1 /*
2 * Copyright 2019 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: AMD
23 *
24 */
25
26 #include "mod_vmid.h"
27
28 struct core_vmid {
29 struct mod_vmid public;
30 struct dc *dc;
31
32 unsigned int num_vmid;
33 unsigned int num_vmids_available;
34 uint64_t ptb_assigned_to_vmid[MAX_VMID];
35 struct dc_virtual_addr_space_config base_config;
36 };
37
38 #define MOD_VMID_TO_CORE(mod_vmid)\
39 container_of(mod_vmid, struct core_vmid, public)
40
add_ptb_to_table(struct core_vmid * core_vmid,unsigned int vmid,uint64_t ptb)41 static void add_ptb_to_table(struct core_vmid *core_vmid, unsigned int vmid, uint64_t ptb)
42 {
43 core_vmid->ptb_assigned_to_vmid[vmid] = ptb;
44 core_vmid->num_vmids_available--;
45 }
46
clear_entry_from_vmid_table(struct core_vmid * core_vmid,unsigned int vmid)47 static void clear_entry_from_vmid_table(struct core_vmid *core_vmid, unsigned int vmid)
48 {
49 core_vmid->ptb_assigned_to_vmid[vmid] = 0;
50 core_vmid->num_vmids_available++;
51 }
52
evict_vmids(struct core_vmid * core_vmid)53 static void evict_vmids(struct core_vmid *core_vmid)
54 {
55 int i;
56 uint16_t ord = dc_get_vmid_use_vector(core_vmid->dc);
57
58 // At this point any positions with value 0 are unused vmids, evict them
59 for (i = 1; i < core_vmid->num_vmid; i++) {
60 if (ord & (1u << i))
61 clear_entry_from_vmid_table(core_vmid, i);
62 }
63 }
64
65 // Return value of -1 indicates vmid table unitialized or ptb dne in the table
get_existing_vmid_for_ptb(struct core_vmid * core_vmid,uint64_t ptb)66 static int get_existing_vmid_for_ptb(struct core_vmid *core_vmid, uint64_t ptb)
67 {
68 int i;
69
70 for (i = 0; i < core_vmid->num_vmid; i++) {
71 if (core_vmid->ptb_assigned_to_vmid[i] == ptb)
72 return i;
73 }
74
75 return -1;
76 }
77
78 // Expected to be called only when there's an available vmid
get_next_available_vmid(struct core_vmid * core_vmid)79 static int get_next_available_vmid(struct core_vmid *core_vmid)
80 {
81 int i;
82
83 for (i = 1; i < core_vmid->num_vmid; i++) {
84 if (core_vmid->ptb_assigned_to_vmid[i] == 0)
85 return i;
86 }
87
88 return -1;
89 }
90
mod_vmid_get_for_ptb(struct mod_vmid * mod_vmid,uint64_t ptb)91 uint8_t mod_vmid_get_for_ptb(struct mod_vmid *mod_vmid, uint64_t ptb)
92 {
93 struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
94 unsigned int vmid = 0;
95
96 // Physical address gets vmid 0
97 if (ptb == 0)
98 return 0;
99
100 vmid = get_existing_vmid_for_ptb(core_vmid, ptb);
101
102 if (vmid == -1) {
103 struct dc_virtual_addr_space_config va_config = core_vmid->base_config;
104
105 va_config.page_table_base_addr = ptb;
106
107 if (core_vmid->num_vmids_available == 0)
108 evict_vmids(core_vmid);
109
110 vmid = get_next_available_vmid(core_vmid);
111 add_ptb_to_table(core_vmid, vmid, ptb);
112
113 dc_setup_vm_context(core_vmid->dc, &va_config, vmid);
114 }
115
116 return vmid;
117 }
118
mod_vmid_reset(struct mod_vmid * mod_vmid)119 void mod_vmid_reset(struct mod_vmid *mod_vmid)
120 {
121 struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
122
123 core_vmid->num_vmids_available = core_vmid->num_vmid - 1;
124 memset(core_vmid->ptb_assigned_to_vmid, 0, sizeof(core_vmid->ptb_assigned_to_vmid[0]) * MAX_VMID);
125 }
126
mod_vmid_create(struct dc * dc,unsigned int num_vmid,struct dc_virtual_addr_space_config * va_config)127 struct mod_vmid *mod_vmid_create(
128 struct dc *dc,
129 unsigned int num_vmid,
130 struct dc_virtual_addr_space_config *va_config)
131 {
132 struct core_vmid *core_vmid;
133
134 if (num_vmid <= 1)
135 goto fail_no_vm_ctx;
136
137 if (dc == NULL)
138 goto fail_dc_null;
139
140 core_vmid = kzalloc(sizeof(struct core_vmid), GFP_KERNEL);
141
142 if (core_vmid == NULL)
143 goto fail_alloc_context;
144
145 core_vmid->dc = dc;
146 core_vmid->num_vmid = num_vmid;
147 core_vmid->num_vmids_available = num_vmid - 1;
148 core_vmid->base_config = *va_config;
149
150 memset(core_vmid->ptb_assigned_to_vmid, 0, sizeof(core_vmid->ptb_assigned_to_vmid[0]) * MAX_VMID);
151
152 return &core_vmid->public;
153
154 fail_no_vm_ctx:
155 fail_alloc_context:
156 fail_dc_null:
157 return NULL;
158 }
159
mod_vmid_destroy(struct mod_vmid * mod_vmid)160 void mod_vmid_destroy(struct mod_vmid *mod_vmid)
161 {
162 if (mod_vmid != NULL) {
163 struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
164
165 kfree(core_vmid);
166 }
167 }
168