xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision f4152040)
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 <libfdt.h>
30 
31 #include "sysemu/block-backend.h"
32 #include "sysemu/device_tree.h"
33 #include "sysemu/sysemu.h"
34 #include "sysemu/runstate.h"
35 #include "migration/vmstate.h"
36 #include "hw/nvram/chrp_nvram.h"
37 #include "hw/ppc/spapr.h"
38 #include "hw/ppc/spapr_vio.h"
39 #include "hw/qdev-properties.h"
40 #include "hw/qdev-properties-system.h"
41 #include "qom/object.h"
42 
43 struct SpaprNvram {
44     SpaprVioDevice sdev;
45     uint32_t size;
46     uint8_t *buf;
47     BlockBackend *blk;
48     VMChangeStateEntry *vmstate;
49 };
50 
51 #define TYPE_VIO_SPAPR_NVRAM "spapr-nvram"
52 OBJECT_DECLARE_SIMPLE_TYPE(SpaprNvram, VIO_SPAPR_NVRAM)
53 
54 #define MIN_NVRAM_SIZE      (8 * KiB)
55 #define DEFAULT_NVRAM_SIZE  (64 * KiB)
56 #define MAX_NVRAM_SIZE      (1 * MiB)
57 
58 static void rtas_nvram_fetch(PowerPCCPU *cpu, SpaprMachineState *spapr,
59                              uint32_t token, uint32_t nargs,
60                              target_ulong args,
61                              uint32_t nret, target_ulong rets)
62 {
63     SpaprNvram *nvram = spapr->nvram;
64     hwaddr offset, buffer, len;
65     void *membuf;
66 
67     if ((nargs != 3) || (nret != 2)) {
68         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
69         return;
70     }
71 
72     if (!nvram) {
73         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
74         rtas_st(rets, 1, 0);
75         return;
76     }
77 
78     offset = rtas_ld(args, 0);
79     buffer = rtas_ld(args, 1);
80     len = rtas_ld(args, 2);
81 
82     if (((offset + len) < offset)
83         || ((offset + len) > nvram->size)) {
84         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
85         rtas_st(rets, 1, 0);
86         return;
87     }
88 
89     assert(nvram->buf);
90 
91     membuf = cpu_physical_memory_map(buffer, &len, true);
92     memcpy(membuf, nvram->buf + offset, len);
93     cpu_physical_memory_unmap(membuf, len, 1, len);
94 
95     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
96     rtas_st(rets, 1, len);
97 }
98 
99 static void rtas_nvram_store(PowerPCCPU *cpu, SpaprMachineState *spapr,
100                              uint32_t token, uint32_t nargs,
101                              target_ulong args,
102                              uint32_t nret, target_ulong rets)
103 {
104     SpaprNvram *nvram = spapr->nvram;
105     hwaddr offset, buffer, len;
106     int ret;
107     void *membuf;
108 
109     if ((nargs != 3) || (nret != 2)) {
110         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
111         return;
112     }
113 
114     if (!nvram) {
115         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
116         return;
117     }
118 
119     offset = rtas_ld(args, 0);
120     buffer = rtas_ld(args, 1);
121     len = rtas_ld(args, 2);
122 
123     if (((offset + len) < offset)
124         || ((offset + len) > nvram->size)) {
125         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
126         return;
127     }
128 
129     membuf = cpu_physical_memory_map(buffer, &len, false);
130 
131     ret = 0;
132     if (nvram->blk) {
133         ret = blk_pwrite(nvram->blk, offset, len, membuf, 0);
134     }
135 
136     assert(nvram->buf);
137     memcpy(nvram->buf + offset, membuf, len);
138 
139     cpu_physical_memory_unmap(membuf, len, 0, len);
140 
141     rtas_st(rets, 0, (ret < 0) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
142     rtas_st(rets, 1, (ret < 0) ? 0 : len);
143 }
144 
145 static void spapr_nvram_realize(SpaprVioDevice *dev, Error **errp)
146 {
147     SpaprNvram *nvram = VIO_SPAPR_NVRAM(dev);
148     int ret;
149 
150     if (nvram->blk) {
151         int64_t len = blk_getlength(nvram->blk);
152 
153         if (len < 0) {
154             error_setg_errno(errp, -len,
155                              "could not get length of backing image");
156             return;
157         }
158 
159         nvram->size = len;
160 
161         ret = blk_set_perm(nvram->blk,
162                            BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
163                            BLK_PERM_ALL, errp);
164         if (ret < 0) {
165             return;
166         }
167     } else {
168         nvram->size = DEFAULT_NVRAM_SIZE;
169     }
170 
171     nvram->buf = g_malloc0(nvram->size);
172 
173     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
174         error_setg(errp,
175                    "spapr-nvram must be between %" PRId64
176                    " and %" PRId64 " bytes in size",
177                    MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
178         return;
179     }
180 
181     if (nvram->blk) {
182         ret = blk_pread(nvram->blk, 0, nvram->size, nvram->buf, 0);
183 
184         if (ret < 0) {
185             error_setg(errp, "can't read spapr-nvram contents");
186             return;
187         }
188     } else if (nb_prom_envs > 0) {
189         /* Create a system partition to pass the -prom-env variables */
190         chrp_nvram_create_system_partition(nvram->buf, MIN_NVRAM_SIZE / 4,
191                                            nvram->size);
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, bool running, RunState state)
219 {
220     SpaprNvram *nvram = opaque;
221 
222     /* This is called after bdrv_activate_all.  */
223 
224     qemu_del_vm_change_state_handler(nvram->vmstate);
225     nvram->vmstate = NULL;
226 
227     blk_pwrite(nvram->blk, 0, nvram->size, nvram->buf, 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