libpayload/libc/fmap: Implement new FlashMap API

This patch introduces new FlashMap API, the fmap_locate_area().
It works on cached FlashMap provided in lib_sysinfo.fmap_cache.

Change-Id: Idbf9016ce73aa58e17f3ee19920ab83dc6c25abb
Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59494
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

6 files changed, 180 insertions, 76 deletions

diff --git a/payloads/libpayload/include/fmap.h b/payloads/libpayload/include/fmap.h
new file mode 100644
index 0000000000..53ebe23dcb
--- /dev/null
+++ b/payloads/libpayload/include/fmap.h
@@ -0,0 +1,12 @@
+/* SPDX_License-Identifier: BSD-3-Clause */
+
+#ifndef _FMAP_H
+#define _FMAP_H
+
+#include <commonlib/bsd/cb_err.h>
+#include <stddef.h>
+
+/* Looks for area with |name| in FlashMap. Requires lib_sysinfo.fmap_cache. */
+cb_err_t fmap_locate_area(const char *name, size_t *offset, size_t *size);
+
+#endif /* _FMAP_H */
diff --git a/payloads/libpayload/include/fmap_serialized.h b/payloads/libpayload/include/fmap_serialized.h
deleted file mode 100644
index 53a09af7a8..0000000000
--- a/payloads/libpayload/include/fmap_serialized.h
+++ /dev/null
@@ -1,74 +0,0 @@
-/*
- * 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,
-	FMAP_AREA_PRESERVE	= 1 << 3,
-};
-
-/* 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 */
-}  __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[];
-} __packed;
-
-#endif	/* FLASHMAP_SERIALIZED_H__ */
diff --git a/payloads/libpayload/include/libpayload.h b/payloads/libpayload/include/libpayload.h
index 389571071a..8d8336f559 100644
--- a/payloads/libpayload/include/libpayload.h
+++ b/payloads/libpayload/include/libpayload.h
@@ -45,10 +45,11 @@
 #include <stdbool.h>
 #include <libpayload-config.h>
 #include <cbgfx.h>
+#include <commonlib/bsd/fmap_serialized.h>
 #include <ctype.h>
 #include <die.h>
 #include <endian.h>
-#include <fmap_serialized.h>
+#include <fmap.h>
 #include <ipchksum.h>
 #include <kconfig.h>
 #include <stddef.h>
diff --git a/payloads/libpayload/libc/fmap.c b/payloads/libpayload/libc/fmap.c
index b7d64918ac..2d185a7c60 100644
--- a/payloads/libpayload/libc/fmap.c
+++ b/payloads/libpayload/libc/fmap.c
@@ -28,10 +28,60 @@
 
 #include <libpayload-config.h>
 #include <libpayload.h>
+#include <commonlib/bsd/fmap_serialized.h>
 #include <coreboot_tables.h>
 #include <cbfs.h>
-#include <fmap_serialized.h>
+#include <boot_device.h>
 #include <stdint.h>
+#include <arch/virtual.h>
+
+/* Private fmap cache. */
+static struct fmap *_fmap_cache;
+
+static cb_err_t fmap_find_area(struct fmap *fmap, const char *name, size_t *offset,
+			       size_t *size)
+{
+	for (size_t i = 0; i < le32toh(fmap->nareas); ++i) {
+		if (strncmp((const char *)fmap->areas[i].name, name, FMAP_STRLEN) != 0)
+			continue;
+		if (offset)
+			*offset = le32toh(fmap->areas[i].offset);
+		if (size)
+			*size = le32toh(fmap->areas[i].size);
+		return CB_SUCCESS;
+	}
+
+	return CB_ERR;
+}
+
+static bool fmap_is_signature_valid(struct fmap *fmap)
+{
+	return memcmp(fmap->signature, FMAP_SIGNATURE, sizeof(fmap->signature)) == 0;
+}
+
+static bool fmap_setup_cache(void)
+{
+	/* Use FMAP cache if available */
+	if (lib_sysinfo.fmap_cache
+	    && fmap_is_signature_valid((struct fmap *)phys_to_virt(lib_sysinfo.fmap_cache))) {
+		_fmap_cache = (struct fmap *)phys_to_virt(lib_sysinfo.fmap_cache);
+		return true;
+	}
+
+	return false;
+}
+
+cb_err_t fmap_locate_area(const char *name, size_t *offset, size_t *size)
+{
+	if (!_fmap_cache && !fmap_setup_cache())
+		return CB_ERR;
+
+	return fmap_find_area(_fmap_cache, name, offset, size);
+}
+
+/***********************************************************************************************
+ *                                         LEGACY CODE                                         *
+ **********************************************************************************************/
 
