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From: Rajendra Nayak <rnayak@codeaurora.org>
To: ulf.hansson@linaro.org, bjorn.andersson@linaro.org,
	viresh.kumar@linaro.org
Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	swboyd@chromium.org, rojay@codeaurora.org, stephan@gerhold.net,
	Rajendra Nayak <rnayak@codeaurora.org>
Subject: [PATCH v5 1/2] PM / Domains: Add support for 'required-opps' to set default perf state
Date: Tue, 20 Jul 2021 12:37:55 +0530	[thread overview]
Message-ID: <1626764876-10229-2-git-send-email-rnayak@codeaurora.org> (raw)
In-Reply-To: <1626764876-10229-1-git-send-email-rnayak@codeaurora.org>

Some devices within power domains with performance states do not
support DVFS, but still need to vote on a default/static state
while they are active. They can express this using the 'required-opps'
property in device tree, which points to the phandle of the OPP
supported by the corresponding power-domains.

Add support to parse this information from DT and then set the
specified performance state during attach and drop it on detach.
runtime suspend/resume callbacks already have logic to drop/set
the vote as needed and should take care of dropping the default
perf state vote on runtime suspend and restore it back on runtime
resume.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
---
 drivers/base/power/domain.c | 28 +++++++++++++++++++++++++---
 include/linux/pm_domain.h   |  1 +
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index a934c67..f454031 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2598,6 +2598,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
 
 	dev_dbg(dev, "removing from PM domain %s\n", pd->name);
 
+	/* Drop the default performance state */
+	if (dev_gpd_data(dev)->default_pstate) {
+		dev_pm_genpd_set_performance_state(dev, 0);
+		dev_gpd_data(dev)->default_pstate = 0;
+	}
+
 	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
 		ret = genpd_remove_device(pd, dev);
 		if (ret != -EAGAIN)
@@ -2635,9 +2641,10 @@ static void genpd_dev_pm_sync(struct device *dev)
 static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
 				 unsigned int index, bool power_on)
 {
+	struct device_node *np;
 	struct of_phandle_args pd_args;
 	struct generic_pm_domain *pd;
-	int ret;
+	int ret, pstate;
 
 	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
 				"#power-domain-cells", index, &pd_args);
@@ -2675,10 +2682,25 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
 		genpd_unlock(pd);
 	}
 
-	if (ret)
+	if (ret) {
 		genpd_remove_device(pd, dev);
+		return -EPROBE_DEFER;
+	}
+
+	/* Set the default performance state */
+	np = base_dev->of_node;
+	if (of_parse_phandle(np, "required-opps", index)) {
+		pstate = of_get_required_opp_performance_state(np, index);
+		if (pstate < 0) {
+			ret = pstate;
+			dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
+				pd->name, ret);
+		}
+		dev_pm_genpd_set_performance_state(dev, pstate);
+		dev_gpd_data(dev)->default_pstate = pstate;
+	}
 
-	return ret ? -EPROBE_DEFER : 1;
+	return ret ? ret : 1;
 }
 
 /**
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 21a0577..67017c9 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -198,6 +198,7 @@ struct generic_pm_domain_data {
 	struct notifier_block *power_nb;
 	int cpu;
 	unsigned int performance_state;
+	unsigned int default_pstate;
 	unsigned int rpm_pstate;
 	ktime_t	next_wakeup;
 	void *data;
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation


  reply	other threads:[~2021-07-20  7:12 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-20  7:07 [PATCH v5 0/2] " Rajendra Nayak
2021-07-20  7:07 ` Rajendra Nayak [this message]
2021-07-20  7:18   ` [PATCH v5 1/2] " Felipe Balbi
2021-08-02 12:59   ` Ulf Hansson
2021-08-03  4:38     ` Rajendra Nayak
2021-08-04 11:08       ` Rajendra Nayak
2021-08-04 11:39         ` Ulf Hansson
2021-08-05  4:05           ` Viresh Kumar
2021-07-20  7:07 ` [PATCH v5 2/2] arm64: dts: sc7180: Add required-opps for i2c Rajendra Nayak

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