From: Len Brown <len.brown@xxxxxxxxx>
[ 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@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/power/x86/turbostat/turbostat.c | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index fb665fdc722a4..2233cf722c692 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -299,6 +299,10 @@ 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);
@@ -2844,8 +2848,6 @@ 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)
{
@@ -2865,17 +2867,14 @@ 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)
@@ -4743,10 +4742,16 @@ 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();
--
2.20.1
