Re: [PATCH v10 5/9] drm/mediatek: Add connector dynamic selection capability

From: Jason-JH Lin (林睿祥)
Date: Mon Oct 02 2023 - 03:15:03 EST


Hi Angelo,

Thanks for the reviews.

On Thu, 2023-09-28 at 12:00 +0200, AngeloGioacchino Del Regno wrote:
> Il 27/09/23 17:38, Jason-JH.Lin ha scritto:
> > Add dynamic select available connector flow in
> > mtk_drm_crtc_create()
> > and mtk_drm_crtc_atomic_enable().
> >
> > In mtk_drm_crtc_create(), if there is a connector routes array in
> > drm
> > driver data, all components definded in the connector routes array
> > will
> > be checked and their encoder_index will be set.
> >
> > In mtk_drm_crtc_atomic_enable(), crtc will check its encoder_index
> > to
> > identify which componet in the connector routes array should
> > append.
> >
> > Signed-off-by: Nancy Lin <nancy.lin@xxxxxxxxxxxx>
> > Signed-off-by: Nathan Lu <nathan.lu@xxxxxxxxxxxx>
> > Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> > Tested-by: Fei Shao <fshao@xxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 78
> > ++++++++++++++++++++-
> > drivers/gpu/drm/mediatek/mtk_drm_crtc.h | 5 +-
> > drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 27 ++++++-
> > drivers/gpu/drm/mediatek/mtk_drm_drv.c | 13 +++-
> > drivers/gpu/drm/mediatek/mtk_drm_drv.h | 7 ++
> > 5 files changed, 123 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > index b6fa4ad2f94d..8eb4d2646a76 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > @@ -63,6 +63,8 @@ struct mtk_drm_crtc {
> > struct mtk_mutex *mutex;
> > unsigned int ddp_comp_nr;
> > struct mtk_ddp_comp **ddp_comp;
> > + unsigned int num_conn_routes;
> > + const struct mtk_drm_route *conn_routes;
> >
> > /* lock for display hardware access */
> > struct mutex hw_lock;
> > @@ -647,6 +649,45 @@ static void mtk_drm_crtc_disable_vblank(struct
> > drm_crtc *crtc)
> > mtk_ddp_comp_disable_vblank(comp);
> > }
> >
> > +static void mtk_drm_crtc_update_output(struct drm_crtc *crtc,
> > + struct drm_atomic_state *state)
> > +{
> > + int crtc_index = drm_crtc_index(crtc);
> > + int i;
> > + struct device *dev;
> > + struct drm_crtc_state *crtc_state = state-
> > >crtcs[crtc_index].new_state;
> > + struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> > + struct mtk_drm_private *priv = crtc->dev->dev_private;
> > + unsigned int comp_id;
>
> You're not using comp_id globally in this function....

OK, I'll move it to the for loop below.

>
> > + unsigned int encoder_mask = crtc_state->encoder_mask;
> > +
> > + if (!crtc_state->connectors_changed)
> > + return;
> > +
> > + if (!mtk_crtc->num_conn_routes)
> > + return;
> > +
> > + priv = priv->all_drm_private[crtc_index];
>
> This is a bit confusing. You're reassigning priv: please avoid that.
> I would prefer directly seeing the final assignment, or otherwise two
> pointers.
>
> struct mtk_drm_private *priv;
>
> if ....
> ...........
>
> priv = crtc->dev->dev_private->all_drm_private[crtc_index];
>

OK, because the type of dev_private is void*. I'll change the
assignment to:

priv = ((struct mtk_drm_private *)crtc->dev->dev_private)-
>all_drm_private[crtc_index];

> > + dev = priv->dev;
> > +
> > + dev_dbg(dev, "connector change:%d, encoder mask:0x%x for
> > crtc:%d\n",
> > + crtc_state->connectors_changed, encoder_mask,
> > crtc_index);
> > +
> > + for (i = 0; i < mtk_crtc->num_conn_routes; i++) {
> > + struct mtk_ddp_comp *comp;
>
> ...so you can move it here...

