soc/intel: Use common romstage code

This provides stack guards with checking and common
entry into postcar.

The code in cpu/intel/car/romstage.c is candidate
for becoming architectural so function prototype
is moved to <arch/romstage.h>.

Change-Id: I4c5a9789e7cf3f7f49a4a33e21dac894320a9639
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34893
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

56 files changed, 133 insertions, 201 deletions

diff --git a/src/arch/x86/include/arch/romstage.h b/src/arch/x86/include/arch/romstage.h
index 42c9fbb6cd..7816a7c0bc 100644
--- a/src/arch/x86/include/arch/romstage.h
+++ b/src/arch/x86/include/arch/romstage.h
@@ -18,6 +18,8 @@
 #include <stddef.h>
 #include <stdint.h>
 
+void mainboard_romstage_entry(void);
+
 /*
  * Support setting up a stack frame consisting of MTRR information
  * for use in bootstrapping the caching attributes after cache-as-ram
@@ -62,6 +64,20 @@ void postcar_frame_common_mtrrs(struct postcar_frame *pcf);
 void *postcar_commit_mtrrs(struct postcar_frame *pcf);
 
 /*
+ * fill_postcar_frame() is called after raminit completes and right before
+ * calling run_postcar_phase(). Implementation should call postcar_frame_add_mtrr()
+ * to tag memory ranges as cacheable to speed up execution of postcar and
+ * early ramstage.
+ */
+void fill_postcar_frame(struct postcar_frame *pcf);
+
+/*
+ * prepare_and_run_postcar() determines the stack to use after
+ * cache-as-ram is torn down as well as the MTRR settings to use.
+ */
+void prepare_and_run_postcar(struct postcar_frame *pcf);
+
+/*
  * Load and run a program that takes control of execution that
  * tears down CAR and loads ramstage. The postcar_frame object
  * indicates how to set up the frame. If caching is enabled at
diff --git a/src/arch/x86/postcar_loader.c b/src/arch/x86/postcar_loader.c
index 816f41e412..4a7d549347 100644
--- a/src/arch/x86/postcar_loader.c
+++ b/src/arch/x86/postcar_loader.c
@@ -132,6 +132,21 @@ void postcar_frame_common_mtrrs(struct postcar_frame *pcf)
 	postcar_frame_add_romcache(pcf, MTRR_TYPE_WRPROT);
 }
 
+/* prepare_and_run_postcar() determines the stack to use after
+ * cache-as-ram is torn down as well as the MTRR settings to use. */
+void prepare_and_run_postcar(struct postcar_frame *pcf)
+{
+	if (postcar_frame_init(pcf, 0))
+		die("Unable to initialize postcar frame.\n");
+
+	fill_postcar_frame(pcf);
+
+	postcar_frame_common_mtrrs(pcf);
+
+	run_postcar_phase(pcf);
+	/* We do not return here. */
+}
+
 void *postcar_commit_mtrrs(struct postcar_frame *pcf)
 {
 	/*
diff --git a/src/cpu/intel/car/romstage.c b/src/cpu/intel/car/romstage.c
index a0dc743806..ac81b021a8 100644
--- a/src/cpu/intel/car/romstage.c
+++ b/src/cpu/intel/car/romstage.c
@@ -15,7 +15,6 @@
 #include <arch/romstage.h>
 #include <bootblock_common.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <cpu/x86/smm.h>
 #include <arch/symbols.h>
@@ -29,21 +28,6 @@
 
 static struct postcar_frame early_mtrrs;
 
-/* prepare_and_run_postcar() determines the stack to use after
- * cache-as-ram is torn down as well as the MTRR settings to use. */
-static void prepare_and_run_postcar(struct postcar_frame *pcf)
-{
-	if (postcar_frame_init(pcf, 0))
-		die("Unable to initialize postcar frame.\n");
-
-	fill_postcar_frame(pcf);
-
-	postcar_frame_common_mtrrs(pcf);
-
-	run_postcar_phase(pcf);
-	/* We do not return here. */
-}
-
 static void romstage_main(unsigned long bist)
 {
 	int i;
diff --git a/src/drivers/intel/fsp1_1/car.c b/src/drivers/intel/fsp1_1/car.c
index fafe8384b4..8957c99219 100644
--- a/src/drivers/intel/fsp1_1/car.c
+++ b/src/drivers/intel/fsp1_1/car.c
@@ -18,7 +18,6 @@
 #include <cbmem.h>
 #include <console/console.h>
 #include <commonlib/helpers.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <cpu/x86/smm.h>
 #include <fsp/car.h>
diff --git a/src/include/cpu/intel/romstage.h b/src/include/cpu/intel/romstage.h
deleted file mode 100644
index fd5d7f4e85..0000000000
--- a/src/include/cpu/intel/romstage.h
+++ /dev/null
@@ -1,14 +0,0 @@
-#ifndef _CPU_INTEL_ROMSTAGE_H
-#define _CPU_INTEL_ROMSTAGE_H
-
-#include <arch/romstage.h>
-
-void mainboard_romstage_entry(void);
-
-/* fill_postcar_frame() is called after raminit completes and right before
- * calling run_postcar_phase(). Implementation should call postcar_frame_add_mtrr()
- * to tag memory ranges as cacheable to speed up execution of postcar and
- * early ramstage. */
-void fill_postcar_frame(struct postcar_frame *pcf);
-
-#endif /* _CPU_INTEL_ROMSTAGE_H */
diff --git a/src/mainboard/aopen/dxplplusu/romstage.c b/src/mainboard/aopen/dxplplusu/romstage.c
index c95eeda358..7f66fc5aea 100644
--- a/src/mainboard/aopen/dxplplusu/romstage.c
+++ b/src/mainboard/aopen/dxplplusu/romstage.c
@@ -16,7 +16,7 @@
 #include <stdint.h>
 #include <cbmem.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 
 #include <southbridge/intel/i82801dx/i82801dx.h>
 #include <northbridge/intel/e7505/raminit.h>
diff --git a/src/mainboard/apple/macbook21/romstage.c b/src/mainboard/apple/macbook21/romstage.c
index ad09c5c68e..32a7871ecf 100644
--- a/src/mainboard/apple/macbook21/romstage.c
+++ b/src/mainboard/apple/macbook21/romstage.c
@@ -19,7 +19,7 @@
 #include <cf9_reset.h>
 #include <device/pci_ops.h>
 #include <device/pci_def.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/x86/lapic.h>
 #include <console/console.h>
 #include <northbridge/intel/i945/i945.h>
diff --git a/src/mainboard/asrock/g41c-gs/romstage.c b/src/mainboard/asrock/g41c-gs/romstage.c
index 7a2004f141..0228499181 100644
--- a/src/mainboard/asrock/g41c-gs/romstage.c
+++ b/src/mainboard/asrock/g41c-gs/romstage.c
@@ -18,7 +18,7 @@
 #include <device/pnp_ops.h>
 #include <device/pci_ops.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/x4x/iomap.h>
 #include <northbridge/intel/x4x/x4x.h>
 #include <southbridge/intel/common/gpio.h>
diff --git a/src/mainboard/asrock/h81m-hds/romstage.c b/src/mainboard/asrock/h81m-hds/romstage.c
index 91667ded57..3deae7510f 100644
--- a/src/mainboard/asrock/h81m-hds/romstage.c
+++ b/src/mainboard/asrock/h81m-hds/romstage.c
@@ -16,7 +16,7 @@
  */
 
