On Sat, Apr 23, 2016 at 12:33:51PM -0500, Andy Gross wrote: > On Sat, Apr 23, 2016 at 11:56:50AM -0500, Rob Herring wrote: > > On Fri, Apr 22, 2016 at 5:17 PM, Andy Gross <andy.gross@xxxxxxxxxx> wrote: > > > This patch adds the device tree support for the Qualcomm SCM firmware. > > > > > > Signed-off-by: Andy Gross <andy.gross@xxxxxxxxxx> > > > --- > > > .../devicetree/bindings/firmware/qcom,scm.txt | 31 ++++++++++++++++++++++ > > > 1 file changed, 31 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/firmware/qcom,scm.txt > > > > > > diff --git a/Documentation/devicetree/bindings/firmware/qcom,scm.txt b/Documentation/devicetree/bindings/firmware/qcom,scm.txt > > > new file mode 100644 > > > index 0000000..57b9b3a > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/firmware/qcom,scm.txt > > > @@ -0,0 +1,31 @@ > > > +QCOM Secure Channel Manager (SCM) > > > + > > > +Qualcomm processors include an interface to communicate to the secure firmware. > > > +This interface allows for clients to request different types of actions. These > > > +can include CPU power up/down, HDCP requests, loading of firmware, and other > > > +assorted actions. > > > + > > > +Required properties: > > > +- compatible: must contain one of the following: > > > + * "qcom,scm-apq8064" for APQ8064 > > > + * "qcom,scm-apq8084" for MSM8084 > > > + * "qcom,scm-msm8916" for MSM8916 > > > + * "qcom,scm-msm8974" for MSM8974 > > > +- clocks: One to three clocks may be required based on compatible. > > > + * Only core clock required for "qcom,scm-apq8064" > > > + * Core, iface, and bus clocks required for all other compatibles. > > > +- clock-names: Must contain "core" for the core clock, "iface" for the interface > > > + clock and "bus" for the bus clock per the requirements of the compatible. > > > + > > > +Example for MSM8916: > > > + > > > + firmware { > > > + compatible = "simple-bus"; > > > > Firmware is a bus? Really? Let's not put hacks in the DT just so you > > get automatic probing. > > So something like: > > firmware { > compatible = "qcom,scm-apq8084"; > clocks = <&gcc GCC_CE1_CLK> , <&gcc GCC_CE1_AXI_CLK>, <&gcc GCC_CE1_AHB_CLK>; > clock-names = "core", "bus", "iface"; > }; > > Seems to work fine. Yes, because the top level nodes are probed. But then you can't have any other firmware nodes. You are going to have to call of_platform_populate on the /firmware node or create the device yourself. If there are other users of /firmware needing to probe, then we can perhaps do it generically. > > > + > > > + scm { > > > + compatible = "qcom,scm-msm8916"; > > > + clocks = <&gcc GCC_CRYPTO_CLK> , <&gcc GCC_CRYPTO_AXI_CLK>, <&gcc GCC_CRYPTO_AHB_CLK>; > > > + clock-names = "core", "bus", "iface"; > > > > Generally, /firmware defines an interface to firmware. I don't think > > clocks belong here. This implies that non-secure world can turn off > > clocks to secure world? > > The caller into the SCM is on the hook for making sure the clocks are turned on. > The firmware people decided to not manage the clocks. In a perfect world, they > would turn on their own clocks and it would all be self contained. Sadly, it > isn't going to change. Okay. Seems like a security problem to me though. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html