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 29 typedef struct { 30 MemoryRegion iomem; 31 uint32_t chip_size; 32 char *filename; 33 FILE *file; 34 uint8_t *contents; 35 } NvRamState; 36 37 static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size) 38 { 39 NvRamState *s = opaque; 40 uint32_t val; 41 42 val = s->contents[addr]; 43 trace_nvram_read(addr, val); 44 return val; 45 } 46 47 static void nvram_write(void *opaque, hwaddr addr, uint64_t val, 48 unsigned size) 49 { 50 NvRamState *s = opaque; 51 52 val &= 0xff; 53 trace_nvram_write(addr, s->contents[addr], val); 54 55 s->contents[addr] = val; 56 if (s->file) { 57 fseek(s->file, addr, SEEK_SET); 58 fputc(val, s->file); 59 fflush(s->file); 60 } 61 } 62 63 static const MemoryRegionOps nvram_ops = { 64 .read = nvram_read, 65 .write = nvram_write, 66 .impl = { 67 .min_access_size = 1, 68 .max_access_size = 1, 69 }, 70 .endianness = DEVICE_LITTLE_ENDIAN, 71 }; 72 73 static int nvram_post_load(void *opaque, int version_id) 74 { 75 NvRamState *s = opaque; 76 77 /* Close file, as filename may has changed in load/store process */ 78 if (s->file) { 79 fclose(s->file); 80 } 81 82 /* Write back nvram contents */ 83 s->file = fopen(s->filename, "wb"); 84 if (s->file) { 85 /* Write back contents, as 'wb' mode cleaned the file */ 86 if (fwrite(s->contents, s->chip_size, 1, s->file) != 1) { 87 printf("nvram_post_load: short write\n"); 88 } 89 fflush(s->file); 90 } 91 92 return 0; 93 } 94 95 static const VMStateDescription vmstate_nvram = { 96 .name = "nvram", 97 .version_id = 0, 98 .minimum_version_id = 0, 99 .post_load = nvram_post_load, 100 .fields = (VMStateField[]) { 101 VMSTATE_VARRAY_UINT32(contents, NvRamState, chip_size, 0, 102 vmstate_info_uint8, uint8_t), 103 VMSTATE_END_OF_LIST() 104 } 105 }; 106 107 #define TYPE_DS1225Y "ds1225y" 108 #define DS1225Y(obj) OBJECT_CHECK(SysBusNvRamState, (obj), TYPE_DS1225Y) 109 110 typedef struct { 111 SysBusDevice parent_obj; 112 113 NvRamState nvram; 114 } SysBusNvRamState; 115 116 static int nvram_sysbus_initfn(SysBusDevice *dev) 117 { 118 SysBusNvRamState *sys = DS1225Y(dev); 119 NvRamState *s = &sys->nvram; 120 FILE *file; 121 122 s->contents = g_malloc0(s->chip_size); 123 124 memory_region_init_io(&s->iomem, OBJECT(s), &nvram_ops, s, 125 "nvram", s->chip_size); 126 sysbus_init_mmio(dev, &s->iomem); 127 128 /* Read current file */ 129 file = fopen(s->filename, "rb"); 130 if (file) { 131 /* Read nvram contents */ 132 if (fread(s->contents, s->chip_size, 1, file) != 1) { 133 printf("nvram_sysbus_initfn: short read\n"); 134 } 135 fclose(file); 136 } 137 nvram_post_load(s, 0); 138 139 return 0; 140 } 141 142 static Property nvram_sysbus_properties[] = { 143 DEFINE_PROP_UINT32("size", SysBusNvRamState, nvram.chip_size, 0x2000), 144 DEFINE_PROP_STRING("filename", SysBusNvRamState, nvram.filename), 145 DEFINE_PROP_END_OF_LIST(), 146 }; 147 148 static void nvram_sysbus_class_init(ObjectClass *klass, void *data) 149 { 150 DeviceClass *dc = DEVICE_CLASS(klass); 151 SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass); 152 153 k->init = nvram_sysbus_initfn; 154 dc->vmsd = &vmstate_nvram; 155 dc->props = nvram_sysbus_properties; 156 } 157 158 static const TypeInfo nvram_sysbus_info = { 159 .name = TYPE_DS1225Y, 160 .parent = TYPE_SYS_BUS_DEVICE, 161 .instance_size = sizeof(SysBusNvRamState), 162 .class_init = nvram_sysbus_class_init, 163 }; 164 165 static void nvram_register_types(void) 166 { 167 type_register_static(&nvram_sysbus_info); 168 } 169 170 type_init(nvram_register_types) 171