The ETHDR is one of the components of the video pipeline on some MediaTek SoCs, such as the MT8188. Two of its sub-blocks are used: the mixer, which is the block's first register window and does the compositing, and the HDR video back-end, which sits on the same data path and is put in bypass since this pipeline does no tone mapping.
Signed-off-by: Julien Stephan <[email protected]> --- drivers/video/mediatek/mtk_ethdr.c | 104 +++++++++++++++++++++++++++++++++++++ drivers/video/mediatek/mtk_ethdr.h | 27 ++++++++++ 2 files changed, 131 insertions(+) diff --git a/drivers/video/mediatek/mtk_ethdr.c b/drivers/video/mediatek/mtk_ethdr.c new file mode 100644 index 00000000000..08ce5fbf518 --- /dev/null +++ b/drivers/video/mediatek/mtk_ethdr.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Mediatek Video ETHDR support + * + * Copyright (c) 2026 BayLibre, SAS. + * Author: Julien Stephan <[email protected]> + */ + +#include <asm/io.h> +#include <dm.h> +#include <errno.h> +#include <linux/bitops.h> + +#include "mtk_disp_comp.h" +#include "mtk_ethdr.h" + +#define MIX_EN 0xc +#define MIX_ROI_SIZE 0x18 +#define MIX_DATAPATH_CON 0x1c +#define OUTPUT_NO_RND BIT(3) +#define SOURCE_RGB_SEL BIT(7) +#define BACKGROUND_RELAY (4 << 9) +#define MIX_ROI_BGCLR 0x20 +#define BGCLR_BLACK 0xff000000 +#define MIX_SRC_CON 0x24 +#define MIX_L_SRC_CON(n) (0x28 + 0x18 * (n)) +#define NON_PREMULTI_SOURCE (2 << 12) +#define MIX_L_SRC_SIZE(n) (0x30 + 0x18 * (n)) +#define MIX_FUNC_DCM0 0x120 +#define MIX_FUNC_DCM1 0x124 +#define MIX_FUNC_DCM_ENABLE 0xffffffff + +/* HDR video back-end registers, in the "vdo_be" register window */ +#define HDR_VDO_BE_0204_VDO_DM_BE 0x204 +#define HDR_VDO_BE_0204_BYPASS_ALL 0x7e + +/* Fields used by this driver but not present in the upstream driver */ +#define MIX_SRC_L2_EN BIT(2) +#define L2_SRC_SEL (2 << 20) +#define L2_OUT_SEL (2 << 22) + +void mtk_ethdr_config(struct udevice *dev, u16 width, u16 height) +{ + struct mtk_ethdr_priv *priv = dev_get_priv(dev); + + /* + * The HDR video back-end sits between the mixer output and the final + * merge, so put it in bypass: this pipeline does no tone mapping. + */ + writel(HDR_VDO_BE_0204_BYPASS_ALL, + priv->vdo_be + HDR_VDO_BE_0204_VDO_DM_BE); + + /* enable internal clocks */ + mtk_disp_comp_write(dev, MIX_FUNC_DCM0, MIX_FUNC_DCM_ENABLE); + mtk_disp_comp_write(dev, MIX_FUNC_DCM1, MIX_FUNC_DCM_ENABLE); + + /* enable mixer */ + mtk_disp_comp_write(dev, MIX_EN, 0x1); + + mtk_disp_comp_write(dev, MIX_ROI_SIZE, (height << 16) | width); + mtk_disp_comp_write(dev, MIX_DATAPATH_CON, + OUTPUT_NO_RND | SOURCE_RGB_SEL | BACKGROUND_RELAY); + mtk_disp_comp_write(dev, MIX_L_SRC_SIZE(2), (height << 16) | width); + mtk_disp_comp_write(dev, MIX_ROI_BGCLR, BGCLR_BLACK); + + /* only configure L2 since only rdma4 and rdma5 are used */ + mtk_disp_comp_write(dev, MIX_L_SRC_CON(2), NON_PREMULTI_SOURCE); + mtk_disp_comp_write(dev, MIX_SRC_CON, + MIX_SRC_L2_EN | L2_SRC_SEL | L2_OUT_SEL); +} + +static int mtk_ethdr_probe(struct udevice *dev) +{ + struct mtk_ethdr_priv *priv = dev_get_priv(dev); + int ret; + + ret = mtk_disp_comp_probe(dev); + if (ret) + return ret; + + priv->vdo_be = dev_remap_addr_name(dev, "vdo_be"); + if (!priv->vdo_be) + return -EINVAL; + + return 0; +} + +static const struct udevice_id mtk_ethdr_ids[] = { + { .compatible = "mediatek,mt8195-disp-ethdr" }, + { } +}; + +/* + * The mixer is the first register window ("mixer" in reg-names) of the + * ethdr block, so binding the ethdr node with default register index 0 + * gives the mixer registers. + */ +U_BOOT_DRIVER(mtk_ethdr) = { + .name = "mtk_ethdr", + .id = UCLASS_MISC, + .of_match = mtk_ethdr_ids, + .probe = mtk_ethdr_probe, + .priv_auto = sizeof(struct mtk_ethdr_priv), +}; diff --git a/drivers/video/mediatek/mtk_ethdr.h b/drivers/video/mediatek/mtk_ethdr.h new file mode 100644 index 00000000000..4a1bae3ddbf --- /dev/null +++ b/drivers/video/mediatek/mtk_ethdr.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Mediatek Video ETHDR support + * + * Copyright (c) 2026 BayLibre, SAS. + * Author: Julien Stephan <[email protected]> + */ + +#ifndef _MTK_ETHDR_H +#define _MTK_ETHDR_H + +#include "mtk_disp_comp.h" + +/* + * @comp must be the first member: the shared component helpers cast the + * private data of every pipeline component to struct mtk_disp_comp_priv. + * @comp holds the "mixer" register window, @vdo_be the HDR video back-end + * one. + */ +struct mtk_ethdr_priv { + struct mtk_disp_comp_priv comp; + void __iomem *vdo_be; +}; + +void mtk_ethdr_config(struct udevice *dev, u16 width, u16 height); + +#endif /* _MTK_ETHDR_H */ -- 2.55.0
