qemu

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/*
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 * Common Hardware Reference Platform NVRAM helper functions.
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 *
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 * The CHRP NVRAM layout is used by OpenBIOS and SLOF. See CHRP
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 * specification, chapter 8, or the LoPAPR specification for details
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 * about the NVRAM layout.
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 *
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 * This code is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published
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 * by the Free Software Foundation; either version 2 of the License,
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 * or (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, see <http://www.gnu.org/licenses/>.
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 */
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#include "qemu/osdep.h"
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#include "qemu/cutils.h"
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#include "qemu/error-report.h"
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#include "hw/nvram/chrp_nvram.h"
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#include "sysemu/sysemu.h"
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static int chrp_nvram_set_var(uint8_t *nvram, int addr, const char *str,
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                              int max_len)
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{
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    int len;
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    len = strlen(str) + 1;
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    if (max_len < len) {
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        return -1;
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    }
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    memcpy(&nvram[addr], str, len);
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    return addr + len;
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}
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/**
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 * Create a "system partition", used for the Open Firmware
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 * environment variables.
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 */
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int chrp_nvram_create_system_partition(uint8_t *data, int min_len, int max_len)
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{
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    ChrpNvramPartHdr *part_header;
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    unsigned int i;
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    int end;
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    if (max_len < sizeof(*part_header)) {
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        goto fail;
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    }
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    part_header = (ChrpNvramPartHdr *)data;
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    part_header->signature = CHRP_NVPART_SYSTEM;
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    pstrcpy(part_header->name, sizeof(part_header->name), "system");
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    end = sizeof(ChrpNvramPartHdr);
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    for (i = 0; i < nb_prom_envs; i++) {
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        end = chrp_nvram_set_var(data, end, prom_envs[i], max_len - end);
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        if (end == -1) {
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            goto fail;
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        }
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    }
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    /* End marker */
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    data[end++] = '\0';
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    end = (end + 15) & ~15;
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    /* XXX: OpenBIOS is not able to grow up a partition. Leave some space for
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       new variables. */
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    if (end < min_len) {
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        end = min_len;
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    }
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    chrp_nvram_finish_partition(part_header, end);
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    return end;
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fail:
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    error_report("NVRAM is too small. Try to pass less data to -prom-env");
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    exit(EXIT_FAILURE);
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}
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/**
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 * Create a "free space" partition
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 */
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int chrp_nvram_create_free_partition(uint8_t *data, int len)
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{
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    ChrpNvramPartHdr *part_header;
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    part_header = (ChrpNvramPartHdr *)data;
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    part_header->signature = CHRP_NVPART_FREE;
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    pstrcpy(part_header->name, sizeof(part_header->name), "free");
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    chrp_nvram_finish_partition(part_header, len);
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    return len;
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}
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