[PATCH 6/8] drm/sun4i: sun4i_layer: Wire in the frontend
Thomas van Kleef
thomas at vitsch.nl
Wed Dec 13 16:23:04 UTC 2017
On 13-12-17 16:33, Maxime Ripard wrote:
> Now that we have a driver, we can make use of it. This is done by
> adding a flag to our custom plane state that will trigger whether we should
> use the frontend on that particular plane or not.
>
> The rest is just plumbing to set up the backend to not perform the DMA but
> receive its data from the frontend.
>
> Note that we're still not making any use of the frontend itself, as no one
> is setting the flag yet.
>
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> ---
> drivers/gpu/drm/sun4i/sun4i_backend.c | 53 ++++++++++++++++++++++++++++-
> drivers/gpu/drm/sun4i/sun4i_backend.h | 3 ++-
> drivers/gpu/drm/sun4i/sun4i_layer.c | 27 ++++++++++++--
> drivers/gpu/drm/sun4i/sun4i_layer.h | 1 +-
> 4 files changed, 81 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_backend.c b/drivers/gpu/drm/sun4i/sun4i_backend.c
> index e83e1fe43823..f1d19767c55d 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_backend.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_backend.c
> @@ -26,6 +26,7 @@
>
> #include "sun4i_backend.h"
> #include "sun4i_drv.h"
> +#include "sun4i_frontend.h"
> #include "sun4i_layer.h"
> #include "sunxi_engine.h"
>
> @@ -203,6 +204,30 @@ int sun4i_backend_update_layer_formats(struct sun4i_backend *backend,
> return 0;
> }
>
> +int sun4i_backend_update_layer_frontend(struct sun4i_backend *backend,
> + int layer, uint32_t fmt)
> +{
> + u32 val;
> + int ret;
> +
> + ret = sun4i_backend_drm_format_to_layer(NULL, fmt, &val);
> + if (ret) {
> + DRM_DEBUG_DRIVER("Invalid format\n");
> + return ret;
> + }
> +
> + regmap_update_bits(backend->engine.regs,
> + SUN4I_BACKEND_ATTCTL_REG0(layer),
> + SUN4I_BACKEND_ATTCTL_REG0_LAY_VDOEN,
> + SUN4I_BACKEND_ATTCTL_REG0_LAY_VDOEN);
> +
> + regmap_update_bits(backend->engine.regs,
> + SUN4I_BACKEND_ATTCTL_REG1(layer),
> + SUN4I_BACKEND_ATTCTL_REG1_LAY_FBFMT, val);
> +
> + return 0;
> +}
> +
> int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
> int layer, struct drm_plane *plane)
> {
> @@ -330,6 +355,34 @@ static int sun4i_backend_of_get_id(struct device_node *node)
> return ret;
> }
>
> +static struct sun4i_frontend *sun4i_backend_find_frontend(struct sun4i_drv *drv,
> + struct device_node *node)
> +{
> + struct device_node *port, *ep, *remote;
> + struct sun4i_frontend *frontend;
> +
> + port = of_graph_get_port_by_id(node, 0);
> + if (!port)
> + return ERR_PTR(-EINVAL);
> +
> + for_each_available_child_of_node(port, ep) {
> + remote = of_graph_get_remote_port_parent(ep);
> + if (!remote)
> + continue;
> +
> + /* does this node match any registered engines? */
> + list_for_each_entry(frontend, &drv->frontend_list, list) {
> + if (remote == frontend->node) {
> + of_node_put(remote);
> + of_node_put(port);
> + return frontend;
> + }
> + }
> + }
> +
> + return ERR_PTR(-EINVAL);
> +}
> +
> static const struct sunxi_engine_ops sun4i_backend_engine_ops = {
> .commit = sun4i_backend_commit,
> .layers_init = sun4i_layers_init,
> diff --git a/drivers/gpu/drm/sun4i/sun4i_backend.h b/drivers/gpu/drm/sun4i/sun4i_backend.h
> index ba1410fd5410..636a51521e77 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_backend.h
> +++ b/drivers/gpu/drm/sun4i/sun4i_backend.h
> @@ -72,6 +72,7 @@
> #define SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL(x) ((x) << 15)
> #define SUN4I_BACKEND_ATTCTL_REG0_LAY_PRISEL_MASK GENMASK(11, 10)
> #define SUN4I_BACKEND_ATTCTL_REG0_LAY_PRISEL(x) ((x) << 10)
> +#define SUN4I_BACKEND_ATTCTL_REG0_LAY_VDOEN BIT(1)
>
> #define SUN4I_BACKEND_ATTCTL_REG1(l) (0x8a0 + (0x4 * (l)))
> #define SUN4I_BACKEND_ATTCTL_REG1_LAY_HSCAFCT GENMASK(15, 14)
> @@ -171,5 +172,7 @@ int sun4i_backend_update_layer_formats(struct sun4i_backend *backend,
> int layer, struct drm_plane *plane);
> int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
> int layer, struct drm_plane *plane);
> +int sun4i_backend_update_layer_frontend(struct sun4i_backend *backend,
> + int layer, uint32_t in_fmt);
>
> #endif /* _SUN4I_BACKEND_H_ */
> diff --git a/drivers/gpu/drm/sun4i/sun4i_layer.c b/drivers/gpu/drm/sun4i/sun4i_layer.c
> index c3afcf888906..3b58667a06dc 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_layer.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_layer.c
> @@ -15,6 +15,7 @@
> #include <drm/drmP.h>
>
> #include "sun4i_backend.h"
