cbfstool: Add update-fit command

Add support for filling in the Firmware Interface Table.
For now it only supports adding microcode entries.

It takes 2 options:
1. Name of file in cbfs where the mircocode is located
2. The number of empty entries in the table.

Verified with go firmware tools. Also commented out updating
microcode in the bootblock. When romstage runs, the CPUs indicate
their microcode is already loaded.

Change-Id: Iaccaa9c226ee24868a5f4c0ba79729015d15bbef
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2712
Reviewed-by: Aaron Durbin <adurbin@google.com>
Tested-by: build bot (Jenkins)

1 files changed, 277 insertions, 0 deletions

diff --git a/util/cbfstool/fit.c b/util/cbfstool/fit.c
new file mode 100644
index 0000000000..12a7e3b49f
--- /dev/null
+++ b/util/cbfstool/fit.c
@@ -0,0 +1,277 @@
+/*
+ * Firmware Interface Table support.
+ *
+ * Copyright (C) 2012 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 <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "common.h"
+#include "cbfs.h"
+#include "cbfs_image.h"
+#include "fit.h"
+
+/* FIXME: This code assumes it is being executed on a little endian machine. */
+
+#define FIT_POINTER_LOCATION 0xffffffc0
+#define FIT_TABLE_LOWEST_ADDRESS ((uint32_t)(-(16 << 20)))
+#define FIT_ENTRY_CHECKSUM_VALID 0x80
+#define FIT_TYPE_HEADER 0x0
+#define   FIT_HEADER_VERSION 0x0100
+#define   FIT_HEADER_ADDRESS "_FIT_   "
+#define FIT_TYPE_MICROCODE 0x1
+#define   FIT_MICROCODE_VERSION 0x0100
+
+struct fit_entry {
+	uint64_t address;
+	uint32_t size_reserved;
+	uint16_t version;
+	uint8_t  type_checksum_valid;
+	uint8_t  checksum;
+} __attribute__ ((packed));
+
+struct fit_table {
+	struct fit_entry header;
+	struct fit_entry entries[0];
+} __attribute__ ((packed));
+
+struct microcode_header {
+	uint32_t version;
+	uint32_t revision;
+	uint32_t date;
+	uint32_t processor_signature;
+	uint32_t checksum;
+	uint32_t loader_revision;
+	uint32_t processor_flags;
+	uint32_t data_size;
+	uint32_t total_size;
+	uint8_t  reserved[12];
+} __attribute__ ((packed));
+
+struct microcode_entry {
+	int offset;
+	int size;
+};
+
+static inline void *rom_buffer_pointer(struct cbfs_image *image, int offset)
+{
+	return &image->buffer.data[offset];
+}
+
+static inline int fit_entry_size_bytes(struct fit_entry *entry)
+{
+	return (entry->size_reserved & 0xffffff) << 4;
+}
+
+static inline void fit_entry_update_size(struct fit_entry *entry,
+					 int size_bytes)
+{
+	/* Size is multiples of 16 bytes. */
+	entry->size_reserved = (size_bytes >> 4) & 0xffffff;
+}
+
+static inline void fit_entry_add_size(struct fit_entry *entry,
+                                      int size_bytes)
+{
+	int size = fit_entry_size_bytes(entry);
+	size += size_bytes;
+	fit_entry_update_size(entry, size);
+}
+
+static inline int fit_entry_type(struct fit_entry *entry)
+{
+	return entry->type_checksum_valid & ~FIT_ENTRY_CHECKSUM_VALID;
+}
+
+/*
+ * Get an offset from a host pointer. This function assumes the ROM is located
+ * in the host address space at [4G - romsize -> 4G). It also assume all
+ * pointers have values within this address range.
+ */
+static inline int ptr_to_offset(uint32_t romsize, uint32_t host_ptr)
+{
+	return (int)(romsize + host_ptr);
+}
+
+/*
+ * Get a pointer from an offset. This function assumes the ROM is located
+ * in the host address space at [4G - romsize -> 4G). It also assume all
+ * pointers have values within this address range.
+ */
+static inline uint32_t offset_to_ptr(uint32_t romsize, int offset)
+{
+	return -(romsize - (uint32_t )offset);
+}
+
+static struct fit_table *locate_fit_table(struct cbfs_image *image)
+{
+	struct fit_table *table;
+	uint32_t *fit_pointer;
+
+	fit_pointer = rom_buffer_pointer(image,
+                              ptr_to_offset(image->buffer.size, FIT_POINTER_LOCATION));
+
+	/* Ensure pointer is below 4GiB and within 16MiB of 4GiB */
