drm: Add helper for simple display pipeline

Provides helper functions for drivers that have a simple display
pipeline. Plane, crtc and encoder are collapsed into one entity.

Changes since v4:
- Remove drm_connector_register() call
- Forgot to assign pipe->connector

Changes since v3:
- (struct drm_simple_display_pipe *)->funcs should be const

Changes since v2:
- Drop Kconfig knob DRM_KMS_HELPER
- Expand documentation

Changes since v1:
- Add DOC header and add to gpu.tmpl
- Fix docs: @funcs is optional, "negative error code",
  "This hook is optional."
- Add checks to drm_simple_kms_plane_atomic_check()

Cc: jsarha@ti.com
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465570559-14238-1-git-send-email-noralf@tronnes.org
This commit is contained in:
Noralf Trønnes 2016-06-10 16:55:59 +02:00 committed by Daniel Vetter
parent c2a441fe8f
commit 5b8090747a
4 changed files with 307 additions and 1 deletions

View File

@ -1688,6 +1688,12 @@ void intel_crt_init(struct drm_device *dev)
!Edrivers/gpu/drm/drm_panel.c
!Pdrivers/gpu/drm/drm_panel.c drm panel
</sect2>
<sect2>
<title>Simple KMS Helper Reference</title>
!Iinclude/drm/drm_simple_kms_helper.h
!Edrivers/gpu/drm/drm_simple_kms_helper.c
!Pdrivers/gpu/drm/drm_simple_kms_helper.c overview
</sect2>
</sect1>
<!-- Internals: kms properties -->

View File

@ -23,7 +23,8 @@ drm-$(CONFIG_AGP) += drm_agpsupport.o
drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o \
drm_plane_helper.o drm_dp_mst_topology.o drm_atomic_helper.o \
drm_kms_helper_common.o drm_dp_dual_mode_helper.o
drm_kms_helper_common.o drm_dp_dual_mode_helper.o \
drm_simple_kms_helper.o
drm_kms_helper-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o

View File

@ -0,0 +1,205 @@
/*
* Copyright (C) 2016 Noralf Trønnes
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_simple_kms_helper.h>
#include <linux/slab.h>
/**
* DOC: overview
*
* This helper library provides helpers for drivers for simple display
* hardware.
*
* drm_simple_display_pipe_init() initializes a simple display pipeline
* which has only one full-screen scanout buffer feeding one output. The
* pipeline is represented by struct &drm_simple_display_pipe and binds
* together &drm_plane, &drm_crtc and &drm_encoder structures into one fixed
* entity. Some flexibility for code reuse is provided through a separately
* allocated &drm_connector object and supporting optional &drm_bridge
* encoder drivers.
*/
static const struct drm_encoder_funcs drm_simple_kms_encoder_funcs = {
.destroy = drm_encoder_cleanup,
};
static void drm_simple_kms_crtc_enable(struct drm_crtc *crtc)
{
struct drm_simple_display_pipe *pipe;
pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
if (!pipe->funcs || !pipe->funcs->enable)
return;
pipe->funcs->enable(pipe, crtc->state);
}
static void drm_simple_kms_crtc_disable(struct drm_crtc *crtc)
{
struct drm_simple_display_pipe *pipe;
pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
if (!pipe->funcs || !pipe->funcs->disable)
return;
pipe->funcs->disable(pipe);
}
static const struct drm_crtc_helper_funcs drm_simple_kms_crtc_helper_funcs = {
.disable = drm_simple_kms_crtc_disable,
.enable = drm_simple_kms_crtc_enable,
};
static const struct drm_crtc_funcs drm_simple_kms_crtc_funcs = {
.reset = drm_atomic_helper_crtc_reset,
.destroy = drm_crtc_cleanup,
.set_config = drm_atomic_helper_set_config,
.page_flip = drm_atomic_helper_page_flip,
.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
};
static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane,
struct drm_plane_state *plane_state)
{
struct drm_rect src = {
.x1 = plane_state->src_x,
.y1 = plane_state->src_y,
.x2 = plane_state->src_x + plane_state->src_w,
.y2 = plane_state->src_y + plane_state->src_h,
};
struct drm_rect dest = {
.x1 = plane_state->crtc_x,
.y1 = plane_state->crtc_y,
.x2 = plane_state->crtc_x + plane_state->crtc_w,
.y2 = plane_state->crtc_y + plane_state->crtc_h,
};
struct drm_rect clip = { 0 };
struct drm_simple_display_pipe *pipe;
struct drm_crtc_state *crtc_state;
bool visible;
int ret;
pipe = container_of(plane, struct drm_simple_display_pipe, plane);
crtc_state = drm_atomic_get_existing_crtc_state(plane_state->state,
&pipe->crtc);
if (crtc_state->enable != !!plane_state->crtc)
return -EINVAL; /* plane must match crtc enable state */
if (!crtc_state->enable)
return 0; /* nothing to check when disabling or disabled */
clip.x2 = crtc_state->adjusted_mode.hdisplay;
clip.y2 = crtc_state->adjusted_mode.vdisplay;
ret = drm_plane_helper_check_update(plane, &pipe->crtc,
plane_state->fb,
&src, &dest, &clip,
DRM_PLANE_HELPER_NO_SCALING,
DRM_PLANE_HELPER_NO_SCALING,
false, true, &visible);
if (ret)
return ret;
if (!visible)
return -EINVAL;
if (!pipe->funcs || !pipe->funcs->check)
return 0;
return pipe->funcs->check(pipe, plane_state, crtc_state);
}
static void drm_simple_kms_plane_atomic_update(struct drm_plane *plane,
struct drm_plane_state *pstate)
{
struct drm_simple_display_pipe *pipe;
pipe = container_of(plane, struct drm_simple_display_pipe, plane);
if (!pipe->funcs || !pipe->funcs->update)
return;
pipe->funcs->update(pipe, pstate);
}
static const struct drm_plane_helper_funcs drm_simple_kms_plane_helper_funcs = {
.atomic_check = drm_simple_kms_plane_atomic_check,
.atomic_update = drm_simple_kms_plane_atomic_update,
};
static const struct drm_plane_funcs drm_simple_kms_plane_funcs = {
.update_plane = drm_atomic_helper_update_plane,
.disable_plane = drm_atomic_helper_disable_plane,
.destroy = drm_plane_cleanup,
.reset = drm_atomic_helper_plane_reset,
.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
};
/**
* drm_simple_display_pipe_init - Initialize a simple display pipeline
* @dev: DRM device
* @pipe: simple display pipe object to initialize
* @funcs: callbacks for the display pipe (optional)
* @formats: array of supported formats (%DRM_FORMAT_*)
* @format_count: number of elements in @formats
* @connector: connector to attach and register
*
* Sets up a display pipeline which consist of a really simple
* plane-crtc-encoder pipe coupled with the provided connector.
* Teardown of a simple display pipe is all handled automatically by the drm
* core through calling drm_mode_config_cleanup(). Drivers afterwards need to
* release the memory for the structure themselves.
*
* Returns:
* Zero on success, negative error code on failure.
*/
int drm_simple_display_pipe_init(struct drm_device *dev,
struct drm_simple_display_pipe *pipe,
const struct drm_simple_display_pipe_funcs *funcs,
const uint32_t *formats, unsigned int format_count,
struct drm_connector *connector)
{
struct drm_encoder *encoder = &pipe->encoder;
struct drm_plane *plane = &pipe->plane;
struct drm_crtc *crtc = &pipe->crtc;
int ret;
pipe->connector = connector;
pipe->funcs = funcs;
drm_plane_helper_add(plane, &drm_simple_kms_plane_helper_funcs);
ret = drm_universal_plane_init(dev, plane, 0,
&drm_simple_kms_plane_funcs,
formats, format_count,
DRM_PLANE_TYPE_PRIMARY, NULL);
if (ret)
return ret;
drm_crtc_helper_add(crtc, &drm_simple_kms_crtc_helper_funcs);
ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
&drm_simple_kms_crtc_funcs, NULL);
if (ret)
return ret;
encoder->possible_crtcs = 1 << drm_crtc_index(crtc);
ret = drm_encoder_init(dev, encoder, &drm_simple_kms_encoder_funcs,
DRM_MODE_ENCODER_NONE, NULL);
if (ret)
return ret;
return drm_mode_connector_attach_encoder(connector, encoder);
}
EXPORT_SYMBOL(drm_simple_display_pipe_init);
MODULE_LICENSE("GPL");

