xref: /openbmc/qemu/hw/nvram/spapr_nvram.c (revision 8cf108c5)
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/units.h"
27 #include "qapi/error.h"
28 #include "qemu-common.h"
29 #include "cpu.h"
30 #include <libfdt.h>
31 
32 #include "sysemu/block-backend.h"
33 #include "sysemu/device_tree.h"
34 #include "hw/sysbus.h"
35 #include "hw/nvram/chrp_nvram.h"
36 #include "hw/ppc/spapr.h"
37 #include "hw/ppc/spapr_vio.h"
38 
39 typedef struct SpaprNvram {
40     SpaprVioDevice sdev;
41     uint32_t size;
42     uint8_t *buf;
43     BlockBackend *blk;
44     VMChangeStateEntry *vmstate;
45 } SpaprNvram;
46 
47 #define TYPE_VIO_SPAPR_NVRAM "spapr-nvram"
48 #define VIO_SPAPR_NVRAM(obj) \
49      OBJECT_CHECK(SpaprNvram, (obj), TYPE_VIO_SPAPR_NVRAM)
50 
51 #define MIN_NVRAM_SIZE      (8 * KiB)
52 #define DEFAULT_NVRAM_SIZE  (64 * KiB)
53 #define MAX_NVRAM_SIZE      (1 * MiB)
54 
55 static void rtas_nvram_fetch(PowerPCCPU *cpu, SpaprMachineState *spapr,
56                              uint32_t token, uint32_t nargs,
57                              target_ulong args,
58                              uint32_t nret, target_ulong rets)
59 {
60     SpaprNvram *nvram = spapr->nvram;
61     hwaddr offset, buffer, len;
62     void *membuf;
63 
64     if ((nargs != 3) || (nret != 2)) {
65         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
66         return;
67     }
68 
69     if (!nvram) {
70         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
71         rtas_st(rets, 1, 0);
72         return;
73     }
74 
75     offset = rtas_ld(args, 0);
76     buffer = rtas_ld(args, 1);
77     len = rtas_ld(args, 2);
78 
79     if (((offset + len) < offset)
80         || ((offset + len) > nvram->size)) {
81         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
82         rtas_st(rets, 1, 0);
83         return;
84     }
85 
86     assert(nvram->buf);
87 
88     membuf = cpu_physical_memory_map(buffer, &len, 1);
89     memcpy(membuf, nvram->buf + offset, len);
90     cpu_physical_memory_unmap(membuf, len, 1, len);
91 
92     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
93     rtas_st(rets, 1, len);
94 }
95 
96 static void rtas_nvram_store(PowerPCCPU *cpu, SpaprMachineState *spapr,
97                              uint32_t token, uint32_t nargs,
98                              target_ulong args,
99                              uint32_t nret, target_ulong rets)
100 {
101     SpaprNvram *nvram = spapr->nvram;
102     hwaddr offset, buffer, len;
103     int alen;
104     void *membuf;
105 
106     if ((nargs != 3) || (nret != 2)) {
107         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
108         return;
109     }
110 
111     if (!nvram) {
112         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
113         return;
114     }
115 
116     offset = rtas_ld(args, 0);
117     buffer = rtas_ld(args, 1);
118     len = rtas_ld(args, 2);
119 
120     if (((offset + len) < offset)
121         || ((offset + len) > nvram->size)) {
122         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
123         return;
124     }
125 
126     membuf = cpu_physical_memory_map(buffer, &len, 0);
127 
128     alen = len;
129     if (nvram->blk) {
130         alen = blk_pwrite(nvram->blk, offset, membuf, len, 0);
131     }
132 
133     assert(nvram->buf);
134     memcpy(nvram->buf + offset, membuf, len);
135 
136     cpu_physical_memory_unmap(membuf, len, 0, len);
137 
138     rtas_st(rets, 0, (alen < len) ? RTAS_OUT_HW_ERROR : RTAS_OUT_SUCCESS);
139     rtas_st(rets, 1, (alen < 0) ? 0 : alen);
140 }
141 
142 static void spapr_nvram_realize(SpaprVioDevice *dev, Error **errp)
143 {
144     SpaprNvram *nvram = VIO_SPAPR_NVRAM(dev);
145     int ret;
146 
147     if (nvram->blk) {
148         int64_t len = blk_getlength(nvram->blk);
149 
150         if (len < 0) {
151             error_setg_errno(errp, -len,
152                              "could not get length of backing image");
153             return;
154         }
155 
156         nvram->size = len;
157 
158         ret = blk_set_perm(nvram->blk,
159                            BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
160                            BLK_PERM_ALL, errp);
