[PATCH v6 13/14] drm/mediatek: Support CRC in OVL

CK Hu (胡俊光) ck.hu at mediatek.com
Mon Mar 25 23:11:56 PDT 2024


Hi, Shawn:

On Fri, 2024-03-22 at 13:28 +0800, Shawn Sung wrote:
> From: Hsiao Chien Sung <shawn.sung at mediatek.com>
> 
> We choose OVL as the CRC generator from other hardware
> components that are also capable of calculating CRCs,
> since its frame done event triggers vblanks, it can be
> used as a signal to know when is safe to retrieve CRC of
> the frame.
> 
> Please note that position of the hardware component
> that is chosen as CRC generator in the display path is
> significant. For example, while OVL is the first module
> in VDOSYS0, its CRC won't be affected by the modules
> after it, which means effects applied by PQ, Gamma,
> Dither or any other components after OVL won't be
> calculated in CRC generation.
> 
> Signed-off-by: Hsiao Chien Sung <shawn.sung at mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_ddp_comp.c |   3 +
>  drivers/gpu/drm/mediatek/mtk_disp_drv.h |   3 +
>  drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 198
> ++++++++++++++++++++++--
>  3 files changed, 194 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> index 17b0364112922..cb71effda9c2a 100644
> --- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
> @@ -351,6 +351,9 @@ static const struct mtk_ddp_comp_funcs ddp_ovl =
> {
>  	.clk_enable = mtk_ovl_clk_enable,
>  	.clk_disable = mtk_ovl_clk_disable,
>  	.config = mtk_ovl_config,
> +	.crc_cnt = mtk_ovl_crc_cnt,
> +	.crc_entry = mtk_ovl_crc_entry,
> +	.crc_read = mtk_ovl_crc_read,
>  	.start = mtk_ovl_start,
>  	.stop = mtk_ovl_stop,
>  	.register_vblank_cb = mtk_ovl_register_vblank_cb,
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> index 082ac18fe04aa..c476056a5cbb5 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> @@ -105,6 +105,9 @@ void mtk_ovl_enable_vblank(struct device *dev);
>  void mtk_ovl_disable_vblank(struct device *dev);
>  const u32 *mtk_ovl_get_formats(struct device *dev);
>  size_t mtk_ovl_get_num_formats(struct device *dev);
> +size_t mtk_ovl_crc_cnt(struct device *dev);
> +u32 *mtk_ovl_crc_entry(struct device *dev);
> +void mtk_ovl_crc_read(struct device *dev);
>  
>  void mtk_ovl_adaptor_add_comp(struct device *dev, struct mtk_mutex
> *mutex);
>  void mtk_ovl_adaptor_remove_comp(struct device *dev, struct
> mtk_mutex *mutex);
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> index a936f338ab79d..279e6193e7975 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> @@ -24,12 +24,20 @@
>  #define OVL_FME_CPL_INT					BIT(1)
>  #define DISP_REG_OVL_INTSTA			0x0008
>  #define DISP_REG_OVL_EN				0x000c
> +#define OVL_EN						BIT(0)
> +#define OVL_OP_8BIT_MODE				BIT(4)
> +#define OVL_HG_FOVL_CK_ON				BIT(8)
> +#define OVL_HF_FOVL_CK_ON				BIT(10)
> +#define DISP_REG_OVL_TRIG			0x0010
> +#define OVL_CRC_EN					BIT(8)
> +#define OVL_CRC_CLR					BIT(9)
>  #define DISP_REG_OVL_RST			0x0014
>  #define DISP_REG_OVL_ROI_SIZE			0x0020
>  #define DISP_REG_OVL_DATAPATH_CON		0x0024
>  #define OVL_LAYER_SMI_ID_EN				BIT(0)
>  #define OVL_BGCLR_SEL_IN				BIT(2)
>  #define OVL_LAYER_AFBC_EN(n)				BIT(4+n)
> +#define OVL_OUTPUT_CLAMP				BIT(26)
