[PATCH 5/8] mmc: dw_mmc: dt-binding: Add tuning related things
heiko at sntech.de
Mon Aug 31 11:24:03 PDT 2015
From: Alexandru M Stan <amstan at chromium.org>
Add ciu_drv, ciu_sample clocks and default-sample-phase. This will later
be used by tuning code.
We do not touch ciu_drive (and by extension define default-drive-phase).
Drive phase is mostly used to define minimum hold times, while one could
write some code to determine what phase meets the minimum hold time
(ex 10 degrees) this will not work with the current clock phase framework
(which floors angles, so we'll get 0 deg, and there's no way to know what
resolution the floors happen at). We assume that the default drive angles
set by the hardware are good enough.
Signed-off-by: Alexandru M Stan <amstan at chromium.org>
Signed-off-by: Heiko Stuebner <heiko at sntech.de>
Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt
index 346c609..5edadc2 100644
@@ -42,11 +42,13 @@ Optional properties:
* clocks: from common clock binding: handle to biu and ciu clocks for the
bus interface unit clock and the card interface unit clock.
-* clock-names: from common clock binding: Shall be "biu" and "ciu".
- If the biu clock is missing we'll simply skip enabling it. If the
- ciu clock is missing we'll just assume that the clock is running at
+* clock-names: from common clock binding: Shall be "biu", "ciu", "ciu_drv" and
+ "ciu_sample". If the biu clock is missing we'll simply skip enabling it.
+ If the ciu clock is missing we'll just assume that the clock is running at
clock-frequency. It is an error to omit both the ciu clock and the
+ clock-frequency. "ciu_drv" and "ciu_sample" are used to control the clock
+ phases, "ciu_sample" is required for tuning high speed modes (if no other
+ custom tuning method is defined).
* clock-frequency: should be the frequency (in Hz) of the ciu clock. If this
is specified and the ciu clock is specified then we'll try to set the ciu
@@ -75,6 +77,10 @@ Optional properties:
* vmmc-supply: The phandle to the regulator to use for vmmc. If this is
specified we'll defer probe until we can find this regulator.
+* default-sample-phase: The default phase to set ciu_sample at probing, low
+ speeds or in case where all phases work at tuning time. If not specified
+ 0 deg will be used.
- All the MSHC controller nodes should be represented in the aliases node using
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