[PATCH v2 06/10] drm/panthor: call into devfreq for current frequency

[Nicolas Frattaroli <nicolas.frattaroli@collabora.com>]

As it stands, panthor keeps a cached current frequency value for when it
wants to retrieve it. This doesn't work well for when things might
switch frequency without panthor's knowledge.

Instead, implement the get_cur_freq operation, and expose it through a
helper function to the rest of panthor.

Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
 drivers/gpu/drm/panthor/panthor_devfreq.c | 33 +++++++++++++++++++++++++++----
 drivers/gpu/drm/panthor/panthor_devfreq.h |  2 ++
 drivers/gpu/drm/panthor/panthor_device.h  |  3 ---
 drivers/gpu/drm/panthor/panthor_drv.c     |  4 +++-
 4 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.c b/drivers/gpu/drm/panthor/panthor_devfreq.c
index 3686515d368db5bb329f4858d4a7247a4957cc24..8903f60c0a3f06313ac2008791c210ff32b6bd52 100644
--- a/drivers/gpu/drm/panthor/panthor_devfreq.c
+++ b/drivers/gpu/drm/panthor/panthor_devfreq.c
@@ -62,7 +62,6 @@ static void panthor_devfreq_update_utilization(struct panthor_devfreq *pdevfreq)
 static int panthor_devfreq_target(struct device *dev, unsigned long *freq,
 				  u32 flags)
 {
-	struct panthor_device *ptdev = dev_get_drvdata(dev);
 	struct dev_pm_opp *opp;
 	int err;
 
@@ -72,8 +71,6 @@ static int panthor_devfreq_target(struct device *dev, unsigned long *freq,
 	dev_pm_opp_put(opp);
 
 	err = dev_pm_opp_set_rate(dev, *freq);
-	if (!err)
-		ptdev->current_frequency = *freq;
 
 	return err;
 }
@@ -115,11 +112,21 @@ static int panthor_devfreq_get_dev_status(struct device *dev,
 	return 0;
 }
 
+static int panthor_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+	struct panthor_device *ptdev = dev_get_drvdata(dev);
+
+	*freq = clk_get_rate(ptdev->clks.core);
+
+	return 0;
+}
+
 static struct devfreq_dev_profile panthor_devfreq_profile = {
 	.timer = DEVFREQ_TIMER_DELAYED,
 	.polling_ms = 50, /* ~3 frames */
 	.target = panthor_devfreq_target,
 	.get_dev_status = panthor_devfreq_get_dev_status,
+	.get_cur_freq = panthor_devfreq_get_cur_freq,
 };
 
 int panthor_devfreq_init(struct panthor_device *ptdev)
@@ -198,7 +205,6 @@ int panthor_devfreq_init(struct panthor_device *ptdev)
 		return PTR_ERR(opp);
 
 	panthor_devfreq_profile.initial_freq = cur_freq;
-	ptdev->current_frequency = cur_freq;
 
 	/*
 	 * Set the recommend OPP this will enable and configure the regulator
@@ -296,3 +302,22 @@ void panthor_devfreq_record_idle(struct panthor_device *ptdev)
 
 	spin_unlock_irqrestore(&pdevfreq->lock, irqflags);
 }
+
+unsigned long panthor_devfreq_get_freq(struct panthor_device *ptdev)
+{
+	struct panthor_devfreq *pdevfreq = ptdev->devfreq;
+	unsigned long freq = 0;
+	int ret;
+
+	if (!pdevfreq || !pdevfreq->devfreq)
+		return 0;
+
+	if (pdevfreq->devfreq->profile->get_cur_freq) {
+		ret = pdevfreq->devfreq->profile->get_cur_freq(ptdev->base.dev,
+							       &freq);
+		if (ret)
+			return 0;
+	}
+
+	return freq;
+}
diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.h b/drivers/gpu/drm/panthor/panthor_devfreq.h
index b7631de695f7d79456478c87e8af5dc47673cd1d..f8e29e02f66cb3281ed4bb4c75cda9bd4df82b92 100644
--- a/drivers/gpu/drm/panthor/panthor_devfreq.h
+++ b/drivers/gpu/drm/panthor/panthor_devfreq.h
@@ -18,4 +18,6 @@ void panthor_devfreq_suspend(struct panthor_device *ptdev);
 void panthor_devfreq_record_busy(struct panthor_device *ptdev);
 void panthor_devfreq_record_idle(struct panthor_device *ptdev);
 
+unsigned long panthor_devfreq_get_freq(struct panthor_device *ptdev);
+
 #endif /* __PANTHOR_DEVFREQ_H__ */
diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
index 4fc7cf2aeed577f623aac73ed287d6327645ecaa..a14239c8f9ca9229d8d6d36d327e6fd6d05f8f2f 100644
--- a/drivers/gpu/drm/panthor/panthor_device.h
+++ b/drivers/gpu/drm/panthor/panthor_device.h
@@ -200,9 +200,6 @@ struct panthor_device {
 	/** @profile_mask: User-set profiling flags for job accounting. */
 	u32 profile_mask;
 
-	/** @current_frequency: Device clock frequency at present. Set by DVFS*/
-	unsigned long current_frequency;
-
 	/** @fast_rate: Maximum device clock frequency. Set by DVFS */
 	unsigned long fast_rate;
 
diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index fdbe89ef7f43c54d705b90275917dfdee16a0152..ba871466d7e05a95b51b3e5bb6723c587410f3d8 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -25,6 +25,7 @@
 #include <drm/gpu_scheduler.h>
 #include <drm/panthor_drm.h>
 
+#include "panthor_devfreq.h"
 #include "panthor_device.h"
 #include "panthor_fw.h"
 #include "panthor_gem.h"
@@ -1519,7 +1520,8 @@ static void panthor_gpu_show_fdinfo(struct panthor_device *ptdev,
 		drm_printf(p, "drm-cycles-panthor:\t%llu\n", pfile->stats.cycles);
 
 	drm_printf(p, "drm-maxfreq-panthor:\t%lu Hz\n", ptdev->fast_rate);
-	drm_printf(p, "drm-curfreq-panthor:\t%lu Hz\n", ptdev->current_frequency);
+	drm_printf(p, "drm-curfreq-panthor:\t%lu Hz\n",
+		   panthor_devfreq_get_freq(ptdev));
 }
 
 static void panthor_show_internal_memory_stats(struct drm_printer *p, struct drm_file *file)

-- 
2.51.0