source: trunk/spi.c @ 1475

/*
 * This file is part of the flashrom project.
 *
 * Copyright (C) 2007, 2008, 2009, 2010, 2011 Carl-Daniel Hailfinger
 * Copyright (C) 2008 coresystems GmbH
 *
 * 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
 */

/*
 * Contains the generic SPI framework
 */

#include <strings.h>
#include <string.h>
#include "flash.h"
#include "flashchips.h"
#include "chipdrivers.h"
#include "programmer.h"
#include "spi.h"

int spi_send_command(struct flashctx *flash, unsigned int writecnt,
                     unsigned int readcnt, const unsigned char *writearr,
                     unsigned char *readarr)
{
        return flash->pgm->spi.command(flash, writecnt, readcnt, writearr,
                                       readarr);
}

int spi_send_multicommand(struct flashctx *flash, struct spi_command *cmds)
{
        return flash->pgm->spi.multicommand(flash, cmds);
}

int default_spi_send_command(struct flashctx *flash, unsigned int writecnt,
                             unsigned int readcnt,
                             const unsigned char *writearr,
                             unsigned char *readarr)
{
        struct spi_command cmd[] = {
        {
                .writecnt = writecnt,
                .readcnt = readcnt,
                .writearr = writearr,
                .readarr = readarr,
        }, {
                .writecnt = 0,
                .writearr = NULL,
                .readcnt = 0,
                .readarr = NULL,
        }};

        return spi_send_multicommand(flash, cmd);
}

int default_spi_send_multicommand(struct flashctx *flash,
                                  struct spi_command *cmds)
{
        int result = 0;
        for (; (cmds->writecnt || cmds->readcnt) && !result; cmds++) {
                result = spi_send_command(flash, cmds->writecnt, cmds->readcnt,
                                          cmds->writearr, cmds->readarr);
        }
        return result;
}

int default_spi_read(struct flashctx *flash, uint8_t *buf, unsigned int start,
                     unsigned int len)
{
        unsigned int max_data = flash->pgm->spi.max_data_read;
        if (max_data == MAX_DATA_UNSPECIFIED) {
                msg_perr("%s called, but SPI read chunk size not defined "
                         "on this hardware. Please report a bug at "
                         "flashrom@flashrom.org\n", __func__);
                return 1;
        }
        return spi_read_chunked(flash, buf, start, len, max_data);
}

int default_spi_write_256(struct flashctx *flash, uint8_t *buf,
                          unsigned int start, unsigned int len)
{
        unsigned int max_data = flash->pgm->spi.max_data_write;
        if (max_data == MAX_DATA_UNSPECIFIED) {
                msg_perr("%s called, but SPI write chunk size not defined "
                         "on this hardware. Please report a bug at "
                         "flashrom@flashrom.org\n", __func__);
                return 1;
        }
        return spi_write_chunked(flash, buf, start, len, max_data);
}

int spi_chip_read(struct flashctx *flash, uint8_t *buf, unsigned int start,
                  unsigned int len)
{
        unsigned int addrbase = 0;

        /* Check if the chip fits between lowest valid and highest possible
         * address. Highest possible address with the current SPI implementation
         * means 0xffffff, the highest unsigned 24bit number.
         */
        addrbase = spi_get_valid_read_addr(flash);
        if (addrbase + flash->total_size * 1024 > (1 << 24)) {
                msg_perr("Flash chip size exceeds the allowed access window. ");
                msg_perr("Read will probably fail.\n");
                /* Try to get the best alignment subject to constraints. */
                addrbase = (1 << 24) - flash->total_size * 1024;
        }
        /* Check if alignment is native (at least the largest power of two which
         * is a factor of the mapped size of the chip).
         */
        if (ffs(flash->total_size * 1024) > (ffs(addrbase) ? : 33)) {
                msg_perr("Flash chip is not aligned natively in the allowed "
                         "access window.\n");
                msg_perr("Read will probably return garbage.\n");
        }
        return flash->pgm->spi.read(flash, buf, addrbase + start, len);
}

/*
 * Program chip using page (256 bytes) programming.
 * Some SPI masters can't do this, they use single byte programming instead.
 * The redirect to single byte programming is achieved by setting
 * .write_256 = spi_chip_write_1
 */
/* real chunksize is up to 256, logical chunksize is 256 */
int spi_chip_write_256(struct flashctx *flash, uint8_t *buf, unsigned int start,
                       unsigned int len)
{
        return flash->pgm->spi.write_256(flash, buf, start, len);
}

/*
 * Get the lowest allowed address for read accesses. This often happens to
 * be the lowest allowed address for all commands which take an address.
 * This is a programmer limitation.
 */
uint32_t spi_get_valid_read_addr(struct flashctx *flash)
{
        switch (flash->pgm->spi.type) {
#if CONFIG_INTERNAL == 1
#if defined(__i386__) || defined(__x86_64__)
        case SPI_CONTROLLER_ICH7:
                /* Return BBAR for ICH chipsets. */
                return ichspi_bbar;
#endif
#endif
        default:
                return 0;
        }
}

int register_spi_programmer(const struct spi_programmer *pgm)
{
        struct registered_programmer rpgm;

        if (!pgm->write_256 || !pgm->read || !pgm->command ||
            !pgm->multicommand ||
            ((pgm->command == default_spi_send_command) &&
             (pgm->multicommand == default_spi_send_multicommand))) {
                msg_perr("%s called with incomplete programmer definition. "
                         "Please report a bug at flashrom@flashrom.org\n",
                         __func__);
                return ERROR_FLASHROM_BUG;
        }


        rpgm.buses_supported = BUS_SPI;
        rpgm.spi = *pgm;
        return register_programmer(&rpgm);
}