drm/lima: Add optional devfreq and cooling device support

Most platforms with a Mali-400 or Mali-450 GPU also have support for
changing the GPU clock frequency. Add devfreq support so the GPU clock
rate is updated based on the actual GPU usage when the
"operating-points-v2" property is present in the board.dts.

The actual devfreq code is taken from panfrost_devfreq.c and modified so
it matches what the lima hardware needs:
- a call to dev_pm_opp_set_clkname() during initialization because there
  are two clocks on Mali-4x0 IPs. "core" is the one that actually clocks
  the GPU so we need to control it using devfreq.
- locking when reading or writing the devfreq statistics because (unlike
  than panfrost) we have multiple PP and GP IRQs which may finish jobs
  concurrently.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200319203427.2259891-3-martin.blumenstingl@googlemail.com

1 files changed, 12 insertions, 2 deletions

diff --git a/drivers/gpu/drm/lima/lima_drv.c b/drivers/gpu/drm/lima/lima_drv.c
index 97ed70c36340..bbbdc8455e2f 100644
--- a/drivers/gpu/drm/lima/lima_drv.c
+++ b/drivers/gpu/drm/lima/lima_drv.c
@@ -10,6 +10,7 @@
 #include <drm/drm_prime.h>
 #include <drm/lima_drm.h>
 
+#include "lima_device.h"
 #include "lima_drv.h"
 #include "lima_gem.h"
 #include "lima_vm.h"
@@ -397,13 +398,19 @@ static int lima_pdev_probe(struct platform_device *pdev)
 	if (err)
 		goto err_out1;
 
+	err = lima_devfreq_init(ldev);
+	if (err) {
+		dev_err(&pdev->dev, "Fatal error during devfreq init\n");
+		goto err_out2;
+	}
+
 	/*
 	 * Register the DRM device with the core and the connectors with
 	 * sysfs.
 	 */
 	err = drm_dev_register(ddev, 0);
 	if (err < 0)
-		goto err_out2;
+		goto err_out3;
 
 	platform_set_drvdata(pdev, ldev);
 
@@ -412,8 +419,10 @@ static int lima_pdev_probe(struct platform_device *pdev)
 
 	return 0;
 
-err_out2:
+err_out3:
 	lima_device_fini(ldev);
+err_out2:
+	lima_devfreq_fini(ldev);
 err_out1:
 	drm_dev_put(ddev);
 err_out0:
@@ -429,6 +438,7 @@ static int lima_pdev_remove(struct platform_device *pdev)
 	sysfs_remove_bin_file(&ldev->dev->kobj, &lima_error_state_attr);
 	platform_set_drvdata(pdev, NULL);
 	drm_dev_unregister(ddev);
+	lima_devfreq_fini(ldev);
 	lima_device_fini(ldev);
 	drm_dev_put(ddev);
 	lima_sched_slab_fini();