[PATCH] ARM64: dts: meson: reduce odroid-c2 eMMC maximum rate

[PATCH] ARM64: dts: meson: reduce odroid-c2 eMMC maximum rate

[Jerome Brunet]

Different modules maybe installed by the user on the eMMC connector
of the odroid-c2. While the red modules are working without an issue,
it seems some black modules (apparently Samsung based) are having
issue at 200MHz

While the tuning algorithm introduced in v4.14 enables high speed modes
on every other tested designs, it seems a problem remains for this
particular combination of board and eMMC module.

Lowering the maximum frequency of the eMMC on this board until we can
figure out a better solution.

Fixes: d341ca88eead ("mmc: meson-gx: rework tuning function")
Suggested-by: Ellie Reeves <ellierevves@gmail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts b/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts
index 73a030a5ecf3..43475139576c 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts
@@ -311,7 +311,7 @@
 	pinctrl-names = "default", "clk-gate";
 
 	bus-width = <8>;
-	max-frequency = <200000000>;
+	max-frequency = <100000000>;
 	non-removable;
 	disable-wp;
 	cap-mmc-highspeed;
-- 
2.14.3

[PATCH] ARM64: dts: meson: reduce odroid-c2 eMMC maximum rate

[Kevin Hilman]

Jerome Brunet <jbrunet@baylibre.com> writes:

> Different modules maybe installed by the user on the eMMC connector
> of the odroid-c2. While the red modules are working without an issue,
> it seems some black modules (apparently Samsung based) are having
> issue at 200MHz
>
> While the tuning algorithm introduced in v4.14 enables high speed modes
> on every other tested designs, it seems a problem remains for this
> particular combination of board and eMMC module.
>
> Lowering the maximum frequency of the eMMC on this board until we can
> figure out a better solution.
>
> Fixes: d341ca88eead ("mmc: meson-gx: rework tuning function")
> Suggested-by: Ellie Reeves <ellierevves@gmail.com>
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

Applied to v4.17/dt64 and Cc'd to stable,

Kevin

[PATCH] ARM64: dts: meson: reduce odroid-c2 eMMC maximum rate

[Kevin Hilman]

On Fri, Mar 2, 2018 at 5:44 AM, Jerome Brunet <jbrunet@baylibre.com> wrote:
> Different modules maybe installed by the user on the eMMC connector
> of the odroid-c2. While the red modules are working without an issue,
> it seems some black modules (apparently Samsung based) are having
> issue at 200MHz
>
> While the tuning algorithm introduced in v4.14 enables high speed modes
> on every other tested designs, it seems a problem remains for this
> particular combination of board and eMMC module.
>
> Lowering the maximum frequency of the eMMC on this board until we can
> figure out a better solution.
>
> Fixes: d341ca88eead ("mmc: meson-gx: rework tuning function")
> Suggested-by: Ellie Reeves <ellierevves@gmail.com>
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

Now in mainline as commit c04ffa71ff49 upstream.

The mainline patch has "Cc: stable at vger.kernel.org", but it doesn't
seem to have appeared in stable yet, and I've verified that it applies
cleanly to linux-4.15.y and linux-4.14.y.

Kevin


> ---
>  arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts b/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts
> index 73a030a5ecf3..43475139576c 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts
> +++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts
> @@ -311,7 +311,7 @@
>         pinctrl-names = "default", "clk-gate";
>
>         bus-width = <8>;
> -       max-frequency = <200000000>;
> +       max-frequency = <100000000>;
>         non-removable;
>         disable-wp;
>         cap-mmc-highspeed;
> --
> 2.14.3
>

[PATCH] ARM64: dts: meson: reduce odroid-c2 eMMC maximum rate

[Greg KH]

On Mon, Mar 26, 2018 at 01:23:44PM -0700, Kevin Hilman wrote:
> On Fri, Mar 2, 2018 at 5:44 AM, Jerome Brunet <jbrunet@baylibre.com> wrote:
> > Different modules maybe installed by the user on the eMMC connector
> > of the odroid-c2. While the red modules are working without an issue,
> > it seems some black modules (apparently Samsung based) are having
> > issue at 200MHz
> >
> > While the tuning algorithm introduced in v4.14 enables high speed modes
> > on every other tested designs, it seems a problem remains for this
> > particular combination of board and eMMC module.
> >
> > Lowering the maximum frequency of the eMMC on this board until we can
> > figure out a better solution.
> >
> > Fixes: d341ca88eead ("mmc: meson-gx: rework tuning function")
> > Suggested-by: Ellie Reeves <ellierevves@gmail.com>
> > Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
> 
> Now in mainline as commit c04ffa71ff49 upstream.

Really?  I do not see it in Linus's tree, are you sure about that?

$ git show c04ffa71ff49
fatal: ambiguous argument 'c04ffa71ff49': unknown revision or path not in the working tree.

thanks,

greg k-h

[PATCH] ARM64: dts: meson: reduce odroid-c2 eMMC maximum rate

[Kevin Hilman]

Greg KH <gregkh@linuxfoundation.org> writes:

> On Mon, Mar 26, 2018 at 01:23:44PM -0700, Kevin Hilman wrote:
>> On Fri, Mar 2, 2018 at 5:44 AM, Jerome Brunet <jbrunet@baylibre.com> wrote:
>> > Different modules maybe installed by the user on the eMMC connector
>> > of the odroid-c2. While the red modules are working without an issue,
>> > it seems some black modules (apparently Samsung based) are having
>> > issue at 200MHz
>> >
>> > While the tuning algorithm introduced in v4.14 enables high speed modes
>> > on every other tested designs, it seems a problem remains for this
>> > particular combination of board and eMMC module.
>> >
>> > Lowering the maximum frequency of the eMMC on this board until we can
>> > figure out a better solution.
>> >
>> > Fixes: d341ca88eead ("mmc: meson-gx: rework tuning function")
>> > Suggested-by: Ellie Reeves <ellierevves@gmail.com>
>> > Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
>> 
>> Now in mainline as commit c04ffa71ff49 upstream.
>
> Really?  I do not see it in Linus's tree, are you sure about that?
>
> $ git show c04ffa71ff49
> fatal: ambiguous argument 'c04ffa71ff49': unknown revision or path not in the working tree.

Oops, you're right.  It's still in arm-soc, not yet in mainline.  Sorry
for the noise.

Kevin