coreboot-kgpe-d16/payloads/libpayload/i386/coreboot.c

/*
 * This file is part of the libpayload project.
 *
 * Copyright (C) 2008 Advanced Micro Devices, 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.h>
#include <sysinfo.h>
#include <coreboot_tables.h>

/* Some of this is x86 specific, and the rest of it
   is generic.  Right now, since we only support x86,
   we'll avoid trying to make lots of infrastructure
   we don't need.  If in the future, we want to use
   coreboot on some other architecture, then take out
   the generic parsing code and move it elsewhere
*/

/* === Parsing code === */
/* This is the generic parsing code */

static void cb_parse_memory(unsigned char *ptr, struct sysinfo_t *info)
{
	struct cb_memory *mem = (struct cb_memory *) ptr;
	int count = MEM_RANGE_COUNT(mem);
	int i;

	if (count > SYSINFO_MAX_MEM_RANGES)
		count = SYSINFO_MAX_MEM_RANGES;

	info->n_memranges = 0;

	for(i = 0; i < count; i++) {
		struct cb_memory_range *range = 
			(struct cb_memory_range *) MEM_RANGE_PTR(mem, i);
		
		if (range->type != CB_MEM_RAM)
			continue;

		info->memrange[info->n_memranges].base =
			UNPACK_CB64(range->start);

		info->memrange[info->n_memranges].size =
			UNPACK_CB64(range->size);

		info->n_memranges++;
	}
}

static void cb_parse_serial(unsigned char *ptr, struct sysinfo_t *info)
{
	struct cb_serial *ser = (struct cb_serial *) ptr;
	info->ser_ioport = ser->ioport;
}

static int cb_parse_header(void *addr, int len, struct sysinfo_t *info)
{
	struct cb_header *header;
	unsigned char *ptr = (unsigned char *) addr;
	int i;

	for (i = 0; i < len; i += 16, ptr += 16) {
		header = (struct cb_header *) ptr;

		if (!strncmp(header->signature, "LBIO", 4))
			break;
	}
	
	/* We walked the entire space and didn't find anything */

	if (i >= len)
		return -1;

	if (!header->table_bytes)
		return 0;

	/* Make sure the checksums match */

	if (ipchksum((uint16_t *) header, sizeof(*header)) != 0)
		return -1;

	if (ipchksum((uint16_t *) (ptr + sizeof(*header)),
		header->table_bytes) != header->table_checksum)
		return -1;

	/* Now, walk the tables */
	ptr += header->header_bytes;
    
	for(i = 0; i < header->table_entries; i++) {
		struct cb_record *rec = (struct cb_record *) ptr;

		/* We only care about a few tags here - maybe
		   more will be interesting later 
		*/

 		switch(rec->tag) {
		case CB_TAG_MEMORY:
			cb_parse_memory(ptr, info);
			break;
			
		case CB_TAG_SERIAL:
			cb_parse_serial(ptr, info);
			break;
		}

		ptr += rec->size;
	}
	
	return 1;
}

/* == Architecture specific ==*/
/* This is the x86 specific stuff */

int get_coreboot_info(struct sysinfo_t *info)
{
	int ret = cb_parse_header((void *) 0x0, 0x1000, info);

	if (ret != 1)
		ret = cb_parse_header((void *) 0xf0000, 0x1000, info);

	return (ret == 1) ? 0 : -1;
}