xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision 9c4218e9)
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 "qemu/osdep.h"
26 #include <libfdt.h>
27 
28 #include "sysemu/block-backend.h"
29 #include "sysemu/device_tree.h"
30 #include "hw/sysbus.h"
31 #include "hw/ppc/spapr.h"
32 #include "hw/ppc/spapr_vio.h"
33 
34 typedef struct sPAPRNVRAM {
35     VIOsPAPRDevice sdev;
36     uint32_t size;
37     uint8_t *buf;
38     BlockBackend *blk;
39 } sPAPRNVRAM;
40 
41 #define TYPE_VIO_SPAPR_NVRAM "spapr-nvram"
42 #define VIO_SPAPR_NVRAM(obj) \
43      OBJECT_CHECK(sPAPRNVRAM, (obj), TYPE_VIO_SPAPR_NVRAM)
44 
45 #define MIN_NVRAM_SIZE 8192
46 #define DEFAULT_NVRAM_SIZE 65536
47 #define MAX_NVRAM_SIZE 1048576
48 
49 static void rtas_nvram_fetch(PowerPCCPU *cpu, sPAPRMachineState *spapr,
50                              uint32_t token, uint32_t nargs,
51                              target_ulong args,
52                              uint32_t nret, target_ulong rets)
53 {
54     sPAPRNVRAM *nvram = spapr->nvram;
55     hwaddr offset, buffer, len;
56     void *membuf;
57 
58     if ((nargs != 3) || (nret != 2)) {
59         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
60         return;
61     }
62 
63     if (!nvram) {
64         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
65         rtas_st(rets, 1, 0);
66         return;
67     }
68 
69     offset = rtas_ld(args, 0);
70     buffer = rtas_ld(args, 1);
71     len = rtas_ld(args, 2);
72 
73     if (((offset + len) < offset)
74         || ((offset + len) > nvram->size)) {
75         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
76         rtas_st(rets, 1, 0);
77         return;
78     }
79 
80     assert(nvram->buf);
81 
82     membuf = cpu_physical_memory_map(buffer, &len, 1);
83     memcpy(membuf, nvram->buf + offset, len);
84     cpu_physical_memory_unmap(membuf, len, 1, len);
85 
86     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
87     rtas_st(rets, 1, len);
88 }
89 
90 static void rtas_nvram_store(PowerPCCPU *cpu, sPAPRMachineState *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, RTAS_OUT_PARAM_ERROR);
102         return;
103     }
104 
105     if (!nvram) {
106         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
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, RTAS_OUT_PARAM_ERROR);
117         return;
118     }
119 
120     membuf = cpu_physical_memory_map(buffer, &len, 0);
121 
122     alen = len;
123     if (nvram->blk) {
124         alen = blk_pwrite(nvram->blk, offset, membuf, len);
125     }
126 
127     assert(nvram->buf);
128     memcpy(nvram->buf + offset, membuf, len);
129 
130     cpu_physical_memory_unmap(membuf, len, 0, len);
131 
132     rtas_st(rets, 0, (alen < len) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
133     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
134 }
135 
136 static void spapr_nvram_realize(VIOsPAPRDevice *dev, Error **errp)
137 {
138     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev);
139 
140     if (nvram->blk) {
141         nvram->size = blk_getlength(nvram->blk);
142     } else {
143         nvram->size = DEFAULT_NVRAM_SIZE;
144     }
145 
146     nvram->buf = g_malloc0(nvram->size);
147 
148     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
149         error_setg(errp, "spapr-nvram must be between %d and %d bytes in size",
150                    MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
151         return;
152     }
153 
154     if (nvram->blk) {
155         int alen = blk_pread(nvram->blk, 0, nvram->buf, nvram->size);
156 
157         if (alen != nvram->size) {
158             error_setg(errp, "can't read spapr-nvram contents");
159             return;
160         }
161     }
162 
163     spapr_rtas_register(RTAS_NVRAM_FETCH, "nvram-fetch", rtas_nvram_fetch);
164     spapr_rtas_register(RTAS_NVRAM_STORE, "nvram-store", rtas_nvram_store);
165 }
166 
167 static int spapr_nvram_devnode(VIOsPAPRDevice *dev, void *fdt, int node_off)
168 {
169     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev);
170 
171     return fdt_setprop_cell(fdt, node_off, "#bytes", nvram->size);
172 }
173 
174 static int spapr_nvram_pre_load(void *opaque)
175 {
176     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(opaque);
177 
178     g_free(nvram->buf);
179     nvram->buf = NULL;
180     nvram->size = 0;
181 
182     return 0;
183 }
184 
185 static int spapr_nvram_post_load(void *opaque, int version_id)
186 {
187     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(opaque);
188 
189     if (nvram->blk) {
190         int alen = blk_pwrite(nvram->blk, 0, nvram->buf, nvram->size);
191 
192         if (alen < 0) {
193             return alen;
194         }
195         if (alen != nvram->size) {
196             return -1;
197         }
198     }
199 
200     return 0;
201 }
202 
203 static const VMStateDescription vmstate_spapr_nvram = {
204     .name = "spapr_nvram",
205     .version_id = 1,
206     .minimum_version_id = 1,
207     .pre_load = spapr_nvram_pre_load,
208     .post_load = spapr_nvram_post_load,
209     .fields = (VMStateField[]) {
210         VMSTATE_UINT32(size, sPAPRNVRAM),
211         VMSTATE_VBUFFER_ALLOC_UINT32(buf, sPAPRNVRAM, 1, NULL, 0, size),
212         VMSTATE_END_OF_LIST()
213     },
214 };
215 
216 static Property spapr_nvram_properties[] = {
217     DEFINE_SPAPR_PROPERTIES(sPAPRNVRAM, sdev),
218     DEFINE_PROP_DRIVE("drive", sPAPRNVRAM, blk),
219     DEFINE_PROP_END_OF_LIST(),
220 };
221 
222 static void spapr_nvram_class_init(ObjectClass *klass, void *data)
223 {
224     DeviceClass *dc = DEVICE_CLASS(klass);
225     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
226 
227     k->realize = spapr_nvram_realize;
228     k->devnode = spapr_nvram_devnode;
229     k->dt_name = "nvram";
230     k->dt_type = "nvram";
231     k->dt_compatible = "qemu,spapr-nvram";
232     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
233     dc->props = spapr_nvram_properties;
234     dc->vmsd = &vmstate_spapr_nvram;
235 }
236 
237 static const TypeInfo spapr_nvram_type_info = {
238     .name          = TYPE_VIO_SPAPR_NVRAM,
239     .parent        = TYPE_VIO_SPAPR_DEVICE,
240     .instance_size = sizeof(sPAPRNVRAM),
241     .class_init    = spapr_nvram_class_init,
242 };
243 
244 static void spapr_nvram_register_types(void)
245 {
246     type_register_static(&spapr_nvram_type_info);
247 }
248 
249 type_init(spapr_nvram_register_types)
250