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tools/power turbostat: Fix missing SYS_LPI counter on some Chromebooks

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[ Upstream commit 1f81c5efc020314b2db30d77efe228b7e117750d ]

Some Chromebook BIOS' do not export an ACPI LPIT, which is how
Linux finds the residency counter for CPU and SYSTEM low power states,
that is exports in /sys/devices/system/cpu/cpuidle/*residency_us

When these sysfs attributes are missing, check the debugfs attrubte
from the pmc_core driver, which accesses the same counter value.

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Len Brown 2020-03-19 18:26:05 -04:00 committed by Greg Kroah-Hartman
parent 0ba0ce3cbb
commit 09116eeea6
1 changed files with 14 additions and 9 deletions
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23
tools/power/x86/turbostat/turbostat.c
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@ -304,6 +304,10 @@ int *irqs_per_cpu; /* indexed by cpu_num */
void setup_all_buffers(void);
char *sys_lpi_file;
char *sys_lpi_file_sysfs = "/sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us";
char *sys_lpi_file_debugfs = "/sys/kernel/debug/pmc_core/slp_s0_residency_usec";
int cpu_is_not_present(int cpu)
{
return !CPU_ISSET_S(cpu, cpu_present_setsize, cpu_present_set);
@ -2916,8 +2920,6 @@ int snapshot_gfx_mhz(void)
*
* record snapshot of
* /sys/devices/system/cpu/cpuidle/low_power_idle_cpu_residency_us
*
* return 1 if config change requires a restart, else return 0
*/
int snapshot_cpu_lpi_us(void)
{
@ -2941,17 +2943,14 @@ int snapshot_cpu_lpi_us(void)
/*
* snapshot_sys_lpi()
*
* record snapshot of
* /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us
*
* return 1 if config change requires a restart, else return 0
* record snapshot of sys_lpi_file
*/
int snapshot_sys_lpi_us(void)
{
FILE *fp;
int retval;
fp = fopen_or_die("/sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us", "r");
fp = fopen_or_die(sys_lpi_file, "r");
retval = fscanf(fp, "%lld", &cpuidle_cur_sys_lpi_us);
if (retval != 1) {
@ -4907,10 +4906,16 @@ void process_cpuid()
else
BIC_NOT_PRESENT(BIC_CPU_LPI);
if (!access("/sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us", R_OK))
if (!access(sys_lpi_file_sysfs, R_OK)) {
sys_lpi_file = sys_lpi_file_sysfs;
BIC_PRESENT(BIC_SYS_LPI);
else
} else if (!access(sys_lpi_file_debugfs, R_OK)) {
sys_lpi_file = sys_lpi_file_debugfs;
BIC_PRESENT(BIC_SYS_LPI);
} else {
sys_lpi_file_sysfs = NULL;
BIC_NOT_PRESENT(BIC_SYS_LPI);
}
if (!quiet)
decode_misc_feature_control();