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[PATCH v5 01/14] media: ti: j721e-csi2rx: Remove word size alignment on frame width

Rishikesh Donadkar posted 14 patches 5 months, 2 weeks ago
There is a newer version of this series
[PATCH v5 01/14] media: ti: j721e-csi2rx: Remove word size alignment on frame width
Posted by Rishikesh Donadkar 5 months, 2 weeks ago 
j721e-csi2rx driver has a limitation of frame width being a multiple
word size. However, there is no such limitation imposed by the
hardware [1].

Remove this limitation from the driver.

Link: https://www.ti.com/lit/pdf/spruj16
Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
---
 .../platform/ti/j721e-csi2rx/j721e-csi2rx.c     | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
index 3992f8b754b7..b3a27f4c3210 100644
--- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
+++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
@@ -260,9 +260,6 @@ static void ti_csi2rx_fill_fmt(const struct ti_csi2rx_fmt *csi_fmt,
 			     MAX_WIDTH_BYTES * 8 / csi_fmt->bpp);
 	pix->height = clamp_t(unsigned int, pix->height, 1, MAX_HEIGHT_LINES);
 
-	/* Width should be a multiple of transfer word-size */
-	pix->width = rounddown(pix->width, pixels_in_word);
-
 	v4l2_fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	pix->pixelformat = csi_fmt->fourcc;
 	pix->bytesperline = pix->width * (csi_fmt->bpp / 8);
@@ -360,23 +357,15 @@ static int ti_csi2rx_enum_framesizes(struct file *file, void *fh,
 				     struct v4l2_frmsizeenum *fsize)
 {
 	const struct ti_csi2rx_fmt *fmt;
-	unsigned int pixels_in_word;
 
 	fmt = find_format_by_fourcc(fsize->pixel_format);
 	if (!fmt || fsize->index != 0)
 		return -EINVAL;
 
-	/*
-	 * Number of pixels in one PSI-L word. The transfer happens in multiples
-	 * of PSI-L word sizes.
-	 */
-	pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / fmt->bpp;
-
 	fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
-	fsize->stepwise.min_width = pixels_in_word;
-	fsize->stepwise.max_width = rounddown(MAX_WIDTH_BYTES * 8 / fmt->bpp,
-					      pixels_in_word);
-	fsize->stepwise.step_width = pixels_in_word;
+	fsize->stepwise.min_width = 1;
+	fsize->stepwise.max_width = MAX_WIDTH_BYTES * 8 / fmt->bpp;
+	fsize->stepwise.step_width = 1;
 	fsize->stepwise.min_height = 1;
 	fsize->stepwise.max_height = MAX_HEIGHT_LINES;
 	fsize->stepwise.step_height = 1;
-- 
2.34.1
Re: [PATCH v5 01/14] media: ti: j721e-csi2rx: Remove word size alignment on frame width
Posted by Jai Luthra 5 months, 1 week ago 
Hi Rishikesh,

Quoting Rishikesh Donadkar (2025-08-25 19:55:09)
> j721e-csi2rx driver has a limitation of frame width being a multiple
> word size. However, there is no such limitation imposed by the
> hardware [1].

Is there no limitation for the step size, or also not limitation for the
minimum size of transfer?

> 
> Remove this limitation from the driver.
> 
> Link: https://www.ti.com/lit/pdf/spruj16
> Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
> ---
>  .../platform/ti/j721e-csi2rx/j721e-csi2rx.c     | 17 +++--------------
>  1 file changed, 3 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> index 3992f8b754b7..b3a27f4c3210 100644
> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> @@ -260,9 +260,6 @@ static void ti_csi2rx_fill_fmt(const struct ti_csi2rx_fmt *csi_fmt,
>                              MAX_WIDTH_BYTES * 8 / csi_fmt->bpp);

Here the pix->width is restricted to be at minimum pixels_in_word.
So TRY_FMT/S_FMT with a width = 1 will be clamped by the driver.

>         pix->height = clamp_t(unsigned int, pix->height, 1, MAX_HEIGHT_LINES);
>  
> -       /* Width should be a multiple of transfer word-size */
> -       pix->width = rounddown(pix->width, pixels_in_word);
> -
>         v4l2_fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
>         pix->pixelformat = csi_fmt->fourcc;
>         pix->bytesperline = pix->width * (csi_fmt->bpp / 8);
> @@ -360,23 +357,15 @@ static int ti_csi2rx_enum_framesizes(struct file *file, void *fh,
>                                      struct v4l2_frmsizeenum *fsize)
>  {
>         const struct ti_csi2rx_fmt *fmt;
> -       unsigned int pixels_in_word;
>  
>         fmt = find_format_by_fourcc(fsize->pixel_format);
>         if (!fmt || fsize->index != 0)
>                 return -EINVAL;
>  
> -       /*
> -        * Number of pixels in one PSI-L word. The transfer happens in multiples
> -        * of PSI-L word sizes.
> -        */
> -       pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / fmt->bpp;
> -
>         fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> -       fsize->stepwise.min_width = pixels_in_word;
> -       fsize->stepwise.max_width = rounddown(MAX_WIDTH_BYTES * 8 / fmt->bpp,
> -                                             pixels_in_word);
> -       fsize->stepwise.step_width = pixels_in_word;
> +       fsize->stepwise.min_width = 1;

But here, in ENUM_FRAMESIZES we allow width to go as low as 1.

Can you make sure both of them match whatever is correct (and possible by
the hardware)?

> +       fsize->stepwise.max_width = MAX_WIDTH_BYTES * 8 / fmt->bpp;
> +       fsize->stepwise.step_width = 1;
>         fsize->stepwise.min_height = 1;
>         fsize->stepwise.max_height = MAX_HEIGHT_LINES;
>         fsize->stepwise.step_height = 1;
> -- 
> 2.34.1
> 

Thanks,
    Jai
Re: [PATCH v5 01/14] media: ti: j721e-csi2rx: Remove word size alignment on frame width
Posted by Rishikesh Donadkar 5 months ago 
On 05/09/25 16:37, Jai Luthra wrote:
> Hi Rishikesh,


Hi Jai,

Thank you for the comments


>
> Quoting Rishikesh Donadkar (2025-08-25 19:55:09)
>> j721e-csi2rx driver has a limitation of frame width being a multiple
>> word size. However, there is no such limitation imposed by the
>> hardware [1].
> Is there no limitation for the step size, or also not limitation for the
> minimum size of transfer?



I did not see any mention of restrictions on the step size and minimum 
size of transfer in the TRM and the CSI functional specifications.


>
>> Remove this limitation from the driver.
>>
>> Link: https://www.ti.com/lit/pdf/spruj16
>> Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
>> ---
>>   .../platform/ti/j721e-csi2rx/j721e-csi2rx.c     | 17 +++--------------
>>   1 file changed, 3 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
>> index 3992f8b754b7..b3a27f4c3210 100644
>> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
>> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
>> @@ -260,9 +260,6 @@ static void ti_csi2rx_fill_fmt(const struct ti_csi2rx_fmt *csi_fmt,
>>                               MAX_WIDTH_BYTES * 8 / csi_fmt->bpp);
> Here the pix->width is restricted to be at minimum pixels_in_word.
> So TRY_FMT/S_FMT with a width = 1 will be clamped by the driver.
>
>>          pix->height = clamp_t(unsigned int, pix->height, 1, MAX_HEIGHT_LINES);
>>   
>> -       /* Width should be a multiple of transfer word-size */
>> -       pix->width = rounddown(pix->width, pixels_in_word);
>> -
>>          v4l2_fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
>>          pix->pixelformat = csi_fmt->fourcc;
>>          pix->bytesperline = pix->width * (csi_fmt->bpp / 8);
>> @@ -360,23 +357,15 @@ static int ti_csi2rx_enum_framesizes(struct file *file, void *fh,
>>                                       struct v4l2_frmsizeenum *fsize)
>>   {
>>          const struct ti_csi2rx_fmt *fmt;
>> -       unsigned int pixels_in_word;
>>   
>>          fmt = find_format_by_fourcc(fsize->pixel_format);
>>          if (!fmt || fsize->index != 0)
>>                  return -EINVAL;
>>   
>> -       /*
>> -        * Number of pixels in one PSI-L word. The transfer happens in multiples
>> -        * of PSI-L word sizes.
>> -        */
>> -       pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / fmt->bpp;
>> -
>>          fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
>> -       fsize->stepwise.min_width = pixels_in_word;
>> -       fsize->stepwise.max_width = rounddown(MAX_WIDTH_BYTES * 8 / fmt->bpp,
>> -                                             pixels_in_word);
>> -       fsize->stepwise.step_width = pixels_in_word;
>> +       fsize->stepwise.min_width = 1;
> But here, in ENUM_FRAMESIZES we allow width to go as low as 1.
>
> Can you make sure both of them match whatever is correct (and possible by
> the hardware)?


Sure


>
>> +       fsize->stepwise.max_width = MAX_WIDTH_BYTES * 8 / fmt->bpp;
>> +       fsize->stepwise.step_width = 1;
>>          fsize->stepwise.min_height = 1;
>>          fsize->stepwise.max_height = MAX_HEIGHT_LINES;
>>          fsize->stepwise.step_height = 1;
>> -- 
>> 2.34.1
>>
> Thanks,
>      Jai


Regards,

Rishikesh
Re: [PATCH v5 01/14] media: ti: j721e-csi2rx: Remove word size alignment on frame width
Posted by Yemike Abhilash Chandra 5 months, 1 week ago 
Hi Rishikesh,

Thanks for the patches.

On 25/08/25 19:55, Rishikesh Donadkar wrote:
> j721e-csi2rx driver has a limitation of frame width being a multiple
> word size. However, there is no such limitation imposed by the
> hardware [1].
> 
> Remove this limitation from the driver.
> 
> Link: https://www.ti.com/lit/pdf/spruj16
> Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
> ---

Reviewed-by: Yemike Abhilash Chandra <y-abhilashchandra@ti.com>

>   .../platform/ti/j721e-csi2rx/j721e-csi2rx.c     | 17 +++--------------
>   1 file changed, 3 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> index 3992f8b754b7..b3a27f4c3210 100644
> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> @@ -260,9 +260,6 @@ static void ti_csi2rx_fill_fmt(const struct ti_csi2rx_fmt *csi_fmt,
>   			     MAX_WIDTH_BYTES * 8 / csi_fmt->bpp);
>   	pix->height = clamp_t(unsigned int, pix->height, 1, MAX_HEIGHT_LINES);
>   
> -	/* Width should be a multiple of transfer word-size */
> -	pix->width = rounddown(pix->width, pixels_in_word);
> -
>   	v4l2_fmt->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
>   	pix->pixelformat = csi_fmt->fourcc;
>   	pix->bytesperline = pix->width * (csi_fmt->bpp / 8);
> @@ -360,23 +357,15 @@ static int ti_csi2rx_enum_framesizes(struct file *file, void *fh,
>   				     struct v4l2_frmsizeenum *fsize)
>   {
>   	const struct ti_csi2rx_fmt *fmt;
> -	unsigned int pixels_in_word;
>   
>   	fmt = find_format_by_fourcc(fsize->pixel_format);
>   	if (!fmt || fsize->index != 0)
>   		return -EINVAL;
>   
> -	/*
> -	 * Number of pixels in one PSI-L word. The transfer happens in multiples
> -	 * of PSI-L word sizes.
> -	 */
> -	pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / fmt->bpp;
> -
>   	fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> -	fsize->stepwise.min_width = pixels_in_word;
> -	fsize->stepwise.max_width = rounddown(MAX_WIDTH_BYTES * 8 / fmt->bpp,
> -					      pixels_in_word);
> -	fsize->stepwise.step_width = pixels_in_word;
> +	fsize->stepwise.min_width = 1;
> +	fsize->stepwise.max_width = MAX_WIDTH_BYTES * 8 / fmt->bpp;
> +	fsize->stepwise.step_width = 1;
>   	fsize->stepwise.min_height = 1;
>   	fsize->stepwise.max_height = MAX_HEIGHT_LINES;
>   	fsize->stepwise.step_height = 1;

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