xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision 6e99f574)
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 "qapi/error.h"
27 #include "qemu-common.h"
28 #include "cpu.h"
29 #include <libfdt.h>
30 
31 #include "sysemu/block-backend.h"
32 #include "sysemu/device_tree.h"
33 #include "hw/sysbus.h"
34 #include "hw/ppc/spapr.h"
35 #include "hw/ppc/spapr_vio.h"
36 
37 typedef struct sPAPRNVRAM {
38     VIOsPAPRDevice sdev;
39     uint32_t size;
40     uint8_t *buf;
41     BlockBackend *blk;
42     VMChangeStateEntry *vmstate;
43 } sPAPRNVRAM;
44 
45 #define TYPE_VIO_SPAPR_NVRAM "spapr-nvram"
46 #define VIO_SPAPR_NVRAM(obj) \
47      OBJECT_CHECK(sPAPRNVRAM, (obj), TYPE_VIO_SPAPR_NVRAM)
48 
49 #define MIN_NVRAM_SIZE 8192
50 #define DEFAULT_NVRAM_SIZE 65536
51 #define MAX_NVRAM_SIZE 1048576
52 
53 static void rtas_nvram_fetch(PowerPCCPU *cpu, sPAPRMachineState *spapr,
54                              uint32_t token, uint32_t nargs,
55                              target_ulong args,
56                              uint32_t nret, target_ulong rets)
57 {
58     sPAPRNVRAM *nvram = spapr->nvram;
59     hwaddr offset, buffer, len;
60     void *membuf;
61 
62     if ((nargs != 3) || (nret != 2)) {
63         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
64         return;
65     }
66 
67     if (!nvram) {
68         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
69         rtas_st(rets, 1, 0);
70         return;
71     }
72 
73     offset = rtas_ld(args, 0);
74     buffer = rtas_ld(args, 1);
75     len = rtas_ld(args, 2);
76 
77     if (((offset + len) < offset)
78         || ((offset + len) > nvram->size)) {
79         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
80         rtas_st(rets, 1, 0);
81         return;
82     }
83 
84     assert(nvram->buf);
85 
86     membuf = cpu_physical_memory_map(buffer, &len, 1);
87     memcpy(membuf, nvram->buf + offset, len);
88     cpu_physical_memory_unmap(membuf, len, 1, len);
89 
90     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
91     rtas_st(rets, 1, len);
92 }
93 
94 static void rtas_nvram_store(PowerPCCPU *cpu, sPAPRMachineState *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, RTAS_OUT_PARAM_ERROR);
106         return;
107     }
108 
109     if (!nvram) {
110         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
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, RTAS_OUT_PARAM_ERROR);
121         return;
122     }
123 
124     membuf = cpu_physical_memory_map(buffer, &len, 0);
125 
126     alen = len;
127     if (nvram->blk) {
128         alen = blk_pwrite(nvram->blk, offset, membuf, len, 0);
129     }
130 
131     assert(nvram->buf);
132     memcpy(nvram->buf + offset, membuf, len);
133 
134     cpu_physical_memory_unmap(membuf, len, 0, len);
135 
136     rtas_st(rets, 0, (alen < len) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
137     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
138 }
139 
140 static void spapr_nvram_realize(VIOsPAPRDevice *dev, Error **errp)
141 {
142     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev);
143 
144     if (nvram->blk) {
145         nvram->size = blk_getlength(nvram->blk);
146     } else {
147         nvram->size = DEFAULT_NVRAM_SIZE;
148     }
149 
150     nvram->buf = g_malloc0(nvram->size);
151 
152     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
153         error_setg(errp, "spapr-nvram must be between %d and %d bytes in size",
154                    MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
155         return;
156     }
157 
158     if (nvram->blk) {
159         int alen = blk_pread(nvram->blk, 0, nvram->buf, nvram->size);
160 
161         if (alen != nvram->size) {
162             error_setg(errp, "can't read spapr-nvram contents");
163             return;
164         }
165     }
166 
167     spapr_rtas_register(RTAS_NVRAM_FETCH, "nvram-fetch", rtas_nvram_fetch);
168     spapr_rtas_register(RTAS_NVRAM_STORE, "nvram-store", rtas_nvram_store);
169 }
170 
171 static int spapr_nvram_devnode(VIOsPAPRDevice *dev, void *fdt, int node_off)
172 {
173     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev);
174 
175     return fdt_setprop_cell(fdt, node_off, "#bytes", nvram->size);
176 }
177 
178 static int spapr_nvram_pre_load(void *opaque)
179 {
180     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(opaque);
181 
182     g_free(nvram->buf);
183     nvram->buf = NULL;
184     nvram->size = 0;
185 
186     return 0;
187 }
188 
189 static void postload_update_cb(void *opaque, int running, RunState state)
190 {
191     sPAPRNVRAM *nvram = opaque;
192 
193     /* This is called after bdrv_invalidate_cache_all.  */
194 
195     qemu_del_vm_change_state_handler(nvram->vmstate);
196     nvram->vmstate = NULL;
197 
198     blk_pwrite(nvram->blk, 0, nvram->buf, nvram->size, 0);
199 }
200 
201 static int spapr_nvram_post_load(void *opaque, int version_id)
202 {
203     sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(opaque);
204 
205     if (nvram->blk) {
206         nvram->vmstate = qemu_add_vm_change_state_handler(postload_update_cb,
207                                                           nvram);
208     }
209 
210     return 0;
211 }
212 
213 static const VMStateDescription vmstate_spapr_nvram = {
214     .name = "spapr_nvram",
215     .version_id = 1,
216     .minimum_version_id = 1,
217     .pre_load = spapr_nvram_pre_load,
218     .post_load = spapr_nvram_post_load,
219     .fields = (VMStateField[]) {
220         VMSTATE_UINT32(size, sPAPRNVRAM),
221         VMSTATE_VBUFFER_ALLOC_UINT32(buf, sPAPRNVRAM, 1, NULL, 0, size),
222         VMSTATE_END_OF_LIST()
223     },
224 };
225 
226 static Property spapr_nvram_properties[] = {
227     DEFINE_SPAPR_PROPERTIES(sPAPRNVRAM, sdev),
228     DEFINE_PROP_DRIVE("drive", sPAPRNVRAM, blk),
229     DEFINE_PROP_END_OF_LIST(),
230 };
231 
232 static void spapr_nvram_class_init(ObjectClass *klass, void *data)
233 {
234     DeviceClass *dc = DEVICE_CLASS(klass);
235     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
236 
237     k->realize = spapr_nvram_realize;
238     k->devnode = spapr_nvram_devnode;
239     k->dt_name = "nvram";
240     k->dt_type = "nvram";
241     k->dt_compatible = "qemu,spapr-nvram";
242     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
243     dc->props = spapr_nvram_properties;
244     dc->vmsd = &vmstate_spapr_nvram;
245 }
246 
247 static const TypeInfo spapr_nvram_type_info = {
248     .name          = TYPE_VIO_SPAPR_NVRAM,
249     .parent        = TYPE_VIO_SPAPR_DEVICE,
250     .instance_size = sizeof(sPAPRNVRAM),
251     .class_init    = spapr_nvram_class_init,
252 };
253 
254 static void spapr_nvram_register_types(void)
255 {
256     type_register_static(&spapr_nvram_type_info);
257 }
258 
259 type_init(spapr_nvram_register_types)
260