[coreboot] New patch to review for coreboot: 1e0a9e1 haswell: support for CONFIG_RELOCATABLE_RAMSTAGE

[Stefan Reinauer (stefan.reinauer@coreboot.org)]

Stefan Reinauer (stefan.reinauer at coreboot.org) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/2793

-gerrit

commit 1e0a9e17baf016ce1ef99d8460ebdf928c22db82
Author: Aaron Durbin <adurbin at chromium.org>
Date:   Fri Feb 8 17:38:35 2013 -0600

    haswell: support for CONFIG_RELOCATABLE_RAMSTAGE
    
    Now that CONFIG_RELOCTABLE_RAMSTAGE is available support it on
    Haswell-based systems. This patch is comprised of the following changes:
    
    1. Ensure that memory is not preserved when a relocatable ramstage is
       enabled. There is no need.
    2. Pick the proper stack to use after cache-as-ram is torn down. When
       the ramstage is relocatable, finding a stack to use before vectoring
       into ramstage is impossible since the ramstage is a black box with an
       unknown layout.
    
    Change-Id: I2a07a497f52375569bae9c994432a8e7e7a40224
    Signed-off-by: Aaron Durbin <adurbin at chromium.org>
---
 src/cpu/intel/haswell/romstage.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/cpu/intel/haswell/romstage.c b/src/cpu/intel/haswell/romstage.c
index d62377e..c4a4e8a 100644
--- a/src/cpu/intel/haswell/romstage.c
+++ b/src/cpu/intel/haswell/romstage.c
@@ -60,6 +60,19 @@ static inline u32 *stack_push(u32 *stack, u32 value)
 	return stack;
 }
 
+static unsigned long choose_top_of_stack(void)
+{
+	unsigned long stack_top;
+#if CONFIG_RELOCATABLE_RAMSTAGE
+	stack_top = (unsigned long)cbmem_add(CBMEM_ID_RESUME_SCRATCH,
+	                                     CONFIG_HIGH_SCRATCH_MEMORY_SIZE);
+	stack_top += CONFIG_HIGH_SCRATCH_MEMORY_SIZE;
+#else
+	stack_top = ROMSTAGE_STACK;
+#endif
+	return stack_top;
+}
+
 /* setup_romstage_stack_after_car() determines the stack to use after
  * cache-as-ram is torn down as well as the MTRR settings to use. */
 static void *setup_romstage_stack_after_car(void)
@@ -70,7 +83,7 @@ static void *setup_romstage_stack_after_car(void)
 	u32 mtrr_mask_upper;
 
 	/* Top of stack needs to be aligned to a 4-byte boundary. */
-	top_of_stack = ROMSTAGE_STACK & ~3;
+	top_of_stack = choose_top_of_stack() & ~3;
 	slot = (void *)top_of_stack;
 	num_mtrrs = 0;
 
@@ -245,11 +258,13 @@ void romstage_common(const struct romstage_params *params)
 	*(u32 *)CBMEM_RESUME_BACKUP = 0;
 
 	if ((boot_mode == 2) && cbmem_was_initted) {
+		#if !CONFIG_RELOCATABLE_RAMSTAGE
 		void *resume_backup_memory = cbmem_find(CBMEM_ID_RESUME);
 		if (resume_backup_memory) {
 			*(u32 *)CBMEM_BOOT_MODE = boot_mode;
 			*(u32 *)CBMEM_RESUME_BACKUP = (u32)resume_backup_memory;
 		}
+		#endif
 		/* Magic for S3 resume */
 		pci_write_config32(PCI_DEV(0, 0x00, 0), SKPAD, 0xcafed00d);
 	} else if (boot_mode == 2) {
@@ -277,6 +292,8 @@ void romstage_common(const struct romstage_params *params)
 
 static inline void prepare_for_resume(void)
 {
+/* Only need to save memory when ramstage isn't relocatable. */
+#if !CONFIG_RELOCATABLE_RAMSTAGE
 #if CONFIG_HAVE_ACPI_RESUME
 	/* Back up the OS-controlled memory where ramstage will be loaded. */
 	if (*(u32 *)CBMEM_BOOT_MODE == 2) {
@@ -285,6 +302,7 @@ static inline void prepare_for_resume(void)
 		memcpy(dest, src, HIGH_MEMORY_SAVE);
 	}
 #endif
+#endif
 }
 
 void romstage_after_car(void)