xref: /openbmc/qemu/hw/sd/cadence_sdhci.c (revision a47ef6e9)
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/irq.h"
30 #include "hw/sd/cadence_sdhci.h"
31 #include "sdhci-internal.h"
32 
33 /* HRS - Host Register Set (specific to Cadence) */
34 
35 #define CADENCE_SDHCI_HRS00             0x00    /* general information */
36 #define CADENCE_SDHCI_HRS00_SWR             BIT(0)
37 #define CADENCE_SDHCI_HRS00_POR_VAL         0x00010000
38 
39 #define CADENCE_SDHCI_HRS04             0x10    /* PHY access port */
40 #define CADENCE_SDHCI_HRS04_WR              BIT(24)
41 #define CADENCE_SDHCI_HRS04_RD              BIT(25)
42 #define CADENCE_SDHCI_HRS04_ACK             BIT(26)
43 
44 #define CADENCE_SDHCI_HRS06             0x18    /* eMMC control */
45 #define CADENCE_SDHCI_HRS06_TUNE_UP         BIT(15)
46 
47 /* SRS - Slot Register Set (SDHCI-compatible) */
48 
49 #define CADENCE_SDHCI_SRS_BASE          0x200
50 
51 #define TO_REG(addr)    ((addr) / sizeof(uint32_t))
52 
53 static void cadence_sdhci_instance_init(Object *obj)
54 {
55     CadenceSDHCIState *s = CADENCE_SDHCI(obj);
56 
57     object_initialize_child(OBJECT(s), "generic-sdhci",
58                             &s->sdhci, TYPE_SYSBUS_SDHCI);
59 }
60 
61 static void cadence_sdhci_reset(DeviceState *dev)
62 {
63     CadenceSDHCIState *s = CADENCE_SDHCI(dev);
64 
65     memset(s->regs, 0, CADENCE_SDHCI_REG_SIZE);
66     s->regs[TO_REG(CADENCE_SDHCI_HRS00)] = CADENCE_SDHCI_HRS00_POR_VAL;
67 
68     device_cold_reset(DEVICE(&s->sdhci));
69 }
70 
71 static uint64_t cadence_sdhci_read(void *opaque, hwaddr addr, unsigned int size)
72 {
73     CadenceSDHCIState *s = opaque;
74     uint32_t val;
75 
76     val = s->regs[TO_REG(addr)];
77 
78     return (uint64_t)val;
79 }
80 
81 static void cadence_sdhci_write(void *opaque, hwaddr addr, uint64_t val,
82                                 unsigned int size)
83 {
84     CadenceSDHCIState *s = opaque;
85     uint32_t val32 = (uint32_t)val;
86 
87     switch (addr) {
88     case CADENCE_SDHCI_HRS00:
89         /*
90          * The only writable bit is SWR (software reset) and it automatically
91          * clears to zero, so essentially this register remains unchanged.
92          */
93         if (val32 & CADENCE_SDHCI_HRS00_SWR) {
94             cadence_sdhci_reset(DEVICE(s));
95         }
96 
97         break;
98     case CADENCE_SDHCI_HRS04:
99         /*
100          * Only emulate the ACK bit behavior when read or write transaction
101          * are requested.
102          */
103         if (val32 & (CADENCE_SDHCI_HRS04_WR | CADENCE_SDHCI_HRS04_RD)) {
104             val32 |= CADENCE_SDHCI_HRS04_ACK;
105         } else {
106             val32 &= ~CADENCE_SDHCI_HRS04_ACK;
107         }
108 
109         s->regs[TO_REG(addr)] = val32;
110         break;
111     case CADENCE_SDHCI_HRS06:
112         if (val32 & CADENCE_SDHCI_HRS06_TUNE_UP) {
113             val32 &= ~CADENCE_SDHCI_HRS06_TUNE_UP;
114         }
115 
116         s->regs[TO_REG(addr)] = val32;
117         break;
118     default:
119         s->regs[TO_REG(addr)] = val32;
120         break;
121     }
122 }
123 
124 static const MemoryRegionOps cadence_sdhci_ops = {
125     .read = cadence_sdhci_read,
126     .write = cadence_sdhci_write,
127     .endianness = DEVICE_NATIVE_ENDIAN,
128     .impl = {
129         .min_access_size = 4,
130         .max_access_size = 4,
131     },
132     .valid = {
133         .min_access_size = 4,
134         .max_access_size = 4,
135     }
136 };
137 
138 static void cadence_sdhci_realize(DeviceState *dev, Error **errp)
139 {
140     CadenceSDHCIState *s = CADENCE_SDHCI(dev);
141     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
142     SysBusDevice *sbd_sdhci = SYS_BUS_DEVICE(&s->sdhci);
143 
144     memory_region_init(&s->container, OBJECT(s),
145                        "cadence.sdhci-container", 0x1000);
146     sysbus_init_mmio(sbd, &s->container);
147 
148     memory_region_init_io(&s->iomem, OBJECT(s), &cadence_sdhci_ops,
149                           s, TYPE_CADENCE_SDHCI, CADENCE_SDHCI_REG_SIZE);
150     memory_region_add_subregion(&s->container, 0, &s->iomem);
151 
152     sysbus_realize(sbd_sdhci, errp);
153     memory_region_add_subregion(&s->container, CADENCE_SDHCI_SRS_BASE,
154                                 sysbus_mmio_get_region(sbd_sdhci, 0));
155 
156     /* propagate irq and "sd-bus" from generic-sdhci */
157     sysbus_pass_irq(sbd, sbd_sdhci);
158     s->bus = qdev_get_child_bus(DEVICE(sbd_sdhci), "sd-bus");
159 }
160 
161 static const VMStateDescription vmstate_cadence_sdhci = {
162     .name = TYPE_CADENCE_SDHCI,
163     .version_id = 1,
164     .fields = (VMStateField[]) {
165         VMSTATE_UINT32_ARRAY(regs, CadenceSDHCIState, CADENCE_SDHCI_NUM_REGS),
166         VMSTATE_END_OF_LIST(),
167     },
168 };
169 
170 static void cadence_sdhci_class_init(ObjectClass *classp, void *data)
171 {
172     DeviceClass *dc = DEVICE_CLASS(classp);
173 
174     dc->desc = "Cadence SD/SDIO/eMMC Host Controller (SD4HC)";
175     dc->realize = cadence_sdhci_realize;
176     dc->reset = cadence_sdhci_reset;
177     dc->vmsd = &vmstate_cadence_sdhci;
178 }
179 
180 static TypeInfo cadence_sdhci_info = {
181     .name          = TYPE_CADENCE_SDHCI,
182     .parent        = TYPE_SYS_BUS_DEVICE,
183     .instance_size = sizeof(CadenceSDHCIState),
184     .instance_init = cadence_sdhci_instance_init,
185     .class_init    = cadence_sdhci_class_init,
186 };
187 
188 static void cadence_sdhci_register_types(void)
189 {
190     type_register_static(&cadence_sdhci_info);
191 }
192 
193 type_init(cadence_sdhci_register_types)
194