From d9273547c2d4f0d79a3d22324dfc0e125754e6e0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= Date: Sun, 13 Sep 2015 17:17:14 +0200 Subject: [PATCH 181/203] BCM270X_DT: mz61581: Set txbuflen to 32k MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Because of the spi dma mapping/engine overhead with spi-bcm2835, txbuflen has to be increased from 4096 to 32768 to maximize throughput (11MB/s at 128MHz). Signed-off-by: Noralf Trønnes --- arch/arm/boot/dts/overlays/README | 2 ++ arch/arm/boot/dts/overlays/mz61581-overlay.dts | 2 ++ 2 files changed, 4 insertions(+) --- a/arch/arm/boot/dts/overlays/README +++ b/arch/arm/boot/dts/overlays/README @@ -368,6 +368,8 @@ Params: speed Display fps Delay between frame updates + txbuflen Transmit buffer length (default 32768) + debug Debug output level {0-7} xohms Touchpanel sensitivity (X-plate resistance) --- a/arch/arm/boot/dts/overlays/mz61581-overlay.dts +++ b/arch/arm/boot/dts/overlays/mz61581-overlay.dts @@ -57,6 +57,7 @@ bgr; fps = <30>; buswidth = <8>; + txbuflen = <32768>; reset-gpios = <&gpio 15 0>; dc-gpios = <&gpio 25 0>; @@ -103,6 +104,7 @@ speed = <&mz61581>, "spi-max-frequency:0"; rotate = <&mz61581>, "rotate:0"; fps = <&mz61581>, "fps:0"; + txbuflen = <&mz61581>, "txbuflen:0"; debug = <&mz61581>, "debug:0"; xohms = <&mz61581_ts>,"ti,x-plate-ohms;0"; };