OK, I'll move it here.

> unsigned int comp_id = mtk_crtc-
> >conn_routes[i].route_ddp;
> struct mtk_ddp_comp *comp = &priv->ddp_comp[comp_id];
>
> > +
> > + comp_id = mtk_crtc->conn_routes[i].route_ddp;
> > + comp = &priv->ddp_comp[comp_id];
> > + if (comp->encoder_index >= 0 &&
> > + encoder_mask & BIT(comp->encoder_index)) {
>
> For readability, I would prefer to see
>
> if (comp->encoder_index >= 0 &&
> (encoder_mask & BIT(comp->encoder_index))) {
>
> ...but I don't have strong opinions on that.
>

OK, I'll modify it.

> > + mtk_crtc->ddp_comp[mtk_crtc->ddp_comp_nr - 1] =
> > comp;
> > + dev_dbg(dev, "Add comp_id: %d at path index
> > %d\n",
> > + comp->id, mtk_crtc->ddp_comp_nr - 1);
> > + break;
> > + }
> > + }
> > +}
> > +
> > int mtk_drm_crtc_plane_check(struct drm_crtc *crtc, struct
> > drm_plane *plane,
> > struct mtk_plane_state *state)
> > {
> > @@ -679,6 +720,8 @@ static void mtk_drm_crtc_atomic_enable(struct
> > drm_crtc *crtc,
> >
> > DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);
> >
> > + mtk_drm_crtc_update_output(crtc, state);
> > +
>
> What's the point of updating the output before
> pm_runtime_resume_and_get()?
> If PM resume fails we're not enabling the CRTC so the update is
> actually useless.
>
> Please move this after PM resume: that will also possibly come handy
> in the future.

OK, I'll move this after pm_runtime_resume_and_get().

>
>
> > ret = pm_runtime_resume_and_get(comp->dev);
> > if (ret < 0) {
> > DRM_DEV_ERROR(comp->dev, "Failed to enable power
> > domain: %d\n", ret);
> > @@ -884,7 +927,8 @@ struct device *mtk_drm_crtc_dma_dev_get(struct
> > drm_crtc *crtc)
> >
> > int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > const unsigned int *path, unsigned int
> > path_len,
> > - int priv_data_index)
> > + int priv_data_index, const struct mtk_drm_route
> > *conn_routes,
> > + unsigned int num_conn_routes)
> > {
> > struct mtk_drm_private *priv = drm_dev->dev_private;
> > struct device *dev = drm_dev->dev;
> > @@ -935,7 +979,8 @@ int mtk_drm_crtc_create(struct drm_device
> > *drm_dev,
> >
> > mtk_crtc->mmsys_dev = priv->mmsys_dev;
> > mtk_crtc->ddp_comp_nr = path_len;
> > - mtk_crtc->ddp_comp = devm_kmalloc_array(dev, mtk_crtc-
> > >ddp_comp_nr,
> > + mtk_crtc->ddp_comp = devm_kmalloc_array(dev,
> > + mtk_crtc->ddp_comp_nr +
> > (conn_routes ? 1 : 0),
> > sizeof(*mtk_crtc-
> > >ddp_comp),
> > GFP_KERNEL);
> > if (!mtk_crtc->ddp_comp)
> > @@ -1038,5 +1083,34 @@ int mtk_drm_crtc_create(struct drm_device
> > *drm_dev,
> > init_waitqueue_head(&mtk_crtc->cb_blocking_queue);
> > }
> > #endif
> > +
> > + if (conn_routes) {
> > + struct device_node *node;
> > + struct mtk_ddp_comp *comp;
> > + unsigned int comp_id;
> > +
> > + for (i = 0; i < num_conn_routes; i++) {
>
> Same here, you're locally using comp_id, node and comp *only* in the
> for loop....
>

OK I'll move it here.

