| Message ID | 20170607212730.33002-6-s-anna@ti.com |
|---|---|
| State | Accepted |
| Commit | 32a04832a120b8ddc6b8752d30ba4be00fa23b74 |
| Headers | show |
| Series | [1/6] ARM: dts: omap44xx-clocks: Set IVA DPLL and its output clock rates | expand |
diff --git a/arch/arm/boot/dts/dra7xx-clocks.dtsi b/arch/arm/boot/dts/dra7xx-clocks.dtsi index 8a82490035d9..76e2b7478141 100644 --- a/arch/arm/boot/dts/dra7xx-clocks.dtsi +++ b/arch/arm/boot/dts/dra7xx-clocks.dtsi @@ -376,6 +376,8 @@ compatible = "ti,omap4-dpll-clock"; clocks = <&sys_clkin1>, <&dpll_iva_byp_mux>; reg = <0x01a0>, <0x01a4>, <0x01ac>, <0x01a8>; + assigned-clocks = <&dpll_iva_ck>; + assigned-clock-rates = <1165000000>; }; dpll_iva_m2_ck: dpll_iva_m2_ck@1b0 { @@ -387,6 +389,8 @@ reg = <0x01b0>; ti,index-starts-at-one; ti,invert-autoidle-bit; + assigned-clocks = <&dpll_iva_m2_ck>; + assigned-clock-rates = <388333334>; }; iva_dclk: iva_dclk {
The IVA DPLL in DRA7xx provides the output clocks for only the IVAHD subsystem in DRA7xx as compared to previous OMAP generations when it provided the clocks for both DSP and IVAHD subsystems. This DPLL is currently not configured by older bootloaders. Use the DT standard properties "assigned-clocks" and "assigned-clock-rates" to set the IVA DPLL clock rate and the rates for its derivative clocks at boot time to properly initialize/lock this DPLL and be independent of the bootloader version. Newer u-boots (from 2017.01 onwards) reuse and can update these properties to choose an appropriate one-time fixed OPP configuration. The DPLL will automatically transition into a low-power stop mode when the associated output clocks are not utilized or gated automatically. The reset value of the divider M2 (that supplies the IVA_GFLCK, the functional clock for the IVAHD subsystem) does not match a specific OPP. So, the derived output clock from this IVA DPLL has to be initialized as well to avoid initializing these divider outputs to an incorrect frequencies. The OPP_NOM clock frequencies are defined in the AM572x SR2.0 Data Sheet vB, section 5.5.2 "Voltage And Core Clock Specifications". The clock rates are chosen based on these OPP_NOM values and defined as per a DRA7xx PLL spec document. The DPLL locked frequency is 2300 MHz, so the dpll_iva_ck clock rate used is half of this value. The value for the divider clock, dpll_iva_m2_ck, has to be set to 388.333334 MHz or more for the divider clk logic to compute the appropriate divider value for OPP_NOM. Signed-off-by: Suman Anna <s-anna@ti.com> --- arch/arm/boot/dts/dra7xx-clocks.dtsi | 4 ++++ 1 file changed, 4 insertions(+) -- 2.12.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html