xref: /openbmc/qemu/hw/sd/cadence_sdhci.c (revision e4082063)
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 "qapi/error.h"
27 #include "migration/vmstate.h"
28 #include "hw/sd/cadence_sdhci.h"
29 #include "sdhci-internal.h"
30 
31 /* HRS - Host Register Set (specific to Cadence) */
32 
33 #define CADENCE_SDHCI_HRS00             0x00    /* general information */
34 #define CADENCE_SDHCI_HRS00_SWR             BIT(0)
35 #define CADENCE_SDHCI_HRS00_POR_VAL         0x00010000
36 
37 #define CADENCE_SDHCI_HRS04             0x10    /* PHY access port */
38 #define CADENCE_SDHCI_HRS04_WR              BIT(24)
39 #define CADENCE_SDHCI_HRS04_RD              BIT(25)
40 #define CADENCE_SDHCI_HRS04_ACK             BIT(26)
41 
42 #define CADENCE_SDHCI_HRS06             0x18    /* eMMC control */
43 #define CADENCE_SDHCI_HRS06_TUNE_UP         BIT(15)
44 
45 /* SRS - Slot Register Set (SDHCI-compatible) */
46 
47 #define CADENCE_SDHCI_SRS_BASE          0x200
48 
49 #define TO_REG(addr)    ((addr) / sizeof(uint32_t))
50 
51 static void cadence_sdhci_instance_init(Object *obj)
52 {
53     CadenceSDHCIState *s = CADENCE_SDHCI(obj);
54 
55     object_initialize_child(OBJECT(s), "generic-sdhci",
56                             &s->sdhci, TYPE_SYSBUS_SDHCI);
57 }
58 
59 static void cadence_sdhci_reset(DeviceState *dev)
60 {
61     CadenceSDHCIState *s = CADENCE_SDHCI(dev);
62 
63     memset(s->regs, 0, CADENCE_SDHCI_REG_SIZE);
64     s->regs[TO_REG(CADENCE_SDHCI_HRS00)] = CADENCE_SDHCI_HRS00_POR_VAL;
65 
66     device_cold_reset(DEVICE(&s->sdhci));
67 }
68 
69 static uint64_t cadence_sdhci_read(void *opaque, hwaddr addr, unsigned int size)
70 {
71     CadenceSDHCIState *s = opaque;
72     uint32_t val;
73 
74     val = s->regs[TO_REG(addr)];
75 
76     return (uint64_t)val;
77 }
78 
79 static void cadence_sdhci_write(void *opaque, hwaddr addr, uint64_t val,
80                                 unsigned int size)
81 {
82     CadenceSDHCIState *s = opaque;
83     uint32_t val32 = (uint32_t)val;
84 
85     switch (addr) {
86     case CADENCE_SDHCI_HRS00:
87         /*
88          * The only writable bit is SWR (software reset) and it automatically
89          * clears to zero, so essentially this register remains unchanged.
90          */
91         if (val32 & CADENCE_SDHCI_HRS00_SWR) {
92             cadence_sdhci_reset(DEVICE(s));
93         }
94 
95         break;
96     case CADENCE_SDHCI_HRS04:
97         /*
98          * Only emulate the ACK bit behavior when read or write transaction
99          * are requested.
100          */
101         if (val32 & (CADENCE_SDHCI_HRS04_WR | CADENCE_SDHCI_HRS04_RD)) {
102             val32 |= CADENCE_SDHCI_HRS04_ACK;
103         } else {
104             val32 &= ~CADENCE_SDHCI_HRS04_ACK;
105         }
106 
107         s->regs[TO_REG(addr)] = val32;
108         break;
109     case CADENCE_SDHCI_HRS06:
110         if (val32 & CADENCE_SDHCI_HRS06_TUNE_UP) {
111             val32 &= ~CADENCE_SDHCI_HRS06_TUNE_UP;
112         }
113 
114         s->regs[TO_REG(addr)] = val32;
115         break;
116     default:
117         s->regs[TO_REG(addr)] = val32;
118         break;
119     }
120 }
121 
122 static const MemoryRegionOps cadence_sdhci_ops = {
123     .read = cadence_sdhci_read,
124     .write = cadence_sdhci_write,
125     .endianness = DEVICE_NATIVE_ENDIAN,
126     .impl = {
127         .min_access_size = 4,
128         .max_access_size = 4,
129     },
130     .valid = {
131         .min_access_size = 4,
132         .max_access_size = 4,
133     }
134 };
135 
136 static void cadence_sdhci_realize(DeviceState *dev, Error **errp)
137 {
138     CadenceSDHCIState *s = CADENCE_SDHCI(dev);
139     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
140     SysBusDevice *sbd_sdhci = SYS_BUS_DEVICE(&s->sdhci);
141 
142     memory_region_init(&s->container, OBJECT(s),
143                        "cadence.sdhci-container", 0x1000);
144     sysbus_init_mmio(sbd, &s->container);
145 
146     memory_region_init_io(&s->iomem, OBJECT(s), &cadence_sdhci_ops,
147                           s, TYPE_CADENCE_SDHCI, CADENCE_SDHCI_REG_SIZE);
148     memory_region_add_subregion(&s->container, 0, &s->iomem);
149 
150     sysbus_realize(sbd_sdhci, errp);
151     memory_region_add_subregion(&s->container, CADENCE_SDHCI_SRS_BASE,
152                                 sysbus_mmio_get_region(sbd_sdhci, 0));
153 
154     /* propagate irq and "sd-bus" from generic-sdhci */
155     sysbus_pass_irq(sbd, sbd_sdhci);
156     s->bus = qdev_get_child_bus(DEVICE(sbd_sdhci), "sd-bus");
157 }
158 
159 static const VMStateDescription vmstate_cadence_sdhci = {
160     .name = TYPE_CADENCE_SDHCI,
161     .version_id = 1,
162     .fields = (VMStateField[]) {
163         VMSTATE_UINT32_ARRAY(regs, CadenceSDHCIState, CADENCE_SDHCI_NUM_REGS),
164         VMSTATE_END_OF_LIST(),
165     },
166 };
167 
168 static void cadence_sdhci_class_init(ObjectClass *classp, void *data)
169 {
170     DeviceClass *dc = DEVICE_CLASS(classp);
171 
172     dc->desc = "Cadence SD/SDIO/eMMC Host Controller (SD4HC)";
173     dc->realize = cadence_sdhci_realize;
174     dc->reset = cadence_sdhci_reset;
175     dc->vmsd = &vmstate_cadence_sdhci;
176 }
177 
178 static const TypeInfo cadence_sdhci_info = {
179     .name          = TYPE_CADENCE_SDHCI,
180     .parent        = TYPE_SYS_BUS_DEVICE,
181     .instance_size = sizeof(CadenceSDHCIState),
182     .instance_init = cadence_sdhci_instance_init,
183     .class_init    = cadence_sdhci_class_init,
184 };
185 
186 static void cadence_sdhci_register_types(void)
187 {
188     type_register_static(&cadence_sdhci_info);
189 }
190 
191 type_init(cadence_sdhci_register_types)
192