xref: /openbmc/qemu/hw/misc/allwinner-h3-dramc.c (revision bf616ce4)
1 /*
2  * Allwinner H3 SDRAM Controller emulation
3  *
4  * Copyright (C) 2019 Niek Linnenbank <nieklinnenbank@gmail.com>
5  *
6  * This program is free software: you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation, either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/units.h"
22 #include "qemu/error-report.h"
23 #include "hw/sysbus.h"
24 #include "migration/vmstate.h"
25 #include "qemu/log.h"
26 #include "qemu/module.h"
27 #include "exec/address-spaces.h"
28 #include "hw/qdev-properties.h"
29 #include "qapi/error.h"
30 #include "hw/misc/allwinner-h3-dramc.h"
31 #include "trace.h"
32 
33 #define REG_INDEX(offset)    (offset / sizeof(uint32_t))
34 
35 /* DRAMCOM register offsets */
36 enum {
37     REG_DRAMCOM_CR    = 0x0000, /* Control Register */
38 };
39 
40 /* DRAMCTL register offsets */
41 enum {
42     REG_DRAMCTL_PIR   = 0x0000, /* PHY Initialization Register */
43     REG_DRAMCTL_PGSR  = 0x0010, /* PHY General Status Register */
44     REG_DRAMCTL_STATR = 0x0018, /* Status Register */
45 };
46 
47 /* DRAMCTL register flags */
48 enum {
49     REG_DRAMCTL_PGSR_INITDONE = (1 << 0),
50 };
51 
52 enum {
53     REG_DRAMCTL_STATR_ACTIVE  = (1 << 0),
54 };
55 
56 static void allwinner_h3_dramc_map_rows(AwH3DramCtlState *s, uint8_t row_bits,
57                                         uint8_t bank_bits, uint16_t page_size)
58 {
59     /*
60      * This function simulates row addressing behavior when bootloader
61      * software attempts to detect the amount of available SDRAM. In U-Boot
62      * the controller is configured with the widest row addressing available.
63      * Then a pattern is written to RAM at an offset on the row boundary size.
64      * If the value read back equals the value read back from the
65      * start of RAM, the bootloader knows the amount of row bits.
66      *
67      * This function inserts a mirrored memory region when the configured row
68      * bits are not matching the actual emulated memory, to simulate the
69      * same behavior on hardware as expected by the bootloader.
70      */
71     uint8_t row_bits_actual = 0;
72 
73     /* Calculate the actual row bits using the ram_size property */
74     for (uint8_t i = 8; i < 12; i++) {
75         if (1 << i == s->ram_size) {
76             row_bits_actual = i + 3;
77             break;
78         }
79     }
80 
81     if (s->ram_size == (1 << (row_bits - 3))) {
82         /* When row bits is the expected value, remove the mirror */
83         memory_region_set_enabled(&s->row_mirror_alias, false);
84         trace_allwinner_h3_dramc_rowmirror_disable();
85 
86     } else if (row_bits_actual) {
87         /* Row bits not matching ram_size, install the rows mirror */
88         hwaddr row_mirror = s->ram_addr + ((1ULL << (row_bits_actual +
89                                                      bank_bits)) * page_size);
90 
91         memory_region_set_enabled(&s->row_mirror_alias, true);
92         memory_region_set_address(&s->row_mirror_alias, row_mirror);
93 
94         trace_allwinner_h3_dramc_rowmirror_enable(row_mirror);
95     }
96 }
97 
98 static uint64_t allwinner_h3_dramcom_read(void *opaque, hwaddr offset,
99                                           unsigned size)
100 {
101     const AwH3DramCtlState *s = AW_H3_DRAMC(opaque);
102     const uint32_t idx = REG_INDEX(offset);
103 
104     if (idx >= AW_H3_DRAMCOM_REGS_NUM) {
105         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
106                       __func__, (uint32_t)offset);
107         return 0;
108     }
109 
110     trace_allwinner_h3_dramcom_read(offset, s->dramcom[idx], size);
111 
112     return s->dramcom[idx];
113 }
114 
115 static void allwinner_h3_dramcom_write(void *opaque, hwaddr offset,
116                                        uint64_t val, unsigned size)
117 {
118     AwH3DramCtlState *s = AW_H3_DRAMC(opaque);
119     const uint32_t idx = REG_INDEX(offset);
120 
121     trace_allwinner_h3_dramcom_write(offset, val, size);
122 
123     if (idx >= AW_H3_DRAMCOM_REGS_NUM) {
124         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
125                       __func__, (uint32_t)offset);
