On 23/09/2021 10:06, Neil Armstrong wrote:
From: Benoit Parrot <bparrot@xxxxxx>
Global shared resources (like hw overlays) for omapdrm are implemented
as a part of atomic state using the drm_private_obj infrastructure
available in the atomic core.
omap_global_state is introduced as a drm atomic private object. The two
funcs omap_get_global_state() and omap_get_existing_global_state() are
the two variants that will be used to access omap_global_state.
drm_mode_config_init() needs to be called earlier because it
creates/initializes the private_obj link list maintained by the atomic
framework. The private_obj link list has to exist prior to calling
drm_atomic_private_obj_init(). Similarly the cleanup handler are
reordered appropriately.
I'm not really familiar with the private object. Did you check how
current drivers use it? These patches are 3 years old, and things might
have changed around the private object.
Signed-off-by: Benoit Parrot <bparrot@xxxxxx>
Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/gpu/drm/omapdrm/omap_drv.c | 91 +++++++++++++++++++++++++++++-
drivers/gpu/drm/omapdrm/omap_drv.h | 21 +++++++
2 files changed, 109 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c b/drivers/gpu/drm/omapdrm/omap_drv.c
index b994014b22e8..c7912374d393 100644
--- a/drivers/gpu/drm/omapdrm/omap_drv.c
+++ b/drivers/gpu/drm/omapdrm/omap_drv.c
@@ -128,6 +128,82 @@ static const struct drm_mode_config_funcs omap_mode_config_funcs = {
.atomic_commit = drm_atomic_helper_commit,
};
+/* Global/shared object state funcs */
+
+/*
+ * This is a helper that returns the private state currently in operation.
+ * Note that this would return the "old_state" if called in the atomic check
+ * path, and the "new_state" after the atomic swap has been done.
+ */
+struct omap_global_state *
+omap_get_existing_global_state(struct omap_drm_private *priv)
+{
+ return to_omap_global_state(priv->glob_obj.state);
+}
+
+/*
+ * This acquires the modeset lock set aside for global state, creates
+ * a new duplicated private object state.
+ */
+struct omap_global_state *__must_check
+omap_get_global_state(struct drm_atomic_state *s)
+{
+ struct omap_drm_private *priv = s->dev->dev_private;
+ struct drm_private_state *priv_state;
+
+ priv_state = drm_atomic_get_private_obj_state(s, &priv->glob_obj);
+ if (IS_ERR(priv_state))
+ return ERR_CAST(priv_state);
+
+ return to_omap_global_state(priv_state);
+}
+
+static struct drm_private_state *
+omap_global_duplicate_state(struct drm_private_obj *obj)
+{
+ struct omap_global_state *state;
+
+ state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return NULL;
+
+ __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
+
+ return &state->base;
+}
+
+static void omap_global_destroy_state(struct drm_private_obj *obj,
+ struct drm_private_state *state)
+{
+ struct omap_global_state *omap_state = to_omap_global_state(state);
+
+ kfree(omap_state);
+}
+
+static const struct drm_private_state_funcs omap_global_state_funcs = {
+ .atomic_duplicate_state = omap_global_duplicate_state,
+ .atomic_destroy_state = omap_global_destroy_state,
+};
+
+static int omap_global_obj_init(struct drm_device *dev)
+{
+ struct omap_drm_private *priv = dev->dev_private;
+ struct omap_global_state *state;
+
+ state = kzalloc(sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return -ENOMEM;
+
+ drm_atomic_private_obj_init(dev, &priv->glob_obj, &state->base,
+ &omap_global_state_funcs);
+ return 0;
+}
+
+static void omap_global_obj_fini(struct omap_drm_private *priv)
+{
+ drm_atomic_private_obj_fini(&priv->glob_obj);
+}
+
static void omap_disconnect_pipelines(struct drm_device *ddev)
{
struct omap_drm_private *priv = ddev->dev_private;
@@ -231,8 +307,6 @@ static int omap_modeset_init(struct drm_device *dev)
if (!omapdss_stack_is_ready())
return -EPROBE_DEFER;
- drm_mode_config_init(dev);
-
ret = omap_modeset_init_properties(dev);
if (ret < 0)
return ret;
@@ -583,10 +657,16 @@ static int omapdrm_init(struct omap_drm_private *priv, struct device *dev)
omap_gem_init(ddev);
- ret = omap_hwoverlays_init(priv);
+ drm_mode_config_init(ddev);
+
+ ret = omap_global_obj_init(ddev);
if (ret)
goto err_gem_deinit;
+ ret = omap_hwoverlays_init(priv);
+ if (ret)
+ goto err_free_priv_obj;
+
ret = omap_modeset_init(ddev);
if (ret) {
dev_err(priv->dev, "omap_modeset_init failed: ret=%d\n", ret);
@@ -624,7 +704,10 @@ static int omapdrm_init(struct omap_drm_private *priv, struct device *dev)
omap_modeset_fini(ddev);
err_free_overlays:
omap_hwoverlays_destroy(priv);
+err_free_priv_obj:
+ omap_global_obj_fini(priv);
err_gem_deinit:
+ drm_mode_config_cleanup(ddev);
omap_gem_deinit(ddev);
destroy_workqueue(priv->wq);
omap_disconnect_pipelines(ddev);
@@ -649,6 +732,8 @@ static void omapdrm_cleanup(struct omap_drm_private *priv)
omap_modeset_fini(ddev);
omap_hwoverlays_destroy(priv);
+ omap_global_obj_fini(priv);
+ drm_mode_config_cleanup(ddev);
omap_gem_deinit(ddev);
destroy_workqueue(priv->wq);
diff --git a/drivers/gpu/drm/omapdrm/omap_drv.h b/drivers/gpu/drm/omapdrm/omap_drv.h
index b4d9c2062723..280cdd27bc8e 100644
--- a/drivers/gpu/drm/omapdrm/omap_drv.h
+++ b/drivers/gpu/drm/omapdrm/omap_drv.h
@@ -14,6 +14,7 @@
#include "dss/omapdss.h"
#include "dss/dss.h"
+#include <drm/drm_atomic.h>
#include <drm/drm_gem.h>
#include <drm/omap_drm.h>
@@ -41,6 +42,15 @@ struct omap_drm_pipeline {
unsigned int alias_id;
};
+/*
+ * Global private object state for tracking resources that are shared across
+ * multiple kms objects (planes/crtcs/etc).
+ */
+#define to_omap_global_state(x) container_of(x, struct omap_global_state, base)
Add empty line here.
+struct omap_global_state {
+ struct drm_private_state base;
+};
+
struct omap_drm_private {
struct drm_device *ddev;
struct device *dev;
@@ -61,6 +71,13 @@ struct omap_drm_private {
unsigned int num_ovls;
struct omap_hw_overlay *overlays[8];
+ /*
+ * Global private object state, Do not access directly, use
+ * omap_global_get_state()
+ */
+ struct drm_modeset_lock glob_obj_lock;
This is not used... What am I missing?
+ struct drm_private_obj glob_obj;
+
struct drm_fb_helper *fbdev;
struct workqueue_struct *wq;
@@ -88,5 +105,9 @@ struct omap_drm_private {
void omap_debugfs_init(struct drm_minor *minor);
+struct omap_global_state *__must_check
+omap_get_global_state(struct drm_atomic_state *s);
+struct omap_global_state *
+omap_get_existing_global_state(struct omap_drm_private *priv);
These could also be separated by empty lines. At least to my eyes it
gets confusing if those declarations are not separated.
Tomi