>  #define DISP_REG_OVL_ROI_BGCLR			0x0028
>  #define DISP_REG_OVL_SRC_CON			0x002c
>  #define DISP_REG_OVL_CON(n)			(0x0030 + 0x20 * (n))
> @@ -42,7 +50,26 @@
>  #define DISP_REG_OVL_RDMA_CTRL(n)		(0x00c0 + 0x20 * (n))
>  #define DISP_REG_OVL_RDMA_GMC(n)		(0x00c8 + 0x20 * (n))
>  #define DISP_REG_OVL_ADDR_MT2701		0x0040
> +#define DISP_REG_OVL_CRC			0x0270
> +#define OVL_CRC_OUT_MASK				GENMASK(30, 0)
>  #define DISP_REG_OVL_CLRFMT_EXT			0x02D0
> +#define DISP_REG_OVL_CLRFMT_EXT1		0x02D8
> +#define OVL_CLRFMT_EXT1_CSC_EN(n)			(1 << (((n) *
> 4) + 1))
> +#define DISP_REG_OVL_Y2R_PARA_R0(n)		(0x0134 + 0x28 * (n))
> +#define OVL_Y2R_PARA_C_CF_RMY				(GENMAS
> K(14, 0))
> +#define DISP_REG_OVL_Y2R_PARA_G0(n)		(0x013c + 0x28 * (n))
> +#define OVL_Y2R_PARA_C_CF_GMU				(GENMAS
> K(30, 16))
> +#define DISP_REG_OVL_Y2R_PARA_B1(n)		(0x0148 + 0x28 * (n))
> +#define OVL_Y2R_PARA_C_CF_BMV				(GENMAS
> K(14, 0))
> +#define DISP_REG_OVL_Y2R_PARA_YUV_A_0(n)	(0x014c + 0x28 * (n))
> +#define OVL_Y2R_PARA_C_CF_YA				(GENMASK(10,
> 0))
> +#define OVL_Y2R_PARA_C_CF_UA				(GENMASK(26,
> 16))
> +#define DISP_REG_OVL_Y2R_PARA_YUV_A_1(n)	(0x0150 + 0x28 * (n))
> +#define OVL_Y2R_PARA_C_CF_VA				(GENMASK(10,
> 0))
> +#define DISP_REG_OVL_Y2R_PRE_ADD2(n)		(0x0154 + 0x28 * (n))
> +#define DISP_REG_OVL_R2R_R0(n)			(0x0500 + 0x40
> * (n))
> +#define DISP_REG_OVL_R2R_G1(n)			(0x0510 + 0x40
> * (n))
> +#define DISP_REG_OVL_R2R_B2(n)			(0x0520 + 0x40
> * (n))
>  #define DISP_REG_OVL_ADDR_MT8173		0x0f40
>  #define DISP_REG_OVL_ADDR(ovl, n)		((ovl)->data->addr +
> 0x20 * (n))
>  #define DISP_REG_OVL_HDR_ADDR(ovl, n)		((ovl)->data-
> >addr + 0x20 * (n) + 0x04)
> @@ -55,6 +82,8 @@
>  #define OVL_CON_CLRFMT_MAN	BIT(23)
>  #define OVL_CON_BYTE_SWAP	BIT(24)
>  #define OVL_CON_RGB_SWAP	BIT(25)
> +#define OVL_CON_MTX_AUTO_DIS	BIT(26)
> +#define OVL_CON_MTX_EN		BIT(27)
>  #define OVL_CON_CLRFMT_RGB	(1 << 12)
>  #define OVL_CON_CLRFMT_RGBA8888	(2 << 12)
>  #define OVL_CON_CLRFMT_ARGB8888	(3 << 12)
> @@ -62,6 +91,7 @@
>  #define OVL_CON_CLRFMT_YUYV	(5 << 12)
>  #define OVL_CON_MTX_YUV_TO_RGB	(6 << 16)
>  #define OVL_CON_CLRFMT_PARGB8888	(OVL_CON_CLRFMT_ARGB8888 |
> OVL_CON_CLRFMT_MAN)
> +#define OVL_CON_MTX_PROGRAMMABLE	(8 << 16)
>  #define OVL_CON_CLRFMT_RGB565(ovl)	((ovl)->data->fmt_rgb565_is_0 ?
> \
>  					0 : OVL_CON_CLRFMT_RGB)
>  #define OVL_CON_CLRFMT_RGB888(ovl)	((ovl)->data->fmt_rgb565_is_0 ?
> \
> @@ -131,6 +161,10 @@ static const u32 mt8195_formats[] = {
>  	DRM_FORMAT_YUYV,
>  };
>  
> +static const u32 mt8195_ovl_crc_ofs[] = {
> +	DISP_REG_OVL_CRC,
> +};
> +
>  struct mtk_disp_ovl_data {
>  	unsigned int addr;
>  	unsigned int gmc_bits;
> @@ -141,12 +175,15 @@ struct mtk_disp_ovl_data {
>  	const u32 *formats;
>  	size_t num_formats;
>  	bool supports_clrfmt_ext;
> +	const u32 *crc_ofs;
> +	size_t crc_cnt;
>  };
>  
>  /*
>   * struct mtk_disp_ovl - DISP_OVL driver structure
>   * @crtc: associated crtc to report vblank events to
>   * @data: platform data
> + * @crc: crc related information
>   */
>  struct mtk_disp_ovl {
>  	struct drm_crtc			*crtc;
> @@ -156,8 +193,31 @@ struct mtk_disp_ovl {
>  	const struct mtk_disp_ovl_data	*data;
>  	void				(*vblank_cb)(void *data);
>  	void				*vblank_cb_data;