+	if (fit_pointer[1] != 0 || fit_pointer[0] < FIT_TABLE_LOWEST_ADDRESS)
+		return NULL;
+
+	table = rom_buffer_pointer(image,
+	                           ptr_to_offset(image->buffer.size, *fit_pointer));
+
+	/* Check that the address field has the proper signature. */
+	if (strncmp((const char *)&table->header.address, FIT_HEADER_ADDRESS,
+	            sizeof(table->header.address)))
+		return NULL;
+
+	if (table->header.version != FIT_HEADER_VERSION)
+		return NULL;
+
+	if (fit_entry_type(&table->header) != FIT_TYPE_HEADER)
+		return NULL;
+
+	/* Assume that the FIT table only contains the header */
+	if (fit_entry_size_bytes(&table->header) != sizeof(struct fit_entry))
+		return NULL;
+
+	return table;
+}
+
+static void update_fit_checksum(struct fit_table *fit)
+{
+	int size_bytes;
+	uint8_t *buffer;
+	uint8_t result;
+	int i;
+
+	fit->header.checksum = 0;
+	size_bytes = fit_entry_size_bytes(&fit->header);
+	result = 0;
+	buffer = (void *)fit;
+	for (i = 0; i < size_bytes; i++)
+		result += buffer[i];
+	fit->header.checksum = -result;
+}
+
+static void add_microcodde_entries(struct cbfs_image *image,
+                                   struct fit_table *fit,
+                                   struct microcode_entry *mcus, int num_mcus)
+{
+	int i;
+
+	for (i = 0; i < num_mcus; i++) {
+		struct fit_entry *entry = &fit->entries[i];
+		struct microcode_entry *mcu = &mcus[i];
+
+		entry->address = offset_to_ptr(image->buffer.size, mcu->offset);
+		fit_entry_update_size(entry, mcu->size);
+		entry->version = FIT_MICROCODE_VERSION;
+		entry->type_checksum_valid = FIT_TYPE_MICROCODE;
+		entry->checksum = 0;
+		fit_entry_add_size(&fit->header, sizeof(struct fit_entry));
+	}
+}
+
+static int parse_microcode_blob(struct cbfs_image *image,
+                                struct cbfs_file *mcode_file,
+                                struct microcode_entry *mcus, int *total_mcus)
+{
+	int num_mcus;
+	int current_offset;
+	int file_length;
+
+	current_offset = (int)((char *)mcode_file - image->buffer.data);
+	current_offset += ntohl(mcode_file->offset);
+	file_length = ntohl(mcode_file->len);
+
+	num_mcus = 0;
+	while (file_length > sizeof(struct microcode_header))
+	{
+		struct microcode_header *mcu_header;
+
+		mcu_header = rom_buffer_pointer(image, current_offset);
+
+		/* FIXME: Should the checksum be validated? */
+		mcus[num_mcus].offset = current_offset;
+		mcus[num_mcus].size = mcu_header->total_size;
+
+		/* Proceed to next payload. */
+		current_offset += mcus[num_mcus].size;
+		num_mcus++;
+		file_length -= mcus[num_mcus].size;
+
+		/* Can't determine any more entries. */
+		if (!mcu_header->total_size)
+			break;
+
+		/* Reached limit of FIT entries. */
+		if (num_mcus == *total_mcus)
+			break;
+		if (file_length < sizeof(struct microcode_header))
+			break;
+	}
+
+	/* Update how many microcode updates we found. */
+	*total_mcus = num_mcus;
+
+	return 0;
+}
+
+int fit_update_table(struct cbfs_image *image, int empty_entries,
+                     const char *microcode_blob_name)
+{
+	struct fit_table *fit;
+	struct cbfs_file *mcode_file;
+	struct microcode_entry *mcus;
+	int ret = 0;
+	// struct rom_image image = { .rom = rom, .size = romsize, };
+
+	fit = locate_fit_table(image);
+
+	if (!fit) {
+		ERROR("FIT not found.\n");
+		return 1;
+	}
+
+	mcode_file = cbfs_get_entry(image, microcode_blob_name);
+	if (!mcode_file) {
+		ERROR("File '%s' not found in CBFS.\n",
+		        microcode_blob_name);
+		return 1;
+	}
+
+	mcus = malloc(sizeof(*mcus) * empty_entries);
+
+	if (!mcus) {
+		ERROR("Couldn't allocate memory for microcode update entries.\n");
+		return 1;
+	}
+
+	if (parse_microcode_blob(image, mcode_file, mcus, &empty_entries)) {
+		ERROR("Couldn't parse microcode blob.\n");
+		ret = 1;
+		goto out;
+	}
+
+	add_microcodde_entries(image, fit, mcus, empty_entries);
+	update_fit_checksum(fit);
+
+out:
+	free(mcus);
+	return ret;
+}