Re: venus: venc: Fix enum frameintervals - was: [GIT PULL for v5.5] Venus updates, take 2

[Mauro Carvalho Chehab <mchehab+samsung@kernel.org>]

Em Wed,  2 Oct 2019 14:29:53 +0300
Stanimir Varbanov <stanimir.varbanov@linaro.org> escreveu:

> Hi Mauro,
> 
> The Venus driver updates include:
> 
> * three fixes: fail to suspend, enum frameinterval issue with encoder
> and frequency table modifications for v3 to handle performance issues.
> * two new features: interconnect bandwidth support on v4 and more precise
> clock-scaling on v4.
> 
> Please pull.
>
> Stanimir Varbanov (3):
>       venus: venc: Fix enum frameintervals

> From c430fca8f2b9b7274a1186f85b69c469378dbd8a Mon Sep 17 00:00:00 2001
> From: Stanimir Varbanov <stanimir.varbanov@linaro.org>
> Date: Tue, 22 Jan 2019 12:53:22 +0200
> Subject: venus: venc: Fix enum frameintervals
> To: Linux Media Mailing List <linux-media@vger.kernel.org>
> Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
> 
> This fixes an issue when setting the encoder framerate because of
> missing precision. Now the frameinterval type is changed to
> TYPE_CONTINUOUS and step = 1. Also the math is changed when
> framerate property is called - the firmware side expects the
> framerate in Q16 values.
> 
> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
> ---
>  drivers/media/platform/qcom/venus/venc.c | 23 ++++++++++++++++-------
>  1 file changed, 16 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c
> index 1b7fb2d5887c..d0a97754ef18 100644
> --- a/drivers/media/platform/qcom/venus/venc.c
> +++ b/drivers/media/platform/qcom/venus/venc.c
> @@ -22,6 +22,7 @@
>  #include "venc.h"
>  
>  #define NUM_B_FRAMES_MAX	4
> +#define FRAMERATE_FACTOR	BIT(16)
>  
>  /*
>   * Three resons to keep MPLANE formats (despite that the number of planes
> @@ -576,7 +577,7 @@ static int venc_enum_frameintervals(struct file *file, void *fh,
>  	struct venus_inst *inst = to_inst(file);
>  	const struct venus_format *fmt;
>  
> -	fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
> +	fival->type = V4L2_FRMIVAL_TYPE_CONTINUOUS;
>  
>  	fmt = find_format(inst, fival->pixel_format,
>  			  V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE);
> @@ -599,12 +600,12 @@ static int venc_enum_frameintervals(struct file *file, void *fh,
>  	    fival->height < frame_height_min(inst))
>  		return -EINVAL;
>  
> -	fival->stepwise.min.numerator = 1;
> -	fival->stepwise.min.denominator = frate_max(inst);
> -	fival->stepwise.max.numerator = 1;
> -	fival->stepwise.max.denominator = frate_min(inst);
> +	fival->stepwise.min.numerator = FRAMERATE_FACTOR;
> +	fival->stepwise.min.denominator = frate_max(inst) * FRAMERATE_FACTOR;
> +	fival->stepwise.max.numerator = FRAMERATE_FACTOR;
> +	fival->stepwise.max.denominator = frate_min(inst) * FRAMERATE_FACTOR;

Hmm... this change seems plain wrong to me... Why do you want to change
the numerator? I mean:

	1/frame_min(inst)

is equal to:

	(const * 1) / (const * frame_min(inst))

Also, on every other driver, the returned fractions are normalized.

>  	fival->stepwise.step.numerator = 1;
> -	fival->stepwise.step.denominator = frate_max(inst);
> +	fival->stepwise.step.denominator = 1;
>  
>  	return 0;
>  }
> @@ -649,6 +650,7 @@ static int venc_set_properties(struct venus_inst *inst)
>  	struct hfi_quantization quant;
>  	struct hfi_quantization_range quant_range;
>  	u32 ptype, rate_control, bitrate, profile = 0, level = 0;
> +	u64 framerate;
>  	int ret;
>  
>  	ret = venus_helper_set_work_mode(inst, VIDC_WORK_MODE_2);
> @@ -659,9 +661,16 @@ static int venc_set_properties(struct venus_inst *inst)
>  	if (ret)
>  		return ret;
>  
> +	framerate = inst->timeperframe.denominator * FRAMERATE_FACTOR;
> +	/* next line is to round up */
> +	framerate += inst->timeperframe.numerator - 1;
> +	do_div(framerate, inst->timeperframe.numerator);
> +
>  	ptype = HFI_PROPERTY_CONFIG_FRAME_RATE;
>  	frate.buffer_type = HFI_BUFFER_OUTPUT;
> -	frate.framerate = inst->fps * (1 << 16);
> +	frate.framerate = framerate;
> +	if (frate.framerate > frate_max(inst) * FRAMERATE_FACTOR)
> +		frate.framerate = frate_max(inst) * FRAMERATE_FACTOR;

You should not assume that userspace will be multiplying by the
frame factor. I mean, the driver should work the same way, no matter
if userspace is setting the framerate as:

	1/30, 2/60, ... n/(n *30)


>  
>  	ret = hfi_session_set_property(inst, ptype, &frate);
>  	if (ret)
> -- 
> 2.21.0
> 




Thanks,
Mauro