[U-Boot] [PATCH] Tegra: Configure L2 cache control reg properly.

[Stephen Warren]

On 03/29/2013 02:38 PM, Tom Warren wrote:
> Without this change, kernel fails at calling function cache_clean_flush
> during kernel early boot.
> 
> Aprocryphally, intended for T114 only, so I check for a T114 SoC.
> Works (i.e. dalmore 3.8 kernel now starts printing to console).

I don't know enough about the caches to really review this, but I have
no particular objection to it. My one comment is ...

> diff --git a/arch/arm/cpu/tegra-common/cache.c b/arch/arm/cpu/tegra-common/cache.c

> +void config_cache(void)

> +	/* Currently, only T114 needs this L2 cache change to boot Linux */
> +	reg = (readl(&gp->hidrev) & HIDREV_CHIPID_MASK);
> +	if (reg != (CHIPID_TEGRA114 << HIDREV_CHIPID_SHIFT))
> +		return;

Can we introduce a standard function for that instead? We already have
tegra_get_chip_type() which returns a SKU-based ID. I think we need to
introduce a tegra_get_soc_type() that returns a pure Tegra20/30/114
value, and probably use this in most places we currently use the result
of tegra_get_chip_type(), since most care about SW-compatibility of
features rather than SKU which drivers performance levels instead
typically. Then, perhaps rename tegra_get_chip_type() to
tegra_get_soc_sku() and re-write it to use tegra_get_soc_type()?