 #include <stdint.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/intel/haswell/haswell.h>
 #include <device/pnp_ops.h>
 #include <northbridge/intel/haswell/haswell.h>
diff --git a/src/mainboard/asus/p2b-ds/romstage.c b/src/mainboard/asus/p2b-ds/romstage.c
index a93c0ed2a9..5b3a30b4f9 100644
--- a/src/mainboard/asus/p2b-ds/romstage.c
+++ b/src/mainboard/asus/p2b-ds/romstage.c
@@ -18,7 +18,7 @@
 #include <console/console.h>
 #include <southbridge/intel/i82371eb/i82371eb.h>
 #include <northbridge/intel/i440bx/raminit.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/winbond/common/winbond.h>
 #include <superio/winbond/w83977tf/w83977tf.h>
 #include <cbmem.h>
diff --git a/src/mainboard/asus/p2b-ls/romstage.c b/src/mainboard/asus/p2b-ls/romstage.c
index e77e3dc18d..f933c772d2 100644
--- a/src/mainboard/asus/p2b-ls/romstage.c
+++ b/src/mainboard/asus/p2b-ls/romstage.c
@@ -18,7 +18,7 @@
 #include <console/console.h>
 #include <southbridge/intel/i82371eb/i82371eb.h>
 #include <northbridge/intel/i440bx/raminit.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/winbond/common/winbond.h>
 /* FIXME: The ASUS P2B-LS has a Winbond W83977EF, actually. */
 #include <superio/winbond/w83977tf/w83977tf.h>
diff --git a/src/mainboard/asus/p2b/romstage.c b/src/mainboard/asus/p2b/romstage.c
index b51742907e..1d7c928f17 100644
--- a/src/mainboard/asus/p2b/romstage.c
+++ b/src/mainboard/asus/p2b/romstage.c
@@ -18,7 +18,7 @@
 #include <console/console.h>
 #include <southbridge/intel/i82371eb/i82371eb.h>
 #include <northbridge/intel/i440bx/raminit.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/winbond/common/winbond.h>
 #include <superio/winbond/w83977tf/w83977tf.h>
 #include <cbmem.h>
diff --git a/src/mainboard/asus/p3b-f/romstage.c b/src/mainboard/asus/p3b-f/romstage.c
index cc5b764b01..8fc135d1c8 100644
--- a/src/mainboard/asus/p3b-f/romstage.c
+++ b/src/mainboard/asus/p3b-f/romstage.c
@@ -19,7 +19,7 @@
 #include <console/console.h>
 #include <southbridge/intel/i82371eb/i82371eb.h>
 #include <northbridge/intel/i440bx/raminit.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/winbond/common/winbond.h>
 /* FIXME: The ASUS P3B-F has a Winbond W83977EF, actually. */
 #include <superio/winbond/w83977tf/w83977tf.h>
diff --git a/src/mainboard/asus/p5gc-mx/romstage.c b/src/mainboard/asus/p5gc-mx/romstage.c
index c3275b5fe1..632ef05573 100644
--- a/src/mainboard/asus/p5gc-mx/romstage.c
+++ b/src/mainboard/asus/p5gc-mx/romstage.c
@@ -24,7 +24,7 @@
 #include <superio/winbond/common/winbond.h>
 #include <superio/winbond/w83627dhg/w83627dhg.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/asus/p5qc/romstage.c b/src/mainboard/asus/p5qc/romstage.c
index 8af04e3cf9..1477d80ea3 100644
--- a/src/mainboard/asus/p5qc/romstage.c
+++ b/src/mainboard/asus/p5qc/romstage.c
@@ -20,7 +20,7 @@
 #include <southbridge/intel/common/gpio.h>
 #include <southbridge/intel/common/pmclib.h>
 #include <northbridge/intel/x4x/x4x.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/winbond/w83667hg-a/w83667hg-a.h>
 #include <superio/winbond/common/winbond.h>
 #include <northbridge/intel/x4x/iomap.h>
diff --git a/src/mainboard/asus/p5qpl-am/romstage.c b/src/mainboard/asus/p5qpl-am/romstage.c
index f15a187d94..dc589a5918 100644
--- a/src/mainboard/asus/p5qpl-am/romstage.c
+++ b/src/mainboard/asus/p5qpl-am/romstage.c
@@ -19,7 +19,7 @@
 #include <device/pnp_ops.h>
 #include <device/pci_ops.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/intel/speedstep.h>
 #include <cpu/x86/msr.h>
 #include <northbridge/intel/x4x/iomap.h>
diff --git a/src/mainboard/foxconn/g41s-k/romstage.c b/src/mainboard/foxconn/g41s-k/romstage.c
index 16c3b47a30..a22c90c1f1 100644
--- a/src/mainboard/foxconn/g41s-k/romstage.c
+++ b/src/mainboard/foxconn/g41s-k/romstage.c
@@ -17,7 +17,7 @@
  */
 
