f1117a7637a21465e338a87f4971946ca836e6cc
[linux-2.6.git] / 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 #else
31 #include <asm/tsc.h>
32 #define GRU_OPERATION_TIMEOUT   ((cycles_t) tsc_khz*10*1000)
33 #endif
34
35 /* Extract the status field from a kernel handle */
36 #define GET_MSEG_HANDLE_STATUS(h)       (((*(unsigned long *)(h)) >> 16) & 3)
37
38 struct mcs_op_statistic mcs_op_statistics[mcsop_last];
39
40 static void update_mcs_stats(enum mcs_op op, unsigned long clks)
41 {
42         atomic_long_inc(&mcs_op_statistics[op].count);
43         atomic_long_add(clks, &mcs_op_statistics[op].total);
44         if (mcs_op_statistics[op].max < clks)
45                 mcs_op_statistics[op].max = clks;
46 }
47
48 static void start_instruction(void *h)
49 {
50         unsigned long *w0 = h;
51
52         wmb();          /* setting CMD bit must be last */
53         *w0 = *w0 | 1;
54         gru_flush_cache(h);
55 }
56
57 static void report_instruction_timeout(void *h)
58 {
59         unsigned long goff = GSEGPOFF((unsigned long)h);
60         char *id = "???";
61
62         if (TYPE_IS(CCH, goff))
63                 id = "CCH";
64         else if (TYPE_IS(TGH, goff))
65                 id = "TGH";
66         else if (TYPE_IS(TFH, goff))
67                 id = "TFH";
68
69         panic(KERN_ALERT "GRU %p (%s) is malfunctioning\n", h, id);
70 }
71
72 static int wait_instruction_complete(void *h, enum mcs_op opc)
73 {
74         int status;
75         unsigned long start_time = get_cycles();
76
77         while (1) {
78                 cpu_relax();
79                 status = GET_MSEG_HANDLE_STATUS(h);
80                 if (status != CCHSTATUS_ACTIVE)
81                         break;
82                 if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time)) {
83                         report_instruction_timeout(h);
84                         start_time = get_cycles();
85                 }
86         }
87         if (gru_options & OPT_STATS)
88                 update_mcs_stats(opc, get_cycles() - start_time);
89         return status;
90 }
91
92 int cch_allocate(struct gru_context_configuration_handle *cch)
93 {
94         int ret;
95
96         cch->opc = CCHOP_ALLOCATE;
97         start_instruction(cch);
98         ret = wait_instruction_complete(cch, cchop_allocate);
99
100         /*
101          * Stop speculation into the GSEG being mapped by the previous ALLOCATE.
102          * The GSEG memory does not exist until the ALLOCATE completes.
103          */
104         sync_core();
105         return ret;
106 }
107
108 int cch_start(struct gru_context_configuration_handle *cch)
109 {
110         cch->opc = CCHOP_START;
111         start_instruction(cch);
112         return wait_instruction_complete(cch, cchop_start);
113 }
114
115 int cch_interrupt(struct gru_context_configuration_handle *cch)
116 {
117         cch->opc = CCHOP_INTERRUPT;
118         start_instruction(cch);
119         return wait_instruction_complete(cch, cchop_interrupt);
120 }
121
122 int cch_deallocate(struct gru_context_configuration_handle *cch)
123 {
124         int ret;
125
126         cch->opc = CCHOP_DEALLOCATE;
127         start_instruction(cch);
128         ret = wait_instruction_complete(cch, cchop_deallocate);
129
130         /*
131          * Stop speculation into the GSEG being unmapped by the previous
132          * DEALLOCATE.
133          */
134         sync_core();
135         return ret;
136 }
137
138 int cch_interrupt_sync(struct gru_context_configuration_handle
139                                      *cch)
140 {
141         cch->opc = CCHOP_INTERRUPT_SYNC;
142         start_instruction(cch);
143         return wait_instruction_complete(cch, cchop_interrupt_sync);
144 }
145
146 int tgh_invalidate(struct gru_tlb_global_handle *tgh,
147                                  unsigned long vaddr, unsigned long vaddrmask,
148                                  int asid, int pagesize, int global, int n,
149                                  unsigned short ctxbitmap)
150 {
151         tgh->vaddr = vaddr;
152         tgh->asid = asid;
153         tgh->pagesize = pagesize;
154         tgh->n = n;
155         tgh->global = global;
156         tgh->vaddrmask = vaddrmask;
157         tgh->ctxbitmap = ctxbitmap;
158         tgh->opc = TGHOP_TLBINV;
159         start_instruction(tgh);
160         return wait_instruction_complete(tgh, tghop_invalidate);
161 }
162
163 void tfh_write_only(struct gru_tlb_fault_handle *tfh,
164                                   unsigned long pfn, unsigned long vaddr,
165                                   int asid, int dirty, int pagesize)
166 {
167         tfh->fillasid = asid;
168         tfh->fillvaddr = vaddr;
169         tfh->pfn = pfn;
170         tfh->dirty = dirty;
171         tfh->pagesize = pagesize;
172         tfh->opc = TFHOP_WRITE_ONLY;
173         start_instruction(tfh);
174 }
175
176 void tfh_write_restart(struct gru_tlb_fault_handle *tfh,
177                                      unsigned long paddr, int gaa,
178                                      unsigned long vaddr, int asid, int dirty,
179                                      int pagesize)
180 {
181         tfh->fillasid = asid;
182         tfh->fillvaddr = vaddr;
183         tfh->pfn = paddr >> GRU_PADDR_SHIFT;
184         tfh->gaa = gaa;
185         tfh->dirty = dirty;
186         tfh->pagesize = pagesize;
187         tfh->opc = TFHOP_WRITE_RESTART;
188         start_instruction(tfh);
189 }
190
191 void tfh_restart(struct gru_tlb_fault_handle *tfh)
192 {
193         tfh->opc = TFHOP_RESTART;
194         start_instruction(tfh);
195 }
196
197 void tfh_user_polling_mode(struct gru_tlb_fault_handle *tfh)
198 {
199         tfh->opc = TFHOP_USER_POLLING_MODE;
200         start_instruction(tfh);
201 }
202
203 void tfh_exception(struct gru_tlb_fault_handle *tfh)
204 {
205         tfh->opc = TFHOP_EXCEPTION;
206         start_instruction(tfh);
207 }
208