xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision f7160f32)
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 "qemu/module.h"
27 #include "qemu/units.h"
28 #include "qapi/error.h"
29 #include "cpu.h"
30 #include <libfdt.h>
31 
32 #include "sysemu/block-backend.h"
33 #include "sysemu/device_tree.h"
34 #include "sysemu/sysemu.h"
35 #include "sysemu/runstate.h"
36 #include "hw/sysbus.h"
37 #include "migration/vmstate.h"
38 #include "hw/nvram/chrp_nvram.h"
39 #include "hw/ppc/spapr.h"
40 #include "hw/ppc/spapr_vio.h"
41 #include "hw/qdev-properties.h"
42 
43 typedef struct SpaprNvram {
44     SpaprVioDevice sdev;
45     uint32_t size;
46     uint8_t *buf;
47     BlockBackend *blk;
48     VMChangeStateEntry *vmstate;
49 } SpaprNvram;
50 
51 #define TYPE_VIO_SPAPR_NVRAM "spapr-nvram"
52 #define VIO_SPAPR_NVRAM(obj) \
53      OBJECT_CHECK(SpaprNvram, (obj), TYPE_VIO_SPAPR_NVRAM)
54 
55 #define MIN_NVRAM_SIZE      (8 * KiB)
56 #define DEFAULT_NVRAM_SIZE  (64 * KiB)
57 #define MAX_NVRAM_SIZE      (1 * MiB)
58 
59 static void rtas_nvram_fetch(PowerPCCPU *cpu, SpaprMachineState *spapr,
60                              uint32_t token, uint32_t nargs,
61                              target_ulong args,
62                              uint32_t nret, target_ulong rets)
63 {
64     SpaprNvram *nvram = spapr->nvram;
65     hwaddr offset, buffer, len;
66     void *membuf;
67 
68     if ((nargs != 3) || (nret != 2)) {
69         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
70         return;
71     }
72 
73     if (!nvram) {
74         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
75         rtas_st(rets, 1, 0);
76         return;
77     }
78 
79     offset = rtas_ld(args, 0);
80     buffer = rtas_ld(args, 1);
81     len = rtas_ld(args, 2);
82 
83     if (((offset + len) < offset)
84         || ((offset + len) > nvram->size)) {
85         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
86         rtas_st(rets, 1, 0);
87         return;
88     }
89 
90     assert(nvram->buf);
91 
92     membuf = cpu_physical_memory_map(buffer, &len, true);
93     memcpy(membuf, nvram->buf + offset, len);
94     cpu_physical_memory_unmap(membuf, len, 1, len);
95 
96     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
97     rtas_st(rets, 1, len);
98 }
99 
100 static void rtas_nvram_store(PowerPCCPU *cpu, SpaprMachineState *spapr,
101                              uint32_t token, uint32_t nargs,
102                              target_ulong args,
103                              uint32_t nret, target_ulong rets)
104 {
105     SpaprNvram *nvram = spapr->nvram;
106     hwaddr offset, buffer, len;
107     int alen;
108     void *membuf;
109 
110     if ((nargs != 3) || (nret != 2)) {
111         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
112         return;
113     }
114 
115     if (!nvram) {
116         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
117         return;
118     }
119 
120     offset = rtas_ld(args, 0);
121     buffer = rtas_ld(args, 1);
122     len = rtas_ld(args, 2);
123 
124     if (((offset + len) < offset)
125         || ((offset + len) > nvram->size)) {
126         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
127         return;
128     }
129 
130     membuf = cpu_physical_memory_map(buffer, &len, false);
131 
132     alen = len;
133     if (nvram->blk) {
134         alen = blk_pwrite(nvram->blk, offset, membuf, len, 0);
135     }
136 
137     assert(nvram->buf);
138     memcpy(nvram->buf + offset, membuf, len);
139 
140     cpu_physical_memory_unmap(membuf, len, 0, len);
141 
142     rtas_st(rets, 0, (alen < len) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
143     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
144 }
145 
146 static void spapr_nvram_realize(SpaprVioDevice *dev, Error **errp)
147 {
148     SpaprNvram *nvram = VIO_SPAPR_NVRAM(dev);
149     int ret;
150 
151     if (nvram->blk) {
152         int64_t len = blk_getlength(nvram->blk);
153 
154         if (len < 0) {
155             error_setg_errno(errp, -len,
156                              "could not get length of backing image");
157             return;
158         }
159 
160         nvram->size = len;
161 
162         ret = blk_set_perm(nvram->blk,
163                            BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