> +#include "sun4i_frontend.h"
> #include "sun4i_layer.h"
> #include "sunxi_engine.h"
>
> @@ -70,21 +71,41 @@ static void sun4i_backend_layer_destroy_state(struct drm_plane *plane,
> static void sun4i_backend_layer_atomic_disable(struct drm_plane *plane,
> struct drm_plane_state *old_state)
> {
> + struct sun4i_layer_state *layer_state = state_to_sun4i_layer_state(old_state);
> struct sun4i_layer *layer = plane_to_sun4i_layer(plane);
> struct sun4i_backend *backend = layer->backend;
> + struct sun4i_frontend *frontend = backend->frontend;
>
> sun4i_backend_layer_enable(backend, layer->id, false);
> +
> + if (layer_state->uses_frontend)
> + sun4i_frontend_exit(frontend);
> }
>
> static void sun4i_backend_layer_atomic_update(struct drm_plane *plane,
> struct drm_plane_state *old_state)
> {
> + struct sun4i_layer_state *layer_state = state_to_sun4i_layer_state(plane->state);
> struct sun4i_layer *layer = plane_to_sun4i_layer(plane);
> struct sun4i_backend *backend = layer->backend;
> + struct sun4i_frontend *frontend = backend->frontend;
> +
> + if (layer_state->uses_frontend) {
> + sun4i_frontend_init(frontend);
> + sun4i_frontend_update_coord(frontend, plane);
> + sun4i_frontend_update_buffer(frontend, plane);
> + sun4i_frontend_update_formats(frontend, plane,
> + DRM_FORMAT_ARGB8888);
> + sun4i_backend_update_layer_frontend(backend, layer->id,
> + DRM_FORMAT_ARGB8888);
> + sun4i_backend_update_layer_coord(backend, layer->id, plane);
> + sun4i_frontend_enable(frontend);
> + } else {
> + sun4i_backend_update_layer_coord(backend, layer->id, plane);
> + sun4i_backend_update_layer_formats(backend, layer->id, plane);
> + sun4i_backend_update_layer_buffer(backend, layer->id, plane);
> + }
>
> - sun4i_backend_update_layer_coord(backend, layer->id, plane);
> - sun4i_backend_update_layer_formats(backend, layer->id, plane);
> - sun4i_backend_update_layer_buffer(backend, layer->id, plane);
> sun4i_backend_layer_enable(backend, layer->id, true);
> }
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_layer.h b/drivers/gpu/drm/sun4i/sun4i_layer.h
> index d2c19348d1b0..75b4868ba87c 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_layer.h
> +++ b/drivers/gpu/drm/sun4i/sun4i_layer.h
> @@ -24,6 +24,7 @@ struct sun4i_layer {
>
> struct sun4i_layer_state {
> struct drm_plane_state state;
> + bool uses_frontend;
> };
>
> static inline struct sun4i_layer *
>
I wondered if the following is still valid?
In file sun4i_layer.c, func sun4i_layers_init
------------------
/*
* The hardware is a bit unusual here.
*
* Even though it supports 4 layers, it does the composition
* in two separate steps.
*
* The first one is assigning a layer to one of its two
* pipes. If more that 1 layer is assigned to the same pipe,
* and if pixels overlaps, the pipe will take the pixel from
* the layer with the highest priority.
*
* The second step is the actual alpha blending, that takes
* the two pipes as input, and uses the eventual alpha
* component to do the transparency between the two.
*
* This two steps scenario makes us unable to guarantee a
* robust alpha blending between the 4 layers in all
* situations. So we just expose two layers, one per pipe. On
* SoCs that support it, sprites could fill the need for more
* layers.
*/
for (i = 0; i < ARRAY_SIZE(sun4i_backend_planes); i++) {
const struct sun4i_plane_desc *plane = &sun4i_backend_planes[i];
struct sun4i_layer *layer;
layer = sun4i_layer_init_one(drm, backend, plane);
if (IS_ERR(layer)) {
dev_err(drm->dev, "Couldn't initialize %s plane\n",
i ? "overlay" : "primary");
return ERR_CAST(layer);
};
DRM_DEBUG_DRIVER("Assigning %s plane to pipe %d\n",
i ? "overlay" : "primary", plane->pipe);
regmap_update_bits(engine->regs, SUN4I_BACKEND_ATTCTL_REG0(i),
SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL_MASK,
SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL(plane->pipe));
layer->id = i;
planes[i] = &layer->plane;
};
-----------------
I have been using the 3rd layer (layer2) as the input for the frontend. This essentially
overlays the other 2 layers. Is it still the case that we can only have 2 layers here?
Or could be present 1 additional layer when it is attached to the frontend?
Perhaps this is not relevant for this patchset.
Regards,
Thomas van Kleef
Vitsch Electronics
http://Vitsch.nl/
http://VitschVPN.nl/
tel: +31-(0)40-7113051
KvK nr: 17174380
BTW nr: NL142748201B01
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