nvsvpd.c

Go to the documentation of this file.

/*
 * Copyright (C) 2010 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * 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; either version 2 of the
 * License, or any later version.
 *
 * 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 Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 * You can also choose to distribute this program under the terms of
 * the Unmodified Binary Distribution Licence (as given in the file
 * COPYING.UBDL), provided that you have satisfied its requirements.
 */

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <ipxe/nvs.h>
#include <ipxe/pci.h>
#include <ipxe/pcivpd.h>
#include <ipxe/nvo.h>
#include <ipxe/nvsvpd.h>

/** @file
 *
 * Non-Volatile Storage using Vital Product Data
 *
 */

/**
 * Read from VPD field
 *
 * @v nvs               NVS device
 * @v field             VPD field descriptor
 * @v data              Data buffer
 * @v len               Length of data buffer
 * @ret rc              Return status code
 */
static int nvs_vpd_read ( struct nvs_device *nvs, unsigned int field,
                          void *data, size_t len ) {
        struct nvs_vpd_device *nvsvpd =
                container_of ( nvs, struct nvs_vpd_device, nvs );
        struct pci_device *pci = nvsvpd->vpd.pci;
        unsigned int address;
        size_t max_len;
        int rc;

        /* Allow reading non-existent field */
        if ( len == 0 )
                return 0;

        /* Locate VPD field */
        if ( ( rc = pci_vpd_find ( &nvsvpd->vpd, field, &address,
                                   &max_len ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS VPD could not locate field "
                       PCI_VPD_FIELD_FMT ": %s\n", PCI_ARGS ( pci ),
                       PCI_VPD_FIELD_ARGS ( field ), strerror ( rc ) );
                return rc;
        }

        /* Sanity check */
        if ( len > max_len ) {
                DBGC ( pci, PCI_FMT " NVS VPD cannot read %#02zx bytes "
                       "beyond field " PCI_VPD_FIELD_FMT " at [%04x,%04zx)\n",
                       PCI_ARGS ( pci ), len, PCI_VPD_FIELD_ARGS ( field ),
                       address, ( address + max_len ) );
                return -ENXIO;
        }

        /* Read from VPD field */
        if ( ( rc = pci_vpd_read ( &nvsvpd->vpd, address, data, len ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS VPD could not read field "
                       PCI_VPD_FIELD_FMT " at [%04x,%04zx): %s\n",
                       PCI_ARGS ( pci ), PCI_VPD_FIELD_ARGS ( field ),
                       address, ( address + len ), strerror ( rc ) );
                return rc;
        }

        return 0;
}

/**
 * Write to VPD field
 *
 * @v nvs               NVS device
 * @v field             VPD field descriptor
 * @v data              Data buffer
 * @v len               Length of data buffer
 * @ret rc              Return status code
 */
static int nvs_vpd_write ( struct nvs_device *nvs, unsigned int field,
                           const void *data, size_t len ) {
        struct nvs_vpd_device *nvsvpd =
                container_of ( nvs, struct nvs_vpd_device, nvs );
        struct pci_device *pci = nvsvpd->vpd.pci;
        unsigned int address;
        size_t max_len;
        int rc;

        /* Locate VPD field */
        if ( ( rc = pci_vpd_find ( &nvsvpd->vpd, field, &address,
                                   &max_len ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS VPD could not locate field "
                       PCI_VPD_FIELD_FMT ": %s\n", PCI_ARGS ( pci ),
                       PCI_VPD_FIELD_ARGS ( field ), strerror ( rc ) );
                return rc;
        }

        /* Sanity check */
        if ( len > max_len ) {
                DBGC ( pci, PCI_FMT " NVS VPD cannot write %#02zx bytes "
                       "beyond field " PCI_VPD_FIELD_FMT " at [%04x,%04zx)\n",
                       PCI_ARGS ( pci ), len, PCI_VPD_FIELD_ARGS ( field ),
                       address, ( address + max_len ) );
                return -ENXIO;
        }