> +	resource_size_t			regs_pa;
> +	struct mtk_crtc_crc		crc;
>  };
>  
> +size_t mtk_ovl_crc_cnt(struct device *dev)
> +{
> +	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
> +
> +	return ovl->crc.cnt;
> +}
> +
> +u32 *mtk_ovl_crc_entry(struct device *dev)
> +{
> +	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
> +
> +	return ovl->crc.va;
> +}
> +
> +void mtk_ovl_crc_read(struct device *dev)
> +{
> +	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
> +
> +	mtk_crtc_read_crc(&ovl->crc, ovl->regs);
> +}
> +
>  static irqreturn_t mtk_disp_ovl_irq_handler(int irq, void *dev_id)
>  {
>  	struct mtk_disp_ovl *priv = dev_id;
> @@ -237,21 +297,40 @@ void mtk_ovl_clk_disable(struct device *dev)
>  void mtk_ovl_start(struct device *dev)
>  {
>  	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
> +	unsigned int reg = readl(ovl->regs +
> DISP_REG_OVL_DATAPATH_CON);
>  
> -	if (ovl->data->smi_id_en) {
> -		unsigned int reg;
> +	if (ovl->data->smi_id_en)
> +		reg |= OVL_LAYER_SMI_ID_EN;
>  
> -		reg = readl(ovl->regs + DISP_REG_OVL_DATAPATH_CON);
> -		reg = reg | OVL_LAYER_SMI_ID_EN;
> -		writel_relaxed(reg, ovl->regs +
> DISP_REG_OVL_DATAPATH_CON);
> +	/*
> +	 * When doing Y2R conversion, it's common to get an output
> +	 * that is larger than 10 bits (negative numbers).
> +	 * Enable this bit to clamp the output to 10 bits per channel
> +	 * (should always be enabled)
> +	 */
> +	reg |= OVL_OUTPUT_CLAMP;
> +	writel_relaxed(reg, ovl->regs + DISP_REG_OVL_DATAPATH_CON);
> +
> +	reg = OVL_EN;
> +	if (ovl->data->crc_cnt) {
> +		/* enable crc  and its related clocks */
> +		writel_relaxed(OVL_CRC_EN, ovl->regs +
> DISP_REG_OVL_TRIG);
> +		reg |= OVL_OP_8BIT_MODE | OVL_HG_FOVL_CK_ON |
> OVL_HF_FOVL_CK_ON;
>  	}
> -	writel_relaxed(0x1, ovl->regs + DISP_REG_OVL_EN);
> +	writel_relaxed(reg, ovl->regs + DISP_REG_OVL_EN);
> +
> +#if IS_REACHABLE(CONFIG_MTK_CMDQ)
> +	mtk_crtc_start_crc_cmdq(&ovl->crc);
> +#endif
>  }
>  
>  void mtk_ovl_stop(struct device *dev)
>  {
>  	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
>  
> +#if IS_REACHABLE(CONFIG_MTK_CMDQ)
> +	mtk_crtc_stop_crc_cmdq(&ovl->crc);
> +#endif
>  	writel_relaxed(0x0, ovl->regs + DISP_REG_OVL_EN);
>  	if (ovl->data->smi_id_en) {
>  		unsigned int reg;
> @@ -488,6 +567,83 @@ void mtk_ovl_layer_config(struct device *dev,
> unsigned int idx,
>  	    (state->base.fb && !state->base.fb->format->has_alpha))
>  		ignore_pixel_alpha = OVL_CONST_BLEND;
>  
> +	/*
> +	 * OVL only supports 8 bits data in CRC calculation, transform
> 10-bit
> +	 * RGB to 8-bit RGB by leveraging the ability of the Y2R (YUV-
> to-RGB)
> +	 * hardware to multiply coefficients, although there is nothing
> to do
> +	 * with the YUV format.
> +	 */
> +	if (ovl->data->supports_clrfmt_ext) {
> +		u32 y2r_coef = 0, y2r_offset = 0, r2r_coef = 0, csc_en
> = 0;
> +
> +		if (is_10bit_rgb(fmt)) {
> +			con |= OVL_CON_MTX_AUTO_DIS | OVL_CON_MTX_EN |
> OVL_CON_MTX_PROGRAMMABLE;
> +
> +			/*
> +			 * Y2R coefficient setting
> +			 * bit 13 is 2^1, bit 12 is 2^0, bit 11 is 2^-
> 1,
> +			 * bit 10 is 2^-2 = 0.25
> +			 */
> +			y2r_coef = BIT(10);
> +
> +			/* -1 in 10bit */
> +			y2r_offset = GENMASK(10, 0) - 1;

