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 "qemu/osdep.h" 26 #include "hw/sysbus.h" 27 #include "trace.h" 28 #include "qemu/error-report.h" 29 30 typedef struct { 31 MemoryRegion iomem; 32 uint32_t chip_size; 33 char *filename; 34 FILE *file; 35 uint8_t *contents; 36 } NvRamState; 37 38 static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size) 39 { 40 NvRamState *s = opaque; 41 uint32_t val; 42 43 val = s->contents[addr]; 44 trace_nvram_read(addr, val); 45 return val; 46 } 47 48 static void nvram_write(void *opaque, hwaddr addr, uint64_t val, 49 unsigned size) 50 { 51 NvRamState *s = opaque; 52 53 val &= 0xff; 54 trace_nvram_write(addr, s->contents[addr], val); 55 56 s->contents[addr] = val; 57 if (s->file) { 58 fseek(s->file, addr, SEEK_SET); 59 fputc(val, s->file); 60 fflush(s->file); 61 } 62 } 63 64 static const MemoryRegionOps nvram_ops = { 65 .read = nvram_read, 66 .write = nvram_write, 67 .impl = { 68 .min_access_size = 1, 69 .max_access_size = 1, 70 }, 71 .endianness = DEVICE_LITTLE_ENDIAN, 72 }; 73 74 static int nvram_post_load(void *opaque, int version_id) 75 { 76 NvRamState *s = opaque; 77 78 /* Close file, as filename may has changed in load/store process */ 79 if (s->file) { 80 fclose(s->file); 81 } 82 83 /* Write back nvram contents */ 84 s->file = s->filename ? fopen(s->filename, "wb") : NULL; 85 if (s->file) { 86 /* Write back contents, as 'wb' mode cleaned the file */ 87 if (fwrite(s->contents, s->chip_size, 1, s->file) != 1) { 88 printf("nvram_post_load: short write\n"); 89 } 90 fflush(s->file); 91 } 92 93 return 0; 94 } 95 96 static const VMStateDescription vmstate_nvram = { 97 .name = "nvram", 98 .version_id = 0, 99 .minimum_version_id = 0, 100 .post_load = nvram_post_load, 101 .fields = (VMStateField[]) { 102 VMSTATE_VARRAY_UINT32(contents, NvRamState, chip_size, 0, 103 vmstate_info_uint8, uint8_t), 104 VMSTATE_END_OF_LIST() 105 } 106 }; 107 108 #define TYPE_DS1225Y "ds1225y" 109 #define DS1225Y(obj) OBJECT_CHECK(SysBusNvRamState, (obj), TYPE_DS1225Y) 110 111 typedef struct { 112 SysBusDevice parent_obj; 113 114 NvRamState nvram; 115 } SysBusNvRamState; 116 117 static void nvram_sysbus_realize(DeviceState *dev, Error **errp) 118 { 119 SysBusNvRamState *sys = DS1225Y(dev); 120 NvRamState *s = &sys->nvram; 121 FILE *file; 122 123 s->contents = g_malloc0(s->chip_size); 124 125 memory_region_init_io(&s->iomem, OBJECT(s), &nvram_ops, s, 126 "nvram", s->chip_size); 127 sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem); 128 129 /* Read current file */ 130 file = s->filename ? fopen(s->filename, "rb") : NULL; 131 if (file) { 132 /* Read nvram contents */ 133 if (fread(s->contents, s->chip_size, 1, file) != 1) { 134 error_report("nvram_sysbus_realize: short read"); 135 } 136 fclose(file); 137 } 138 nvram_post_load(s, 0); 139 } 140 141 static 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 }; 146 147 static void nvram_sysbus_class_init(ObjectClass *klass, void *data) 148 { 149 DeviceClass *dc = DEVICE_CLASS(klass); 150 151 dc->realize = nvram_sysbus_realize; 152 dc->vmsd = &vmstate_nvram; 153 dc->props = nvram_sysbus_properties; 154 } 155 156 static const TypeInfo nvram_sysbus_info = { 157 .name = TYPE_DS1225Y, 158 .parent = TYPE_SYS_BUS_DEVICE, 159 .instance_size = sizeof(SysBusNvRamState), 160 .class_init = nvram_sysbus_class_init, 161 }; 162 163 static void nvram_register_types(void) 164 { 165 type_register_static(&nvram_sysbus_info); 166 } 167 168 type_init(nvram_register_types) 169