Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3dd3ebe5 authored by Shilpasri G Bhat's avatar Shilpasri G Bhat Committed by Rafael J. Wysocki
Browse files

cpufreq: powernv: Report Psafe only if PMSR.psafe_mode_active bit is set 



On a reset cycle of OCC, although the system retires from safe
frequency state the local pstate is not restored to Pmin or last
requested pstate. Now if the cpufreq governor initiates a pstate
change, the local pstate will be in Psafe and we will be reporting a
false positive when we are not throttled.

So in powernv_cpufreq_throttle_check() remove the condition which
checks if local pstate is less than Pmin while checking for Psafe
frequency. If the cpus are forced to Psafe then PMSR.psafe_mode_active
bit will be set. So, when OCCs become active this bit will be cleared.
Let us just rely on this bit for reporting throttling.

Signed-off-by: default avatarShilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Reviewed-by: default avatarPreeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 735366fc

drivers/cpufreq/powernv-cpufreq.c

+3 −9
Original line number Diff line number Diff line
@@ -39,7 +39,6 @@ 
#define PMSR_PSAFE_ENABLE	(1UL << 30)

#define PMSR_SPR_EM_DISABLE	(1UL << 31)

#define PMSR_MAX(x)		((x >> 32) & 0xFF)

#define PMSR_LP(x)		((x >> 48) & 0xFF)



static struct cpufreq_frequency_table powernv_freqs[POWERNV_MAX_PSTATES+1];

static bool rebooting, throttled, occ_reset;
@@ -313,7 +312,7 @@ static void powernv_cpufreq_throttle_check(void *data) 
{

	unsigned int cpu = smp_processor_id();

	unsigned long pmsr;

	int pmsr_pmax, pmsr_lp, i;

	int pmsr_pmax, i;



	pmsr = get_pmspr(SPRN_PMSR);
@@ -335,14 +334,9 @@ static void powernv_cpufreq_throttle_check(void *data) 
			chips[i].id, pmsr_pmax);

	}



	/*

	 * Check for Psafe by reading LocalPstate

	 * or check if Psafe_mode_active is set in PMSR.

	 */

	/* Check if Psafe_mode_active is set in PMSR. */

next:

	pmsr_lp = (s8)PMSR_LP(pmsr);

	if ((pmsr_lp < powernv_pstate_info.min) ||

				(pmsr & PMSR_PSAFE_ENABLE)) {

	if (pmsr & PMSR_PSAFE_ENABLE) {

		throttled = true;

		pr_info("Pstate set to safe frequency\n");

	}