164                            BLK_PERM_ALL, errp);
165         if (ret < 0) {
166             return;
167         }
168     } else {
169         nvram->size = DEFAULT_NVRAM_SIZE;
170     }
171 
172     nvram->buf = g_malloc0(nvram->size);
173 
174     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
175         error_setg(errp,
176                    "spapr-nvram must be between %" PRId64
177                    " and %" PRId64 " bytes in size",
178                    MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
179         return;
180     }
181 
182     if (nvram->blk) {
183         int alen = blk_pread(nvram->blk, 0, nvram->buf, nvram->size);
184 
185         if (alen != nvram->size) {
186             error_setg(errp, "can't read spapr-nvram contents");
187             return;
188         }
189     } else if (nb_prom_envs > 0) {
190         /* Create a system partition to pass the -prom-env variables */
191         chrp_nvram_create_system_partition(nvram->buf, MIN_NVRAM_SIZE / 4);
192         chrp_nvram_create_free_partition(&nvram->buf[MIN_NVRAM_SIZE / 4],
193                                          nvram->size - MIN_NVRAM_SIZE / 4);
194     }
195 
196     spapr_rtas_register(RTAS_NVRAM_FETCH, "nvram-fetch", rtas_nvram_fetch);
197     spapr_rtas_register(RTAS_NVRAM_STORE, "nvram-store", rtas_nvram_store);
198 }
199 
200 static int spapr_nvram_devnode(SpaprVioDevice *dev, void *fdt, int node_off)
201 {
202     SpaprNvram *nvram = VIO_SPAPR_NVRAM(dev);
203 
204     return fdt_setprop_cell(fdt, node_off, "#bytes", nvram->size);
205 }
206 
207 static int spapr_nvram_pre_load(void *opaque)
208 {
209     SpaprNvram *nvram = VIO_SPAPR_NVRAM(opaque);
210 
211     g_free(nvram->buf);
212     nvram->buf = NULL;
213     nvram->size = 0;
214 
215     return 0;
216 }
217 
218 static void postload_update_cb(void *opaque, int running, RunState state)
219 {
220     SpaprNvram *nvram = opaque;
221 
222     /* This is called after bdrv_invalidate_cache_all.  */
223 
224     qemu_del_vm_change_state_handler(nvram->vmstate);
225     nvram->vmstate = NULL;
226 
227     blk_pwrite(nvram->blk, 0, nvram->buf, nvram->size, 0);
228 }
229 
230 static int spapr_nvram_post_load(void *opaque, int version_id)
231 {
232     SpaprNvram *nvram = VIO_SPAPR_NVRAM(opaque);
233 
234     if (nvram->blk) {
235         nvram->vmstate = qemu_add_vm_change_state_handler(postload_update_cb,
236                                                           nvram);
237     }
238 
239     return 0;
240 }
241 
242 static const VMStateDescription vmstate_spapr_nvram = {
243     .name = "spapr_nvram",
244     .version_id = 1,
245     .minimum_version_id = 1,
246     .pre_load = spapr_nvram_pre_load,
247     .post_load = spapr_nvram_post_load,
248     .fields = (VMStateField[]) {
249         VMSTATE_UINT32(size, SpaprNvram),
250         VMSTATE_VBUFFER_ALLOC_UINT32(buf, SpaprNvram, 1, NULL, size),
251         VMSTATE_END_OF_LIST()
252     },
253 };
254 
255 static Property spapr_nvram_properties[] = {
256     DEFINE_SPAPR_PROPERTIES(SpaprNvram, sdev),
257     DEFINE_PROP_DRIVE("drive", SpaprNvram, blk),
258     DEFINE_PROP_END_OF_LIST(),
259 };
260 
261 static void spapr_nvram_class_init(ObjectClass *klass, void *data)
262 {
263     DeviceClass *dc = DEVICE_CLASS(klass);
264     SpaprVioDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
265 
266     k->realize = spapr_nvram_realize;
267     k->devnode = spapr_nvram_devnode;
268     k->dt_name = "nvram";
269     k->dt_type = "nvram";
270     k->dt_compatible = "qemu,spapr-nvram";
271     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
272     device_class_set_props(dc, spapr_nvram_properties);
273     dc->vmsd = &vmstate_spapr_nvram;
274     /* Reason: Internal device only, uses spapr_rtas_register() in realize() */
275     dc->user_creatable = false;
276 }
277 
278 static const TypeInfo spapr_nvram_type_info = {
279     .name          = TYPE_VIO_SPAPR_NVRAM,
280     .parent        = TYPE_VIO_SPAPR_DEVICE,
281     .instance_size = sizeof(SpaprNvram),
282     .class_init    = spapr_nvram_class_init,
283 };
284 
285 static void spapr_nvram_register_types(void)
286 {
287     type_register_static(&spapr_nvram_type_info);
288 }
289 
290 type_init(spapr_nvram_register_types)
291