[PATCH] drm/arm/hdlcd: Take over EFI framebuffer properly

[Thomas Zimmermann]

Hi

Am 14.06.22 um 15:04 schrieb Robin Murphy:
> The Arm Juno board EDK2 port has provided an EFI GOP display via HDLCD0
> for some time now, which works nicely as an early framebuffer. However,
> once the HDLCD driver probes and takes over the hardware, it should
> take over the logical framebuffer as well, otherwise the now-defunct GOP
> device hangs about and virtual console output inevitably disappears into
> the wrong place most of the time.
> 
> Signed-off-by: Robin Murphy <robin.murphy at arm.com>
> ---
>   drivers/gpu/drm/arm/hdlcd_drv.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c
> index af59077a5481..a5d04884658b 100644
> --- a/drivers/gpu/drm/arm/hdlcd_drv.c
> +++ b/drivers/gpu/drm/arm/hdlcd_drv.c
> @@ -331,6 +331,8 @@ static int hdlcd_drm_bind(struct device *dev)
>   		goto err_vblank;
>   	}
>   
> +	drm_fb_helper_remove_conflicting_framebuffers(NULL, "hdlcd", false);
> +

In addition to what Javier said, it appears to be too late to call this 
function. If anything her etouches hardware, you might accidentally 
interfere with the EFI-related driver. Rather call it at the top of 
ldlcd_drm_bind().

Best regards
Thomas

>   	drm_mode_config_reset(drm);
>   	drm_kms_helper_poll_init(drm);
>   

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
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