arch/x86: Obsolete CACHE_AS_RAM config

It was originally inverse of romcc-built romstages on x86,
and is currently always true on x86.

Change-Id: I65fa6b3ce8a86781724bbf08f5eadee4112667c4
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34806
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/cpu/Kconfig

@@ -6,14 +6,9 @@ source "src/cpu/*/Kconfig"
 
 if ARCH_X86
 
-config CACHE_AS_RAM
-	bool
-	default y
-
 config CAR_GLOBAL_MIGRATION
 	bool
 	default n
-	depends on CACHE_AS_RAM
 	help
 	  This option is selected if there is need to migrate CAR globals.
 	  All stages which use CAR globals can directly access the variables

src/cpu/x86/Makefile.inc

@@ -1,8 +1,4 @@
-ifeq ($(CONFIG_ARCH_ROMSTAGE_X86_32)$(CONFIG_ARCH_ROMSTAGE_X86_64),y)
-ifeq ($(CONFIG_CAR_GLOBAL_MIGRATION),y)
-romstage-$(CONFIG_CACHE_AS_RAM) += car.c
-endif
-endif
+romstage-$(CONFIG_CAR_GLOBAL_MIGRATION) += car.c
 
 subdirs-y += pae
 subdirs-$(CONFIG_PARALLEL_MP) += name

src/include/rules.h

@@ -284,7 +284,7 @@
 /* x86 specific. Indicates that the current stage is running with cache-as-ram
  * enabled from the beginning of the stage in C code. */
 #if defined(__PRE_RAM__)
-#define ENV_CACHE_AS_RAM CONFIG(CACHE_AS_RAM)
+#define ENV_CACHE_AS_RAM CONFIG(ARCH_X86)
 #else
 #define ENV_CACHE_AS_RAM 0
 #endif

src/include/symbols.h

@@ -72,7 +72,7 @@ DECLARE_REGION(bl31)
  * (Does not necessarily mean that the memory is accessible.) */
 static inline int preram_symbols_available(void)
 {
-	return !CONFIG(CACHE_AS_RAM) || ENV_CACHE_AS_RAM;
+	return !CONFIG(ARCH_X86) || ENV_CACHE_AS_RAM;
 }
 
 #endif /* __SYMBOLS_H */