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <device/pci_ops.h>
 #include <northbridge/intel/x4x/iomap.h>
 #include <northbridge/intel/x4x/x4x.h>
diff --git a/src/mainboard/getac/p470/romstage.c b/src/mainboard/getac/p470/romstage.c
index 2740aaa058..ff4c99ed4d 100644
--- a/src/mainboard/getac/p470/romstage.c
+++ b/src/mainboard/getac/p470/romstage.c
@@ -24,7 +24,7 @@
 #include <cpu/x86/lapic.h>
 #include <pc80/mc146818rtc.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/gigabyte/ga-945gcm-s2l/romstage.c b/src/mainboard/gigabyte/ga-945gcm-s2l/romstage.c
index 7a2b38499b..eaf05a2c38 100644
--- a/src/mainboard/gigabyte/ga-945gcm-s2l/romstage.c
+++ b/src/mainboard/gigabyte/ga-945gcm-s2l/romstage.c
@@ -21,7 +21,7 @@
 #include <superio/ite/it8718f/it8718f.h>
 #include <superio/ite/common/ite.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/gigabyte/ga-g41m-es2l/romstage.c b/src/mainboard/gigabyte/ga-g41m-es2l/romstage.c
index c13d4d6419..989a0cb941 100644
--- a/src/mainboard/gigabyte/ga-g41m-es2l/romstage.c
+++ b/src/mainboard/gigabyte/ga-g41m-es2l/romstage.c
@@ -22,7 +22,7 @@
 #include <southbridge/intel/common/gpio.h>
 #include <southbridge/intel/common/pmclib.h>
 #include <northbridge/intel/x4x/x4x.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/ite/it8718f/it8718f.h>
 #include <superio/ite/common/ite.h>
 #include <northbridge/intel/x4x/iomap.h>
diff --git a/src/mainboard/google/beltino/romstage.c b/src/mainboard/google/beltino/romstage.c
index d36971fc39..f2066647d0 100644
--- a/src/mainboard/google/beltino/romstage.c
+++ b/src/mainboard/google/beltino/romstage.c
@@ -16,7 +16,7 @@
 
 #include <stdint.h>
 #include <stdlib.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/intel/haswell/haswell.h>
 #include <northbridge/intel/haswell/haswell.h>
 #include <northbridge/intel/haswell/raminit.h>
diff --git a/src/mainboard/google/slippy/romstage.c b/src/mainboard/google/slippy/romstage.c
index 3f6d989fd4..3a2d96f3a0 100644
--- a/src/mainboard/google/slippy/romstage.c
+++ b/src/mainboard/google/slippy/romstage.c
@@ -14,7 +14,7 @@
  * GNU General Public License for more details.
  */
 
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include "variant.h"
 
 
diff --git a/src/mainboard/ibase/mb899/romstage.c b/src/mainboard/ibase/mb899/romstage.c
index 847cc5f584..82dbba5dc5 100644
--- a/src/mainboard/ibase/mb899/romstage.c
+++ b/src/mainboard/ibase/mb899/romstage.c
@@ -18,7 +18,7 @@
 #include <device/pnp_ops.h>
 #include <device/pci_ops.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/x86/lapic.h>
 #include <device/pci_def.h>
 #include <device/pnp_def.h>
diff --git a/src/mainboard/intel/baskingridge/romstage.c b/src/mainboard/intel/baskingridge/romstage.c
index 3fd9aab9c7..1a10931431 100644
--- a/src/mainboard/intel/baskingridge/romstage.c
+++ b/src/mainboard/intel/baskingridge/romstage.c
@@ -16,7 +16,7 @@
 
