Merge tag 'tegra-for-4.2-clk' of git://git.kernel.org/pub/scm/linux/k…

…ernel/git/tegra/linux into clk-next

clk: tegra: Changes for v4.2-rc1

This contains the EMC clock driver that's been exhaustively reviewed and
tested. It also includes a change to the clock core that allows a clock
provider to perform low-level reparenting of clocks. This is required by
the EMC clock driver because the reparenting needs to be done at a very
specific point in time during the EMC frequency switch.

Documentation/devicetree/bindings/clock/nvidia,tegra124-car.txt

@@ -20,15 +20,38 @@ Required properties :
 - #reset-cells : Should be 1.
   In clock consumers, this cell represents the bit number in the CAR's
   array of CLK_RST_CONTROLLER_RST_DEVICES_* registers.
+- nvidia,external-memory-controller : phandle of the EMC driver.
+
+The node should contain a "emc-timings" subnode for each supported RAM type (see
+field RAM_CODE in register PMC_STRAPPING_OPT_A).
+
+Required properties for "emc-timings" nodes :
+- nvidia,ram-code : Should contain the value of RAM_CODE this timing set
+  is used for.
+
+Each "emc-timings" node should contain a "timing" subnode for every supported
+EMC clock rate.
+
+Required properties for "timing" nodes :
+- clock-frequency : Should contain the memory clock rate to which this timing
+relates.
+- nvidia,parent-clock-frequency : Should contain the rate at which the current
+parent of the EMC clock should be running at this timing.
+- clocks : Must contain an entry for each entry in clock-names.
+  See ../clocks/clock-bindings.txt for details.
+- clock-names : Must include the following entries:
+  - emc-parent : the clock that should be the parent of the EMC clock at this
+timing.
 
 Example SoC include file:
 
 / {
-	tegra_car: clock {
+	tegra_car: clock@60006000 {
 		compatible = "nvidia,tegra124-car";
 		reg = <0x60006000 0x1000>;
 		#clock-cells = <1>;
 		#reset-cells = <1>;
+		nvidia,external-memory-controller = <&emc>;
 	};
 
 	usb@c5004000 {
@@ -62,4 +85,23 @@ Example board file:
 	&tegra_car {
 		clocks = <&clk_32k> <&osc>;
 	};
+
+	clock@60006000 {
+		emc-timings-3 {
+			nvidia,ram-code = <3>;
+
+			timing-12750000 {
+				clock-frequency = <12750000>;
+				nvidia,parent-clock-frequency = <408000000>;
+				clocks = <&tegra_car TEGRA124_CLK_PLL_P>;
+				clock-names = "emc-parent";
+			};
+			timing-20400000 {
+				clock-frequency = <20400000>;
+				nvidia,parent-clock-frequency = <408000000>;
+				clocks = <&tegra_car TEGRA124_CLK_PLL_P>;
+				clock-names = "emc-parent";
+			};
+		};
+	};
 };

Documentation/devicetree/bindings/misc/nvidia,tegra20-apbmisc.txt

@@ -10,3 +10,5 @@ Required properties:
        The second entry gives the physical address and length of the
        registers indicating the strapping options.
 
+Optional properties:
+- nvidia,long-ram-code: If present, the RAM code is long (4 bit). If not, short (2 bit).

drivers/clk/Kconfig

@@ -176,3 +176,4 @@ endmenu
 source "drivers/clk/mvebu/Kconfig"
 
 source "drivers/clk/samsung/Kconfig"
+source "drivers/clk/tegra/Kconfig"

drivers/clk/clk.c

@@ -1660,6 +1660,14 @@ static void clk_core_reparent(struct clk_core *core,
 	__clk_recalc_rates(core, POST_RATE_CHANGE);
 }
 
+void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
+{
+	if (!hw)
+		return;
+
+	clk_core_reparent(hw->core, !new_parent ? NULL : new_parent->core);
+}
+
 /**
  * clk_has_parent - check if a clock is a possible parent for another
  * @clk: clock source

drivers/clk/tegra/Kconfig

@@ -0,0 +1,3 @@
+config TEGRA_CLK_EMC
+	def_bool y
+	depends on TEGRA124_EMC

drivers/clk/tegra/Makefile

@@ -11,6 +11,7 @@ obj-y					+= clk-tegra-periph.o
 obj-y					+= clk-tegra-pmc.o
 obj-y					+= clk-tegra-fixed.o
 obj-y					+= clk-tegra-super-gen4.o
+obj-$(CONFIG_TEGRA_CLK_EMC)		+= clk-emc.o
 obj-$(CONFIG_ARCH_TEGRA_2x_SOC)         += clk-tegra20.o
 obj-$(CONFIG_ARCH_TEGRA_3x_SOC)         += clk-tegra30.o
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)	+= clk-tegra114.o