soc/intel/apollolake: Add PrmrrSize and SGX enable config

Add PrmrrSize and sgx_enable config option. PrmrrSize gets
configured in romstage so that FSP can allocate memory for SGX.
Also, adjust cbmem_top() calculation.

Change-Id: I56165ca201163a8b8b522e9aeb47bd1f4267be5e
Signed-off-by: Pratik Prajapati <pratikkumar.v.prajapati@intel.com>
Reviewed-on: https://review.coreboot.org/21274
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Subrata Banik <subrata.banik@intel.com>

src/soc/intel/apollolake/chip.h

@@ -121,6 +121,18 @@ struct soc_intel_apollolake_config {
 
 	/* GPIO SD card detect pin */
 	unsigned int sdcard_cd_gpio;
+
+	/* PRMRR size setting with three options
+	 *  0x02000000 - 32MiB
+	 *  0x04000000 - 64MiB
+	 *  0x08000000 - 128MiB */
+	uint32_t PrmrrSize;
+
+	/* Enable SGX feature.
+	 * Enabling SGX feature is 2 step process,
+	 * (1) set sgx_enable = 1
+	 * (2) set PrmrrSize to supported size */
+	uint8_t sgx_enable;
 };
 
 typedef struct soc_intel_apollolake_config config_t;