coreboot: config to cache ramstage outside CBMEM

Haswell was the original chipset to store the cache
in another area besides CBMEM. However, it was specific
to the implementation. Instead, provide a generic way
to obtain the location of the ramstage cache. This option
is selected using the CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
Kconfig option.

BUG=chrome-os-partner:23249
BRANCH=None
TEST=Built and booted with baytrail support. Also built for
     falco successfully.

Change-Id: I70d0940f7a8f73640c92a75fd22588c2c234241b
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/172602
Reviewed-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/4876
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

3 files changed, 146 insertions, 47 deletions

diff --git a/src/lib/Makefile.inc b/src/lib/Makefile.inc
index 37c7dea2ec..18b30efefa 100644
--- a/src/lib/Makefile.inc
+++ b/src/lib/Makefile.inc
@@ -119,6 +119,8 @@ romstage-y += hexdump.c
 
 ramstage-$(CONFIG_CONSOLE_NE2K) += ne2k.c
 
+romstage-$(CONFIG_CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM) += ramstage_cache.c
+
 ifneq ($(CONFIG_HAVE_ARCH_MEMSET),y)
 smm-y += memset.c
 endif
diff --git a/src/lib/cbfs.c b/src/lib/cbfs.c
index d101f452ec..9fe1757a65 100644
--- a/src/lib/cbfs.c
+++ b/src/lib/cbfs.c
@@ -127,53 +127,6 @@ void *cbfs_load_optionrom(struct cbfs_media *media, uint16_t vendor,
 
