blob: f91a047d082389f5323a662c69fa00f68795d9fb (
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
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2015 Intel Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <cpu/intel/speedstep.h>
#include <cpu/intel/turbo.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/tsc.h>
#include <soc/cpu.h>
#include <console/console.h>
#include <delay.h>
#include "chip.h"
unsigned long tsc_freq_mhz(void)
{
msr_t msr = rdmsr(MSR_PLATFORM_INFO);
return (BASE_CLOCK_MHZ * ((msr.lo >> 8) & 0xff));
}
void set_max_freq(void)
{
msr_t msr, msr_rd;
unsigned int eax;
eax = cpuid_eax(CPUID_LEAF_PM);
msr = rdmsr(MSR_IA32_MISC_ENABLES);
eax &= 0x2;
if ((!eax) && ((msr.hi & APL_BURST_MODE_DISABLE) == 0)) {
/* Burst Mode has been factory configured as disabled
* and is not available in this physical processor
* package.
*/
printk(BIOS_DEBUG, "Burst Mode is factory disabled\n");
return;
}
/* Enable burst mode */
msr.hi &= ~APL_BURST_MODE_DISABLE;
wrmsr(MSR_IA32_MISC_ENABLES, msr);
/* Enable speed step. */
msr = rdmsr(MSR_IA32_MISC_ENABLES);
msr.lo |= 1 << 16;
wrmsr(MSR_IA32_MISC_ENABLES, msr);
/* Set P-State ratio */
msr = rdmsr(IA32_PERF_CTL);
msr.lo &= ~0xff00;
/* Read the frequency limit ratio and set it properly in PERF_CTL */
msr_rd = rdmsr(FREQ_LIMIT_RATIO);
msr.lo |= (msr_rd.lo & 0xff) << 8;
wrmsr(IA32_PERF_CTL, msr);
}
|