Re: [PATCH 10/15] drm/panfrost: add regulators to devfreq

[Steven Price]

On 10/05/2020 17:55, Clément Péron wrote:

Some OPP tables specify voltage for each frequency. Devfreq can
handle these regulators but they should be get only 1 time to avoid
issue and know who is in charge.

If OPP table is probe don't init regulator.

Signed-off-by: Clément Péron <peron.c...@gmail.com>

This looks like it should work - thanks for doing this!

Reviewed-by: Steven Price <steven.pr...@arm.com>

---
  drivers/gpu/drm/panfrost/panfrost_devfreq.c | 19 +++++++++++++++++++
  drivers/gpu/drm/panfrost/panfrost_devfreq.h |  2 ++
  drivers/gpu/drm/panfrost/panfrost_device.c  | 11 +++++++----
  3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c 
b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
index fce21c682414..9ffea0d4a087 100644
--- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c
+++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
@@ -93,6 +93,7 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
        unsigned long cur_freq;
        struct device *dev = &pfdev->pdev->dev;
        struct devfreq *devfreq;
+       struct opp_table *opp_table;
        struct thermal_cooling_device *cooling;
        struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;

@@ -102,6 +103,19 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev) spin_lock_init(&pfdevfreq->lock); + opp_table = dev_pm_opp_set_regulators(dev, pfdev->comp->supply_names,

+                                             pfdev->comp->num_supplies);
+       if (IS_ERR(opp_table)) {
+               ret = PTR_ERR(opp_table);
+               /* Continue if the optional regulator is missing */
+               if (ret != -ENODEV) {
+                       DRM_DEV_ERROR(dev, "Couldn't set OPP regulators\n");
+                       goto err_fini;
+               }
+       } else {
+               pfdevfreq->regulators_opp_table = opp_table;
+       }
+
        ret = dev_pm_opp_of_add_table(dev);
        if (ret) {
                DRM_DEV_ERROR(dev, "Couldn't add OPP table\n");
@@ -157,6 +171,11 @@ void panfrost_devfreq_fini(struct panfrost_device *pfdev)
                dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
                pfdevfreq->opp_of_table_added = false;
        }
+
+       if (pfdevfreq->regulators_opp_table) {
+               dev_pm_opp_put_regulators(pfdevfreq->regulators_opp_table);
+               pfdevfreq->regulators_opp_table = NULL;
+       }
  }

void panfrost_devfreq_resume(struct panfrost_device *pfdev)

diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.h 
b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
index add203cb00c2..347cde4786cf 100644
--- a/drivers/gpu/drm/panfrost/panfrost_devfreq.h
+++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
@@ -8,12 +8,14 @@
  #include <linux/ktime.h>

struct devfreq;

+struct opp_table;
  struct thermal_cooling_device;

struct panfrost_device; struct panfrost_devfreq {

        struct devfreq *devfreq;
+       struct opp_table *regulators_opp_table;
        struct thermal_cooling_device *cooling;
        bool opp_of_table_added;

diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c

index 67eedf64e82d..8b17fb2e3369 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.c
+++ b/drivers/gpu/drm/panfrost/panfrost_device.c
@@ -222,10 +222,13 @@ int panfrost_device_init(struct panfrost_device *pfdev)
                goto err_out0;
        }

- err = panfrost_regulator_init(pfdev);

-       if (err) {
-               dev_err(pfdev->dev, "regulator init failed %d\n", err);
-               goto err_out1;
+       /* OPP will handle regulators */
+       if (!pfdev->pfdevfreq.opp_of_table_added) {
+               err = panfrost_regulator_init(pfdev);
+               if (err) {
+                       dev_err(pfdev->dev, "regulator init failed %d\n", err);
+                       goto err_out1;
+               }
        }

err = panfrost_reset_init(pfdev);