haswell: use s3_resume field in romstage_handoff

Now that there is a way to disseminate the presence of s3 wake more
formally use that instead of hard coded pointers in memory and stashing
magic values in device registers. The northbridge code picks up the
field's presence in the romstage_handoff structure and sets up the
acpi_slp_type variable accordingly.

Change-Id: Ida786728ce2950bd64610a99b7ad4f1ca6917a99
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/2799
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

2 files changed, 37 insertions, 39 deletions

diff --git a/src/cpu/intel/haswell/romstage.c b/src/cpu/intel/haswell/romstage.c
index c4a4e8ab2a..ac0e848c7d 100644
--- a/src/cpu/intel/haswell/romstage.c
+++ b/src/cpu/intel/haswell/romstage.c
@@ -34,6 +34,7 @@
 #include <device/pci_def.h>
 #include <cpu/x86/lapic.h>
 #include <cbmem.h>
+#include <romstage_handoff.h>
 #if CONFIG_CHROMEOS
 #include <vendorcode/google/chromeos/chromeos.h>
 #endif
@@ -173,9 +174,10 @@ void * __attribute__((regparm(0))) romstage_main(unsigned long bist)
 
 void romstage_common(const struct romstage_params *params)
 {
-	int boot_mode = 0;
+	int boot_mode;
 	int wake_from_s3;
 	int cbmem_was_initted;
+	struct romstage_handoff *handoff;
 
 #if CONFIG_COLLECT_TIMESTAMPS
 	tsc_t start_romstage_time;
@@ -208,14 +210,18 @@ void romstage_common(const struct romstage_params *params)
 	if (wake_from_s3) {
 #if CONFIG_HAVE_ACPI_RESUME
 		printk(BIOS_DEBUG, "Resume from S3 detected.\n");
-		boot_mode = 2;
 #else
 		printk(BIOS_DEBUG, "Resume from S3 detected, but disabled.\n");
+		wake_from_s3 = 0;
 #endif
 	}
 
+	/* There are hard coded assumptions of 2 meaning s3 wake. Normalize
+	 * the users of the 2 literal here based off wake_from_s3. */
+	boot_mode = wake_from_s3 ? 2 : 0;
+
 	/* Prepare USB controller early in S3 resume */
-	if (boot_mode == 2)
+	if (wake_from_s3)
 		enable_usb_bar();
 
 	post_code(0x3a);
@@ -246,37 +252,25 @@ void romstage_common(const struct romstage_params *params)
 #endif
 
 	/* Save data returned from MRC on non-S3 resumes. */
-	if (boot_mode != 2)
+	if (!wake_from_s3)
 		save_mrc_data(params->pei_data);
 
 #if CONFIG_HAVE_ACPI_RESUME
-	/* If there is no high memory area, we didn't boot before, so
-	 * this is not a resume. In that case we just create the cbmem toc.
-	 */
-
-	*(u32 *)CBMEM_BOOT_MODE = 0;
-	*(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) {
+	if (wake_from_s3 && !cbmem_was_initted) {
 		/* Failed S3 resume, reset to come up cleanly */
 		outb(0x6, 0xcf9);
 		while (1) {
 			hlt();
 		}
-	} else {
-		pci_write_config32(PCI_DEV(0, 0x00, 0), SKPAD, 0xcafebabe);
 	}
 #endif
+
+	handoff = romstage_handoff_find_or_add();
+	if (handoff != NULL)
+		handoff->s3_resume = wake_from_s3;
+	else
+		printk(BIOS_DEBUG, "Romstage handoff structure not added!\n");
+
 	post_code(0x3f);
 #if CONFIG_CHROMEOS
 	init_chromeos(boot_mode);
@@ -295,11 +289,14 @@ 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
+	struct romstage_handoff *handoff = romstage_handoff_find_or_add();
+
 	/* Back up the OS-controlled memory where ramstage will be loaded. */
-	if (*(u32 *)CBMEM_BOOT_MODE == 2) {
+	if (handoff != NULL && handoff->s3_resume) {
 		void *src = (void *)CONFIG_RAMBASE;
-		void *dest = *(void **)CBMEM_RESUME_BACKUP;
-		memcpy(dest, src, HIGH_MEMORY_SAVE);
+		void *dest = cbmem_find(CBMEM_ID_RESUME);
+		if (dest != NULL)
+			memcpy(dest, src, HIGH_MEMORY_SAVE);
 	}
 #endif
 #endif
diff --git a/src/northbridge/intel/haswell/northbridge.c b/src/northbridge/intel/haswell/northbridge.c
index 23bbd29129..87081385b5 100644
--- a/src/northbridge/intel/haswell/northbridge.c
+++ b/src/northbridge/intel/haswell/northbridge.c
@@ -35,6 +35,7 @@
 #include <cpu/x86/smm.h>
 #include <boot/tables.h>
 #include <cbmem.h>
+#include <romstage_handoff.h>
 #include "chip.h"
 #include "haswell.h"
 
@@ -560,19 +561,19 @@ int cbmem_get_table_location(uint64_t *tables_base, uint64_t *tables_size)
 static void northbridge_enable(device_t dev)
 {
 #if CONFIG_HAVE_ACPI_RESUME
-	switch (pci_read_config32(dev, SKPAD)) {
-	case 0xcafebabe:
-		printk(BIOS_DEBUG, "Normal boot.\n");
-		acpi_slp_type=0;
-		break;
-	case 0xcafed00d:
-		printk(BIOS_DEBUG, "S3 Resume.\n");
-		acpi_slp_type=3;
-		break;
-	default:
+	struct romstage_handoff *handoff;
+
+	handoff = cbmem_find(CBMEM_ID_ROMSTAGE_INFO);
+
+	if (handoff == NULL) {
 		printk(BIOS_DEBUG, "Unknown boot method, assuming normal.\n");
-		acpi_slp_type=0;
-		break;
+		acpi_slp_type = 0;
+	} else if (handoff->s3_resume) {
+		printk(BIOS_DEBUG, "S3 Resume.\n");
+		acpi_slp_type = 3;
+	} else {
+		printk(BIOS_DEBUG, "Normal boot.\n");
+		acpi_slp_type = 0;
 	}
 #endif
 }