[U-Boot] [PATCH 2/6] ARM: tegra: Implement clk_m

[Stephen Warren]

On 08/20/2015 03:42 AM, Thierry Reding wrote:
> From: Thierry Reding <treding at nvidia.com>
>
> 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.

> diff --git a/arch/arm/include/asm/arch-tegra114/clock-tables.h b/arch/arm/include/asm/arch-tegra114/clock-tables.h
> index d8fa0e1d2cee..3f910f5ae8b9 100644
> --- a/arch/arm/include/asm/arch-tegra114/clock-tables.h
> +++ b/arch/arm/include/asm/arch-tegra114/clock-tables.h
> @@ -38,6 +38,7 @@ enum clock_id {
>   	/* 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 PLLs */
>   	CLOCK_ID_DISPLAY2,	/* placeholder */

clock.h contains the following:

/* Number of PLL-based clocks (i.e. not OSC or 32KHz) */
#define CLOCK_ID_PLL_COUNT	(CLOCK_ID_COUNT - 2)

... which would need to be updated. Related, see internal bug number 
1676978 to see if any of the other gotchas there affect this patch.