[PATCH 32/32] x86: fsp: Adjust calculations for MTRR range and DRAM top

[Bin Meng]

On Mon, Sep 28, 2020 at 12:26 PM Simon Glass <sjg at chromium.org> wrote:
>
> At present the top of available DRAM is the same as the top of the range
> of the low-memory MTRR.
>
> In fact, U-Boot is allowed to use memory up until the start of the FSP
> reserved memory. Use that value for low_end, since it makes more memory
> available.
>
> Keep the same calculation as before for mtrr_top, i.e. the top of
> reserved memory.
>
> A side-effect of this change is that the E820 tables have a single entry
> that extends from the bottom of the memory used by U-Boot to the bottom
> of the FSP reserved memory. This includes the bloblist, if ACPI tables
> are placed there.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>  arch/x86/lib/fsp/fsp_dram.c | 35 ++++++++++++++++++++++-------------
>  1 file changed, 22 insertions(+), 13 deletions(-)
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>