drivers/gpu/drm/exynos/exynos_drm_plane.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/exynos/exynos_drm_plane.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/exynos/exynos_drm_plane.c
Extension
.c
Size
9457 bytes
Lines
337
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2011 Samsung Electronics Co.Ltd
 * Authors: Joonyoung Shim <jy0922.shim@samsung.com>
 */


#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_blend.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_print.h>
#include <drm/exynos_drm.h>

#include "exynos_drm_crtc.h"
#include "exynos_drm_drv.h"
#include "exynos_drm_fb.h"
#include "exynos_drm_gem.h"
#include "exynos_drm_plane.h"

/*
 * This function is to get X or Y size shown via screen. This needs length and
 * start position of CRTC.
 *
 *      <--- length --->
 * CRTC ----------------
 *      ^ start        ^ end
 *
 * There are six cases from a to f.
 *
 *             <----- SCREEN ----->
 *             0                 last
 *   ----------|------------------|----------
 * CRTCs
 * a -------
 *        b -------
 *        c --------------------------
 *                 d --------
 *                           e -------
 *                                  f -------
 */
static int exynos_plane_get_size(int start, unsigned length, unsigned last)
{
	int end = start + length;
	int size = 0;

	if (start <= 0) {
		if (end > 0)
			size = min_t(unsigned, end, last);
	} else if (start <= last) {
		size = min_t(unsigned, last - start, length);
	}

	return size;
}

static void exynos_plane_mode_set(struct exynos_drm_plane_state *exynos_state)
{
	struct drm_plane_state *state = &exynos_state->base;
	struct drm_crtc *crtc = state->crtc;
	struct drm_crtc_state *crtc_state =
		drm_atomic_get_new_crtc_state(state->state, crtc);
	struct drm_display_mode *mode = &crtc_state->adjusted_mode;
	int crtc_x, crtc_y;
	unsigned int crtc_w, crtc_h;
	unsigned int src_x, src_y;
	unsigned int src_w, src_h;
	unsigned int actual_w;
	unsigned int actual_h;

	/*
	 * The original src/dest coordinates are stored in exynos_state->base,
	 * but we want to keep another copy internal to our driver that we can
	 * clip/modify ourselves.
	 */

	crtc_x = state->crtc_x;
	crtc_y = state->crtc_y;
	crtc_w = state->crtc_w;
	crtc_h = state->crtc_h;

	src_x = state->src_x >> 16;
	src_y = state->src_y >> 16;
	src_w = state->src_w >> 16;
	src_h = state->src_h >> 16;

	/* set ratio */
	exynos_state->h_ratio = (src_w << 16) / crtc_w;
	exynos_state->v_ratio = (src_h << 16) / crtc_h;

Annotation

Implementation Notes