1 /*
2 * QEMU SiFive U OTP (One-Time Programmable) Memory interface
3 *
4 * Copyright (c) 2019 Bin Meng <bmeng.cn@gmail.com>
5 *
6 * Simple model of the OTP to emulate register reads made by the SDK BSP
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2 or later, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "hw/qdev-properties.h"
24 #include "hw/qdev-properties-system.h"
25 #include "hw/sysbus.h"
26 #include "qemu/error-report.h"
27 #include "qemu/log.h"
28 #include "qemu/module.h"
29 #include "hw/misc/sifive_u_otp.h"
30 #include "sysemu/blockdev.h"
31 #include "sysemu/block-backend.h"
32
33 #define WRITTEN_BIT_ON 0x1
34
35 #define SET_FUSEARRAY_BIT(map, i, off, bit) \
36 map[i] = bit ? (map[i] | bit << off) : (map[i] & ~(0x1 << off))
37
38 #define GET_FUSEARRAY_BIT(map, i, off) \
39 ((map[i] >> off) & 0x1)
40
sifive_u_otp_read(void * opaque,hwaddr addr,unsigned int size)41 static uint64_t sifive_u_otp_read(void *opaque, hwaddr addr, unsigned int size)
42 {
43 SiFiveUOTPState *s = opaque;
44
45 switch (addr) {
46 case SIFIVE_U_OTP_PA:
47 return s->pa;
48 case SIFIVE_U_OTP_PAIO:
49 return s->paio;
50 case SIFIVE_U_OTP_PAS:
51 return s->pas;
52 case SIFIVE_U_OTP_PCE:
53 return s->pce;
54 case SIFIVE_U_OTP_PCLK:
55 return s->pclk;
56 case SIFIVE_U_OTP_PDIN:
57 return s->pdin;
58 case SIFIVE_U_OTP_PDOUT:
59 if ((s->pce & SIFIVE_U_OTP_PCE_EN) &&
60 (s->pdstb & SIFIVE_U_OTP_PDSTB_EN) &&
61 (s->ptrim & SIFIVE_U_OTP_PTRIM_EN)) {
62
63 /* read from backend */
64 if (s->blk) {
65 int32_t buf;
66
67 if (blk_pread(s->blk, s->pa * SIFIVE_U_OTP_FUSE_WORD,
68 SIFIVE_U_OTP_FUSE_WORD, &buf, 0) < 0) {
69 error_report("read error index<%d>", s->pa);
70 return 0xff;
71 }
72
73 return buf;
74 }
75
76 return s->fuse[s->pa & SIFIVE_U_OTP_PA_MASK];
77 } else {
78 return 0xff;
79 }
80 case SIFIVE_U_OTP_PDSTB:
81 return s->pdstb;
82 case SIFIVE_U_OTP_PPROG:
83 return s->pprog;
84 case SIFIVE_U_OTP_PTC:
85 return s->ptc;
86 case SIFIVE_U_OTP_PTM:
87 return s->ptm;
88 case SIFIVE_U_OTP_PTM_REP:
89 return s->ptm_rep;
90 case SIFIVE_U_OTP_PTR:
91 return s->ptr;
92 case SIFIVE_U_OTP_PTRIM:
93 return s->ptrim;
94 case SIFIVE_U_OTP_PWE:
95 return s->pwe;
96 }
97
98 qemu_log_mask(LOG_GUEST_ERROR, "%s: read: addr=0x%" HWADDR_PRIx "\n",
99 __func__, addr);
100 return 0;
101 }
102
sifive_u_otp_write(void * opaque,hwaddr addr,uint64_t val64,unsigned int size)103 static void sifive_u_otp_write(void *opaque, hwaddr addr,
104 uint64_t val64, unsigned int size)
105 {
106 SiFiveUOTPState *s = opaque;
107 uint32_t val32 = (uint32_t)val64;
108
109 switch (addr) {
110 case SIFIVE_U_OTP_PA:
111 s->pa = val32 & SIFIVE_U_OTP_PA_MASK;
112 break;
113 case SIFIVE_U_OTP_PAIO:
114 s->paio = val32;
115 break;
116 case SIFIVE_U_OTP_PAS:
117 s->pas = val32;
118 break;
119 case SIFIVE_U_OTP_PCE:
120 s->pce = val32;
121 break;
122 case SIFIVE_U_OTP_PCLK:
123 s->pclk = val32;
124 break;
125 case SIFIVE_U_OTP_PDIN:
126 s->pdin = val32;
127 break;
128 case SIFIVE_U_OTP_PDOUT:
129 /* read-only */
130 break;
131 case SIFIVE_U_OTP_PDSTB:
132 s->pdstb = val32;
133 break;
134 case SIFIVE_U_OTP_PPROG:
135 s->pprog = val32;
136 break;
137 case SIFIVE_U_OTP_PTC:
138 s->ptc = val32;
139 break;
140 case SIFIVE_U_OTP_PTM:
141 s->ptm = val32;
142 break;
143 case SIFIVE_U_OTP_PTM_REP:
144 s->ptm_rep = val32;
145 break;
146 case SIFIVE_U_OTP_PTR:
147 s->ptr = val32;
148 break;
149 case SIFIVE_U_OTP_PTRIM:
150 s->ptrim = val32;
151 break;
152 case SIFIVE_U_OTP_PWE:
153 s->pwe = val32 & SIFIVE_U_OTP_PWE_EN;
154
155 /* PWE is enabled. Ignore PAS=1 (no redundancy cell) */
156 if (s->pwe && !s->pas) {
157 if (GET_FUSEARRAY_BIT(s->fuse_wo, s->pa, s->paio)) {
158 qemu_log_mask(LOG_GUEST_ERROR,
159 "write once error: idx<%u>, bit<%u>\n",
160 s->pa, s->paio);
161 break;
162 }
163
164 /* write bit data */
