LXR qemu/hw/nvram/ds1225y.c

   1/*
   2 * QEMU NVRAM emulation for DS1225Y chip
   3 *
   4 * Copyright (c) 2007-2008 Hervé Poussineau
   5 *
   6 * Permission is hereby granted, free of charge, to any person obtaining a copy
   7 * of this software and associated documentation files (the "Software"), to deal
   8 * in the Software without restriction, including without limitation the rights
   9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 * copies of the Software, and to permit persons to whom the Software is
  11 * furnished to do so, subject to the following conditions:
  12 *
  13 * The above copyright notice and this permission notice shall be included in
  14 * all copies or substantial portions of the Software.
  15 *
  16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 * THE SOFTWARE.
  23 */
  24
  25#include "hw/sysbus.h"
  26#include "trace.h"
  27
  28typedef struct {
  29    MemoryRegion iomem;
  30    uint32_t chip_size;
  31    char *filename;
  32    FILE *file;
  33    uint8_t *contents;
  34} NvRamState;
  35
  36static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size)
  37{
  38    NvRamState *s = opaque;
  39    uint32_t val;
  40
  41    val = s->contents[addr];
  42    trace_nvram_read(addr, val);
  43    return val;
  44}
  45
  46static void nvram_write(void *opaque, hwaddr addr, uint64_t val,
  47                        unsigned size)
  48{
  49    NvRamState *s = opaque;
  50
  51    val &= 0xff;
  52    trace_nvram_write(addr, s->contents[addr], val);
  53
  54    s->contents[addr] = val;
  55    if (s->file) {
  56        fseek(s->file, addr, SEEK_SET);
  57        fputc(val, s->file);
  58        fflush(s->file);
  59    }
  60}
  61
  62static const MemoryRegionOps nvram_ops = {
  63    .read = nvram_read,
  64    .write = nvram_write,
  65    .impl = {
  66        .min_access_size = 1,
  67        .max_access_size = 1,
  68    },
  69    .endianness = DEVICE_LITTLE_ENDIAN,
  70};
  71
  72static int nvram_post_load(void *opaque, int version_id)
  73{
  74    NvRamState *s = opaque;
  75
  76    /* Close file, as filename may has changed in load/store process */
  77    if (s->file) {
  78        fclose(s->file);
  79    }
  80
  81    /* Write back nvram contents */
  82    s->file = fopen(s->filename, "wb");
  83    if (s->file) {
  84        /* Write back contents, as 'wb' mode cleaned the file */
  85        if (fwrite(s->contents, s->chip_size, 1, s->file) != 1) {
  86            printf("nvram_post_load: short write\n");
  87        }
  88        fflush(s->file);
  89    }
  90
  91    return 0;
  92}
  93
  94static const VMStateDescription vmstate_nvram = {
  95    .name = "nvram",
  96    .version_id = 0,
  97    .minimum_version_id = 0,
  98    .post_load = nvram_post_load,
  99    .fields = (VMStateField[]) {
 100        VMSTATE_VARRAY_UINT32(contents, NvRamState, chip_size, 0,
 101                              vmstate_info_uint8, uint8_t),
 102        VMSTATE_END_OF_LIST()
 103    }
 104};
 105
 106#define TYPE_DS1225Y "ds1225y"
 107#define DS1225Y(obj) OBJECT_CHECK(SysBusNvRamState, (obj), TYPE_DS1225Y)
 108
 109typedef struct {
 110    SysBusDevice parent_obj;
 111
 112    NvRamState nvram;
 113} SysBusNvRamState;
 114
 115static int nvram_sysbus_initfn(SysBusDevice *dev)
 116{
 117    SysBusNvRamState *sys = DS1225Y(dev);
 118    NvRamState *s = &sys->nvram;
 119    FILE *file;
 120
 121    s->contents = g_malloc0(s->chip_size);
 122
 123    memory_region_init_io(&s->iomem, OBJECT(s), &nvram_ops, s,
 124                          "nvram", s->chip_size);
 125    sysbus_init_mmio(dev, &s->iomem);
 126
 127    /* Read current file */
 128    file = fopen(s->filename, "rb");
 129    if (file) {
 130        /* Read nvram contents */
 131        if (fread(s->contents, s->chip_size, 1, file) != 1) {
 132            printf("nvram_sysbus_initfn: short read\n");
 133        }
 134        fclose(file);
 135    }
 136    nvram_post_load(s, 0);
 137
 138    return 0;
 139}
 140
 141static Property nvram_sysbus_properties[] = {
 142    DEFINE_PROP_UINT32("size", SysBusNvRamState, nvram.chip_size, 0x2000),
 143    DEFINE_PROP_STRING("filename", SysBusNvRamState, nvram.filename),
 144    DEFINE_PROP_END_OF_LIST(),
 145};
 146
 147static void nvram_sysbus_class_init(ObjectClass *klass, void *data)
 148{
 149    DeviceClass *dc = DEVICE_CLASS(klass);
 150    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 151
 152    k->init = nvram_sysbus_initfn;
 153    dc->vmsd = &vmstate_nvram;
 154    dc->props = nvram_sysbus_properties;
 155}
 156
 157static const TypeInfo nvram_sysbus_info = {
 158    .name          = TYPE_DS1225Y,
 159    .parent        = TYPE_SYS_BUS_DEVICE,
 160    .instance_size = sizeof(SysBusNvRamState),
 161    .class_init    = nvram_sysbus_class_init,
 162};
 163
 164static void nvram_register_types(void)
 165{
 166    type_register_static(&nvram_sysbus_info);
 167}
 168
 169type_init(nvram_register_types)
 170