linux-kernel - [PATCH 14/14] PM: domains: Trust domain-idle-states from DT to be correct by genpd

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Date:   Wed, 11 May 2022 16:57:04 +0200
From:   Ulf Hansson <ulf.hansson@...aro.org>
To:     "Rafael J . Wysocki" <rafael@...nel.org>, linux-pm@...r.kernel.org
Cc:     "Rafael J . Wysocki" <rjw@...ysocki.net>,
        Geert Uytterhoeven <geert+renesas@...der.be>,
        Maulik Shah <quic_mkshah@...cinc.com>,
        Gabriel Fernandez <gabriel.fernandez@...s.st.com>,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        Dmitry Osipenko <digetx@...il.com>,
        Kevin Hilman <khilman@...nel.org>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH 14/14] PM: domains: Trust domain-idle-states from DT to be correct by genpd

If genpd has parsed the domain-idle-states from DT, it's reasonable to
believe that the parsed data should be correct for the HW in question.
Based upon this, it seem superfluous to let genpd measure the corresponding
power-on/off latencies for these states.

Therefore, let's improve the behaviour in genpd by avoiding the
measurements for the domain-idle-states that have been parsed from DT.

Signed-off-by: Ulf Hansson <ulf.hansson@...aro.org>
---
 drivers/base/power/domain.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 83b073cdd0ed..739e52cd4aba 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -509,7 +509,7 @@ static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 	if (!genpd->power_on)
 		goto out;
 
-	timed = timed && genpd->gd;
+	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 	if (!timed) {
 		ret = genpd->power_on(genpd);
 		if (ret)
@@ -559,7 +559,7 @@ static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 	if (!genpd->power_off)
 		goto out;
 
-	timed = timed && genpd->gd;
+	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 	if (!timed) {
 		ret = genpd->power_off(genpd);
 		if (ret)
-- 
2.25.1