libpayload: Add support for handling fmaps

They will become more common soon, so better support them now.

Change-Id: I2b16e1bb7707fe8410365877524ff359aeefc161
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: http://review.coreboot.org/10868
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

payloads/libpayload/include/fmap_serialized.h

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2010, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *    * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *    * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *    * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ */
+
+#ifndef FLASHMAP_SERIALIZED_H__
+#define FLASHMAP_SERIALIZED_H__
+
+#include <stdint.h>
+
+#define FMAP_SIGNATURE		"__FMAP__"
+#define FMAP_VER_MAJOR		1	/* this header's FMAP minor version */
+#define FMAP_VER_MINOR		1	/* this header's FMAP minor version */
+#define FMAP_STRLEN		32	/* maximum length for strings, */
+					/* including null-terminator */
+
+enum fmap_flags {
+	FMAP_AREA_STATIC	= 1 << 0,
+	FMAP_AREA_COMPRESSED	= 1 << 1,
+	FMAP_AREA_RO		= 1 << 2,
+};
+
+/* Mapping of volatile and static regions in firmware binary */
+struct fmap_area {
+	uint32_t offset;                /* offset relative to base */
+	uint32_t size;                  /* size in bytes */
+	uint8_t  name[FMAP_STRLEN];     /* descriptive name */
+	uint16_t flags;                 /* flags for this area */
+}  __attribute__((packed));
+
+struct fmap {
+	uint8_t  signature[8];		/* "__FMAP__" (0x5F5F464D41505F5F) */
+	uint8_t  ver_major;		/* major version */
+	uint8_t  ver_minor;		/* minor version */
+	uint64_t base;			/* address of the firmware binary */
+	uint32_t size;			/* size of firmware binary in bytes */
+	uint8_t  name[FMAP_STRLEN];	/* name of this firmware binary */
+	uint16_t nareas;		/* number of areas described by
+					   fmap_areas[] below */
+	struct fmap_area areas[];
+} __attribute__((packed));
+
+#endif	/* FLASHMAP_SERIALIZED_H__ */

payloads/libpayload/include/libpayload.h

@@ -47,6 +47,7 @@
 #include <ctype.h>
 #include <die.h>
 #include <endian.h>
+#include <fmap_serialized.h>
 #include <ipchksum.h>
 #include <kconfig.h>
 #include <stddef.h>
@@ -405,4 +406,8 @@ void gdb_enter(void);
 /* Disconnect existing GDB connection if one exists. */
 void gdb_exit(s8 exit_status);
 
+/* look for area "name" in "fmap", setting offset and size to describe it.
+   Returns 0 on success, < 0 on error. */
+int fmap_region_by_name(const uint32_t fmap_offset, const char * const name,
+			uint32_t * const offset, uint32_t * const size);
 #endif

payloads/libpayload/libc/Makefile.inc

@@ -38,6 +38,7 @@ libc-$(CONFIG_LP_LIBC) += qsort.c
 libc-$(CONFIG_LP_LIBC) += hexdump.c
 libc-$(CONFIG_LP_LIBC) += die.c
 libc-$(CONFIG_LP_LIBC) += coreboot.c
+libc-$(CONFIG_LP_LIBC) += fmap.c
 
 ifeq ($(CONFIG_LP_ARCH_MIPS),y)
 libc-$(CONFIG_LP_LIBC) += 64bit_div.c

payloads/libpayload/libc/fmap.c

@@ -0,0 +1,84 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2015 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <libpayload-config.h>
+#include <libpayload.h>
+#include <coreboot_tables.h>
+#include <cbfs.h>
+#include <fmap_serialized.h>
+#include <stdint.h>
+
+int fmap_region_by_name(const uint32_t fmap_offset, const char * const name,
+			uint32_t * const offset, uint32_t * const size)
+{
+	int i;
+
+	struct fmap *fmap;
+	struct fmap fmap_head;
+	struct cbfs_media default_media;
+	struct cbfs_media *media = &default_media;
+
+	if (init_default_cbfs_media(media) != 0)
+		return -1;
+
+	media->open(media);
+
+	if (!media->read(media, &fmap_head, fmap_offset, sizeof(fmap_head)))
+		return -1;
+
+	if (memcmp(fmap_head.signature, FMAP_SIGNATURE, sizeof(fmap_head.signature))) {
+		return -1;
+	}
+
+	int fmap_size = sizeof(*fmap) +
+		fmap_head.nareas * sizeof(struct fmap_area);
+
+	fmap = malloc(fmap_size);
+	if (!fmap)
+		return -1;
+
+	if (!media->read(media, fmap, fmap_offset, fmap_size))
+		goto err;
+
+	media->close(media);
+
+	for (i = 0; i < fmap->nareas; i++) {
+		if (strcmp((const char *)fmap->areas[i].name, name) != 0)
+			continue;
+		if (offset)
+			*offset = fmap->areas[i].offset;
+		if (size)
+			*size = fmap->areas[i].size;
+		free(fmap);
+		return 0;
+	}
+err:
+	free(fmap);
+	return -1;
+}