> unsigned int comp_id =
> conn_routes[i].route_ddp;
> struct device_node *node = priv-
> >comp_node[comp_id];
> struct mtk_ddp_comp *comp = &priv-
> >ddp_comp[comp_id];
>
> > + comp_id = conn_routes[i].route_ddp;
> > + node = priv->comp_node[comp_id];
> > + comp = &priv->ddp_comp[comp_id];
> > +
> > + if (!comp->dev) {
> > + dev_dbg(dev, "comp_id:%d, Component
> > %pOF not initialized\n",
> > + comp_id, node);
> > + /* mark encoder_index to -1, if route
> > comp device is not enabled */
> > + comp->encoder_index = -1;
> > + continue;
> > + }
> > +
> > + mtk_ddp_comp_encoder_index_set(&priv-
> > >ddp_comp[comp_id]);
> > + }
> > +
> > + mtk_crtc->num_conn_routes = num_conn_routes;
> > + mtk_crtc->conn_routes = conn_routes;
> > +
> > + /* increase ddp_comp_nr at the end of
> > mtk_drm_crtc_create */
> > + mtk_crtc->ddp_comp_nr++;
> > + }
> > +
> > return 0;
> > }
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > index 3e9046993d09..3c224595fa71 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > @@ -8,6 +8,7 @@
> >
> > #include <drm/drm_crtc.h>
> > #include "mtk_drm_ddp_comp.h"
> > +#include "mtk_drm_drv.h"
> > #include "mtk_drm_plane.h"
> >
> > #define MTK_LUT_SIZE 512
> > @@ -18,7 +19,9 @@ void mtk_drm_crtc_commit(struct drm_crtc *crtc);
> > int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > const unsigned int *path,
> > unsigned int path_len,
> > - int priv_data_index);
> > + int priv_data_index,
> > + const struct mtk_drm_route *conn_routes,
> > + unsigned int num_conn_routes);
> > int mtk_drm_crtc_plane_check(struct drm_crtc *crtc, struct
> > drm_plane *plane,
> > struct mtk_plane_state *state);
> > void mtk_drm_crtc_async_update(struct drm_crtc *crtc, struct
> > drm_plane *plane,
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > index 771f4e173353..4ddb5e561116 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > @@ -507,6 +507,23 @@ static bool mtk_drm_find_comp_in_ddp(struct
> > device *dev,
> > return false;
> > }
> >
> > +static int mtk_drm_find_comp_in_ddp_conn_path(struct device *dev,
> > + const struct
> > mtk_drm_route *routes,
> > + unsigned int num_routes,
> > + struct mtk_ddp_comp
> > *ddp_comp)
> > +{
> > + unsigned int i;
> > +
> > + if (!routes)
> > + return -EINVAL;
> > +
> > + for (i = 0; i < num_routes; i++)
> > + if (dev == ddp_comp[routes[i].route_ddp].dev)
> > + return BIT(routes[i].crtc_id);
> > +
> > + return -ENODEV;
> > +}
> > +
> > int mtk_ddp_comp_get_id(struct device_node *node,
> > enum mtk_ddp_comp_type comp_type)
> > {
> > @@ -538,7 +555,15 @@ unsigned int
> > mtk_drm_find_possible_crtc_by_comp(struct drm_device *drm,
> > private->data->third_len,
> > private->ddp_comp))
> > ret = BIT(2);
> > else
> > - DRM_INFO("Failed to find comp in ddp table\n");
> > + ret = mtk_drm_find_comp_in_ddp_conn_path(dev,
> > + private->data-
> > >conn_routes,
> > + private->data-
> > >num_conn_routes,
> > + private-
> > >ddp_comp);
> > +
> > + if (ret <= 0) {
> > + DRM_INFO("Failed to find comp in ddp table, ret =%d\n",
> > ret);
> > + ret = 0;
>
> Why are you returning 0 for error here?!

Because this function return 0 means not found any valid crtc bits.
Should I change this?

Regards,
Jason-JH.Lin

>
> > + }
> >
> > return ret;
> > }
>
> Regards,
> Angelo
>