165 SET_FUSEARRAY_BIT(s->fuse, s->pa, s->paio, s->pdin);
166
167 /* write to backend */
168 if (s->blk) {
169 if (blk_pwrite(s->blk, s->pa * SIFIVE_U_OTP_FUSE_WORD,
170 SIFIVE_U_OTP_FUSE_WORD, &s->fuse[s->pa], 0)
171 < 0) {
172 error_report("write error index<%d>", s->pa);
173 }
174 }
175
176 /* update written bit */
177 SET_FUSEARRAY_BIT(s->fuse_wo, s->pa, s->paio, WRITTEN_BIT_ON);
178 }
179
180 break;
181 default:
182 qemu_log_mask(LOG_GUEST_ERROR, "%s: bad write: addr=0x%" HWADDR_PRIx
183 " v=0x%x\n", __func__, addr, val32);
184 }
185 }
186
187 static const MemoryRegionOps sifive_u_otp_ops = {
188 .read = sifive_u_otp_read,
189 .write = sifive_u_otp_write,
190 .endianness = DEVICE_NATIVE_ENDIAN,
191 .valid = {
192 .min_access_size = 4,
193 .max_access_size = 4
194 }
195 };
196
197 static Property sifive_u_otp_properties[] = {
198 DEFINE_PROP_UINT32("serial", SiFiveUOTPState, serial, 0),
199 DEFINE_PROP_DRIVE("drive", SiFiveUOTPState, blk),
200 DEFINE_PROP_END_OF_LIST(),
201 };
202
sifive_u_otp_realize(DeviceState * dev,Error ** errp)203 static void sifive_u_otp_realize(DeviceState *dev, Error **errp)
204 {
205 SiFiveUOTPState *s = SIFIVE_U_OTP(dev);
206 DriveInfo *dinfo;
207
208 memory_region_init_io(&s->mmio, OBJECT(dev), &sifive_u_otp_ops, s,
209 TYPE_SIFIVE_U_OTP, SIFIVE_U_OTP_REG_SIZE);
210 sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
211
212 dinfo = drive_get(IF_PFLASH, 0, 0);
213 if (dinfo) {
214 int ret;
215 uint64_t perm;
216 int filesize;
217 BlockBackend *blk;
218
219 blk = blk_by_legacy_dinfo(dinfo);
220 filesize = SIFIVE_U_OTP_NUM_FUSES * SIFIVE_U_OTP_FUSE_WORD;
221 if (blk_getlength(blk) < filesize) {
222 error_setg(errp, "OTP drive size < 16K");
223 return;
224 }
225
226 qdev_prop_set_drive_err(dev, "drive", blk, errp);
227
228 if (s->blk) {
229 perm = BLK_PERM_CONSISTENT_READ |
230 (blk_supports_write_perm(s->blk) ? BLK_PERM_WRITE : 0);
231 ret = blk_set_perm(s->blk, perm, BLK_PERM_ALL, errp);
232 if (ret < 0) {
233 return;
234 }
235
236 if (blk_pread(s->blk, 0, filesize, s->fuse, 0) < 0) {
237 error_setg(errp, "failed to read the initial flash content");
238 return;
239 }
240 }
241 }
242
243 /* Initialize all fuses' initial value to 0xFFs */
244 memset(s->fuse, 0xff, sizeof(s->fuse));
245
246 /* Make a valid content of serial number */
247 s->fuse[SIFIVE_U_OTP_SERIAL_ADDR] = s->serial;
248 s->fuse[SIFIVE_U_OTP_SERIAL_ADDR + 1] = ~(s->serial);
249
250 if (s->blk) {
251 /* Put serial number to backend as well*/
252 uint32_t serial_data;
253 int index = SIFIVE_U_OTP_SERIAL_ADDR;
254
255 serial_data = s->serial;
256 if (blk_pwrite(s->blk, index * SIFIVE_U_OTP_FUSE_WORD,
257 SIFIVE_U_OTP_FUSE_WORD, &serial_data, 0) < 0) {
258 error_setg(errp, "failed to write index<%d>", index);
259 return;
260 }
261
262 serial_data = ~(s->serial);
263 if (blk_pwrite(s->blk, (index + 1) * SIFIVE_U_OTP_FUSE_WORD,
264 SIFIVE_U_OTP_FUSE_WORD, &serial_data, 0) < 0) {
265 error_setg(errp, "failed to write index<%d>", index + 1);
266 return;
267 }
268 }
269
270 /* Initialize write-once map */
271 memset(s->fuse_wo, 0x00, sizeof(s->fuse_wo));
272 }
273
sifive_u_otp_class_init(ObjectClass * klass,void * data)274 static void sifive_u_otp_class_init(ObjectClass *klass, void *data)
275 {
276 DeviceClass *dc = DEVICE_CLASS(klass);
277
278 device_class_set_props(dc, sifive_u_otp_properties);
279 dc->realize = sifive_u_otp_realize;
280 }
281
282 static const TypeInfo sifive_u_otp_info = {
283 .name = TYPE_SIFIVE_U_OTP,
284 .parent = TYPE_SYS_BUS_DEVICE,
285 .instance_size = sizeof(SiFiveUOTPState),
286 .class_init = sifive_u_otp_class_init,
287 };
288
sifive_u_otp_register_types(void)289 static void sifive_u_otp_register_types(void)
290 {
291 type_register_static(&sifive_u_otp_info);
292 }
293
294 type_init(sifive_u_otp_register_types)
295