ARM: tegra: Implement clk_m

On currently supported SoCs, clk_m always runs at the same frequency as
the oscillator input. However newer SoC generations such as Tegra210 no
longer have that restriction. Prepare for that by separating clk_m from
the oscillator clock and allow SoC code to override the clk_m rate.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/include/asm/arch-tegra20/clock-tables.h b/arch/arm/include/asm/arch-tegra20/clock-tables.h
index 894be08..812e876 100644
--- a/arch/arm/include/asm/arch-tegra20/clock-tables.h
+++ b/arch/arm/include/asm/arch-tegra20/clock-tables.h
@@ -29,6 +29,7 @@
 	/* These are the base clocks (inputs to the Tegra SOC) */
 	CLOCK_ID_32KHZ,
 	CLOCK_ID_OSC,
+	CLOCK_ID_CLK_M,
 
 	CLOCK_ID_COUNT,	/* number of clocks */
 	CLOCK_ID_NONE = -1,