[PATCH v4 4/6] bcm2835: Dynamically calculate bytes per pixel parameter

[Matthias Brugger]

On 10/01/2024 13:29, Ivan T. Ivanov wrote:
> brcm,bcm2708-fb device provided by firmware on RPi5 uses
> 16 bits per pixel, so lets calculate framebuffer bytes
> per pixel dynamically based on queried information.
> 
> Tested to work for RPi2b v1.2, RPi3b v1.3, RPi4b v1.1,
> RPi2 Zero W, RPi5b v1.0.
> 
> Signed-off-by: Ivan T. Ivanov <iivanov at suse.de>

Reviewed-by: Matthias Brugger <mbrugger at suse.com>

> ---
>   drivers/video/bcm2835.c | 18 ++++++++++++++++--
>   1 file changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/video/bcm2835.c b/drivers/video/bcm2835.c
> index 14942526f1..63efa762db 100644
> --- a/drivers/video/bcm2835.c
> +++ b/drivers/video/bcm2835.c
> @@ -16,7 +16,7 @@ static int bcm2835_video_probe(struct udevice *dev)
>   	struct video_uc_plat *plat = dev_get_uclass_plat(dev);
>   	struct video_priv *uc_priv = dev_get_uclass_priv(dev);
>   	int ret;
> -	int w, h, pitch;
> +	int w, h, pitch, bpp;
>   	ulong fb_base, fb_size, fb_start, fb_end;
>   
>   	debug("bcm2835: Query resolution...\n");
> @@ -41,9 +41,23 @@ static int bcm2835_video_probe(struct udevice *dev)
>   					DCACHE_WRITEBACK);
>   	video_set_flush_dcache(dev, true);
>   
> +	bpp = pitch / w;
> +	switch (bpp) {
> +	case 2:
> +		uc_priv->bpix = VIDEO_BPP16;
> +		break;
> +	case 4:
> +		uc_priv->bpix = VIDEO_BPP32;
> +		break;
> +	default:
> +		printf("bcm2835: unexpected bpp %d, pitch %d, width %d\n",
> +		       bpp, pitch, w);
> +		uc_priv->bpix = VIDEO_BPP32;
> +		break;
> +	}
> +
>   	uc_priv->xsize = w;
>   	uc_priv->ysize = h;
> -	uc_priv->bpix = VIDEO_BPP32;
>   	plat->base = fb_base;
>   	plat->size = fb_size;
>