I don't know why do this? If an input value is 0x100, then

0x100 right shit 2 bit become 0x40.
0x40 - 1 = 0x3f.
0x3f left shift 2 bit become 0xfc.

So input 0x100 and output 0xfc. Why?

> +
> +			/*
> +			 * R2R coefficient setting
> +			 * bit 19 is 2^1, bit 18 is 2^0, bit 17 is 2^-
> 1,
> +			 * bit 20 is 2^2 = 4
> +			 */
> +			r2r_coef = BIT(20);
> +
> +			/* CSC_EN is for R2R */
> +			csc_en = OVL_CLRFMT_EXT1_CSC_EN(idx);
> +
> +			/*
> +			 * 1. YUV input data - 1 and shift right for 2
> bits to remove it
> +			 * [R']   [0.25    0    0]   [Y in - 1]
> +			 * [G'] = [   0 0.25    0] * [U in - 1]
> +			 * [B']   [   0    0 0.25]   [V in - 1]
> +			 *
> +			 * 2. shift left for 2 bit letting the last 2
> bits become 0

You truncate the last two bit, so some quality lost. I think the
quality is main function and CRC is just for debug. So it's better that
in normal case we keep quality and only for debug to lost the quality.

I have another question. You just truncate the last two bit but it is
still 10 bit value, so CRC could calculate this 10 bit value? I don't
know why you say CRC just for 8 bit?

