blob: 08d823d72586e815533bc6e027cec6e8ddd8b10c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* cppc.c: CPPC Interface for x86
* Copyright (c) 2016, Intel Corporation.
*/
#include <acpi/cppc_acpi.h>
#include <asm/msr.h>
/* Refer to drivers/acpi/cppc_acpi.c for the description of functions */
bool cpc_ffh_supported(void)
{
return true;
}
int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val)
{
int err;
err = rdmsrl_safe_on_cpu(cpunum, reg->address, val);
if (!err) {
u64 mask = GENMASK_ULL(reg->bit_offset + reg->bit_width - 1,
reg->bit_offset);
*val &= mask;
*val >>= reg->bit_offset;
}
return err;
}
int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val)
{
u64 rd_val;
int err;
err = rdmsrl_safe_on_cpu(cpunum, reg->address, &rd_val);
if (!err) {
u64 mask = GENMASK_ULL(reg->bit_offset + reg->bit_width - 1,
reg->bit_offset);
val <<= reg->bit_offset;
val &= mask;
rd_val &= ~mask;
rd_val |= val;
err = wrmsrl_safe_on_cpu(cpunum, reg->address, rd_val);
}
return err;
}
|
