From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH] drm: bridge: dw-hdmi: Fix overflow workaround for Rockchip SoCs Date: Fri, 22 Feb 2019 14:28:14 +0200 Message-ID: <20190222122814.GW3522@pendragon.ideasonboard.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Jonas Karlman Cc: "dri-devel@lists.freedesktop.org" , "linux-rockchip@lists.infradead.org" , Archit Taneja , Andrzej Hajda , David Airlie , Daniel Vetter , Sean Paul , Neil Armstrong , Heiko Stuebner , "linux-kernel@vger.kernel.org" List-Id: linux-rockchip.vger.kernel.org Hi Jonas, Thank you for the patch. On Wed, Feb 20, 2019 at 07:52:31AM +0000, Jonas Karlman wrote: > The Rockchip RK3288 SoC (v2.00a) and RK3328/RK3399 SoCs (v2.11a) have > also been identified as needing this workaround with a single iteration. > > Fixes: be41fc55f1aa ("drm: bridge: dw-hdmi: Handle overflow workaround based on device version") > Signed-off-by: Jonas Karlman This makes me wonder if we have any device at all that doesn't need the workaround... The HDMI encoder in R-Car SoCs doesn't seem to require it, but it reports the same version number as on other SoCs that require the workaround, and enabling it doesn't seem to affect R-Car adversely. Should we thus enable it unconditionally ? Input from Synopsys would be useful. > --- > drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c > index 64c3cf027518..14223c0ee784 100644 > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c > @@ -1655,6 +1655,8 @@ static void dw_hdmi_clear_overflow(struct dw_hdmi *hdmi) > * iteration for others. > * The Amlogic Meson GX SoCs (v2.01a) have been identified as needing > * the workaround with a single iteration. > + * The Rockchip RK3288 SoC (v2.00a) and RK3328/RK3399 SoCs (v2.11a) have > + * been identified as needing the workaround with a single iteration. > */ > > switch (hdmi->version) { > @@ -1663,7 +1665,9 @@ static void dw_hdmi_clear_overflow(struct dw_hdmi *hdmi) > break; > case 0x131a: > case 0x132a: > + case 0x200a: > case 0x201a: > + case 0x211a: > case 0x212a: > count = 1; > break; -- Regards, Laurent Pinchart