hw/spapr_nvram.c

   1 /*
   2  * QEMU sPAPR NVRAM emulation
   3  *
   4  * Copyright (C) 2012 David Gibson, IBM Corporation.
   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 #include <sys/mman.h>
  25 #include <libfdt.h>
  26
  27 #include "device_tree.h"
  28 #include "hw/sysbus.h"
  29 #include "hw/spapr.h"
  30 #include "hw/spapr_vio.h"
  31
  32 typedef struct sPAPRNVRAM {
  33     VIOsPAPRDevice sdev;
  34     uint32_t size;
  35     uint8_t *buf;
  36     BlockDriverState *drive;
  37 } sPAPRNVRAM;
  38
  39 #define MIN_NVRAM_SIZE 8192
  40 #define DEFAULT_NVRAM_SIZE 65536
  41 #define MAX_NVRAM_SIZE (UINT16_MAX * 16)
  42
  43 static void rtas_nvram_fetch(sPAPREnvironment *spapr,
  44                              uint32_t token, uint32_t nargs,
  45                              target_ulong args,
  46                              uint32_t nret, target_ulong rets)
  47 {
  48     sPAPRNVRAM *nvram = spapr->nvram;
  49     hwaddr offset, buffer, len;
  50     int alen;
  51     void *membuf;
  52
  53     if ((nargs != 3) || (nret != 2)) {
  54         rtas_st(rets, 0, -3);
  55         return;
  56     }
  57
  58     if (!nvram) {
  59         rtas_st(rets, 0, -1);
  60         rtas_st(rets, 1, 0);
  61         return;
  62     }
  63
  64     offset = rtas_ld(args, 0);
  65     buffer = rtas_ld(args, 1);
  66     len = rtas_ld(args, 2);
  67
  68     if (((offset + len) < offset)
  69         || ((offset + len) > nvram->size)) {
  70         rtas_st(rets, 0, -3);
  71         rtas_st(rets, 1, 0);
  72         return;
  73     }
  74
  75     membuf = cpu_physical_memory_map(buffer, &len, 1);
  76     if (nvram->drive) {
  77         alen = bdrv_pread(nvram->drive, offset, membuf, len);
  78     } else {
  79         assert(nvram->buf);
  80
  81         memcpy(membuf, nvram->buf + offset, len);
  82         alen = len;
  83     }
  84     cpu_physical_memory_unmap(membuf, len, 1, len);
  85
  86     rtas_st(rets, 0, (alen < len) ? -1 : 0);
  87     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
  88 }
  89
  90 static void rtas_nvram_store(sPAPREnvironment *spapr,
  91                              uint32_t token, uint32_t nargs,
  92                              target_ulong args,
  93                              uint32_t nret, target_ulong rets)
  94 {
  95     sPAPRNVRAM *nvram = spapr->nvram;
  96     hwaddr offset, buffer, len;
  97     int alen;
  98     void *membuf;
  99
 100     if ((nargs != 3) || (nret != 2)) {
 101         rtas_st(rets, 0, -3);
 102         return;
 103     }
 104
 105     if (!nvram) {
 106         rtas_st(rets, 0, -1);
 107         return;
 108     }
 109
 110     offset = rtas_ld(args, 0);
 111     buffer = rtas_ld(args, 1);
 112     len = rtas_ld(args, 2);
 113
 114     if (((offset + len) < offset)
 115         || ((offset + len) > nvram->size)) {
 116         rtas_st(rets, 0, -3);
 117         return;
 118     }
 119
 120     membuf = cpu_physical_memory_map(buffer, &len, 0);
 121     if (nvram->drive) {
 122         alen = bdrv_pwrite(nvram->drive, offset, membuf, len);
 123     } else {
 124         assert(nvram->buf);
 125
 126         memcpy(nvram->buf + offset, membuf, len);
 127         alen = len;
 128     }
 129     cpu_physical_memory_unmap(membuf, len, 0, len);
 130
 131     rtas_st(rets, 0, (alen < len) ? -1 : 0);
 132     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
 133 }
 134
 135 static int spapr_nvram_init(VIOsPAPRDevice *dev)
 136 {
 137     sPAPRNVRAM *nvram = (sPAPRNVRAM *)dev;
 138
 139     if (nvram->drive) {
 140         nvram->size = bdrv_getlength(nvram->drive);
 141     } else {
 142         nvram->size = DEFAULT_NVRAM_SIZE;
 143         nvram->buf = g_malloc0(nvram->size);
 144     }
 145
 146     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
 147         fprintf(stderr, "spapr-nvram must be between %d and %d bytes in size\n",
 148                 MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
 149         return -1;
 150     }
 151
 152     spapr_rtas_register("nvram-fetch", rtas_nvram_fetch);
 153     spapr_rtas_register("nvram-store", rtas_nvram_store);
 154
 155     return 0;
 156 }
 157
 158 static int spapr_nvram_devnode(VIOsPAPRDevice *dev, void *fdt, int node_off)
 159 {
 160     sPAPRNVRAM *nvram = (sPAPRNVRAM *)dev;
 161
 162     return fdt_setprop_cell(fdt, node_off, "#bytes", nvram->size);
 163 }
 164
 165 static Property spapr_nvram_properties[] = {
 166     DEFINE_SPAPR_PROPERTIES(sPAPRNVRAM, sdev),
 167     DEFINE_PROP_DRIVE("drive", sPAPRNVRAM, drive),
 168     DEFINE_PROP_END_OF_LIST(),
 169 };
 170
 171 static void spapr_nvram_class_init(ObjectClass *klass, void *data)
 172 {
 173     DeviceClass *dc = DEVICE_CLASS(klass);
 174     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
 175
 176     k->init = spapr_nvram_init;
 177     k->devnode = spapr_nvram_devnode;
 178     k->dt_name = "nvram";
 179     k->dt_type = "nvram";
 180     k->dt_compatible = "qemu,spapr-nvram";
 181     dc->props = spapr_nvram_properties;
 182 }
 183
 184 static const TypeInfo spapr_nvram_type_info = {
 185     .name          = "spapr-nvram",
 186     .parent        = TYPE_VIO_SPAPR_DEVICE,
 187     .instance_size = sizeof(sPAPRNVRAM),
 188     .class_init    = spapr_nvram_class_init,
 189 };
 190
 191 static void spapr_nvram_register_types(void)
 192 {
 193     type_register_static(&spapr_nvram_type_info);
 194 }
 195
 196 type_init(spapr_nvram_register_types)