 int fmap_region_by_name(const uint32_t fmap_offset, const char * const name,
 			uint32_t * const offset, uint32_t * const size)
diff --git a/payloads/libpayload/tests/libc/Makefile.inc b/payloads/libpayload/tests/libc/Makefile.inc
new file mode 100644
index 0000000000..5f92bdf0a8
--- /dev/null
+++ b/payloads/libpayload/tests/libc/Makefile.inc
@@ -0,0 +1,3 @@
+tests-y += fmap_locate_area-test
+
+fmap_locate_area-test-srcs += tests/libc/fmap_locate_area-test.c
diff --git a/payloads/libpayload/tests/libc/fmap_locate_area-test.c b/payloads/libpayload/tests/libc/fmap_locate_area-test.c
new file mode 100644
index 0000000000..ce7c36b373
--- /dev/null
+++ b/payloads/libpayload/tests/libc/fmap_locate_area-test.c
@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include "../libc/fmap.c"
+
+#include <libpayload.h>
+#include <tests/test.h>
+
+
+/* Mocks */
+struct sysinfo_t lib_sysinfo;
+unsigned long virtual_offset = 0;
+
+static void reset_fmap_cache(void)
+{
+	_fmap_cache = NULL;
+}
+
+static int setup_fmap_test(void **state)
+{
+	reset_fmap_cache();
+	lib_sysinfo.fmap_cache = 0;
+	return 0;
+}
+
+static void test_fmap_locate_area_no_fmap_available(void **state)
+{
+	size_t offset = 0;
+	size_t size = 0;
+
+	assert_int_equal(-1, fmap_locate_area("COREBOOT", &offset, &size));
+}
+
+static void test_fmap_locate_area_incorrect_signature(void **state)
+{
+	size_t offset = 0;
+	size_t size = 0;
+	struct fmap mock_fmap = {
+		.signature = "NOT_MAP",
+	};
+	lib_sysinfo.fmap_cache = (uintptr_t)&mock_fmap;
+
+	assert_int_equal(-1, fmap_locate_area("COREBOOT", &offset, &size));
+}
+
+static void test_fmap_locate_area_success(void **state)
+{
+	size_t offset = 0;
+	size_t size = 0;
+	struct fmap mock_fmap = {
+		.signature = FMAP_SIGNATURE,
+		.ver_major = 1,
+		.ver_minor = 1,
+		.base = 0xAABB,
+		.size = 0x10000,
+		.nareas = 3,
+	};
+	struct fmap_area area_1 = {
+		.size = 0x1100,
+		.offset = 0x11,
+		.name = {'F', 'I', 'R', 'S', 'T', '_', 'A', 'R', 'E', 'A', 0},
+		.flags = 0,
+	};
+	struct fmap_area area_2 = {
+		.size = 0x2200,
+		.offset = 0x1111,
+		.name = {'S', 'E', 'C', 'O', 'N', 'D', '_', 'A', 'R', 'E', 'A', 0},
+		.flags = 0,
+	};
+	struct fmap_area area_3 = {
+		.size = 0x100,
+		.offset = 0x3311,
+		.name = {'T', 'H', 'I', 'R', 'D', '_', 'A', 'R', 'E', 'A', 0},
+		.flags = 0,
+	};
+	u8 fmap_buffer[sizeof(struct fmap) + 3 * sizeof(struct fmap_area)];
+	memcpy(fmap_buffer, &mock_fmap, sizeof(mock_fmap));
+	memcpy(&fmap_buffer[sizeof(mock_fmap)], &area_1, sizeof(area_1));
+	memcpy(&fmap_buffer[sizeof(mock_fmap) + sizeof(area_1)], &area_2, sizeof(area_2));
+	memcpy(&fmap_buffer[sizeof(mock_fmap) + sizeof(area_1) + sizeof(area_2)], &area_3,
+	       sizeof(area_3));
+
+	/* Cache only */
+	reset_fmap_cache();
+	lib_sysinfo.fmap_cache = (uintptr_t)fmap_buffer;
+
+	assert_int_equal(0, fmap_locate_area("FIRST_AREA", &offset, &size));
+	assert_int_equal(area_1.offset, offset);
+	assert_int_equal(area_1.size, size);
+
+	assert_int_equal(0, fmap_locate_area("THIRD_AREA", &offset, &size));
+	assert_int_equal(area_3.offset, offset);
+	assert_int_equal(area_3.size, size);
+
+	assert_int_equal(0, fmap_locate_area("SECOND_AREA", &offset, &size));
+	assert_int_equal(area_2.offset, offset);
+	assert_int_equal(area_2.size, size);
+
+	reset_fmap_cache();
+}
+
+#define FMAP_LOCATE_AREA_TEST(fn) cmocka_unit_test_setup(fn, setup_fmap_test)
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		FMAP_LOCATE_AREA_TEST(test_fmap_locate_area_no_fmap_available),
+		FMAP_LOCATE_AREA_TEST(test_fmap_locate_area_incorrect_signature),
+		FMAP_LOCATE_AREA_TEST(test_fmap_locate_area_success),
+	};
+
+	return lp_run_group_tests(tests, NULL, NULL);
+}