View File

@ -0,0 +1,94 @@
/*
* Copyright (C) 2016 Noralf Trønnes
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __LINUX_DRM_SIMPLE_KMS_HELPER_H
#define __LINUX_DRM_SIMPLE_KMS_HELPER_H
struct drm_simple_display_pipe;
/**
* struct drm_simple_display_pipe_funcs - helper operations for a simple
* display pipeline
*/
struct drm_simple_display_pipe_funcs {
/**
* @enable:
*
* This function should be used to enable the pipeline.
* It is called when the underlying crtc is enabled.
* This hook is optional.
*/
void (*enable)(struct drm_simple_display_pipe *pipe,
struct drm_crtc_state *crtc_state);
/**
* @disable:
*
* This function should be used to disable the pipeline.
* It is called when the underlying crtc is disabled.
* This hook is optional.
*/
void (*disable)(struct drm_simple_display_pipe *pipe);
/**
* @check:
*
* This function is called in the check phase of an atomic update,
* specifically when the underlying plane is checked.
* The simple display pipeline helpers already check that the plane is
* not scaled, fills the entire visible area and is always enabled
* when the crtc is also enabled.
* This hook is optional.
*
* RETURNS:
*
* 0 on success, -EINVAL if the state or the transition can't be
* supported, -ENOMEM on memory allocation failure and -EDEADLK if an
* attempt to obtain another state object ran into a &drm_modeset_lock
* deadlock.
*/
int (*check)(struct drm_simple_display_pipe *pipe,
struct drm_plane_state *plane_state,
struct drm_crtc_state *crtc_state);
/**
* @update:
*
* This function is called when the underlying plane state is updated.
* This hook is optional.
*/
void (*update)(struct drm_simple_display_pipe *pipe,
struct drm_plane_state *plane_state);
};
/**
* struct drm_simple_display_pipe - simple display pipeline
* @crtc: CRTC control structure
* @plane: Plane control structure
* @encoder: Encoder control structure
* @connector: Connector control structure
* @funcs: Pipeline control functions (optional)
*
* Simple display pipeline with plane, crtc and encoder collapsed into one
* entity. It should be initialized by calling drm_simple_display_pipe_init().
*/
struct drm_simple_display_pipe {
struct drm_crtc crtc;
struct drm_plane plane;
struct drm_encoder encoder;
struct drm_connector *connector;
const struct drm_simple_display_pipe_funcs *funcs;
};
int drm_simple_display_pipe_init(struct drm_device *dev,
struct drm_simple_display_pipe *pipe,
const struct drm_simple_display_pipe_funcs *funcs,
const uint32_t *formats, unsigned int format_count,
struct drm_connector *connector);
#endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */