linux-kernel - Re: [PATCH v8 01/18] media: ti: j721e-csi2rx: Remove word size alignment on frame width

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <f15d1ac0-5f87-4221-8af3-c0aa5a5b29b2@ideasonboard.com>
Date: Thu, 20 Nov 2025 13:58:40 +0200
From: Tomi Valkeinen <tomi.valkeinen@...asonboard.com>
To: Rishikesh Donadkar <r-donadkar@...com>, jai.luthra@...ux.dev,
 laurent.pinchart@...asonboard.com, mripard@...nel.org
Cc: y-abhilashchandra@...com, devarsht@...com, s-jain1@...com,
 vigneshr@...com, mchehab@...nel.org, robh@...nel.org, krzk+dt@...nel.org,
 p.zabel@...gutronix.de, conor+dt@...nel.org, sakari.ailus@...ux.intel.com,
 hverkuil-cisco@...all.nl, jai.luthra@...asonboard.com,
 changhuang.liang@...rfivetech.com, jack.zhu@...rfivetech.com,
 sjoerd@...labora.com, dan.carpenter@...aro.org, hverkuil+cisco@...nel.org,
 linux-kernel@...r.kernel.org, linux-media@...r.kernel.org,
 devicetree@...r.kernel.org
Subject: Re: [PATCH v8 01/18] media: ti: j721e-csi2rx: Remove word size
 alignment on frame width

Hi,

On 12/11/2025 13:54, 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
> Reviewed-by: Yemike Abhilash Chandra <y-abhilashchandra@...com>
> Signed-off-by: Rishikesh Donadkar <r-donadkar@...com>
> ---
>  .../platform/ti/j721e-csi2rx/j721e-csi2rx.c   | 24 ++++---------------
>  1 file changed, 4 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> index b75aa363d1bf2..710d05a053539 100644
> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> @@ -43,7 +43,6 @@
>  #define SHIM_PSI_CFG0_DST_TAG		GENMASK(31, 16)
>  
>  #define TI_CSI2RX_MAX_PIX_PER_CLK	4
> -#define PSIL_WORD_SIZE_BYTES		16
>  /*
>   * There are no hard limits on the width or height. The DMA engine can handle
>   * all sizes. The max width and height are arbitrary numbers for this driver.
> @@ -250,19 +249,12 @@ static void ti_csi2rx_fill_fmt(const struct ti_csi2rx_fmt *csi_fmt,
>  			       struct v4l2_format *v4l2_fmt)
>  {
>  	struct v4l2_pix_format *pix = &v4l2_fmt->fmt.pix;
> -	unsigned int pixels_in_word;
> -
> -	pixels_in_word = PSIL_WORD_SIZE_BYTES * 8 / csi_fmt->bpp;
>  
>  	/* Clamp width and height to sensible maximums (16K x 16K) */
>  	pix->width = clamp_t(unsigned int, pix->width,
> -			     pixels_in_word,
> -			     MAX_WIDTH_BYTES * 8 / csi_fmt->bpp);
> +			     1, 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 +352,15 @@ 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;

Reviewed-by: Tomi Valkeinen <tomi.valkeinen@...asonboard.com>

 Tomi