On Thu, Nov 26, 2015 at 10:47:33PM +0900, Chanwoo Choi wrote: > This patch updates the documentation for passive bus devices and adds the > detailed example of Exynos3250. > > Signed-off-by: Chanwoo Choi <cw00.c...@samsung.com> > --- > .../devicetree/bindings/devfreq/exynos-bus.txt | 226 > ++++++++++++++++++++- > 1 file changed, 223 insertions(+), 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > index 5d90623bd173..c4a6fe30075e 100644 > --- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > @@ -12,18 +12,23 @@ SoC has the different sub-blocks. So, this difference > should be specified > in devicetree file instead of each device driver. In result, this driver > is able to support the bus frequency for all Exynos SoCs. > > -Required properties for bus device: > +Required properties for all bus devices: > - compatible: Should be "samsung,exynos-bus". > - clock-names : the name of clock used by the bus, "bus". > - clocks : phandles for clock specified in "clock-names" property. > - #clock-cells: should be 1. > - operating-points-v2: the OPP table including frequency/voltage information > to support DVFS (Dynamic Voltage/Frequency Scaling) feature. > + > +Required properties for only parent bus device: > - vdd-supply: the regulator to provide the buses with the voltage. > - devfreq-events: the devfreq-event device to monitor the curret utilization > of buses. > > -Optional properties for bus device: > +Required properties for only passive bus device: > +- devfreq: the parent bus device. > + > +Optional properties for only parent bus device: > - exynos,saturation-ratio: the percentage value which is used to calibrate > the performance count againt total cycle count. > > @@ -32,7 +37,19 @@ Example1: > power line (regulator). The MIF (Memory Interface) AXI bus is used to > transfer data between DRAM and CPU and uses the VDD_MIF regualtor. > > - - power line(VDD_MIF) --> bus for DMC block (dmc clock) > + - MIF (Memory Interface) block > + : VDD_MIF |--- DMC > + > + - INT (Internal) block > + : VDD_INT |--- LEFTBUS |--- PERIL > + | (parent) |--- MFC > + | |--- G3D > + | > + |--- RIGHTBUS |--- FSYS > + |--- LCD0 > + |--- PERIR > + |--- ISP > + |--- CAM
I would expect the DT to mirror this topology which doesn't seem to be the case in the example. > - MIF bus's frequency/voltage table > ----------------------- > @@ -45,6 +62,20 @@ Example1: > |L5| 400000 |875000 | > ----------------------- > > + - INT bus's frequency/voltage table > + ----------------------------------------------------------------------- > + |Lv| Freq | Voltage | > + ----------------------------------------------------------------------- > + | |LEFTBUS|RIGHTBUS|LCD0 |FSYS |MCUISP |ISP |PERIL |VDD_INT | > + | |*parent|passive |passive|passive|passive|passive|passive| | > + ----------------------------------------------------------------------- > + |L1|50000 |50000 |50000 |50000 |50000 |50000 |50000 |900000 | > + |L2|80000 |80000 |80000 |80000 |80000 |80000 |80000 |900000 | > + |L3|100000 |100000 |100000 |100000 |100000 |100000 |100000 |1000000 | > + |L4|133000 |133000 |133000 |133000 |200000 |200000 | |1000000 | > + |L5|200000 |200000 |200000 |200000 |400000 |300000 | |1000000 | > + ----------------------------------------------------------------------- Do you really have 5 states? It look like there are 2 to me because the OPP tables only really need to have the max freq at each voltage point. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
