[PATCH v2 4/4] clk: dt: Introduce always-on clock domain documentation

@@ -0,0 +1,35 @@
+Always-on Clock Domain
+
+Some hardware is contains bunches of clocks which must never be
+turned off.  If drivers a) fail to obtain a reference to any of
+these or b) give up a previously obtained reference during suspend,
+the common clk framework will attempt to disable them and the
+hardware can fail irrecoverably.  Usually, the only way to recover
+from these failures is to restart.
+
+To avoid either of these two scenarios from catastrophically
+disabling an otherwise perfectly healthy running system, we have
+implemented a clock domain where clocks are consumed and references
+are taken, thus preventing them from being shut down by the
+framework.
+
+We use the generic clock bindings found in:
+  Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : Must be "always-on-clk-domain"
+
+Example:
+
+clk-domain {
+	compatible = "always-on-clk-domain";
+	clocks = <&clk_s_c0_flexgen CLK_EXT2F_A9>,
+		 <&clk_s_c0_flexgen CLK_COMPO_DVP>,
+		 <&clk_s_c0_flexgen CLK_MMC_1>,
+		 <&clk_s_c0_flexgen CLK_ICN_SBC>,
+		 <&clk_s_c0_flexgen CLK_ICN_LMI>,
+		 <&clk_s_c0_flexgen CLK_ICN_CPU>,
+		 <&clk_s_c0_flexgen CLK_TX_ICN_DMU>,
+		 <&clk_s_a0_flexgen CLK_IC_LMI0>,
+		 <&clk_m_a9>;
+};