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 if (vmid < MAX_VMID) {
44 core_vmid->ptb_assigned_to_vmid[vmid] = ptb;
45 core_vmid->num_vmids_available--;
46 }
47 }
48
clear_entry_from_vmid_table(struct core_vmid * core_vmid,unsigned int vmid)49 static void clear_entry_from_vmid_table(struct core_vmid *core_vmid, unsigned int vmid)
50 {
51 if (vmid < MAX_VMID) {
52 core_vmid->ptb_assigned_to_vmid[vmid] = 0;
53 core_vmid->num_vmids_available++;
54 }
55 }
56
evict_vmids(struct core_vmid * core_vmid)57 static void evict_vmids(struct core_vmid *core_vmid)
58 {
59 int i;
60 int ord_int = dc_get_vmid_use_vector(core_vmid->dc);
61
62 ASSERT(ord_int >= 0 && ord_int <= 0xFFFF);
63 uint16_t ord = (uint16_t)ord_int;
64
65 // At this point any positions with value 0 are unused vmids, evict them
66 for (i = 1; i < core_vmid->num_vmid; i++) {
67 if (!(ord & (1u << i)))
68 clear_entry_from_vmid_table(core_vmid, i);
69 }
70 }
71
72 // Return value of -1 indicates vmid table uninitialized or ptb dne in the table
get_existing_vmid_for_ptb(struct core_vmid * core_vmid,uint64_t ptb)73 static int get_existing_vmid_for_ptb(struct core_vmid *core_vmid, uint64_t ptb)
74 {
75 int i;
76
77 for (i = 0; i < core_vmid->num_vmid; i++) {
78 if (core_vmid->ptb_assigned_to_vmid[i] == ptb)
79 return i;
80 }
81
82 return -1;
83 }
84
85 // Expected to be called only when there's an available vmid
get_next_available_vmid(struct core_vmid * core_vmid)86 static int get_next_available_vmid(struct core_vmid *core_vmid)
87 {
88 int i;
89
90 for (i = 1; i < core_vmid->num_vmid; i++) {
91 if (core_vmid->ptb_assigned_to_vmid[i] == 0)
92 return i;
93 }
94
95 return -1;
96 }
97
mod_vmid_get_for_ptb(struct mod_vmid * mod_vmid,uint64_t ptb)98 uint8_t mod_vmid_get_for_ptb(struct mod_vmid *mod_vmid, uint64_t ptb)
99 {
100 struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
101 int vmid = 0;
102
103 // Physical address gets vmid 0
104 if (ptb == 0)
105 return 0;
106
107 vmid = get_existing_vmid_for_ptb(core_vmid, ptb);
108
109 if (vmid == -1) {
110 struct dc_virtual_addr_space_config va_config = core_vmid->base_config;
111
112 va_config.page_table_base_addr = ptb;
113
114 if (core_vmid->num_vmids_available == 0)
115 evict_vmids(core_vmid);
116
117 vmid = get_next_available_vmid(core_vmid);
118 if (vmid != -1) {
119 add_ptb_to_table(core_vmid, vmid, ptb);
120
121 dc_setup_vm_context(core_vmid->dc, &va_config, vmid);
122 } else
123 ASSERT(0);
124 }
125
126 ASSERT(vmid >= 0 && vmid <= 0xFF);
127 return (uint8_t)vmid;
128 }
129
mod_vmid_reset(struct mod_vmid * mod_vmid)130 void mod_vmid_reset(struct mod_vmid *mod_vmid)
131 {
132 struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
133
134 core_vmid->num_vmids_available = core_vmid->num_vmid - 1;
135 memset(core_vmid->ptb_assigned_to_vmid, 0, sizeof(core_vmid->ptb_assigned_to_vmid[0]) * MAX_VMID);
136 }
137
mod_vmid_create(struct dc * dc,unsigned int num_vmid,struct dc_virtual_addr_space_config * va_config)138 struct mod_vmid *mod_vmid_create(
139 struct dc *dc,
140 unsigned int num_vmid,
141 struct dc_virtual_addr_space_config *va_config)
142 {
143 struct core_vmid *core_vmid;
144
145 if (num_vmid <= 1)
146 goto fail_no_vm_ctx;
147
148 if (dc == NULL)
149 goto fail_dc_null;
150
151 core_vmid = kzalloc_obj(struct core_vmid);
152
153 if (core_vmid == NULL)
154 goto fail_alloc_context;
155
156 core_vmid->dc = dc;
157 core_vmid->num_vmid = num_vmid;
158 core_vmid->num_vmids_available = num_vmid - 1;
159 core_vmid->base_config = *va_config;
160
161 memset(core_vmid->ptb_assigned_to_vmid, 0, sizeof(core_vmid->ptb_assigned_to_vmid[0]) * MAX_VMID);
162
163 return &core_vmid->public;
164
165 fail_no_vm_ctx:
166 fail_alloc_context:
167 fail_dc_null:
168 return NULL;
169 }
170
mod_vmid_destroy(struct mod_vmid * mod_vmid)171 void mod_vmid_destroy(struct mod_vmid *mod_vmid)
172 {
173 if (mod_vmid != NULL) {
174 struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
175
176 kfree(core_vmid);
177 }
178 }
179