 #include <stdint.h>
 #include <stddef.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/intel/haswell/haswell.h>
 #include <northbridge/intel/haswell/haswell.h>
 #include <northbridge/intel/haswell/raminit.h>
diff --git a/src/mainboard/intel/d945gclf/romstage.c b/src/mainboard/intel/d945gclf/romstage.c
index 15acffb052..bad2b6d538 100644
--- a/src/mainboard/intel/d945gclf/romstage.c
+++ b/src/mainboard/intel/d945gclf/romstage.c
@@ -19,7 +19,7 @@
 #include <cpu/x86/lapic.h>
 #include <superio/smsc/lpc47m15x/lpc47m15x.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/intel/dg41wv/romstage.c b/src/mainboard/intel/dg41wv/romstage.c
index ec3e2bfbe6..74f86221eb 100644
--- a/src/mainboard/intel/dg41wv/romstage.c
+++ b/src/mainboard/intel/dg41wv/romstage.c
@@ -18,7 +18,7 @@
 #include <device/pnp_ops.h>
 #include <device/pci_ops.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/x4x/iomap.h>
 #include <northbridge/intel/x4x/x4x.h>
 #include <southbridge/intel/common/gpio.h>
diff --git a/src/mainboard/intel/dg43gt/romstage.c b/src/mainboard/intel/dg43gt/romstage.c
index db896824cd..8207638a5b 100644
--- a/src/mainboard/intel/dg43gt/romstage.c
+++ b/src/mainboard/intel/dg43gt/romstage.c
@@ -20,7 +20,7 @@
 #include <southbridge/intel/common/gpio.h>
 #include <southbridge/intel/common/pmclib.h>
 #include <northbridge/intel/x4x/x4x.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <superio/winbond/w83627dhg/w83627dhg.h>
 #include <superio/winbond/common/winbond.h>
 #include <northbridge/intel/x4x/iomap.h>
diff --git a/src/mainboard/kontron/986lcd-m/romstage.c b/src/mainboard/kontron/986lcd-m/romstage.c
index 0981fe8989..bbaad83089 100644
--- a/src/mainboard/kontron/986lcd-m/romstage.c
+++ b/src/mainboard/kontron/986lcd-m/romstage.c
@@ -17,7 +17,7 @@
 #include <cf9_reset.h>
 #include <delay.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/x86/lapic.h>
 #include <device/pci_def.h>
 #include <device/pci_ops.h>
diff --git a/src/mainboard/lenovo/t60/romstage.c b/src/mainboard/lenovo/t60/romstage.c
index 243e16112e..9e832208b5 100644
--- a/src/mainboard/lenovo/t60/romstage.c
+++ b/src/mainboard/lenovo/t60/romstage.c
@@ -24,7 +24,7 @@
 #include <device/pnp_def.h>
 #include <cpu/x86/lapic.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/lenovo/thinkcentre_a58/romstage.c b/src/mainboard/lenovo/thinkcentre_a58/romstage.c
index bbb73dd57c..e4abab5770 100644
--- a/src/mainboard/lenovo/thinkcentre_a58/romstage.c
+++ b/src/mainboard/lenovo/thinkcentre_a58/romstage.c
@@ -20,7 +20,7 @@
 #include <southbridge/intel/common/gpio.h>
 #include <southbridge/intel/common/pmclib.h>
 #include <northbridge/intel/x4x/x4x.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <device/pci_ops.h>
 #include <superio/smsc/smscsuperio/smscsuperio.h>
 #include <northbridge/intel/x4x/iomap.h>
diff --git a/src/mainboard/lenovo/x201/romstage.c b/src/mainboard/lenovo/x201/romstage.c
index 067528b87b..3a06a8cd93 100644
--- a/src/mainboard/lenovo/x201/romstage.c
+++ b/src/mainboard/lenovo/x201/romstage.c
@@ -23,7 +23,7 @@
 #include <cpu/x86/lapic.h>
 #include <romstage_handoff.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <ec/acpi/ec.h>
 #include <timestamp.h>
 #include <arch/acpi.h>
diff --git a/src/mainboard/lenovo/x60/romstage.c b/src/mainboard/lenovo/x60/romstage.c
index 2b8a9badba..5a8ab942bc 100644
--- a/src/mainboard/lenovo/x60/romstage.c
+++ b/src/mainboard/lenovo/x60/romstage.c
@@ -25,7 +25,7 @@
 #include <cpu/x86/lapic.h>
 #include <arch/acpi.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/lenovo/z61t/romstage.c b/src/mainboard/lenovo/z61t/romstage.c
index 8946179c4a..7f12091ced 100644
--- a/src/mainboard/lenovo/z61t/romstage.c
+++ b/src/mainboard/lenovo/z61t/romstage.c
@@ -24,7 +24,7 @@
 #include <device/pnp_def.h>
 #include <cpu/x86/lapic.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/packardbell/ms2290/romstage.c b/src/mainboard/packardbell/ms2290/romstage.c
index a4d598f93f..66056a794d 100644
--- a/src/mainboard/packardbell/ms2290/romstage.c
+++ b/src/mainboard/packardbell/ms2290/romstage.c
@@ -23,7 +23,7 @@
 #include <cpu/x86/lapic.h>
 #include <romstage_handoff.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <ec/acpi/ec.h>
 #include <timestamp.h>
 #include <arch/acpi.h>
diff --git a/src/mainboard/roda/rk886ex/romstage.c b/src/mainboard/roda/rk886ex/romstage.c
index 196f0a510f..30ebf4431d 100644
--- a/src/mainboard/roda/rk886ex/romstage.c
+++ b/src/mainboard/roda/rk886ex/romstage.c
@@ -24,7 +24,7 @@
 #include <cpu/x86/lapic.h>
 #include <pc80/mc146818rtc.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/i945/i945.h>
 #include <northbridge/intel/i945/raminit.h>
 #include <southbridge/intel/i82801gx/i82801gx.h>
diff --git a/src/mainboard/supermicro/x10slm-f/romstage.c b/src/mainboard/supermicro/x10slm-f/romstage.c
index 228bcb581e..552ebd2113 100644
--- a/src/mainboard/supermicro/x10slm-f/romstage.c
+++ b/src/mainboard/supermicro/x10slm-f/romstage.c
@@ -16,7 +16,7 @@
  */
 
 #include <cpu/intel/haswell/haswell.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/haswell/haswell.h>
 #include <northbridge/intel/haswell/pei_data.h>
 #include <southbridge/intel/common/gpio.h>
diff --git a/src/northbridge/intel/e7505/memmap.c b/src/northbridge/intel/e7505/memmap.c
index 9a63cffeae..11af6e334f 100644
--- a/src/northbridge/intel/e7505/memmap.c
+++ b/src/northbridge/intel/e7505/memmap.c
@@ -18,7 +18,6 @@
 #include <arch/romstage.h>
 #include <cbmem.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <program_loading.h>
 #include "e7505.h"
diff --git a/src/northbridge/intel/gm45/memmap.c b/src/northbridge/intel/gm45/memmap.c
index 4814e356b5..6e2f7037c2 100644
--- a/src/northbridge/intel/gm45/memmap.c
+++ b/src/northbridge/intel/gm45/memmap.c
@@ -22,7 +22,6 @@
 #include <device/pci_ops.h>
 #include <device/pci_def.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <cbmem.h>
 #include <program_loading.h>
diff --git a/src/northbridge/intel/gm45/romstage.c b/src/northbridge/intel/gm45/romstage.c
index 7c16761bb5..c853a3a1f4 100644
--- a/src/northbridge/intel/gm45/romstage.c
+++ b/src/northbridge/intel/gm45/romstage.c
@@ -21,7 +21,7 @@
 #include <device/pci_ops.h>
 #include <arch/acpi.h>
 #include <cpu/x86/lapic.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <northbridge/intel/gm45/gm45.h>
 #include <southbridge/intel/i82801ix/i82801ix.h>
 #include <southbridge/intel/common/gpio.h>
diff --git a/src/northbridge/intel/haswell/memmap.c b/src/northbridge/intel/haswell/memmap.c
index b1d86db51a..5bc74f8703 100644
--- a/src/northbridge/intel/haswell/memmap.c
+++ b/src/northbridge/intel/haswell/memmap.c
@@ -18,10 +18,10 @@
 
