1 /*
2  * Copyright (c) 2023, Google, Inc. All rights reserved
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining
5  * a copy of this software and associated documentation files
6  * (the "Software"), to deal in the Software without restriction,
7  * including without limitation the rights to use, copy, modify, merge,
8  * publish, distribute, sublicense, and/or sell copies of the Software,
9  * and to permit persons to whom the Software is furnished to do so,
10  * subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be
13  * included in all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <arch/arm64/sregs.h>
25 #include <arch/arm64.h>
26 #include <arch/ops.h>
27 #include <inttypes.h>
28 #include <stdbool.h>
29 
arch_sve_supported(void)30 bool arch_sve_supported(void) {
31     uint64_t v = ARM64_READ_SYSREG(id_aa64pfr0_el1);
32     return ((v >> ID_AA64PFR0_EL1_SVE_SHIFT) & ID_AA64PFR0_EL1_SVE_MASK) ==
33            ID_AA64PFR0_EL1_SVE_SUPPORTED;
34 }
35 
arch_disable_sve(void)36 uint64_t arch_disable_sve(void) {
37     uint64_t v = ARM64_READ_SYSREG(cpacr_el1);
38     uint64_t v_tmp = v & (CPACR_EL1_ZEN_SVE_DISABLE << CPACR_EL1_ZEN_SHIFT);
39     v_tmp = v_tmp & (CPACR_EL1_FPEN_SVE_DISABLE << CPACR_EL1_FPEN_SHIFT);
40 
41     ARM64_WRITE_SYSREG(cpacr_el1, v_tmp);
42 
43     return v;
44 }
45 
arch_enable_sve(void)46 uint64_t arch_enable_sve(void) {
47     uint64_t v = ARM64_READ_SYSREG(cpacr_el1);
48 
49     arch_disable_sve();
50     uint64_t v_tmp = v | (CPACR_EL1_ZEN_SVE_ENABLE << CPACR_EL1_ZEN_SHIFT);
51     v_tmp = v_tmp | (CPACR_EL1_FPEN_SVE_ENABLE << CPACR_EL1_FPEN_SHIFT);
52 
53     ARM64_WRITE_SYSREG(cpacr_el1, v_tmp);
54 
55     return v;
56 }
57 
58