 /* Extract the status field from a kernel handle */
  38 #define GET_MSEG_HANDLE_STATUS(h)       (((*(unsigned long *)(h)) >> 16) & 3)
  39
  40 struct mcs_op_statistic mcs_op_statistics[mcsop_last];
  41
  42 static void update_mcs_stats(enum mcs_op op, unsigned long clks)
  43 {
  44         unsigned long nsec;
  45
  46         nsec = CLKS2NSEC(clks);
  47         atomic_long_inc(&mcs_op_statistics[op].count);
  48         atomic_long_add(nsec, &mcs_op_statistics[op].total);
  49         if (mcs_op_statistics[op].max < nsec)
  50                 mcs_op_statistics[op].max = nsec;
  51 }
  52
  53 static void start_instruction(void *h)
  54 {
  55         unsigned long *w0 = h;
  56
  57         wmb();          /* setting CMD/STATUS bits must be last */
  58         *w0 = *w0 | 0x20001;
  59         gru_flush_cache(h);
  60 }
  61
  62 static void report_instruction_timeout(void *h)
  63 {
  64         unsigned long goff = GSEGPOFF((unsigned long)h);
  65         char *id = "???";
  66
  67         if (TYPE_IS(CCH, goff))
  68                 id = "CCH";
  69         else if (TYPE_IS(TGH, goff))
  70                 id = "TGH";
  71         else if (TYPE_IS(TFH, goff))
  72                 id = "TFH";
  73
  74         panic(KERN_ALERT "GRU %p (%s) is malfunctioning\n", h, id);
  75 }
  76
  77 static int wait_instruction_complete(void *h, enum mcs_op opc)
  78 {
  79         int status;
  80         unsigned long start_time = get_cycles();
  81
  82         while (1) {
  83                 cpu_relax();
  84                 status = GET_MSEG_HANDLE_STATUS(h);
  85                 if (status != CCHSTATUS_ACTIVE)
  86                         break;
  87                 if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time)) {
  88                         report_instruction_timeout(h);
  89                         start_time = get_cycles();
  90                 }
  91         }
  92         if (gru_options & OPT_STATS)
  93                 update_mcs_stats(opc, get_cycles() - start_time);
  94         return status;
  95 }
  96
  97 int cch_allocate(struct gru_context_configuration_handle *cch)
  98 {
  99         int ret;
 100
 101         cch->opc = CCHOP_ALLOCATE;
 102         start_instruction(cch);
 103         ret = wait_instruction_complete(cch, cchop_allocate);
 104
 105         /*
 106          * Stop speculation into the GSEG being mapped by the previous ALLOCATE.
 107          * The GSEG memory does not exist until the ALLOCATE completes.
 108          */
 109         sync_core();
 110         return ret;
 111 }
 112
 113 int cch_start(struct gru_context_configuration_handle *cch)
 114 {
 115         cch->opc = CCHOP_START;
 116         start_instruction(cch);
 117         return wait_instruction_complete(cch, cchop_start);
 118 }
 119
 120 int cch_interrupt(struct gru_context_configuration_handle *cch)
 121 {
 122         cch->opc = CCHOP_INTERRUPT;
 123         start_instruction(cch);
 124         return wait_instruction_complete(cch, cchop_interrupt);
 125 }
 126
 127 int cch_deallocate(struct gru_context_configuration_handle *cch)
 128 {
 129         int ret;
 130
 131         cch->opc = CCHOP_DEALLOCATE;
 132         start_instruction(cch);
 133         ret = wait_instruction_complete(cch, cchop_deallocate);
 134
 135         /*
 136          * Stop speculation into the GSEG being unmapped by the previous
 137          * DEALLOCATE.
 138          */
 139         sync_core();
 140         return ret;
 141 }
 142
 143 int cch_interrupt_sync(struct gru_context_configuration_handle
 144                                      *cch)
 145 {
 146         cch->opc = CCHOP_INTERRUPT_SYNC;
 147         start_instruction(cch);
 148         return wait_instruction_complete(cch, cchop_interrupt_sync);
 149 }
 150
 151 int tgh_invalidate(struct gru_tlb_global_handle *tgh,
 152                                  unsigned long vaddr, unsigned long vaddrmask,
 153                                  int asid, int pagesize, int global, int n,
 154                                  unsigned short ctxbitmap)
 155 {
 156         tgh->vaddr = vaddr;
 157         tgh->asid = asid;
 158         tgh->pagesize = pagesize;
 159         tgh->n = n;
 160         tgh->global = global;
 161         tgh->vaddrmask = vaddrmask;
 162         tgh->ctxbitmap = ctxbitmap;
 163         tgh->opc = TGHOP_TLBINV;
 164         start_instruction(tgh);
 165         return wait_instruction_complete(tgh, tghop_invalidate);
 166 }
 167
 168 int tfh_write_only(struct gru_tlb_fault_handle *tfh,
 169                                   unsigned long paddr, int gaa,
 170                                   unsigned long vaddr, int asid, int dirty,
 171                                   int pagesize)
 172 {
 173         tfh->fillasid = asid;
 174         tfh->fillvaddr = vaddr;
 175         tfh->pfn = paddr >> GRU_PADDR_SHIFT;
 176         tfh->gaa = gaa;
 177         tfh->dirty = dirty;
 178         tfh->pagesize = pagesize;
 179         tfh->opc = TFHOP_WRITE_ONLY;
 180         start_instruction(tfh);
 181         return wait_instruction_complete(tfh, tfhop_write_only);
 182 }
 183
 184 void tfh_write_restart(struct gru_tlb_fault_handle *tfh,
 185                                      unsigned long paddr, int gaa,
 186                                      unsigned long vaddr, int asid, int dirty,
 187                                      int pagesize)
 188 {
 189         tfh->fillasid = asid;
 190         tfh->fillvaddr = vaddr;
 191         tfh->pfn = paddr >> GRU_PADDR_SHIFT;
 192         tfh->gaa = gaa;
 193         tfh->dirty = dirty;
 194         tfh->pagesize = pagesize;
 195         tfh->opc = TFHOP_WRITE_RESTART;
 196         start_instruction(tfh);
 197 }
 198
 199 void tfh_user_polling_mode(struct gru_tlb_fault_handle *tfh)
 200 {
 201         tfh->opc = TFHOP_USER_POLLING_MODE;
 202         start_instruction(tfh);
 203 }
 204
 205 void tfh_exception(struct gru_tlb_fault_handle *tfh)
 206 {
 207         tfh->opc = TFHOP_EXCEPTION;
 208         start_instruction(tfh);
 209 }
 210