 #include <rmodule.h>
 #include <romstage_handoff.h>
-/* When CONFIG_RELOCATABLE_RAMSTAGE is enabled and this file is being compiled
- * for the romstage, the rmodule loader is used.  */
-void __attribute__((weak))
-cache_loaded_ramstage(struct romstage_handoff *handoff,
-                      const struct cbmem_entry *ramstage, void *entry_point)
-{
-	uint32_t ramstage_size;
-	const struct cbmem_entry *entry;
-
-	if (handoff == NULL)
-		return;
-
-	ramstage_size = cbmem_entry_size(ramstage);
-	/* cbmem_entry_add() does a find() before add(). */
-	entry = cbmem_entry_add(CBMEM_ID_RAMSTAGE_CACHE, ramstage_size);
-
-	if (entry == NULL)
-		return;
-
-	/* Keep track of the entry point in the handoff structure. */
-	handoff->ramstage_entry_point = (uint32_t)entry_point;
-
-	memcpy(cbmem_entry_start(entry), cbmem_entry_start(ramstage),
-	       ramstage_size);
-}
-
-void * __attribute__((weak))
-load_cached_ramstage(struct romstage_handoff *handoff,
-                     const struct cbmem_entry *ramstage)
-{
-	const struct cbmem_entry *entry_cache;
-
-	if (handoff == NULL)
-		return NULL;
-
-	entry_cache = cbmem_entry_find(CBMEM_ID_RAMSTAGE_CACHE);
-
-	if (entry_cache == NULL)
-		return NULL;
-
-	/* Load the cached ramstage copy into the to-be-run region. */
-	memcpy(cbmem_entry_start(ramstage), cbmem_entry_start(entry_cache),
-	       cbmem_entry_size(ramstage));
-
-	return (void *)handoff->ramstage_entry_point;
-}
-
 static void *load_stage_from_cbfs(struct cbfs_media *media, const char *name,
                                   struct romstage_handoff *handoff)
 {
diff --git a/src/lib/ramstage_cache.c b/src/lib/ramstage_cache.c
new file mode 100644
index 0000000000..a1a4804a16
--- /dev/null
+++ b/src/lib/ramstage_cache.c
@@ -0,0 +1,144 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stddef.h>
+#include <string.h>
+#include <cbfs.h>
+#include <console/console.h>
+#include <ramstage_cache.h>
+#include <romstage_handoff.h>
+
+#if CONFIG_CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
+
+void cache_loaded_ramstage(struct romstage_handoff *handoff,
+                           const struct cbmem_entry *ramstage,
+                           void *entry_point)
+{
+	struct ramstage_cache *cache;
+	uint32_t total_size;
+	uint32_t ramstage_size;
+	void *ramstage_base;
+	long cache_size = 0;
+
+	ramstage_size = cbmem_entry_size(ramstage);
+	ramstage_base = cbmem_entry_start(ramstage);
+
+	cache = ramstage_cache_location(&cache_size);
+
+	if (cache == NULL) {
+		printk(BIOS_DEBUG, "No ramstage cache location provided.\n");
+		return;
+	}
+
+	total_size = sizeof(*cache) + ramstage_size;
+	if (total_size > cache_size) {
+		printk(BIOS_DEBUG, "cache size too small: 0x%08x > 0x%08lx\n",
+		       total_size, cache_size);
+		/* Nuke whatever may be there now just in case. */
+		cache->magic = ~RAMSTAGE_CACHE_MAGIC;
+		return;
+	}
+
+	cache->magic = RAMSTAGE_CACHE_MAGIC;
+	cache->entry_point = (uint32_t)entry_point;
+	cache->load_address = (uint32_t)ramstage_base;
+	cache->size = ramstage_size;
+
+	printk(BIOS_DEBUG, "Saving ramstage to %p.\n", cache);
+
+	/* Copy over the program. */
+	memcpy(&cache->program[0], ramstage_base, ramstage_size);
+
+	if (handoff == NULL)
+		return;
+
+	handoff->ramstage_entry_point = (uint32_t)entry_point;
+}
+
+void *load_cached_ramstage(struct romstage_handoff *handoff,
+                           const struct cbmem_entry *ramstage)
+{
+	struct ramstage_cache *cache;
+	long size = 0;
+
+	cache = ramstage_cache_location(&size);
+
+	if (cache == NULL || cache->magic != RAMSTAGE_CACHE_MAGIC) {
+		printk(BIOS_DEBUG, "Invalid ramstage cache found.\n");
+		ramstage_cache_invalid(cache);
+		return NULL;
+	}
+
+	printk(BIOS_DEBUG, "Loading ramstage from %p.\n", cache);
+
+	memcpy((void *)cache->load_address, &cache->program[0], cache->size);
+
+	return (void *)cache->entry_point;
+}
+
+#else
+
+/* Cache relocated ramstage in CBMEM. */
+
+void __attribute__((weak))
+cache_loaded_ramstage(struct romstage_handoff *handoff,
+                      const struct cbmem_entry *ramstage, void *entry_point)
+{
+	uint32_t ramstage_size;
+	const struct cbmem_entry *entry;
+
+	if (handoff == NULL)
+		return;
+
+	ramstage_size = cbmem_entry_size(ramstage);
+	/* cbmem_entry_add() does a find() before add(). */
+	entry = cbmem_entry_add(CBMEM_ID_RAMSTAGE_CACHE, ramstage_size);
+
+	if (entry == NULL)
+		return;
+
+	/* Keep track of the entry point in the handoff structure. */
+	handoff->ramstage_entry_point = (uint32_t)entry_point;
+
+	memcpy(cbmem_entry_start(entry), cbmem_entry_start(ramstage),
+	       ramstage_size);
+}
+
+void * __attribute__((weak))
+load_cached_ramstage(struct romstage_handoff *handoff,
+                     const struct cbmem_entry *ramstage)
+{
+	const struct cbmem_entry *entry_cache;
+
+	if (handoff == NULL)
+		return NULL;
+
+	entry_cache = cbmem_entry_find(CBMEM_ID_RAMSTAGE_CACHE);
+
+	if (entry_cache == NULL)
+		return NULL;
+
+	/* Load the cached ramstage copy into the to-be-run region. */
+	memcpy(cbmem_entry_start(ramstage), cbmem_entry_start(entry_cache),
+	       cbmem_entry_size(ramstage));
+
+	return (void *)handoff->ramstage_entry_point;
+}
+
+#endif