gas_mrpc.c

/*
 * Microsemi Switchtec(tm) PCIe Management Library
 * Copyright (c) 2017, Microsemi Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 */
 
#include "switchtec/gas_mrpc.h"
#include "switchtec/switchtec.h"
#include "switchtec_priv.h"
 
#include <string.h>
#include <signal.h>
#include <unistd.h>
 
#define GAS_MRPC_MEMCPY_MAX 512


void gas_mrpc_memcpy_to_gas(struct switchtec_dev *dev, void __gas *dest,
                const void *src, size_t n)
{
    struct gas_mrpc_write cmd;
    int ret;
    uint32_t len;
    uint32_t offset = (uint32_t)(dest - (void __gas *)dev->gas_map);
 
    while (n) {
        len = n;
        if (len > sizeof(cmd.data))
            len = sizeof(cmd.data);
        cmd.len = htole32(len);
        cmd.gas_offset = htole32(offset);
        memcpy(&cmd.data, src, len);
 
        ret = switchtec_cmd(dev, MRPC_GAS_WRITE, &cmd,
                    len + sizeof(cmd) - sizeof(cmd.data),
                    NULL, 0);
        if (ret)
            raise(SIGBUS);
 
        n -= len;
        offset += len;
    }
}

int gas_mrpc_memcpy_from_gas(struct switchtec_dev *dev, void *dest,
                 const void __gas *src, size_t n)
{
    struct gas_mrpc_read cmd;
    int ret;
    uint32_t len;
 
    cmd.gas_offset = htole32((uint32_t)(src - (void __gas *)dev->gas_map));
 
    while (n) {
        len = n;
        if (len > GAS_MRPC_MEMCPY_MAX)
            len = GAS_MRPC_MEMCPY_MAX;
        cmd.len = htole32(len);
 
        ret = switchtec_cmd(dev, MRPC_GAS_READ, &cmd,
                    sizeof(cmd), dest, len);
        if (ret) {
            memset(dest, 0xff, n);
            return ret;
        }
 
        n -= len;
        dest += len;
        cmd.gas_offset += len;
    }
 
    return 0;
}

ssize_t gas_mrpc_write_from_gas(struct switchtec_dev *dev, int fd,
                const void __gas *src, size_t n)
{
    char buf[MRPC_MAX_DATA_LEN];
    ssize_t ret, total = 0;
    size_t txfr_sz;
 
    while (n) {
        txfr_sz = n;
        if (txfr_sz > sizeof(buf))
            txfr_sz = sizeof(buf);
 
        gas_mrpc_memcpy_from_gas(dev, buf, src, txfr_sz);
 
        ret = write(fd, buf, txfr_sz);
        if (ret < 0)
            return ret;
 
        n -= ret;
        src += ret;
        total += ret;
    }
 
    return total;
}