Regards,
CK

> +			 * [R out]   [ 4  0  0]   [R']
> +			 * [G out] = [ 0  4  0] * [G']
> +			 * [B out]   [ 0  0  4]   [B']
> +			 */
> +		}
> +
> +		mtk_ddp_write_mask(cmdq_pkt, y2r_coef,
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_Y2R_PARA_R0(idx),
> +				   OVL_Y2R_PARA_C_CF_RMY);
> +		mtk_ddp_write_mask(cmdq_pkt, (y2r_coef << 16),
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_Y2R_PARA_G0(idx),
> +				   OVL_Y2R_PARA_C_CF_GMU);
> +		mtk_ddp_write_mask(cmdq_pkt, y2r_coef,
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_Y2R_PARA_B1(idx),
> +				   OVL_Y2R_PARA_C_CF_BMV);
> +
> +		mtk_ddp_write_mask(cmdq_pkt, y2r_offset,
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_Y2R_PARA_YUV_A_0(idx),
> +				   OVL_Y2R_PARA_C_CF_YA);
> +		mtk_ddp_write_mask(cmdq_pkt, (y2r_offset << 16),
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_Y2R_PARA_YUV_A_0(idx),
> +				   OVL_Y2R_PARA_C_CF_UA);
> +		mtk_ddp_write_mask(cmdq_pkt, y2r_offset,
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_Y2R_PARA_YUV_A_1(idx),
> +				   OVL_Y2R_PARA_C_CF_VA);
> +
> +		mtk_ddp_write_relaxed(cmdq_pkt, r2r_coef,
> +				      &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_R2R_R0(idx));
> +		mtk_ddp_write_relaxed(cmdq_pkt, r2r_coef,
> +				      &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_R2R_G1(idx));
> +		mtk_ddp_write_relaxed(cmdq_pkt, r2r_coef,
> +				      &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_R2R_B2(idx));
> +
> +		mtk_ddp_write_mask(cmdq_pkt, csc_en,
> +				   &ovl->cmdq_reg, ovl->regs,
> DISP_REG_OVL_CLRFMT_EXT1,
> +				   OVL_CLRFMT_EXT1_CSC_EN(idx));
> +	}
> +
>  	if (pending->rotation & DRM_MODE_REFLECT_Y) {
>  		con |= OVL_CON_VIRT_FLIP;
>  		addr += (pending->height - 1) * pending->pitch;
> @@ -594,15 +750,31 @@ static int mtk_disp_ovl_probe(struct
> platform_device *pdev)
>  		dev_err(dev, "failed to ioremap ovl\n");
>  		return PTR_ERR(priv->regs);
>  	}
> +
> +	priv->data = of_device_get_match_data(dev);
> +	platform_set_drvdata(pdev, priv);
> +
> +	if (priv->data->crc_cnt) {
> +		mtk_crtc_init_crc(&priv->crc,
> +				  priv->data->crc_ofs, priv->data-
> >crc_cnt,
> +				  DISP_REG_OVL_TRIG, OVL_CRC_CLR);
> +	}
> +
>  #if IS_REACHABLE(CONFIG_MTK_CMDQ)
>  	ret = cmdq_dev_get_client_reg(dev, &priv->cmdq_reg, 0);
>  	if (ret)
>  		dev_dbg(dev, "get mediatek,gce-client-reg fail!\n");
> -#endif
> -
> -	priv->data = of_device_get_match_data(dev);
> -	platform_set_drvdata(pdev, priv);
>  
> +	if (priv->data->crc_cnt) {
> +		if (of_property_read_u32_index(dev->of_node,
> +					       "mediatek,gce-events",
> 0,
> +					       &priv->crc.cmdq_event))
> {
> +			dev_warn(dev, "failed to get gce-events for
> crc\n");
> +		}
> +		priv->crc.cmdq_reg = &priv->cmdq_reg;
> +		mtk_crtc_create_crc_cmdq(dev, &priv->crc);
> +	}
> +#endif
>  	ret = devm_request_irq(dev, irq, mtk_disp_ovl_irq_handler,
>  			       IRQF_TRIGGER_NONE, dev_name(dev), priv);
>  	if (ret < 0) {
> @@ -623,6 +795,10 @@ static int mtk_disp_ovl_probe(struct
> platform_device *pdev)
>  
>  static void mtk_disp_ovl_remove(struct platform_device *pdev)
>  {
> +	struct device *dev = &pdev->dev;
> +	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
> +
> +	mtk_crtc_destroy_crc(&ovl->crc);
>  	component_del(&pdev->dev, &mtk_disp_ovl_component_ops);
>  	pm_runtime_disable(&pdev->dev);
>  }
> @@ -693,6 +869,8 @@ static const struct mtk_disp_ovl_data
> mt8195_ovl_driver_data = {
>  	.formats = mt8195_formats,
>  	.num_formats = ARRAY_SIZE(mt8195_formats),
>  	.supports_clrfmt_ext = true,
> +	.crc_ofs = mt8195_ovl_crc_ofs,
> +	.crc_cnt = ARRAY_SIZE(mt8195_ovl_crc_ofs),
>  };
>  
>  static const struct of_device_id mtk_disp_ovl_driver_dt_match[] = {


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