161         if (ret < 0) {
162             return;
163         }
164     } else {
165         nvram->size = DEFAULT_NVRAM_SIZE;
166     }
167 
168     nvram->buf = g_malloc0(nvram->size);
169 
170     if ((nvram->size < MIN_NVRAM_SIZE) || (nvram->size > MAX_NVRAM_SIZE)) {
171         error_setg(errp,
172                    "spapr-nvram must be between %" PRId64
173                    " and %" PRId64 " bytes in size",
174                    MIN_NVRAM_SIZE, MAX_NVRAM_SIZE);
175         return;
176     }
177 
178     if (nvram->blk) {
179         int alen = blk_pread(nvram->blk, 0, nvram->buf, nvram->size);
180 
181         if (alen != nvram->size) {
182             error_setg(errp, "can't read spapr-nvram contents");
183             return;
184         }
185     } else if (nb_prom_envs > 0) {
186         /* Create a system partition to pass the -prom-env variables */
187         chrp_nvram_create_system_partition(nvram->buf, MIN_NVRAM_SIZE / 4);
188         chrp_nvram_create_free_partition(&nvram->buf[MIN_NVRAM_SIZE / 4],
189                                          nvram->size - MIN_NVRAM_SIZE / 4);
190     }
191 
192     spapr_rtas_register(RTAS_NVRAM_FETCH, "nvram-fetch", rtas_nvram_fetch);
193     spapr_rtas_register(RTAS_NVRAM_STORE, "nvram-store", rtas_nvram_store);
194 }
195 
196 static int spapr_nvram_devnode(SpaprVioDevice *dev, void *fdt, int node_off)
197 {
198     SpaprNvram *nvram = VIO_SPAPR_NVRAM(dev);
199 
200     return fdt_setprop_cell(fdt, node_off, "#bytes", nvram->size);
201 }
202 
203 static int spapr_nvram_pre_load(void *opaque)
204 {
205     SpaprNvram *nvram = VIO_SPAPR_NVRAM(opaque);
206 
207     g_free(nvram->buf);
208     nvram->buf = NULL;
209     nvram->size = 0;
210 
211     return 0;
212 }
213 
214 static void postload_update_cb(void *opaque, int running, RunState state)
215 {
216     SpaprNvram *nvram = opaque;
217 
218     /* This is called after bdrv_invalidate_cache_all.  */
219 
220     qemu_del_vm_change_state_handler(nvram->vmstate);
221     nvram->vmstate = NULL;
222 
223     blk_pwrite(nvram->blk, 0, nvram->buf, nvram->size, 0);
224 }
225 
226 static int spapr_nvram_post_load(void *opaque, int version_id)
227 {
228     SpaprNvram *nvram = VIO_SPAPR_NVRAM(opaque);
229 
230     if (nvram->blk) {
231         nvram->vmstate = qemu_add_vm_change_state_handler(postload_update_cb,
232                                                           nvram);
233     }
234 
235     return 0;
236 }
237 
238 static const VMStateDescription vmstate_spapr_nvram = {
239     .name = "spapr_nvram",
240     .version_id = 1,
241     .minimum_version_id = 1,
242     .pre_load = spapr_nvram_pre_load,
243     .post_load = spapr_nvram_post_load,
244     .fields = (VMStateField[]) {
245         VMSTATE_UINT32(size, SpaprNvram),
246         VMSTATE_VBUFFER_ALLOC_UINT32(buf, SpaprNvram, 1, NULL, size),
247         VMSTATE_END_OF_LIST()
248     },
249 };
250 
251 static Property spapr_nvram_properties[] = {
252     DEFINE_SPAPR_PROPERTIES(SpaprNvram, sdev),
253     DEFINE_PROP_DRIVE("drive", SpaprNvram, blk),
254     DEFINE_PROP_END_OF_LIST(),
255 };
256 
257 static void spapr_nvram_class_init(ObjectClass *klass, void *data)
258 {
259     DeviceClass *dc = DEVICE_CLASS(klass);
260     SpaprVioDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
261 
262     k->realize = spapr_nvram_realize;
263     k->devnode = spapr_nvram_devnode;
264     k->dt_name = "nvram";
265     k->dt_type = "nvram";
266     k->dt_compatible = "qemu,spapr-nvram";
267     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
268     dc->props = spapr_nvram_properties;
269     dc->vmsd = &vmstate_spapr_nvram;
270     /* Reason: Internal device only, uses spapr_rtas_register() in realize() */
271     dc->user_creatable = false;
272 }
273 
274 static const TypeInfo spapr_nvram_type_info = {
275     .name          = TYPE_VIO_SPAPR_NVRAM,
276     .parent        = TYPE_VIO_SPAPR_DEVICE,
277     .instance_size = sizeof(SpaprNvram),
278     .class_init    = spapr_nvram_class_init,
279 };
280 
281 static void spapr_nvram_register_types(void)
282 {
283     type_register_static(&spapr_nvram_type_info);
284 }
285 
286 type_init(spapr_nvram_register_types)
287