        /* Write field */
        if ( ( rc = pci_vpd_write ( &nvsvpd->vpd, address, data,
                                    len ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS VPD could not write field "
                       PCI_VPD_FIELD_FMT " at [%04x,%04zx): %s\n",
                       PCI_ARGS ( pci ), PCI_VPD_FIELD_ARGS ( field ),
                       address, ( address + len ), strerror ( rc ) );
                return rc;
        }

        return 0;
}

/**
 * Resize VPD field
 *
 * @v nvs               NVS device
 * @v field             VPD field descriptor
 * @v data              Data buffer
 * @v len               Length of data buffer
 * @ret rc              Return status code
 */
static int nvs_vpd_resize ( struct nvs_device *nvs, unsigned int field,
                            size_t len ) {
        struct nvs_vpd_device *nvsvpd =
                container_of ( nvs, struct nvs_vpd_device, nvs );
        struct pci_device *pci = nvsvpd->vpd.pci;
        unsigned int address;
        int rc;

        /* Resize field */
        if ( ( rc = pci_vpd_resize ( &nvsvpd->vpd, field, len,
                                     &address ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS VPD could not resize field "
                       PCI_VPD_FIELD_FMT " to %#02zx bytes: %s\n",
                       PCI_ARGS ( pci ), PCI_VPD_FIELD_ARGS ( field ),
                       len, strerror ( rc ) );
                return rc;
        }

        return 0;
}

/**
 * Initialise NVS VPD device
 *
 * @v nvsvpd            NVS VPD device
 * @v pci               PCI device
 * @ret rc              Return status code
 */
int nvs_vpd_init ( struct nvs_vpd_device *nvsvpd, struct pci_device *pci ) {
        int rc;

        /* Initialise VPD device */
        if ( ( rc = pci_vpd_init ( &nvsvpd->vpd, pci ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS could not initialise "
                       "VPD: %s\n", PCI_ARGS ( pci ), strerror ( rc ) );
                return rc;
        }

        /* Initialise NVS device */
        nvsvpd->nvs.read = nvs_vpd_read;
        nvsvpd->nvs.write = nvs_vpd_write;

        return 0;
}

/**
 * Resize non-volatile option storage within NVS VPD device
 *
 * @v nvo               Non-volatile options block
 * @v len               New length
 * @ret rc              Return status code
 */
static int nvs_vpd_nvo_resize ( struct nvo_block *nvo, size_t len ) {
        int rc;

        /* Resize VPD field */
        if ( ( rc = nvs_vpd_resize ( nvo->nvs, nvo->address, len ) ) != 0 )
                return rc;

        return 0;
}

/**
 * Initialise non-volatile option storage within NVS VPD device
 *
 * @v nvsvpd            NVS VPD device
 * @v field             VPD field descriptor
 * @v nvo               Non-volatile options block
 * @v refcnt            Containing object reference counter, or NULL
 */
void nvs_vpd_nvo_init ( struct nvs_vpd_device *nvsvpd, unsigned int field,
                        struct nvo_block *nvo, struct refcnt *refcnt ) {
        struct pci_device *pci = nvsvpd->vpd.pci;
        unsigned int address;
        size_t len;
        int rc;

        /* Locate VPD field, if present */
        if ( ( rc = pci_vpd_find ( &nvsvpd->vpd, field, &address,
                                   &len ) ) != 0 ) {
                DBGC ( pci, PCI_FMT " NVS VPD field " PCI_VPD_FIELD_FMT
                       " not present; assuming empty\n",
                       PCI_ARGS ( pci ), PCI_VPD_FIELD_ARGS ( field ) );
                len = 0;
        }

        /* Initialise non-volatile options block */
        nvo_init ( nvo, &nvsvpd->nvs, field, len, nvs_vpd_nvo_resize, refcnt );
}