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-tegra/clock.h b/arch/arm/include/asm/arch-tegra/clock.h
index d570d7f..e56031d 100644
--- a/arch/arm/include/asm/arch-tegra/clock.h
+++ b/arch/arm/include/asm/arch-tegra/clock.h
@@ -44,6 +44,9 @@
 /* return the current oscillator clock frequency */
 enum clock_osc_freq clock_get_osc_freq(void);
 
+/* return the clk_m frequency */
+unsigned int clk_m_get_rate(unsigned int parent_rate);
+
 /**
  * Start PLL using the provided configuration parameters.
  *
@@ -338,8 +341,8 @@
 
 void tegra30_set_up_pllp(void);
 
-/* Number of PLL-based clocks (i.e. not OSC or 32KHz) */
-#define CLOCK_ID_PLL_COUNT	(CLOCK_ID_COUNT - 2)
+/* Number of PLL-based clocks (i.e. not OSC, MCLK or 32KHz) */
+#define CLOCK_ID_PLL_COUNT	(CLOCK_ID_COUNT - 3)
 
 struct clk_pll_info {
 	u32	m_shift:5;	/* DIVM_SHIFT */