 #include <arch/romstage.h>
 #include <console/console.h>
+#include <commonlib/helpers.h>
 #include <cpu/x86/mtrr.h>
 #include <device/pci_ops.h>
 #include <cbmem.h>
-#include <cpu/intel/romstage.h>
 #include <stage_cache.h>
 #include "haswell.h"
 
diff --git a/src/northbridge/intel/i440bx/memmap.c b/src/northbridge/intel/i440bx/memmap.c
index 6a1730eea6..6c540a512a 100644
--- a/src/northbridge/intel/i440bx/memmap.c
+++ b/src/northbridge/intel/i440bx/memmap.c
@@ -20,7 +20,6 @@
 #include <cbmem.h>
 #include <console/console.h>
 #include <commonlib/helpers.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <program_loading.h>
 #include "i440bx.h"
diff --git a/src/northbridge/intel/i945/memmap.c b/src/northbridge/intel/i945/memmap.c
index b0764f67ed..8179f17888 100644
--- a/src/northbridge/intel/i945/memmap.c
+++ b/src/northbridge/intel/i945/memmap.c
@@ -21,7 +21,6 @@
 #include <cbmem.h>
 #include "i945.h"
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <program_loading.h>
 #include <cpu/intel/smm_reloc.h>
diff --git a/src/northbridge/intel/nehalem/memmap.c b/src/northbridge/intel/nehalem/memmap.c
index 8787df6898..1687ddf78b 100644
--- a/src/northbridge/intel/nehalem/memmap.c
+++ b/src/northbridge/intel/nehalem/memmap.c
@@ -20,7 +20,6 @@
 #include <device/pci_ops.h>
 #include <cbmem.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <program_loading.h>
 #include <stage_cache.h>
diff --git a/src/northbridge/intel/pineview/memmap.c b/src/northbridge/intel/pineview/memmap.c
index eaf27f699f..9908f110cd 100644
--- a/src/northbridge/intel/pineview/memmap.c
+++ b/src/northbridge/intel/pineview/memmap.c
@@ -24,7 +24,6 @@
 #include <cbmem.h>
 #include <northbridge/intel/pineview/pineview.h>
 #include <cpu/x86/mtrr.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/intel/smm_reloc.h>
 #include <stdint.h>
 #include <stage_cache.h>
diff --git a/src/northbridge/intel/pineview/romstage.c b/src/northbridge/intel/pineview/romstage.c
index e184f789d0..e60738ced5 100644
--- a/src/northbridge/intel/pineview/romstage.c
+++ b/src/northbridge/intel/pineview/romstage.c
@@ -26,7 +26,7 @@
 #include <southbridge/intel/i82801gx/i82801gx.h>
 #include <southbridge/intel/common/gpio.h>
 #include <southbridge/intel/common/pmclib.h>
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <cpu/x86/lapic.h>
 #include "raminit.h"
 #include "pineview.h"
diff --git a/src/northbridge/intel/sandybridge/memmap.c b/src/northbridge/intel/sandybridge/memmap.c
index 44bbbd201b..fa29b3782b 100644
--- a/src/northbridge/intel/sandybridge/memmap.c
+++ b/src/northbridge/intel/sandybridge/memmap.c
@@ -19,7 +19,6 @@
 #include <device/pci_ops.h>
 #include <cbmem.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/intel/smm_reloc.h>
 #include <cpu/x86/mtrr.h>
 #include <program_loading.h>
diff --git a/src/northbridge/intel/sandybridge/romstage.c b/src/northbridge/intel/sandybridge/romstage.c
index bfcf79dd23..1b402dcc56 100644
--- a/src/northbridge/intel/sandybridge/romstage.c
+++ b/src/northbridge/intel/sandybridge/romstage.c
@@ -22,7 +22,7 @@
 #include <cpu/x86/lapic.h>
 #include <timestamp.h>
 #include "sandybridge.h"
-#include <cpu/intel/romstage.h>
+#include <arch/romstage.h>
 #include <device/pci_def.h>
 #include <device/device.h>
 #include <northbridge/intel/sandybridge/chip.h>
diff --git a/src/northbridge/intel/x4x/memmap.c b/src/northbridge/intel/x4x/memmap.c
index b8a3b94a78..2f50768c46 100644
--- a/src/northbridge/intel/x4x/memmap.c
+++ b/src/northbridge/intel/x4x/memmap.c
@@ -24,7 +24,6 @@
 #include <device/pci_ops.h>
 #include <device/pci_def.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <northbridge/intel/x4x/x4x.h>
 #include <program_loading.h>
diff --git a/src/soc/intel/apollolake/romstage.c b/src/soc/intel/apollolake/romstage.c
index 1464d2c6b3..2c283396c9 100644
--- a/src/soc/intel/apollolake/romstage.c
+++ b/src/soc/intel/apollolake/romstage.c
@@ -16,7 +16,6 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/cpu.h>
 #include <arch/romstage.h>
 #include <device/pci_ops.h>
 #include <arch/symbols.h>
@@ -193,20 +192,15 @@ void set_max_freq(void)
 	cpu_set_p_state_to_turbo_ratio();
 }
 
-asmlinkage void car_stage_entry(void)
+void mainboard_romstage_entry(void)
 {
-	struct postcar_frame pcf;
-	uintptr_t top_of_ram;
 	bool s3wake;
+	size_t var_size;
 	struct chipset_power_state *ps = pmc_get_power_state();
-	uintptr_t smm_base;
-	size_t smm_size, var_size;
 	const void *new_var_data;
 
 	timestamp_add_now(TS_START_ROMSTAGE);
 
