The merge block is one of the components of the video pipeline on
some MediaTek SoCs, such as the MT8188. It combines two half-width
inputs into one output.

Signed-off-by: Julien Stephan <[email protected]>
---
 drivers/video/mediatek/mtk_disp_merge_mt8188.c | 106 +++++++++++++++++++++++++
 drivers/video/mediatek/mtk_disp_merge_mt8188.h |  19 +++++
 2 files changed, 125 insertions(+)

diff --git a/drivers/video/mediatek/mtk_disp_merge_mt8188.c 
b/drivers/video/mediatek/mtk_disp_merge_mt8188.c
new file mode 100644
index 00000000000..437bf1a5533
--- /dev/null
+++ b/drivers/video/mediatek/mtk_disp_merge_mt8188.c
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Mediatek Video Disp Merge Support
+ *
+ * Copyright (c) 2025 BayLibre, SAS.
+ * Author: Julien Stephan <[email protected]>
+ */
+
+#include <dm.h>
+
+#include "mtk_disp_comp.h"
+#include "mtk_disp_merge_mt8188.h"
+
+/* MERGE registers */
+#define SUBDISP_DISP_MERGE_ENABLE      0x000
+#define SUBDISP_DISP_MERGE_CFG_0       0x010
+#define SUBDISP_DISP_MERGE_CFG_1       0x014
+#define SUBDISP_DISP_MERGE_CFG_4       0x020
+#define SUBDISP_DISP_MERGE_CFG_10      0x038
+#define SUBDISP_DISP_MERGE_CFG_12      0x040
+#define CFG_10_10_2PI_2PO_BUF_MODE     0x08
+#define CFG_11_10_1PI_2PO_MERGE                0x12
+#define SUBDISP_DISP_MERGE_CFG_24      0x070
+#define SUBDISP_DISP_MERGE_CFG_25      0x074
+#define SUBDISP_DISP_MERGE_CFG_26      0x078
+#define SUBDISP_DISP_MERGE_CFG_27      0x07C
+#define SUBDISP_DISP_MERGE_CFG_30      0x088
+#define SUBDISP_DISP_MERGE_MUTE_0      0xf00
+
+void mtk_disp_merge_config(struct udevice *dev,
+                          u16 width1, u16 height1,
+                          u16 width2, u16 height2,
+                          u16 output_width, u16 output_height)
+{
+       bool dual_input = (width2 != 0 && height2 != 0);
+
+       /* input 1 */
+       if (width1 != 0 && height1 != 0)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_0,
+                                   height1 << 16 | width1);
+
+       /* input 2 */
+       if (dual_input)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_1,
+                                   height2 << 16 | width2);
+
+       /* output */
+       mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_4,
+                           output_height << 16 | output_width);
+
+       /* no pixel/channel swap */
+       mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_10, 0x0);
+
+       if (dual_input)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_12,
+                                   CFG_11_10_1PI_2PO_MERGE);
+       else
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_12,
+                                   CFG_10_10_2PI_2PO_BUF_MODE);
+
+       /* size in sram of inputs 0 and 1 */
+       if (width1 != 0 && height1 != 0)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_24,
+                                   height1 << 16 | width1);
+
+       if (dual_input)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_25,
+                                   height2 << 16 | width2);
+       else
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_25,
+                                   height1 << 16 | width1);
+
+       /* merged size of inputs 0 and 1 */
+       if (width1 != 0 && height1 != 0)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_26,
+                                   height1 << 16 | width1);
+
+       if (dual_input)
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_27,
+                                   height2 << 16 | width2);
+       else
+               mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_27,
+                                   height1 << 16 | width1);
+
+       /* 12 bit lsb off */
+       mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_CFG_30, 0x0);
+
+       /* unmute */
+       mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_MUTE_0, 0x0);
+
+       /* enable */
+       mtk_disp_comp_write(dev, SUBDISP_DISP_MERGE_ENABLE, 0x1);
+}
+
+static const struct udevice_id mtk_disp_merge_ids[] = {
+       { .compatible = "mediatek,mt8188-disp-merge" },
+       {}
+};
+
+U_BOOT_DRIVER(mtk_disp_merge) = {
+       .name      = "mtk_disp_merge",
+       .id        = UCLASS_MISC,
+       .of_match  = mtk_disp_merge_ids,
+       .probe     = mtk_disp_comp_probe,
+       .priv_auto = sizeof(struct mtk_disp_comp_priv),
+};
diff --git a/drivers/video/mediatek/mtk_disp_merge_mt8188.h 
b/drivers/video/mediatek/mtk_disp_merge_mt8188.h
new file mode 100644
index 00000000000..7dd960541a7
--- /dev/null
+++ b/drivers/video/mediatek/mtk_disp_merge_mt8188.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Mediatek Video Disp Merge Support
+ *
+ * Copyright (c) 2025 BayLibre, SAS.
+ * Author: Julien Stephan <[email protected]>
+ */
+
+#ifndef _MTK_DISP_MERGE_MT8188_H
+#define _MTK_DISP_MERGE_MT8188_H
+
+struct udevice;
+
+void mtk_disp_merge_config(struct udevice *dev,
+                          u16 width1, u16 height1,
+                          u16 width2, u16 height2,
+                          u16 output_width, u16 output_height);
+
+#endif

-- 
2.54.0

Reply via email to