misc/sgi-gru/gruhandles.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  *              GRU KERNEL MCS INSTRUCTIONS
0004  *
0005  *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
0006  */
0007
0008 #include <linux/kernel.h>
0009 #include "gru.h"
0010 #include "grulib.h"
0011 #include "grutables.h"
0012
0013 /* 10 sec */
0014 #ifdef CONFIG_IA64
0015 #include <asm/processor.h>
0016 #define GRU_OPERATION_TIMEOUT   (((cycles_t) local_cpu_data->itc_freq)*10)
0017 #define CLKS2NSEC(c)        ((c) *1000000000 / local_cpu_data->itc_freq)
0018 #else
0019 #include <linux/sync_core.h>
0020 #include <asm/tsc.h>
0021 #define GRU_OPERATION_TIMEOUT   ((cycles_t) tsc_khz*10*1000)
0022 #define CLKS2NSEC(c)        ((c) * 1000000 / tsc_khz)
0023 #endif
0024
0025 /* Extract the status field from a kernel handle */
0026 #define GET_MSEG_HANDLE_STATUS(h)   (((*(unsigned long *)(h)) >> 16) & 3)
0027
0028 struct mcs_op_statistic mcs_op_statistics[mcsop_last];
0029
0030 static void update_mcs_stats(enum mcs_op op, unsigned long clks)
0031 {
0032     unsigned long nsec;
0033
0034     nsec = CLKS2NSEC(clks);
0035     atomic_long_inc(&mcs_op_statistics[op].count);
0036     atomic_long_add(nsec, &mcs_op_statistics[op].total);
0037     if (mcs_op_statistics[op].max < nsec)
0038         mcs_op_statistics[op].max = nsec;
0039 }
0040
0041 static void start_instruction(void *h)
0042 {
0043     unsigned long *w0 = h;
0044
0045     wmb();      /* setting CMD/STATUS bits must be last */
0046     *w0 = *w0 | 0x20001;
0047     gru_flush_cache(h);
0048 }
0049
0050 static void report_instruction_timeout(void *h)
0051 {
0052     unsigned long goff = GSEGPOFF((unsigned long)h);
0053     char *id = "???";
0054
0055     if (TYPE_IS(CCH, goff))
0056         id = "CCH";
0057     else if (TYPE_IS(TGH, goff))
0058         id = "TGH";
0059     else if (TYPE_IS(TFH, goff))
0060         id = "TFH";
0061
0062     panic(KERN_ALERT "GRU %p (%s) is malfunctioning\n", h, id);
0063 }
0064
0065 static int wait_instruction_complete(void *h, enum mcs_op opc)
0066 {
0067     int status;
0068     unsigned long start_time = get_cycles();
0069
0070     while (1) {
0071         cpu_relax();
0072         status = GET_MSEG_HANDLE_STATUS(h);
0073         if (status != CCHSTATUS_ACTIVE)
0074             break;
0075         if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time)) {
0076             report_instruction_timeout(h);
0077             start_time = get_cycles();
0078         }
0079     }
0080     if (gru_options & OPT_STATS)
0081         update_mcs_stats(opc, get_cycles() - start_time);
0082     return status;
0083 }
0084
0085 int cch_allocate(struct gru_context_configuration_handle *cch)
0086 {
0087     int ret;
0088
0089     cch->opc = CCHOP_ALLOCATE;
0090     start_instruction(cch);
0091     ret = wait_instruction_complete(cch, cchop_allocate);
0092
0093     /*
0094      * Stop speculation into the GSEG being mapped by the previous ALLOCATE.
0095      * The GSEG memory does not exist until the ALLOCATE completes.
0096      */
0097     sync_core();
0098     return ret;
0099 }
0100
0101 int cch_start(struct gru_context_configuration_handle *cch)
0102 {
0103     cch->opc = CCHOP_START;
0104     start_instruction(cch);
0105     return wait_instruction_complete(cch, cchop_start);
0106 }
0107
0108 int cch_interrupt(struct gru_context_configuration_handle *cch)
0109 {
0110     cch->opc = CCHOP_INTERRUPT;
0111     start_instruction(cch);
0112     return wait_instruction_complete(cch, cchop_interrupt);
0113 }
0114
0115 int cch_deallocate(struct gru_context_configuration_handle *cch)
0116 {
0117     int ret;
0118
0119     cch->opc = CCHOP_DEALLOCATE;
0120     start_instruction(cch);
0121     ret = wait_instruction_complete(cch, cchop_deallocate);
0122
0123     /*
0124      * Stop speculation into the GSEG being unmapped by the previous
0125      * DEALLOCATE.
0126      */
0127     sync_core();
0128     return ret;
0129 }
0130
0131 int cch_interrupt_sync(struct gru_context_configuration_handle
0132                      *cch)
0133 {
0134     cch->opc = CCHOP_INTERRUPT_SYNC;
0135     start_instruction(cch);
0136     return wait_instruction_complete(cch, cchop_interrupt_sync);
0137 }
0138
0139 int tgh_invalidate(struct gru_tlb_global_handle *tgh,
0140                  unsigned long vaddr, unsigned long vaddrmask,
0141                  int asid, int pagesize, int global, int n,
0142                  unsigned short ctxbitmap)
0143 {
0144     tgh->vaddr = vaddr;
0145     tgh->asid = asid;
0146     tgh->pagesize = pagesize;
0147     tgh->n = n;
0148     tgh->global = global;
0149     tgh->vaddrmask = vaddrmask;
0150     tgh->ctxbitmap = ctxbitmap;
0151     tgh->opc = TGHOP_TLBINV;
0152     start_instruction(tgh);
0153     return wait_instruction_complete(tgh, tghop_invalidate);
0154 }
0155
0156 int tfh_write_only(struct gru_tlb_fault_handle *tfh,
0157                   unsigned long paddr, int gaa,
0158                   unsigned long vaddr, int asid, int dirty,
0159                   int pagesize)
0160 {
0161     tfh->fillasid = asid;
0162     tfh->fillvaddr = vaddr;
0163     tfh->pfn = paddr >> GRU_PADDR_SHIFT;
0164     tfh->gaa = gaa;
0165     tfh->dirty = dirty;
0166     tfh->pagesize = pagesize;
0167     tfh->opc = TFHOP_WRITE_ONLY;
0168     start_instruction(tfh);
0169     return wait_instruction_complete(tfh, tfhop_write_only);
0170 }
0171
0172 void tfh_write_restart(struct gru_tlb_fault_handle *tfh,
0173                      unsigned long paddr, int gaa,
0174                      unsigned long vaddr, int asid, int dirty,
0175                      int pagesize)
0176 {
0177     tfh->fillasid = asid;
0178     tfh->fillvaddr = vaddr;
0179     tfh->pfn = paddr >> GRU_PADDR_SHIFT;
0180     tfh->gaa = gaa;
0181     tfh->dirty = dirty;
0182     tfh->pagesize = pagesize;
0183     tfh->opc = TFHOP_WRITE_RESTART;
0184     start_instruction(tfh);
0185 }
0186
0187 void tfh_user_polling_mode(struct gru_tlb_fault_handle *tfh)
0188 {
0189     tfh->opc = TFHOP_USER_POLLING_MODE;
0190     start_instruction(tfh);
0191 }
0192
0193 void tfh_exception(struct gru_tlb_fault_handle *tfh)
0194 {
0195     tfh->opc = TFHOP_EXCEPTION;
0196     start_instruction(tfh);
0197 }
0198