-	console_init();
-
 	soc_early_romstage_init();
 
 	s3wake = pmc_fill_power_state(ps) == ACPI_S3;
@@ -227,10 +221,14 @@ asmlinkage void car_stage_entry(void)
 	else
 		printk(BIOS_ERR, "Failed to determine variable data\n");
 
-	if (postcar_frame_init(&pcf, 0))
-		die("Unable to initialize postcar frame.\n");
-
 	mainboard_save_dimm_info();
+}
+
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+	uintptr_t top_of_ram;
+	uintptr_t smm_base;
+	size_t smm_size;
 
 	/*
 	 * We need to make sure ramstage will be run cached. At this point exact
@@ -240,12 +238,9 @@ asmlinkage void car_stage_entry(void)
 	top_of_ram = (uintptr_t) cbmem_top();
 	/* cbmem_top() needs to be at least 16 MiB aligned */
 	assert(ALIGN_DOWN(top_of_ram, 16*MiB) == top_of_ram);
-	postcar_frame_add_mtrr(&pcf, top_of_ram - 16*MiB, 16*MiB,
+	postcar_frame_add_mtrr(pcf, top_of_ram - 16*MiB, 16*MiB,
 		MTRR_TYPE_WRBACK);
 
-	/* Cache the memory-mapped boot media. */
-	postcar_frame_add_romcache(&pcf, MTRR_TYPE_WRPROT);
-
 	/*
 	* Cache the TSEG region at the top of ram. This region is
 	* not restricted to SMM mode until SMM has been relocated.
@@ -254,9 +249,7 @@ asmlinkage void car_stage_entry(void)
 	* region for other purposes.
 	*/
 	smm_region(&smm_base, &smm_size);
-	postcar_frame_add_mtrr(&pcf, smm_base, smm_size, MTRR_TYPE_WRBACK);
-
-	run_postcar_phase(&pcf);
+	postcar_frame_add_mtrr(pcf, smm_base, smm_size, MTRR_TYPE_WRBACK);
 }
 
 static void fill_console_params(FSPM_UPD *mupd)
diff --git a/src/soc/intel/baytrail/romstage/romstage.c b/src/soc/intel/baytrail/romstage/romstage.c
index f20c363a35..aa9fa6b66a 100644
--- a/src/soc/intel/baytrail/romstage/romstage.c
+++ b/src/soc/intel/baytrail/romstage/romstage.c
@@ -54,23 +54,6 @@
 
 static struct postcar_frame early_mtrrs;
 
-static void fill_postcar_frame(struct postcar_frame *pcf);
-
-/* prepare_and_run_postcar() determines the stack to use after
- * cache-as-ram is torn down as well as the MTRR settings to use. */
-static void prepare_and_run_postcar(struct postcar_frame *pcf)
-{
-	if (postcar_frame_init(pcf, 0))
-		die("Unable to initialize postcar frame.\n");
-
-	fill_postcar_frame(pcf);
-
-	postcar_frame_common_mtrrs(pcf);
-
-	run_postcar_phase(pcf);
-	/* We do not return here. */
-}
-
 static void program_base_addresses(void)
 {
 	uint32_t reg;
@@ -260,7 +243,7 @@ void romstage_common(struct romstage_params *params)
 	romstage_handoff_init(prev_sleep_state == ACPI_S3);
 }
 
-static void fill_postcar_frame(struct postcar_frame *pcf)
+void fill_postcar_frame(struct postcar_frame *pcf)
 {
 	uintptr_t top_of_ram;
 
diff --git a/src/soc/intel/broadwell/romstage/romstage.c b/src/soc/intel/broadwell/romstage/romstage.c
index 3f264ff5ec..b3662e1591 100644
--- a/src/soc/intel/broadwell/romstage/romstage.c
+++ b/src/soc/intel/broadwell/romstage/romstage.c
@@ -21,7 +21,6 @@
 #include <bootmode.h>
 #include <cbmem.h>
 #include <console/console.h>
-#include <cpu/intel/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <elog.h>
 #include <program_loading.h>
diff --git a/src/soc/intel/cannonlake/romstage/romstage.c b/src/soc/intel/cannonlake/romstage/romstage.c
index 9f02c8b1d3..5711c15142 100644
--- a/src/soc/intel/cannonlake/romstage/romstage.c
+++ b/src/soc/intel/cannonlake/romstage/romstage.c
@@ -13,7 +13,6 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/cpu.h>
 #include <arch/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <cbmem.h>
@@ -128,15 +127,11 @@ static void save_dimm_info(void)
 	printk(BIOS_DEBUG, "%d DIMMs found\n", mem_info->dimm_cnt);
 }
 
-asmlinkage void car_stage_entry(void)
+void mainboard_romstage_entry(void)
 {
 	bool s3wake;
-	struct postcar_frame pcf;
-	uintptr_t top_of_ram;
 	struct chipset_power_state *ps = pmc_get_power_state();
 
-	console_init();
-
 	/* Program MCHBAR, DMIBAR, GDXBAR and EDRAMBAR */
 	systemagent_early_init();
 	/* initialize Heci interface */
@@ -148,9 +143,11 @@ asmlinkage void car_stage_entry(void)
 	pmc_set_disb();
 	if (!s3wake)
 		save_dimm_info();
-	if (postcar_frame_init(&pcf, 0))
-		die("Unable to initialize postcar frame.\n");
+}
 
