xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision 11938d78)
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 TYPE_VIO_SPAPR_NVRAM "spapr-nvram"
40 #define VIO_SPAPR_NVRAM(obj) \
41      OBJECT_CHECK(sPAPRNVRAM, (obj), TYPE_VIO_SPAPR_NVRAM)
42 
43 #define MIN_NVRAM_SIZE 8192
44 #define DEFAULT_NVRAM_SIZE 65536
45 #define MAX_NVRAM_SIZE (UINT16_MAX * 16)
46 
47 static void rtas_nvram_fetch(PowerPCCPU *cpu, sPAPREnvironment *spapr,
48                              uint32_t token, uint32_t nargs,
49                              target_ulong args,
50                              uint32_t nret, target_ulong rets)
51 {
52     sPAPRNVRAM *nvram = spapr->nvram;
53     hwaddr offset, buffer, len;
54     int alen;
55     void *membuf;
56 
57     if ((nargs != 3) || (nret != 2)) {
58         rtas_st(rets, 0, -3);
59         return;
60     }
61 
62     if (!nvram) {
63         rtas_st(rets, 0, -1);
64         rtas_st(rets, 1, 0);
65         return;
66     }
67 
68     offset = rtas_ld(args, 0);
69     buffer = rtas_ld(args, 1);
70     len = rtas_ld(args, 2);
71 
72     if (((offset + len) < offset)
73         || ((offset + len) > nvram->size)) {
74         rtas_st(rets, 0, -3);
75         rtas_st(rets, 1, 0);
76         return;
77     }
78 
79     membuf = cpu_physical_memory_map(buffer, &len, 1);
80     if (nvram->drive) {
81         alen = bdrv_pread(nvram->drive, offset, membuf, len);
82     } else {
83         assert(nvram->buf);
84 
85         memcpy(membuf, nvram->buf + offset, len);
86         alen = len;
87     }
88     cpu_physical_memory_unmap(membuf, len, 1, len);
89 
90     rtas_st(rets, 0, (alen < len) ? -1 : 0);
91     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
92 }
93 
94 static void rtas_nvram_store(PowerPCCPU *cpu, sPAPREnvironment *spapr,
95                              uint32_t token, uint32_t nargs,
96                              target_ulong args,
97                              uint32_t nret, target_ulong rets)
98 {
99     sPAPRNVRAM *nvram = spapr->nvram;
100     hwaddr offset, buffer, len;
101     int alen;
102     void *membuf;
103 
104     if ((nargs != 3) || (nret != 2)) {
105         rtas_st(rets, 0, -3);
106         return;
107     }
108 
109     if (!nvram) {
110         rtas_st(rets, 0, -1);
111         return;
112     }
113 
114     offset = rtas_ld(args, 0);
115     buffer = rtas_ld(args, 1);
116     len = rtas_ld(args, 2);
117 
118     if (((offset + len) < offset)
119         || ((offset + len) > nvram->size)) {
120         rtas_st(rets, 0, -3);
121         return;
122     }
123 
124     membuf = cpu_physical_memory_map(buffer, &len, 0);
125     if (nvram->drive) {
126         alen = bdrv_pwrite(nvram->drive, offset, membuf, len);
127     } else {
128         assert(nvram->buf);
129 
130         memcpy(nvram->buf + offset, membuf, len);
131         alen = len;
132     }
133     cpu_physical_memory_unmap(membuf, len, 0, len);
134 
135     rtas_st(rets, 0, (alen < len) ? -1 : 0);
136     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
137 }
138 
139 static int spapr_nvram_init(VIOsPAPRDevice *dev)
140 {
141     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev);
142 
143     if (nvram->drive) {
144         nvram->size = bdrv_getlength(nvram->drive);
145     } else {
146         nvram->size = DEFAULT_NVRAM_SIZE;
147         nvram->buf = g_malloc0(nvram->size);
148     }
149 
150     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
151         fprintf(stderr, "spapr-nvram must be between %d and %d bytes in size\n",
152                 MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
153         return -1;
154     }
155 
156     spapr_rtas_register("nvram-fetch", rtas_nvram_fetch);
157     spapr_rtas_register("nvram-store", rtas_nvram_store);
158 
159     return 0;
160 }
161 
162 static int spapr_nvram_devnode(VIOsPAPRDevice *dev, void *fdt, int node_off)
163 {
164     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev);
165 
166     return fdt_setprop_cell(fdt, node_off, "#bytes", nvram->size);
167 }
168 
169 static Property spapr_nvram_properties[] = {
170     DEFINE_SPAPR_PROPERTIES(sPAPRNVRAM, sdev),
171     DEFINE_PROP_DRIVE("drive", sPAPRNVRAM, drive),
172     DEFINE_PROP_END_OF_LIST(),
173 };
174 
175 static void spapr_nvram_class_init(ObjectClass *klass, void *data)
176 {
177     DeviceClass *dc = DEVICE_CLASS(klass);
178     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
179 
180     k->init = spapr_nvram_init;
181     k->devnode = spapr_nvram_devnode;
182     k->dt_name = "nvram";
183     k->dt_type = "nvram";
184     k->dt_compatible = "qemu,spapr-nvram";
185     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
186     dc->props = spapr_nvram_properties;
187 }
188 
189 static const TypeInfo spapr_nvram_type_info = {
190     .name          = TYPE_VIO_SPAPR_NVRAM,
191     .parent        = TYPE_VIO_SPAPR_DEVICE,
192     .instance_size = sizeof(sPAPRNVRAM),
193     .class_init    = spapr_nvram_class_init,
194 };
195 
196 static void spapr_nvram_register_types(void)
197 {
198     type_register_static(&spapr_nvram_type_info);
199 }
200 
201 type_init(spapr_nvram_register_types)
202