soc/intel/cannonlake: Calculate soc reserved memory size

This patch implements soc override function to calculate reserve memory
size (PRMRR, ME stolen, PTT etc). System memory should reserve those
memory ranges.

BRANCH=none
BUG=b:63974384
TEST=Ensures DRAM based resource allocation has taken care
of intel soc reserved ranges.

Change-Id: I3052a255c4496dc81c8dfc6882d3ad504abae9c6
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/21986
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Lijian Zhao <lijian.zhao@intel.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/cannonlake/memmap.c

@@ -256,6 +256,21 @@ static uintptr_t calculate_dram_base(size_t *reserved_mem_size)
 	return dram_base;
 }
 
+/*
+ * SoC implementation
+ *
+ * SoC call to summarize all Intel Reserve MMIO size and report to SA
+ */
+size_t soc_reserved_mmio_size(void)
+{
+	size_t chipset_mem_size;
+
+	calculate_dram_base(&chipset_mem_size);
+
+	/* Get Intel Reserved Memory Range Size */
+	return chipset_mem_size;
+}
+
 /* Fill up memory layout information */
 void fill_soc_memmap_ebda(struct ebda_config *cfg)
 {