[PATCH v5 07/39] ARM: dts: imx6qdl-sabrelite: remove erratum ERR006687 workaround

On 03/10/2017 11:17 AM, Fabio Estevam wrote:

On Fri, Mar 10, 2017 at 3:59 PM, Troy Kisky
[off-list ref] wrote:

quoted

On 3/9/2017 8:52 PM, Steve Longerbeam wrote:

quoted

There is a pin conflict with GPIO_6. This pin functions as a power
input pin to the OV5642 camera sensor, but ENET uses it as the h/w
workaround for erratum ERR006687, to wake-up the ARM cores on normal
RX and TX packet done events. So we need to remove the h/w workaround
to support the OV5642. The result is that the CPUidle driver will no
longer allow entering the deep idle states on the sabrelite.

This is a partial revert of

commit 6261c4c8f13e ("ARM: dts: imx6qdl-sabrelite: use GPIO_6 for FEC
                      interrupt.")
commit a28eeb43ee57 ("ARM: dts: imx6: tag boards that have the HW workaround
                      for ERR006687")

Signed-off-by: Steve Longerbeam <redacted>
---
 arch/arm/boot/dts/imx6qdl-sabrelite.dtsi | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi b/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi
index 8413179..89dce27 100644
--- a/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi

@@ -270,9 +270,6 @@
      txd1-skew-ps = <0>;
      txd2-skew-ps = <0>;
      txd3-skew-ps = <0>;

How about

+#if !IS_ENABLED(CONFIG_VIDEO_OV5642)

Or maybe just create a new device tree for using the camera, like
imx6q-sabrelite-camera.dts.

This way we can keep the FEC erratum for the existing sabrelite dtb's.

Is it really necessary to keep the erratum in sabrelite dts? Because the
sabrelite is a _reference_ platform, vendors use this dts as a working
example of how to configure their imx6-based hardware. So as a working
example, it should contain as much example hardware config as possible
as a guide. If a vendor does not require OV5642 support and requires
the lower power consumption that the erratum workaround provides, they
can refer to other example imx6 dts files which still implement the
erratum, or look at the git log of this file.

Steve