Re: [Patch 05/35] media: ti-vpe: Use line average de-interlacing for first 2 frames

[Benoit Parrot <bparrot@ti.com>]

Hans Verkuil <hverkuil@xs4all.nl> wrote on Mon [2016-Oct-17 16:14:35 +0200]:
> On 09/28/2016 11:20 PM, Benoit Parrot wrote:
> > From: Archit Taneja <archit@ti.com>
> > 
> > For n input fields, the VPE de-interlacer creates n - 2 progressive frames.
> 
> That's confusing. I think you mean '(n / 2) - 1'? Two fields make one frame, right?

No it is (N - 2), the motion detection block requires 3 fields to create the motion
vector data. So without doing anything special the first progressive frame would be
generated after the 3 field is consumed and then a progressive frame is generated
every field after that always keeping the last 2 fields in reserve.

This patch adds a special modes so that line averaging mode is use for the
first two fields so that in the end we get N progressive frames generated
from N fields.

Benoit

> 
> Regards,
> 
> 	Hans
> 
> > 
> > To support this, we use line average mode of de-interlacer for the first 2
> > input fields to generate 2 progressive frames. We then revert back to the
> > preferred EDI method, and create n - 2 frames, creating a sum of n frames.
> > 
> > Signed-off-by: Archit Taneja <archit@ti.com>
> > Signed-off-by: Nikhil Devshatwar <nikhil.nd@ti.com>
> > Signed-off-by: Benoit Parrot <bparrot@ti.com>
> > ---
> >  drivers/media/platform/ti-vpe/vpe.c | 33 +++++++++++++++++++++++++++++++--
> >  1 file changed, 31 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/media/platform/ti-vpe/vpe.c b/drivers/media/platform/ti-vpe/vpe.c
> > index 3921fd8cdf1d..a0b29685fb69 100644
> > --- a/drivers/media/platform/ti-vpe/vpe.c
> > +++ b/drivers/media/platform/ti-vpe/vpe.c
> > @@ -141,7 +141,7 @@ struct vpe_dei_regs {
> >   */
> >  static const struct vpe_dei_regs dei_regs = {
> >  	.mdt_spacial_freq_thr_reg = 0x020C0804u,
> > -	.edi_config_reg = 0x0118100Fu,
> > +	.edi_config_reg = 0x0118100Cu,
> >  	.edi_lut_reg0 = 0x08040200u,
> >  	.edi_lut_reg1 = 0x1010100Cu,
> >  	.edi_lut_reg2 = 0x10101010u,
> > @@ -798,6 +798,23 @@ static void set_dei_shadow_registers(struct vpe_ctx *ctx)
> >  	ctx->load_mmrs = true;
> >  }
> >  
> > +static void config_edi_input_mode(struct vpe_ctx *ctx, int mode)
> > +{
> > +	struct vpe_mmr_adb *mmr_adb = ctx->mmr_adb.addr;
> > +	u32 *edi_config_reg = &mmr_adb->dei_regs[3];
> > +
> > +	if (mode & 0x2)
> > +		write_field(edi_config_reg, 1, 1, 2);	/* EDI_ENABLE_3D */
> > +
> > +	if (mode & 0x3)
> > +		write_field(edi_config_reg, 1, 1, 3);	/* EDI_CHROMA_3D  */
> > +
> > +	write_field(edi_config_reg, mode, VPE_EDI_INP_MODE_MASK,
> > +		VPE_EDI_INP_MODE_SHIFT);
> > +
> > +	ctx->load_mmrs = true;
> > +}
> > +
> >  /*
> >   * Set the shadow registers whose values are modified when either the
> >   * source or destination format is changed.
> > @@ -1111,6 +1128,15 @@ static void device_run(void *priv)
> >  	ctx->dst_vb = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> >  	WARN_ON(ctx->dst_vb == NULL);
> >  
> > +	if (ctx->deinterlacing) {
> > +		/*
> > +		 * we have output the first 2 frames through line average, we
> > +		 * now switch to EDI de-interlacer
> > +		 */
> > +		if (ctx->sequence == 2)
> > +			config_edi_input_mode(ctx, 0x3); /* EDI (Y + UV) */
> > +	}
> > +
> >  	/* config descriptors */
> >  	if (ctx->dev->loaded_mmrs != ctx->mmr_adb.dma_addr || ctx->load_mmrs) {
> >  		vpdma_map_desc_buf(ctx->dev->vpdma, &ctx->mmr_adb);
> > @@ -1865,7 +1891,10 @@ static void vpe_buf_queue(struct vb2_buffer *vb)
> >  
> >  static int vpe_start_streaming(struct vb2_queue *q, unsigned int count)
> >  {
> > -	/* currently we do nothing here */
> > +	struct vpe_ctx *ctx = vb2_get_drv_priv(q);
> > +
> > +	if (ctx->deinterlacing)
> > +		config_edi_input_mode(ctx, 0x0);
> >  
> >  	return 0;
> >  }
> >