126         return;
127     }
128 
129     switch (offset) {
130     case REG_DRAMCOM_CR:   /* Control Register */
131         allwinner_h3_dramc_map_rows(s, ((val >> 4) & 0xf) + 1,
132                                        ((val >> 2) & 0x1) + 2,
133                                        1 << (((val >> 8) & 0xf) + 3));
134         break;
135     default:
136         break;
137     };
138 
139     s->dramcom[idx] = (uint32_t) val;
140 }
141 
142 static uint64_t allwinner_h3_dramctl_read(void *opaque, hwaddr offset,
143                                           unsigned size)
144 {
145     const AwH3DramCtlState *s = AW_H3_DRAMC(opaque);
146     const uint32_t idx = REG_INDEX(offset);
147 
148     if (idx >= AW_H3_DRAMCTL_REGS_NUM) {
149         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
150                       __func__, (uint32_t)offset);
151         return 0;
152     }
153 
154     trace_allwinner_h3_dramctl_read(offset, s->dramctl[idx], size);
155 
156     return s->dramctl[idx];
157 }
158 
159 static void allwinner_h3_dramctl_write(void *opaque, hwaddr offset,
160                                        uint64_t val, unsigned size)
161 {
162     AwH3DramCtlState *s = AW_H3_DRAMC(opaque);
163     const uint32_t idx = REG_INDEX(offset);
164 
165     trace_allwinner_h3_dramctl_write(offset, val, size);
166 
167     if (idx >= AW_H3_DRAMCTL_REGS_NUM) {
168         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
169                       __func__, (uint32_t)offset);
170         return;
171     }
172 
173     switch (offset) {
174     case REG_DRAMCTL_PIR:    /* PHY Initialization Register */
175         s->dramctl[REG_INDEX(REG_DRAMCTL_PGSR)] |= REG_DRAMCTL_PGSR_INITDONE;
176         s->dramctl[REG_INDEX(REG_DRAMCTL_STATR)] |= REG_DRAMCTL_STATR_ACTIVE;
177         break;
178     default:
179         break;
180     }
181 
182     s->dramctl[idx] = (uint32_t) val;
183 }
184 
185 static uint64_t allwinner_h3_dramphy_read(void *opaque, hwaddr offset,
186                                           unsigned size)
187 {
188     const AwH3DramCtlState *s = AW_H3_DRAMC(opaque);
189     const uint32_t idx = REG_INDEX(offset);
190 
191     if (idx >= AW_H3_DRAMPHY_REGS_NUM) {
192         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
193                       __func__, (uint32_t)offset);
194         return 0;
195     }
196 
197     trace_allwinner_h3_dramphy_read(offset, s->dramphy[idx], size);
198 
199     return s->dramphy[idx];
200 }
201 
202 static void allwinner_h3_dramphy_write(void *opaque, hwaddr offset,
203                                        uint64_t val, unsigned size)
204 {
205     AwH3DramCtlState *s = AW_H3_DRAMC(opaque);
206     const uint32_t idx = REG_INDEX(offset);
207 
208     trace_allwinner_h3_dramphy_write(offset, val, size);
209 
210     if (idx >= AW_H3_DRAMPHY_REGS_NUM) {
211         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
212                       __func__, (uint32_t)offset);
213         return;
214     }
215 
216     s->dramphy[idx] = (uint32_t) val;
217 }
218 
219 static const MemoryRegionOps allwinner_h3_dramcom_ops = {
220     .read = allwinner_h3_dramcom_read,
221     .write = allwinner_h3_dramcom_write,
222     .endianness = DEVICE_NATIVE_ENDIAN,
223     .valid = {
224         .min_access_size = 4,
225         .max_access_size = 4,
226     },
227     .impl.min_access_size = 4,
228 };
229 
230 static const MemoryRegionOps allwinner_h3_dramctl_ops = {
231     .read = allwinner_h3_dramctl_read,
232     .write = allwinner_h3_dramctl_write,
233     .endianness = DEVICE_NATIVE_ENDIAN,
234     .valid = {
235         .min_access_size = 4,
236         .max_access_size = 4,
237     },
238     .impl.min_access_size = 4,
239 };
240 
241 static const MemoryRegionOps allwinner_h3_dramphy_ops = {
242     .read = allwinner_h3_dramphy_read,
243     .write = allwinner_h3_dramphy_write,
244     .endianness = DEVICE_NATIVE_ENDIAN,
245     .valid = {
246         .min_access_size = 4,
247         .max_access_size = 4,
248     },
249     .impl.min_access_size = 4,
250 };
251 
252 static void allwinner_h3_dramc_reset(DeviceState *dev)
253 {
