On Wed, Oct 23, 2019 at 1:39 PM Tony Lindgren <tony@xxxxxxxxxxx> wrote:
>
> Looks like omap3 RNG is similar to the omap2 rng, let's get it working
> by configring the dts node for it.
Thank you for doing this. This really helps reduce the startup delays
while waiting for entropy.
>
> We must also add rng_ick to core_l4_clkdm as noted by Adam Ford.
>
> And please note that the RNG is likely disabled on HS devices. At least
> n900 does not have it accessible, and instead omap3-rom-rng driver must
> be used. So let's tag RNG as disabled on n900 as noted by Pali Rohár
> <pali.rohar@xxxxxxxxx>.
>
> On am3517 at least the clocks need to be configured to get it working
> as noted by Adam Ford, so let's tag it disabled for now.
>
Tested-by: Adam Ford <aford173@xxxxxxxxx> #logicpd-torpedo-37xx-devkit
> Cc: Aaro Koskinen <aaro.koskinen@xxxxxx>
> Cc: Adam Ford <aford173@xxxxxxxxx>
> Cc: Pali Rohár <pali.rohar@xxxxxxxxx>
> Cc: Sebastian Reichel <sre@xxxxxxxxxx>
> Cc: Tero Kristo <t-kristo@xxxxxx>
> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
> ---
>
> Sorry for the delay on getting this posted, please test.
>
> ---
> arch/arm/boot/dts/am3517.dtsi | 6 +++++
> arch/arm/boot/dts/omap3-n900.dts | 5 ++++
> arch/arm/boot/dts/omap3.dtsi | 25 +++++++++++++++++++
> .../boot/dts/omap34xx-omap36xx-clocks.dtsi | 2 +-
> 4 files changed, 37 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/am3517.dtsi b/arch/arm/boot/dts/am3517.dtsi
> --- a/arch/arm/boot/dts/am3517.dtsi
> +++ b/arch/arm/boot/dts/am3517.dtsi
> @@ -115,6 +115,12 @@
> };
> };
>
> +/* Not currently working, probably needs at least different clocks */
> +&rng_target {
> + status = "disabled";
> + /delete-property/ clocks;
> +};
> +
> /* Table Table 5-79 of the TRM shows 480ab000 is reserved */
> &usb_otg_hs {
> status = "disabled";
> diff --git a/arch/arm/boot/dts/omap3-n900.dts b/arch/arm/boot/dts/omap3-n900.dts
> --- a/arch/arm/boot/dts/omap3-n900.dts
> +++ b/arch/arm/boot/dts/omap3-n900.dts
> @@ -1013,6 +1013,11 @@
> };
> };
>
> +/* RNG not directly accessible on n900, se omap3-rom-rng instead */
> +&rng_target {
> + status = "disabled";
> +};
> +
> &usb_otg_hs {
> interface-type = <0>;
> usb-phy = <&usb2_phy>;
> diff --git a/arch/arm/boot/dts/omap3.dtsi b/arch/arm/boot/dts/omap3.dtsi
> --- a/arch/arm/boot/dts/omap3.dtsi
> +++ b/arch/arm/boot/dts/omap3.dtsi
> @@ -8,6 +8,7 @@
> * kind, whether express or implied.
> */
>
> +#include <dt-bindings/bus/ti-sysc.h>
> #include <dt-bindings/gpio/gpio.h>
> #include <dt-bindings/interrupt-controller/irq.h>
> #include <dt-bindings/pinctrl/omap.h>
> @@ -502,6 +503,30 @@
> status = "disabled";
> };
>
> + /* Likely needs to be tagged disabled on HS devices */
> + rng_target: target-module@480a0000 {
> + compatible = "ti,sysc-omap2", "ti,sysc";
> + reg = <0x480a003c 0x4>,
> + <0x480a0040 0x4>,
> + <0x480a0044 0x4>;
> + reg-names = "rev", "sysc", "syss";
> + ti,sysc-mask = <(SYSC_OMAP2_AUTOIDLE)>;
> + ti,sysc-sidle = <SYSC_IDLE_FORCE>,
> + <SYSC_IDLE_NO>;
> + ti,syss-mask = <1>;
> + clocks = <&rng_ick>;
> + clock-names = "ick";
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges = <0 0x480a0000 0x2000>;
> +
> + rng: rng@0 {
> + compatible = "ti,omap2-rng";
> + reg = <0x0 0x2000>;
> + interrupts = <52>;
> + };
> + };
> +
> mcbsp2: mcbsp@49022000 {
> compatible = "ti,omap3-mcbsp";
> reg = <0x49022000 0xff>,
> diff --git a/arch/arm/boot/dts/omap34xx-omap36xx-clocks.dtsi b/arch/arm/boot/dts/omap34xx-omap36xx-clocks.dtsi
> --- a/arch/arm/boot/dts/omap34xx-omap36xx-clocks.dtsi
> +++ b/arch/arm/boot/dts/omap34xx-omap36xx-clocks.dtsi
> @@ -260,6 +260,6 @@
> <&gpt10_ick>, <&mcbsp5_ick>, <&mcbsp1_ick>,
> <&omapctrl_ick>, <&aes2_ick>, <&sha12_ick>, <&icr_ick>,
> <&des2_ick>, <&mspro_ick>, <&mailboxes_ick>,
> - <&mspro_fck>;
> + <&rng_ick>, <&mspro_fck>;
> };
> };
> --
> 2.23.0
