coreboot-kgpe-d16/src/soc/intel/braswell/tsc_freq.c
Angel Pons ba38f37d18 soc/intel/braswell: Use SPDX for GPL-2.0-only files
Done with sed and God Lines. Only done for C-like code for now.

Change-Id: I45d746ed374361036d59167293a90d8e557754fa
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40210
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by:  Felix Singer <felixsinger@posteo.net>
2020-04-06 19:15:37 +00:00

68 lines
1.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/* This file is part of the coreboot project. */
#include <cpu/x86/msr.h>
#include <cpu/x86/tsc.h>
#include <soc/msr.h>
#include <stdint.h>
static const unsigned int cpu_bus_clk_freq_table[] = {
83333,
100000,
133333,
116666,
80000,
93333,
90000,
88900,
87500
};
unsigned int cpu_bus_freq_khz(void)
{
msr_t clk_info = rdmsr(MSR_BSEL_CR_OVERCLOCK_CONTROL);
if ((clk_info.lo & 0xf) < (sizeof(cpu_bus_clk_freq_table) / sizeof(unsigned int)))
return cpu_bus_clk_freq_table[clk_info.lo & 0xf];
return 0;
}
unsigned long tsc_freq_mhz(void)
{
msr_t platform_info;
unsigned int bclk_khz = cpu_bus_freq_khz();
if (!bclk_khz)
return 0;
platform_info = rdmsr(MSR_PLATFORM_INFO);
return (bclk_khz * ((platform_info.lo >> 8) & 0xff)) / 1000;
}
void set_max_freq(void)
{
msr_t perf_ctl;
msr_t msr;
/* Enable Intel SpeedStep */
msr = rdmsr(IA32_MISC_ENABLE);
msr.lo |= (1 << 16);
wrmsr(IA32_MISC_ENABLE, msr);
/* Enable Burst Mode */
msr = rdmsr(IA32_MISC_ENABLE);
msr.hi = 0;
wrmsr(IA32_MISC_ENABLE, msr);
/* Set guaranteed ratio [21:16] from IACORE_RATIOS to bits [15:8] of the PERF_CTL */
msr = rdmsr(MSR_IACORE_TURBO_RATIOS);
perf_ctl.lo = (msr.lo & 0x003f0000) >> 8;
/* Set guaranteed vid [21:16] from IACORE_VIDS to bits [7:0] of the PERF_CTL */
msr = rdmsr(MSR_IACORE_TURBO_VIDS);
perf_ctl.lo |= (msr.lo & 0x007f0000) >> 16;
perf_ctl.hi = 0;
wrmsr(IA32_PERF_CTL, perf_ctl);
}