254     AwH3DramCtlState *s = AW_H3_DRAMC(dev);
255 
256     /* Set default values for registers */
257     memset(&s->dramcom, 0, sizeof(s->dramcom));
258     memset(&s->dramctl, 0, sizeof(s->dramctl));
259     memset(&s->dramphy, 0, sizeof(s->dramphy));
260 }
261 
262 static void allwinner_h3_dramc_realize(DeviceState *dev, Error **errp)
263 {
264     AwH3DramCtlState *s = AW_H3_DRAMC(dev);
265 
266     /* Only power of 2 RAM sizes from 256MiB up to 2048MiB are supported */
267     for (uint8_t i = 8; i < 13; i++) {
268         if (1 << i == s->ram_size) {
269             break;
270         } else if (i == 12) {
271             error_report("%s: ram-size %u MiB is not supported",
272                           __func__, s->ram_size);
273             exit(1);
274         }
275     }
276 
277     /* Setup row mirror mappings */
278     memory_region_init_ram(&s->row_mirror, OBJECT(s),
279                            "allwinner-h3-dramc.row-mirror",
280                             4 * KiB, &error_abort);
281     memory_region_add_subregion_overlap(get_system_memory(), s->ram_addr,
282                                        &s->row_mirror, 10);
283 
284     memory_region_init_alias(&s->row_mirror_alias, OBJECT(s),
285                             "allwinner-h3-dramc.row-mirror-alias",
286                             &s->row_mirror, 0, 4 * KiB);
287     memory_region_add_subregion_overlap(get_system_memory(),
288                                         s->ram_addr + 1 * MiB,
289                                        &s->row_mirror_alias, 10);
290     memory_region_set_enabled(&s->row_mirror_alias, false);
291 }
292 
293 static void allwinner_h3_dramc_init(Object *obj)
294 {
295     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
296     AwH3DramCtlState *s = AW_H3_DRAMC(obj);
297 
298     /* DRAMCOM registers */
299     memory_region_init_io(&s->dramcom_iomem, OBJECT(s),
300                           &allwinner_h3_dramcom_ops, s,
301                            TYPE_AW_H3_DRAMC, 4 * KiB);
302     sysbus_init_mmio(sbd, &s->dramcom_iomem);
303 
304     /* DRAMCTL registers */
305     memory_region_init_io(&s->dramctl_iomem, OBJECT(s),
306                           &allwinner_h3_dramctl_ops, s,
307                            TYPE_AW_H3_DRAMC, 4 * KiB);
308     sysbus_init_mmio(sbd, &s->dramctl_iomem);
309 
310     /* DRAMPHY registers */
311     memory_region_init_io(&s->dramphy_iomem, OBJECT(s),
312                           &allwinner_h3_dramphy_ops, s,
313                           TYPE_AW_H3_DRAMC, 4 * KiB);
314     sysbus_init_mmio(sbd, &s->dramphy_iomem);
315 }
316 
317 static Property allwinner_h3_dramc_properties[] = {
318     DEFINE_PROP_UINT64("ram-addr", AwH3DramCtlState, ram_addr, 0x0),
319     DEFINE_PROP_UINT32("ram-size", AwH3DramCtlState, ram_size, 256 * MiB),
320     DEFINE_PROP_END_OF_LIST()
321 };
322 
323 static const VMStateDescription allwinner_h3_dramc_vmstate = {
324     .name = "allwinner-h3-dramc",
325     .version_id = 1,
326     .minimum_version_id = 1,
327     .fields = (const VMStateField[]) {
328         VMSTATE_UINT32_ARRAY(dramcom, AwH3DramCtlState, AW_H3_DRAMCOM_REGS_NUM),
329         VMSTATE_UINT32_ARRAY(dramctl, AwH3DramCtlState, AW_H3_DRAMCTL_REGS_NUM),
330         VMSTATE_UINT32_ARRAY(dramphy, AwH3DramCtlState, AW_H3_DRAMPHY_REGS_NUM),
331         VMSTATE_END_OF_LIST()
332     }
333 };
334 
335 static void allwinner_h3_dramc_class_init(ObjectClass *klass, void *data)
336 {
337     DeviceClass *dc = DEVICE_CLASS(klass);
338 
339     dc->reset = allwinner_h3_dramc_reset;
340     dc->vmsd = &allwinner_h3_dramc_vmstate;
341     dc->realize = allwinner_h3_dramc_realize;
342     device_class_set_props(dc, allwinner_h3_dramc_properties);
343 }
344 
345 static const TypeInfo allwinner_h3_dramc_info = {
346     .name          = TYPE_AW_H3_DRAMC,
347     .parent        = TYPE_SYS_BUS_DEVICE,
348     .instance_init = allwinner_h3_dramc_init,
349     .instance_size = sizeof(AwH3DramCtlState),
350     .class_init    = allwinner_h3_dramc_class_init,
351 };
352 
353 static void allwinner_h3_dramc_register(void)
354 {
355     type_register_static(&allwinner_h3_dramc_info);
356 }
357 
358 type_init(allwinner_h3_dramc_register)
359