lib/stage_cache: Refactor Kconfig options

Add explicit CBMEM_STAGE_CACHE option. Rename
CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM to TSEG_STAGE_CACHE.

Platforms with SMM_TSEG=y always need to implement
stage_cache_external_region(). It is allowed to return with a
region of size 0 to effectively disable the cache.

There are no provisions in Kconfig to degrade from
TSEG_STAGE_CACHE to CBMEM_STAGE_CACHE.

As a security measure CBMEM_STAGE_CACHE default is changed to
disabled. AGESA platforms without TSEG will experience slower
S3 resume speed unless they explicitly select the option.

Change-Id: Ibbdc701ea85b5a3208ca4e98c428b05b6d4e5340
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34664
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/soc/intel/apollolake/Kconfig

@@ -40,7 +40,6 @@ config CPU_SPECIFIC_OPTIONS
 	# Misc options
 	select C_ENVIRONMENT_BOOTBLOCK
 	select CACHE_MRC_SETTINGS
-	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select COLLECT_TIMESTAMPS
 	select COMMON_FADT
 	select FSP_PLATFORM_MEMORY_SETTINGS_VERSIONS

src/soc/intel/braswell/Kconfig

@@ -14,7 +14,6 @@ config CPU_SPECIFIC_OPTIONS
 	select ARCH_VERSTAGE_X86_32
 	select BOOT_DEVICE_SUPPORTS_WRITES
 	select CACHE_MRC_SETTINGS
-	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select COLLECT_TIMESTAMPS
 	select SUPPORT_CPU_UCODE_IN_CBFS
 	select MICROCODE_BLOB_NOT_IN_BLOB_REPO

src/soc/intel/broadwell/Kconfig

@@ -15,7 +15,6 @@ config CPU_SPECIFIC_OPTIONS
 	select BOOT_DEVICE_SUPPORTS_WRITES
 	select CACHE_MRC_SETTINGS
 	select MRC_SETTINGS_PROTECT
-	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select CPU_INTEL_FIRMWARE_INTERFACE_TABLE
 	select SUPPORT_CPU_UCODE_IN_CBFS
 	select HAVE_SMI_HANDLER

src/soc/intel/cannonlake/Kconfig

@@ -59,7 +59,6 @@ config CPU_SPECIFIC_OPTIONS
 	select BOOT_DEVICE_SUPPORTS_WRITES
 	select C_ENVIRONMENT_BOOTBLOCK
 	select CACHE_MRC_SETTINGS
-	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select COMMON_FADT
 	select CPU_INTEL_COMMON
 	select CPU_INTEL_FIRMWARE_INTERFACE_TABLE

src/soc/intel/icelake/Kconfig

@@ -16,7 +16,6 @@ config CPU_SPECIFIC_OPTIONS
 	select BOOT_DEVICE_SUPPORTS_WRITES
 	select C_ENVIRONMENT_BOOTBLOCK
 	select CACHE_MRC_SETTINGS
-	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select COMMON_FADT
 	select CPU_INTEL_FIRMWARE_INTERFACE_TABLE
 	select FSP_M_XIP

src/soc/intel/skylake/Kconfig

@@ -27,7 +27,6 @@ config CPU_SPECIFIC_OPTIONS
 	select BOOT_DEVICE_SPI_FLASH_RW_NOMMAP_EARLY if BOOT_DEVICE_SPI_FLASH
 	select BOOT_DEVICE_SUPPORTS_WRITES
 	select CACHE_MRC_SETTINGS
-	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select COLLECT_TIMESTAMPS
 	select COMMON_FADT
 	select CPU_INTEL_COMMON