linux-kernel - Re: [PATCH RESEND] drm/meson: remove firmware framebuffers

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Date:   Wed, 12 Dec 2018 10:55:34 +0100
From:   Neil Armstrong <narmstrong@...libre.com>
To:     Maxime Jourdan <mjourdan@...libre.com>
Cc:     linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-amlogic@...ts.infradead.org, dri-devel@...ts.freedesktop.org
Subject: Re: [PATCH RESEND] drm/meson: remove firmware framebuffers

Hi Maxime,

On 10/12/2018 10:28, Maxime Jourdan wrote:
> In case we are using simplefb or another conflicting framebuffer, make
> the call to drm_fb_helper_remove_conflicting_framebuffers()
> 
> Signed-off-by: Maxime Jourdan <mjourdan@...libre.com>
> ---
>  drivers/gpu/drm/meson/meson_drv.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
> index d3443125e661..afbb3d707d15 100644
> --- a/drivers/gpu/drm/meson/meson_drv.c
> +++ b/drivers/gpu/drm/meson/meson_drv.c
> @@ -159,6 +159,23 @@ static void meson_vpu_init(struct meson_drm *priv)
>  	writel_relaxed(0x20000, priv->io_base + _REG(VPU_WRARB_MODE_L2C1));
>  }
>  
> +static void meson_remove_framebuffers(void)
> +{
> +	struct apertures_struct *ap;
> +
> +	ap = alloc_apertures(1);
> +	if (!ap)
> +		return;
> +
> +	/* The framebuffer can be located anywhere in RAM */
> +	ap->ranges[0].base = 0;
> +	ap->ranges[0].size = ~0;
> +
> +	drm_fb_helper_remove_conflicting_framebuffers(ap, "meson-drm-fb",
> +						      false);

I always wondered, where does the "meson-drm-fb" comes from ???

Neil

> +	kfree(ap);
> +}
> +
>  static int meson_drv_bind_master(struct device *dev, bool has_components)
>  {
>  	struct platform_device *pdev = to_platform_device(dev);
> @@ -242,6 +259,9 @@ static int meson_drv_bind_master(struct device *dev, bool has_components)
>  	if (ret)
>  		goto free_drm;
>  
> +	/* Remove early framebuffers (ie. simplefb) */
> +	meson_remove_framebuffers();
> +
>  	drm_mode_config_init(drm);
>  	drm->mode_config.max_width = 3840;
>  	drm->mode_config.max_height = 2160;
>