andrius
/
arm-trusted-firmware
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fix PSCI STAT time stamp collection 

This patch includes various fixes for PSCI STAT functionality
relating to timestamp collection:

1. The PSCI stat accounting for retention states for higher level
power domains were done outside the locks which could lead to
spurious values in some race conditions. This is moved inside
the locks. Also, the call to start the stat accounting was redundant
which is now removed.

2. The timestamp wrap-around case when calculating residency did
not cater for AArch32. This is now fixed.

3. In the warm boot path, `plat_psci_stat_accounting_stop()` was
getting invoked prior to population of target power states. This
is now corrected.

Change-Id: I851526455304fb74ff0a724f4d5318cd89e19589
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
This commit is contained in:
Soby Mathew 2017-10-16 15:19:31 +01:00
parent 122af7dd6d
commit bfc87a8dff
3 changed files with 15 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
lib/psci/psci_common.c
View File

@ -767,12 +767,12 @@ void psci_warmboot_entrypoint(void)
psci_acquire_pwr_domain_locks(end_pwrlvl,
cpu_idx);
psci_get_target_local_pwr_states(end_pwrlvl, &state_info);
#if ENABLE_PSCI_STAT
plat_psci_stat_accounting_stop(&state_info);
#endif
psci_get_target_local_pwr_states(end_pwrlvl, &state_info);
/*
* This CPU could be resuming from suspend or it could have just been
* turned on. To distinguish between these 2 cases, we examine the

14
lib/psci/psci_suspend.c
View File

@ -37,6 +37,11 @@ static void psci_suspend_to_standby_finisher(unsigned int cpu_idx,
*/
psci_get_target_local_pwr_states(end_pwrlvl, &state_info);
#if ENABLE_PSCI_STAT
plat_psci_stat_accounting_stop(&state_info);
psci_stats_update_pwr_up(end_pwrlvl, &state_info);
#endif
/*
* Plat. management: Allow the platform to do operations
* on waking up from retention.
@ -236,10 +241,6 @@ exit:
PMF_NO_CACHE_MAINT);
#endif
#if ENABLE_PSCI_STAT
plat_psci_stat_accounting_start(state_info);
#endif
/*
* We will reach here if only retention/standby states have been
* requested at multiple power levels. This means that the cpu
@ -247,11 +248,6 @@ exit:
*/
wfi();
#if ENABLE_PSCI_STAT
plat_psci_stat_accounting_stop(state_info);
psci_stats_update_pwr_up(end_pwrlvl, state_info);
#endif
#if ENABLE_RUNTIME_INSTRUMENTATION
PMF_CAPTURE_TIMESTAMP(rt_instr_svc,
RT_INSTR_EXIT_HW_LOW_PWR,

9
plat/common/plat_psci_common.c
View File

@ -18,6 +18,13 @@
/* Ticks elapsed in one second by a signal of 1 MHz */
#define MHZ_TICKS_PER_SEC 1000000
/* Maximum time-stamp value read from architectural counters */
#ifdef AARCH32
#define MAX_TS UINT32_MAX
#else
#define MAX_TS UINT64_MAX
#endif
/* Following are used as ID's to capture time-stamp */
#define PSCI_STAT_ID_ENTER_LOW_PWR 0
#define PSCI_STAT_ID_EXIT_LOW_PWR 1
@ -45,7 +52,7 @@ static u_register_t calc_stat_residency(unsigned long long pwrupts,
assert(residency_div);
if (pwrupts < pwrdnts)
res = UINT64_MAX - pwrdnts + pwrupts;
res = MAX_TS - pwrdnts + pwrupts;
else
res = pwrupts - pwrdnts;