[U-Boot] [RFC] ARM: davinci: da850: Enable Caches for DA850-EVM

[Adam Ford]

On Sun, Aug 27, 2017 at 5:39 PM, Adam Ford <aford173 at gmail.com> wrote:
> What starting up the DA850-EVM, U-Boot generates a warning:
>    WARNING: Caches not enabled
>
> Looking at other arm926 processors, this is an attempt
> to enable the caches and remove the warning.
>
> I am notsure who the proper TI or ARM people are to review this.
>

For what It's worth, I ran some whetstone benchmarks.  Using 1000 loops,
the da850-evm increased from 14.3 MIPS without cache to 16.7 MIPS with cache

> Signed-off-by: Adam Ford <aford173 at gmail.com>
> ---
>  board/davinci/da8xxevm/da850evm.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
>
> diff --git a/board/davinci/da8xxevm/da850evm.c b/board/davinci/da8xxevm/da850evm.c
> index c2d2e8e..33a923c 100644
> --- a/board/davinci/da8xxevm/da850evm.c
> +++ b/board/davinci/da8xxevm/da850evm.c
> @@ -491,3 +491,29 @@ int board_eth_init(bd_t *bis)
>         return 0;
>  }
>  #endif /* CONFIG_DRIVER_TI_EMAC */
> +
> +#ifndef CONFIG_SYS_ICACHE_OFF
> +/* Invalidate entire I-cache and branch predictor array */
> +void invalidate_icache_all(void)
> +{
> +       unsigned long i = 0;
> +
> +       asm ("mcr p15, 0, %0, c7, c5, 0" : : "r" (i));
> +}
> +#else
> +void invalidate_icache_all(void)
> +{
> +}
> +#endif
> +
> +#ifndef CONFIG_SYS_DCACHE_OFF
> +void enable_caches(void)
> +{
> +       /* Enable D-cache. I-cache is already enabled in start.S */
> +       dcache_enable();
> +}
> +#else
> +void enable_caches(void)
> +{
> +}
> +#endif /* CONFIG_SYS_DCACHE_OFF */
> --
> 2.7.4
>