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+	uintptr_t top_of_ram;
 	/*
 	 * We need to make sure ramstage will be run cached. At this
 	 * point exact location of ramstage in cbmem is not known.
@@ -160,10 +157,5 @@ asmlinkage void car_stage_entry(void)
 	top_of_ram = (uintptr_t) cbmem_top();
 	printk(BIOS_DEBUG, "top_of_ram = 0x%lx\n", top_of_ram);
 	top_of_ram -= 16*MiB;
-	postcar_frame_add_mtrr(&pcf, top_of_ram, 16*MiB, MTRR_TYPE_WRBACK);
-
-	/* Cache the ROM as WP just below 4GiB. */
-	postcar_frame_add_romcache(&pcf, MTRR_TYPE_WRPROT);
-
-	run_postcar_phase(&pcf);
+	postcar_frame_add_mtrr(pcf, top_of_ram, 16*MiB, MTRR_TYPE_WRBACK);
 }
diff --git a/src/soc/intel/denverton_ns/romstage.c b/src/soc/intel/denverton_ns/romstage.c
index 9c41486aa2..cbd451ae0d 100644
--- a/src/soc/intel/denverton_ns/romstage.c
+++ b/src/soc/intel/denverton_ns/romstage.c
@@ -14,7 +14,6 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/cpu.h>
 #include <arch/romstage.h>
 #include <arch/io.h>
 #include <cbmem.h>
@@ -137,16 +136,8 @@ static void early_tco_init(void)
 	outw(reg16, tco_base + TCO2_STS);
 }
 
-asmlinkage void car_stage_entry(void)
+void mainboard_romstage_entry(void)
 {
-
-	struct postcar_frame pcf;
-	uintptr_t top_of_ram;
-	uintptr_t smm_base;
-	size_t smm_size;
-
-	console_init();
-
 	printk(BIOS_DEBUG, "FSP TempRamInit was successful...\n");
 
 	mainboard_config_gpios();
@@ -158,9 +149,13 @@ asmlinkage void car_stage_entry(void)
 #if CONFIG(DISPLAY_HOBS)
 	display_fsp_smbios_memory_info_hob();
 #endif
+}
 
-	if (postcar_frame_init(&pcf, 0))
-		die("Unable to initialize postcar frame.\n");
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+	uintptr_t top_of_ram;
+	uintptr_t smm_base;
+	size_t smm_size;
 
 	/*
 	 * We need to make sure ramstage will be run cached. At this point exact
@@ -168,12 +163,9 @@ asmlinkage void car_stage_entry(void)
 	 * 16 megs under cbmem top which is a safe bet to cover ramstage.
 	 */
 	top_of_ram = (uintptr_t)cbmem_top();
-	postcar_frame_add_mtrr(&pcf, top_of_ram - 16 * MiB, 16 * MiB,
+	postcar_frame_add_mtrr(pcf, top_of_ram - 16 * MiB, 16 * MiB,
 			       MTRR_TYPE_WRBACK);
 
-	/* Cache the memory-mapped boot media. */
-	postcar_frame_add_romcache(&pcf, MTRR_TYPE_WRPROT);
-
 	/*
 	 * Cache the TSEG region at the top of ram. This region is
 	 * not restricted to SMM mode until SMM has been relocated.
@@ -181,12 +173,8 @@ asmlinkage void car_stage_entry(void)
 	 * when relocating the SMM handler as well as using the TSEG
 	 * region for other purposes.
 	 */
-	if (CONFIG(HAVE_SMI_HANDLER)) {
-		smm_region(&smm_base, &smm_size);
-		postcar_frame_add_mtrr(&pcf, smm_base, smm_size, MTRR_TYPE_WRBACK);
-	}
-
-	run_postcar_phase(&pcf);
+	smm_region(&smm_base, &smm_size);
+	postcar_frame_add_mtrr(pcf, smm_base, smm_size, MTRR_TYPE_WRBACK);
 }
 
 static void soc_memory_init_params(FSP_M_CONFIG *m_cfg)
diff --git a/src/soc/intel/icelake/romstage/romstage.c b/src/soc/intel/icelake/romstage/romstage.c
index 8312f178e4..67ef2bb6ce 100644
--- a/src/soc/intel/icelake/romstage/romstage.c
+++ b/src/soc/intel/icelake/romstage/romstage.c
@@ -13,7 +13,6 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/cpu.h>
 #include <arch/romstage.h>
 #include <cpu/x86/mtrr.h>
 #include <cbmem.h>
@@ -112,15 +111,11 @@ static void save_dimm_info(void)
 	printk(BIOS_DEBUG, "%d DIMMs found\n", mem_info->dimm_cnt);
 }
 
-asmlinkage void car_stage_entry(void)
+void mainboard_romstage_entry(void)
 {
 	bool s3wake;
-	struct postcar_frame pcf;
-	uintptr_t top_of_ram;
 	struct chipset_power_state *ps = pmc_get_power_state();
 
-	console_init();
-
 	/* Program MCHBAR, DMIBAR, GDXBAR and EDRAMBAR */
 	systemagent_early_init();
 	/* initialize Heci interface */
@@ -132,9 +127,11 @@ asmlinkage void car_stage_entry(void)
 	pmc_set_disb();
 	if (!s3wake)
 		save_dimm_info();
-	if (postcar_frame_init(&pcf, 0))
-		die("Unable to initialize postcar frame.\n");
+}
 
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+	uintptr_t top_of_ram;
 	/*
 	 * We need to make sure ramstage will be run cached. At this
 	 * point exact location of ramstage in cbmem is not known.
@@ -144,10 +141,5 @@ asmlinkage void car_stage_entry(void)
 	top_of_ram = (uintptr_t) cbmem_top();
 	printk(BIOS_DEBUG, "top_of_ram = 0x%lx\n", top_of_ram);
 	top_of_ram -= 16*MiB;
-	postcar_frame_add_mtrr(&pcf, top_of_ram, 16*MiB, MTRR_TYPE_WRBACK);
-
-	/* Cache the ROM as WP just below 4GiB. */
-	postcar_frame_add_romcache(&pcf, MTRR_TYPE_WRPROT);
-
-	run_postcar_phase(&pcf);
+	postcar_frame_add_mtrr(pcf, top_of_ram, 16*MiB, MTRR_TYPE_WRBACK);
 }
diff --git a/src/soc/intel/quark/romstage/fsp2_0.c b/src/soc/intel/quark/romstage/fsp2_0.c
index 0489621045..bd30271d77 100644
--- a/src/soc/intel/quark/romstage/fsp2_0.c
+++ b/src/soc/intel/quark/romstage/fsp2_0.c
@@ -28,12 +28,11 @@
 #include <soc/reg_access.h>
 #include <soc/storage_test.h>
 
