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 int wait_instruction_complete(void *h, enum mcs_op opc)
58 {
59 	int status;
60 	unsigned long start_time = get_cycles();
61 
62 	while (1) {
63 		cpu_relax();
64 		status = GET_MSEG_HANDLE_STATUS(h);
65 		if (status != CCHSTATUS_ACTIVE)
66 			break;
67 		if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time))
68 			panic("GRU %p is malfunctioning: start %ld, end %ld\n",
69 			      h, start_time, (unsigned long)get_cycles());
70 	}
71 	if (gru_options & OPT_STATS)
72 		update_mcs_stats(opc, get_cycles() - start_time);
73 	return status;
74 }
75 
76 int cch_allocate(struct gru_context_configuration_handle *cch)
77 {
78 	cch->opc = CCHOP_ALLOCATE;
79 	start_instruction(cch);
80 	return wait_instruction_complete(cch, cchop_allocate);
81 }
82 
83 int cch_start(struct gru_context_configuration_handle *cch)
84 {
85 	cch->opc = CCHOP_START;
86 	start_instruction(cch);
87 	return wait_instruction_complete(cch, cchop_start);
88 }
89 
90 int cch_interrupt(struct gru_context_configuration_handle *cch)
91 {
92 	cch->opc = CCHOP_INTERRUPT;
93 	start_instruction(cch);
94 	return wait_instruction_complete(cch, cchop_interrupt);
95 }
96 
97 int cch_deallocate(struct gru_context_configuration_handle *cch)
98 {
99 	cch->opc = CCHOP_DEALLOCATE;
100 	start_instruction(cch);
101 	return wait_instruction_complete(cch, cchop_deallocate);
102 }
103 
104 int cch_interrupt_sync(struct gru_context_configuration_handle
105 				     *cch)
106 {
107 	cch->opc = CCHOP_INTERRUPT_SYNC;
108 	start_instruction(cch);
109 	return wait_instruction_complete(cch, cchop_interrupt_sync);
110 }
111 
112 int tgh_invalidate(struct gru_tlb_global_handle *tgh,
113 				 unsigned long vaddr, unsigned long vaddrmask,
114 				 int asid, int pagesize, int global, int n,
115 				 unsigned short ctxbitmap)
116 {
117 	tgh->vaddr = vaddr;
118 	tgh->asid = asid;
119 	tgh->pagesize = pagesize;
120 	tgh->n = n;
121 	tgh->global = global;
122 	tgh->vaddrmask = vaddrmask;
123 	tgh->ctxbitmap = ctxbitmap;
124 	tgh->opc = TGHOP_TLBINV;
125 	start_instruction(tgh);
126 	return wait_instruction_complete(tgh, tghop_invalidate);
127 }
128 
129 void tfh_write_only(struct gru_tlb_fault_handle *tfh,
130 				  unsigned long pfn, unsigned long vaddr,
131 				  int asid, int dirty, int pagesize)
132 {
133 	tfh->fillasid = asid;
134 	tfh->fillvaddr = vaddr;
135 	tfh->pfn = pfn;
136 	tfh->dirty = dirty;
137 	tfh->pagesize = pagesize;
138 	tfh->opc = TFHOP_WRITE_ONLY;
139 	start_instruction(tfh);
140 }
141 
142 void tfh_write_restart(struct gru_tlb_fault_handle *tfh,
143 				     unsigned long paddr, int gaa,
144 				     unsigned long vaddr, int asid, int dirty,
145 				     int pagesize)
146 {
147 	tfh->fillasid = asid;
148 	tfh->fillvaddr = vaddr;
149 	tfh->pfn = paddr >> GRU_PADDR_SHIFT;
150 	tfh->gaa = gaa;
151 	tfh->dirty = dirty;
152 	tfh->pagesize = pagesize;
153 	tfh->opc = TFHOP_WRITE_RESTART;
154 	start_instruction(tfh);
155 }
156 
157 void tfh_restart(struct gru_tlb_fault_handle *tfh)
158 {
159 	tfh->opc = TFHOP_RESTART;
160 	start_instruction(tfh);
161 }
162 
163 void tfh_user_polling_mode(struct gru_tlb_fault_handle *tfh)
164 {
165 	tfh->opc = TFHOP_USER_POLLING_MODE;
166 	start_instruction(tfh);
167 }
168 
169 void tfh_exception(struct gru_tlb_fault_handle *tfh)
170 {
171 	tfh->opc = TFHOP_EXCEPTION;
172 	start_instruction(tfh);
173 }
174 
175