qemu

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/*
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 * QEMU NVRAM emulation for DS1225Y chip
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 *
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 * Copyright (c) 2007-2008 Hervé Poussineau
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 *
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 * Permission is hereby granted, free of charge, to any person obtaining a copy
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 * of this software and associated documentation files (the "Software"), to deal
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 * in the Software without restriction, including without limitation the rights
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 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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 * copies of the Software, and to permit persons to whom the Software is
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 * furnished to do so, subject to the following conditions:
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 *
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 * The above copyright notice and this permission notice shall be included in
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 * all copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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 * THE SOFTWARE.
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 */
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#include "qemu/osdep.h"
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#include "hw/qdev-properties.h"
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#include "hw/sysbus.h"
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#include "migration/vmstate.h"
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#include "trace.h"
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#include "qemu/error-report.h"
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#include "qemu/module.h"
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#include "qom/object.h"
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typedef struct {
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    MemoryRegion iomem;
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    uint32_t chip_size;
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    char *filename;
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    FILE *file;
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    uint8_t *contents;
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} NvRamState;
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static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size)
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{
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    NvRamState *s = opaque;
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    uint32_t val;
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    val = s->contents[addr];
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    trace_nvram_read(addr, val);
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    return val;
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}
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static void nvram_write(void *opaque, hwaddr addr, uint64_t val,
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                        unsigned size)
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{
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    NvRamState *s = opaque;
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    val &= 0xff;
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    trace_nvram_write(addr, s->contents[addr], val);
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    s->contents[addr] = val;
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    if (s->file) {
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        fseek(s->file, addr, SEEK_SET);
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        fputc(val, s->file);
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        fflush(s->file);
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    }
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}
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static const MemoryRegionOps nvram_ops = {
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    .read = nvram_read,
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    .write = nvram_write,
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    .impl = {
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        .min_access_size = 1,
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        .max_access_size = 1,
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    },
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    .endianness = DEVICE_LITTLE_ENDIAN,
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};
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static int nvram_post_load(void *opaque, int version_id)
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{
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    NvRamState *s = opaque;
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    /* Close file, as filename may has changed in load/store process */
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    if (s->file) {
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        fclose(s->file);
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    }
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    /* Write back nvram contents */
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    s->file = s->filename ? fopen(s->filename, "wb") : NULL;
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    if (s->file) {
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        /* Write back contents, as 'wb' mode cleaned the file */
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        if (fwrite(s->contents, s->chip_size, 1, s->file) != 1) {
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            printf("nvram_post_load: short write\n");
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        }
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        fflush(s->file);
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    }
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    return 0;
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}
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static const VMStateDescription vmstate_nvram = {
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    .name = "nvram",
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    .version_id = 0,
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    .minimum_version_id = 0,
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    .post_load = nvram_post_load,
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    .fields = (const VMStateField[]) {
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        VMSTATE_VARRAY_UINT32(contents, NvRamState, chip_size, 0,
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                              vmstate_info_uint8, uint8_t),
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        VMSTATE_END_OF_LIST()
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    }
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};
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#define TYPE_DS1225Y "ds1225y"
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OBJECT_DECLARE_SIMPLE_TYPE(SysBusNvRamState, DS1225Y)
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struct SysBusNvRamState {
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    SysBusDevice parent_obj;
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    NvRamState nvram;
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};
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static void nvram_sysbus_realize(DeviceState *dev, Error **errp)
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{
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    SysBusNvRamState *sys = DS1225Y(dev);
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    NvRamState *s = &sys->nvram;
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    FILE *file;
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    s->contents = g_malloc0(s->chip_size);
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    memory_region_init_io(&s->iomem, OBJECT(s), &nvram_ops, s,
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                          "nvram", s->chip_size);
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    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
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    /* Read current file */
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    file = s->filename ? fopen(s->filename, "rb") : NULL;
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    if (file) {
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        /* Read nvram contents */
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        if (fread(s->contents, s->chip_size, 1, file) != 1) {
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            error_report("nvram_sysbus_realize: short read");
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        }
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        fclose(file);
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    }
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    nvram_post_load(s, 0);
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}
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static Property nvram_sysbus_properties[] = {
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    DEFINE_PROP_UINT32("size", SysBusNvRamState, nvram.chip_size, 0x2000),
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    DEFINE_PROP_STRING("filename", SysBusNvRamState, nvram.filename),
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    DEFINE_PROP_END_OF_LIST(),
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};
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static void nvram_sysbus_class_init(ObjectClass *klass, void *data)
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{
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    DeviceClass *dc = DEVICE_CLASS(klass);
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    dc->realize = nvram_sysbus_realize;
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    dc->vmsd = &vmstate_nvram;
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    device_class_set_props(dc, nvram_sysbus_properties);
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}
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static const TypeInfo nvram_sysbus_info = {
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    .name          = TYPE_DS1225Y,
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    .parent        = TYPE_SYS_BUS_DEVICE,
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    .instance_size = sizeof(SysBusNvRamState),
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    .class_init    = nvram_sysbus_class_init,
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};
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static void nvram_register_types(void)
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{
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    type_register_static(&nvram_sysbus_info);
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}
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type_init(nvram_register_types)
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