+static struct postcar_frame early_mtrrs;
+
 asmlinkage void car_stage_c_entry(void)
 {
-	struct postcar_frame pcf;
 	bool s3wake;
-	uintptr_t top_of_ram;
-	uintptr_t top_of_low_usable_memory;
 
 	post_code(0x20);
 	console_init();
@@ -63,28 +62,33 @@ asmlinkage void car_stage_c_entry(void)
 	/* Initialize the PCIe bridges */
 	pcie_init();
 
-	if (postcar_frame_init(&pcf, 0))
-		die("Unable to initialize postcar frame.\n");
+	prepare_and_run_postcar(&early_mtrrs);
+	/* We do not return here. */
+}
+
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+	uintptr_t top_of_ram;
+	uintptr_t top_of_low_usable_memory;
 
 	/* Locate the top of RAM */
 	top_of_low_usable_memory = (uintptr_t) cbmem_top();
 	top_of_ram = ALIGN(top_of_low_usable_memory, 16 * MiB);
 
 	/* Cache postcar and ramstage */
-	postcar_frame_add_mtrr(&pcf, top_of_ram - (16 * MiB), 16 * MiB,
+	postcar_frame_add_mtrr(pcf, top_of_ram - (16 * MiB), 16 * MiB,
 		MTRR_TYPE_WRBACK);
 
 	/* Cache RMU area */
-	postcar_frame_add_mtrr(&pcf, (uintptr_t) top_of_low_usable_memory,
+	postcar_frame_add_mtrr(pcf, (uintptr_t) top_of_low_usable_memory,
 		0x10000, MTRR_TYPE_WRTHROUGH);
 
 	/* Cache ESRAM */
-	postcar_frame_add_mtrr(&pcf, 0x80000000, 0x80000, MTRR_TYPE_WRBACK);
+	postcar_frame_add_mtrr(pcf, 0x80000000, 0x80000, MTRR_TYPE_WRBACK);
 
+	pcf->skip_common_mtrr = 1;
 	/* Cache SPI flash - Write protect not supported */
-	postcar_frame_add_romcache(&pcf, MTRR_TYPE_WRTHROUGH);
-
-	run_postcar_phase(&pcf);
+	postcar_frame_add_romcache(pcf, MTRR_TYPE_WRTHROUGH);
 }
 
 static struct chipset_power_state power_state;
diff --git a/src/soc/intel/skylake/romstage/romstage_fsp20.c b/src/soc/intel/skylake/romstage/romstage_fsp20.c
index 8b5cd18195..2412f22a27 100644
--- a/src/soc/intel/skylake/romstage/romstage_fsp20.c
+++ b/src/soc/intel/skylake/romstage/romstage_fsp20.c
@@ -13,7 +13,6 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/cpu.h>
 #include <arch/romstage.h>
 #include <arch/symbols.h>
 #include <assert.h>
@@ -140,15 +139,11 @@ static void save_dimm_info(void)
 	printk(BIOS_DEBUG, "%d DIMMs found\n", mem_info->dimm_cnt);
 }
 
-asmlinkage void car_stage_entry(void)
+void mainboard_romstage_entry(void)
 {
 	bool s3wake;
-	struct postcar_frame pcf;
-	uintptr_t top_of_ram;
 	struct chipset_power_state *ps;
 
-	console_init();
-
 	/* Program MCHBAR, DMIBAR, GDXBAR and EDRAMBAR */
 	systemagent_early_init();
 
@@ -159,8 +154,13 @@ asmlinkage void car_stage_entry(void)
 	pmc_set_disb();
 	if (!s3wake)
 		save_dimm_info();
-	if (postcar_frame_init(&pcf, 0))
-		die("Unable to initialize postcar frame.\n");
+}
+
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+	uintptr_t top_of_ram;
+	uintptr_t smm_base;
+	size_t smm_size;
 
 	/*
 	 * We need to make sure ramstage will be run cached. At this
@@ -171,28 +171,17 @@ asmlinkage void car_stage_entry(void)
 	top_of_ram = (uintptr_t) cbmem_top();
 	printk(BIOS_DEBUG, "top_of_ram = 0x%lx\n", top_of_ram);
 	top_of_ram -= 16*MiB;
-	postcar_frame_add_mtrr(&pcf, top_of_ram, 16*MiB, MTRR_TYPE_WRBACK);
-
-	if (CONFIG(HAVE_SMI_HANDLER)) {
-		uintptr_t smm_base;
-		size_t smm_size;
+	postcar_frame_add_mtrr(pcf, top_of_ram, 16*MiB, MTRR_TYPE_WRBACK);
 
-		/*
-		 * Cache the TSEG region at the top of ram. This region is
-		 * not restricted to SMM mode until SMM has been relocated.
-		 * By setting the region to cacheable it provides faster access
-		 * when relocating the SMM handler as well as using the TSEG
-		 * region for other purposes.
-		 */
-		smm_region(&smm_base, &smm_size);
-		postcar_frame_add_mtrr(&pcf, smm_base, smm_size,
-					MTRR_TYPE_WRBACK);
-	}
-
-	/* Cache the ROM as WP just below 4GiB. */
-	postcar_frame_add_romcache(&pcf, MTRR_TYPE_WRPROT);
-
-	run_postcar_phase(&pcf);
+	/*
+	 * Cache the TSEG region at the top of ram. This region is
+	 * not restricted to SMM mode until SMM has been relocated.
+	 * By setting the region to cacheable it provides faster access
+	 * when relocating the SMM handler as well as using the TSEG
+	 * region for other purposes.
+	 */
+	smm_region(&smm_base, &smm_size);
+	postcar_frame_add_mtrr(pcf, smm_base, smm_size, MTRR_TYPE_WRBACK);
 }
 
 static void cpu_flex_override(FSP_M_CONFIG *m_cfg)