xref: /qemu/hw/sd/cadence_sdhci.c (revision e924921f5cea55d20a90f1d8d7239d35427bef04)
1 /*
2  * Cadence SDHCI emulation
3  *
4  * Copyright (c) 2020 Wind River Systems, Inc.
5  *
6  * Author:
7  *   Bin Meng <bin.meng@windriver.com>
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 or
12  * (at your option) version 3 of the License.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 #include "qemu/osdep.h"
24 #include "qemu/bitops.h"
25 #include "qemu/error-report.h"
26 #include "qemu/log.h"
27 #include "qapi/error.h"
28 #include "migration/vmstate.h"
29 #include "hw/sd/cadence_sdhci.h"
30 #include "sdhci-internal.h"
31 
32 /* HRS - Host Register Set (specific to Cadence) */
33 
34 #define CADENCE_SDHCI_HRS00             0x00    /* general information */
35 #define CADENCE_SDHCI_HRS00_SWR             BIT(0)
36 #define CADENCE_SDHCI_HRS00_POR_VAL         0x00010000
37 
38 #define CADENCE_SDHCI_HRS04             0x10    /* PHY access port */
39 #define CADENCE_SDHCI_HRS04_WR              BIT(24)
40 #define CADENCE_SDHCI_HRS04_RD              BIT(25)
41 #define CADENCE_SDHCI_HRS04_ACK             BIT(26)
42 
43 #define CADENCE_SDHCI_HRS06             0x18    /* eMMC control */
44 #define CADENCE_SDHCI_HRS06_TUNE_UP         BIT(15)
45 
46 /* SRS - Slot Register Set (SDHCI-compatible) */
47 
48 #define CADENCE_SDHCI_SRS_BASE          0x200
49 
50 #define TO_REG(addr)    ((addr) / sizeof(uint32_t))
51 
52 static void cadence_sdhci_instance_init(Object *obj)
53 {
54     CadenceSDHCIState *s = CADENCE_SDHCI(obj);
55 
56     object_initialize_child(OBJECT(s), "generic-sdhci",
57                             &s->sdhci, TYPE_SYSBUS_SDHCI);
58 }
59 
60 static void cadence_sdhci_reset(DeviceState *dev)
61 {
62     CadenceSDHCIState *s = CADENCE_SDHCI(dev);
63 
64     memset(s->regs, 0, CADENCE_SDHCI_REG_SIZE);
65     s->regs[TO_REG(CADENCE_SDHCI_HRS00)] = CADENCE_SDHCI_HRS00_POR_VAL;
66 
67     device_cold_reset(DEVICE(&s->sdhci));
68 }
69 
70 static uint64_t cadence_sdhci_read(void *opaque, hwaddr addr, unsigned int size)
71 {
72     CadenceSDHCIState *s = opaque;
73     uint32_t val;
74 
75     val = s->regs[TO_REG(addr)];
76 
77     return (uint64_t)val;
78 }
79 
80 static void cadence_sdhci_write(void *opaque, hwaddr addr, uint64_t val,
81                                 unsigned int size)
82 {
83     CadenceSDHCIState *s = opaque;
84     uint32_t val32 = (uint32_t)val;
85 
86     switch (addr) {
87     case CADENCE_SDHCI_HRS00:
88         /*
89          * The only writable bit is SWR (software reset) and it automatically
90          * clears to zero, so essentially this register remains unchanged.
91          */
92         if (val32 & CADENCE_SDHCI_HRS00_SWR) {
93             cadence_sdhci_reset(DEVICE(s));
94         }
95 
96         break;
97     case CADENCE_SDHCI_HRS04:
98         /*
99          * Only emulate the ACK bit behavior when read or write transaction
100          * are requested.
101          */
102         if (val32 & (CADENCE_SDHCI_HRS04_WR | CADENCE_SDHCI_HRS04_RD)) {
103             val32 |= CADENCE_SDHCI_HRS04_ACK;
104         } else {
105             val32 &= ~CADENCE_SDHCI_HRS04_ACK;
106         }
107 
108         s->regs[TO_REG(addr)] = val32;
109         break;
110     case CADENCE_SDHCI_HRS06:
111         if (val32 & CADENCE_SDHCI_HRS06_TUNE_UP) {
112             val32 &= ~CADENCE_SDHCI_HRS06_TUNE_UP;
113         }
114 
115         s->regs[TO_REG(addr)] = val32;
116         break;
117     default:
118         s->regs[TO_REG(addr)] = val32;
119         break;
120     }
121 }
122 
123 static const MemoryRegionOps cadence_sdhci_ops = {
124     .read = cadence_sdhci_read,
125     .write = cadence_sdhci_write,
126     .endianness = DEVICE_NATIVE_ENDIAN,
127     .impl = {
128         .min_access_size = 4,
129         .max_access_size = 4,
130     },
131     .valid = {
132         .min_access_size = 4,
133         .max_access_size = 4,
134     }
135 };
136 
137 static void cadence_sdhci_realize(DeviceState *dev, Error **errp)
138 {
139     CadenceSDHCIState *s = CADENCE_SDHCI(dev);
140     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
141     SysBusDevice *sbd_sdhci = SYS_BUS_DEVICE(&s->sdhci);
142 
143     memory_region_init(&s->container, OBJECT(s),
144                        "cadence.sdhci-container", 0x1000);
145     sysbus_init_mmio(sbd, &s->container);
146 
147     memory_region_init_io(&s->iomem, OBJECT(s), &cadence_sdhci_ops,
148                           s, TYPE_CADENCE_SDHCI, CADENCE_SDHCI_REG_SIZE);
149     memory_region_add_subregion(&s->container, 0, &s->iomem);
150 
151     sysbus_realize(sbd_sdhci, errp);
152     memory_region_add_subregion(&s->container, CADENCE_SDHCI_SRS_BASE,
153                                 sysbus_mmio_get_region(sbd_sdhci, 0));
154 
155     /* propagate irq and "sd-bus" from generic-sdhci */
156     sysbus_pass_irq(sbd, sbd_sdhci);
157     s->bus = qdev_get_child_bus(DEVICE(sbd_sdhci), "sd-bus");
158 }
159 
160 static const VMStateDescription vmstate_cadence_sdhci = {
161     .name = TYPE_CADENCE_SDHCI,
162     .version_id = 1,
163     .fields = (VMStateField[]) {
164         VMSTATE_UINT32_ARRAY(regs, CadenceSDHCIState, CADENCE_SDHCI_NUM_REGS),
165         VMSTATE_END_OF_LIST(),
166     },
167 };
168 
169 static void cadence_sdhci_class_init(ObjectClass *classp, void *data)
170 {
171     DeviceClass *dc = DEVICE_CLASS(classp);
172 
173     dc->desc = "Cadence SD/SDIO/eMMC Host Controller (SD4HC)";
174     dc->realize = cadence_sdhci_realize;
175     dc->reset = cadence_sdhci_reset;
176     dc->vmsd = &vmstate_cadence_sdhci;
177 }
178 
179 static TypeInfo cadence_sdhci_info = {
180     .name          = TYPE_CADENCE_SDHCI,
181     .parent        = TYPE_SYS_BUS_DEVICE,
182     .instance_size = sizeof(CadenceSDHCIState),
183     .instance_init = cadence_sdhci_instance_init,
184     .class_init    = cadence_sdhci_class_init,
185 };
186 
187 static void cadence_sdhci_register_types(void)
188 {
189     type_register_static(&cadence_sdhci_info);
190 }
191 
192 type_init(cadence_sdhci_register_types)
193