LXR linux/drivers/misc/sgi-gru/gruhandles.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *              GRU KERNEL MCS INSTRUCTIONS
   4 *
   5 *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
   6 */
   7
   8#include <linux/kernel.h>
   9#include "gru.h"
  10#include "grulib.h"
  11#include "grutables.h"
  12
  13/* 10 sec */
  14#ifdef CONFIG_IA64
  15#include <asm/processor.h>
  16#define GRU_OPERATION_TIMEOUT   (((cycles_t) local_cpu_data->itc_freq)*10)
  17#define CLKS2NSEC(c)            ((c) *1000000000 / local_cpu_data->itc_freq)
  18#else
  19#include <asm/tsc.h>
  20#define GRU_OPERATION_TIMEOUT   ((cycles_t) tsc_khz*10*1000)
  21#define CLKS2NSEC(c)            ((c) * 1000000 / tsc_khz)
  22#endif
  23
  24/* Extract the status field from a kernel handle */
  25#define GET_MSEG_HANDLE_STATUS(h)       (((*(unsigned long *)(h)) >> 16) & 3)
  26
  27struct mcs_op_statistic mcs_op_statistics[mcsop_last];
  28
  29static void update_mcs_stats(enum mcs_op op, unsigned long clks)
  30{
  31        unsigned long nsec;
  32
  33        nsec = CLKS2NSEC(clks);
  34        atomic_long_inc(&mcs_op_statistics[op].count);
  35        atomic_long_add(nsec, &mcs_op_statistics[op].total);
  36        if (mcs_op_statistics[op].max < nsec)
  37                mcs_op_statistics[op].max = nsec;
  38}
  39
  40static void start_instruction(void *h)
  41{
  42        unsigned long *w0 = h;
  43
  44        wmb();          /* setting CMD/STATUS bits must be last */
  45        *w0 = *w0 | 0x20001;
  46        gru_flush_cache(h);
  47}
  48
  49static void report_instruction_timeout(void *h)
  50{
  51        unsigned long goff = GSEGPOFF((unsigned long)h);
  52        char *id = "???";
  53
  54        if (TYPE_IS(CCH, goff))
  55                id = "CCH";
  56        else if (TYPE_IS(TGH, goff))
  57                id = "TGH";
  58        else if (TYPE_IS(TFH, goff))
  59                id = "TFH";
  60
  61        panic(KERN_ALERT "GRU %p (%s) is malfunctioning\n", h, id);
  62}
  63
  64static int wait_instruction_complete(void *h, enum mcs_op opc)
  65{
  66        int status;
  67        unsigned long start_time = get_cycles();
  68
  69        while (1) {
  70                cpu_relax();
  71                status = GET_MSEG_HANDLE_STATUS(h);
  72                if (status != CCHSTATUS_ACTIVE)
  73                        break;
  74                if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time)) {
  75                        report_instruction_timeout(h);
  76                        start_time = get_cycles();
  77                }
  78        }
  79        if (gru_options & OPT_STATS)
  80                update_mcs_stats(opc, get_cycles() - start_time);
  81        return status;
  82}
  83
  84int cch_allocate(struct gru_context_configuration_handle *cch)
  85{
  86        int ret;
  87
  88        cch->opc = CCHOP_ALLOCATE;
  89        start_instruction(cch);
  90        ret = wait_instruction_complete(cch, cchop_allocate);
  91
  92        /*
  93         * Stop speculation into the GSEG being mapped by the previous ALLOCATE.
  94         * The GSEG memory does not exist until the ALLOCATE completes.
  95         */
  96        sync_core();
  97        return ret;
  98}
  99
 100int cch_start(struct gru_context_configuration_handle *cch)
 101{
 102        cch->opc = CCHOP_START;
 103        start_instruction(cch);
 104        return wait_instruction_complete(cch, cchop_start);
 105}
 106
 107int cch_interrupt(struct gru_context_configuration_handle *cch)
 108{
 109        cch->opc = CCHOP_INTERRUPT;
 110        start_instruction(cch);
 111        return wait_instruction_complete(cch, cchop_interrupt);
 112}
 113
 114int cch_deallocate(struct gru_context_configuration_handle *cch)
 115{
 116        int ret;
 117
 118        cch->opc = CCHOP_DEALLOCATE;
 119        start_instruction(cch);
 120        ret = wait_instruction_complete(cch, cchop_deallocate);
 121
 122        /*
 123         * Stop speculation into the GSEG being unmapped by the previous
 124         * DEALLOCATE.
 125         */
 126        sync_core();
 127        return ret;
 128}
 129
 130int cch_interrupt_sync(struct gru_context_configuration_handle
 131                                     *cch)
 132{
 133        cch->opc = CCHOP_INTERRUPT_SYNC;
 134        start_instruction(cch);
 135        return wait_instruction_complete(cch, cchop_interrupt_sync);
 136}
 137
 138int tgh_invalidate(struct gru_tlb_global_handle *tgh,
 139                                 unsigned long vaddr, unsigned long vaddrmask,
 140                                 int asid, int pagesize, int global, int n,
 141                                 unsigned short ctxbitmap)
 142{
 143        tgh->vaddr = vaddr;
 144        tgh->asid = asid;
 145        tgh->pagesize = pagesize;
 146        tgh->n = n;
 147        tgh->global = global;
 148        tgh->vaddrmask = vaddrmask;
 149        tgh->ctxbitmap = ctxbitmap;
 150        tgh->opc = TGHOP_TLBINV;
 151        start_instruction(tgh);
 152        return wait_instruction_complete(tgh, tghop_invalidate);
 153}
 154
 155int tfh_write_only(struct gru_tlb_fault_handle *tfh,
 156                                  unsigned long paddr, int gaa,
 157                                  unsigned long vaddr, int asid, int dirty,
 158                                  int pagesize)
 159{
 160        tfh->fillasid = asid;
 161        tfh->fillvaddr = vaddr;
 162        tfh->pfn = paddr >> GRU_PADDR_SHIFT;
 163        tfh->gaa = gaa;
 164        tfh->dirty = dirty;
 165        tfh->pagesize = pagesize;
 166        tfh->opc = TFHOP_WRITE_ONLY;
 167        start_instruction(tfh);
 168        return wait_instruction_complete(tfh, tfhop_write_only);
 169}
 170
 171void tfh_write_restart(struct gru_tlb_fault_handle *tfh,
 172                                     unsigned long paddr, int gaa,
 173                                     unsigned long vaddr, int asid, int dirty,
 174                                     int pagesize)
 175{
 176        tfh->fillasid = asid;
 177        tfh->fillvaddr = vaddr;
 178        tfh->pfn = paddr >> GRU_PADDR_SHIFT;
 179        tfh->gaa = gaa;
 180        tfh->dirty = dirty;
 181        tfh->pagesize = pagesize;
 182        tfh->opc = TFHOP_WRITE_RESTART;
 183        start_instruction(tfh);
 184}
 185
 186void tfh_user_polling_mode(struct gru_tlb_fault_handle *tfh)
 187{
 188        tfh->opc = TFHOP_USER_POLLING_MODE;
 189        start_instruction(tfh);
 190}
 191
 192void tfh_exception(struct gru_tlb_fault_handle *tfh)
 193{
 194        tfh->opc = TFHOP_EXCEPTION;
 195        start_instruction(tfh);
 196}
 197
 198