xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision 47b43a1f)
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 
25 #include <libfdt.h>
26 
27 #include "sysemu/device_tree.h"
28 #include "hw/sysbus.h"
29 #include "hw/ppc/spapr.h"
30 #include "hw/ppc/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)
197