xref: /openbmc/qemu/hw/misc/sifive_u_prci.c (revision c00506aa)
1 /*
2  * QEMU SiFive U PRCI (Power, Reset, Clock, Interrupt)
3  *
4  * Copyright (c) 2019 Bin Meng <bmeng.cn@gmail.com>
5  *
6  * Simple model of the PRCI 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 "hw/sysbus.h"
23 #include "qemu/log.h"
24 #include "qemu/module.h"
25 #include "hw/misc/sifive_u_prci.h"
26 
27 static uint64_t sifive_u_prci_read(void *opaque, hwaddr addr, unsigned int size)
28 {
29     SiFiveUPRCIState *s = opaque;
30 
31     switch (addr) {
32     case SIFIVE_U_PRCI_HFXOSCCFG:
33         return s->hfxosccfg;
34     case SIFIVE_U_PRCI_COREPLLCFG0:
35         return s->corepllcfg0;
36     case SIFIVE_U_PRCI_DDRPLLCFG0:
37         return s->ddrpllcfg0;
38     case SIFIVE_U_PRCI_DDRPLLCFG1:
39         return s->ddrpllcfg1;
40     case SIFIVE_U_PRCI_GEMGXLPLLCFG0:
41         return s->gemgxlpllcfg0;
42     case SIFIVE_U_PRCI_GEMGXLPLLCFG1:
43         return s->gemgxlpllcfg1;
44     case SIFIVE_U_PRCI_CORECLKSEL:
45         return s->coreclksel;
46     case SIFIVE_U_PRCI_DEVICESRESET:
47         return s->devicesreset;
48     case SIFIVE_U_PRCI_CLKMUXSTATUS:
49         return s->clkmuxstatus;
50     }
51 
52     qemu_log_mask(LOG_GUEST_ERROR, "%s: read: addr=0x%" HWADDR_PRIx "\n",
53                   __func__, addr);
54 
55     return 0;
56 }
57 
58 static void sifive_u_prci_write(void *opaque, hwaddr addr,
59                                 uint64_t val64, unsigned int size)
60 {
61     SiFiveUPRCIState *s = opaque;
62     uint32_t val32 = (uint32_t)val64;
63 
64     switch (addr) {
65     case SIFIVE_U_PRCI_HFXOSCCFG:
66         s->hfxosccfg = val32;
67         /* OSC stays ready */
68         s->hfxosccfg |= SIFIVE_U_PRCI_HFXOSCCFG_RDY;
69         break;
70     case SIFIVE_U_PRCI_COREPLLCFG0:
71         s->corepllcfg0 = val32;
72         /* internal feedback */
73         s->corepllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_FSE;
74         /* PLL stays locked */
75         s->corepllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_LOCK;
76         break;
77     case SIFIVE_U_PRCI_DDRPLLCFG0:
78         s->ddrpllcfg0 = val32;
79         /* internal feedback */
80         s->ddrpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_FSE;
81         /* PLL stays locked */
82         s->ddrpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_LOCK;
83         break;
84     case SIFIVE_U_PRCI_DDRPLLCFG1:
85         s->ddrpllcfg1 = val32;
86         break;
87     case SIFIVE_U_PRCI_GEMGXLPLLCFG0:
88         s->gemgxlpllcfg0 = val32;
89         /* internal feedback */
90         s->gemgxlpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_FSE;
91         /* PLL stays locked */
92         s->gemgxlpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_LOCK;
93         break;
94     case SIFIVE_U_PRCI_GEMGXLPLLCFG1:
95         s->gemgxlpllcfg1 = val32;
96         break;
97     case SIFIVE_U_PRCI_CORECLKSEL:
98         s->coreclksel = val32;
99         break;
100     case SIFIVE_U_PRCI_DEVICESRESET:
101         s->devicesreset = val32;
102         break;
103     case SIFIVE_U_PRCI_CLKMUXSTATUS:
104         s->clkmuxstatus = val32;
105         break;
106     default:
107         qemu_log_mask(LOG_GUEST_ERROR, "%s: bad write: addr=0x%" HWADDR_PRIx
108                       " v=0x%x\n", __func__, addr, val32);
109     }
110 }
111 
112 static const MemoryRegionOps sifive_u_prci_ops = {
113     .read = sifive_u_prci_read,
114     .write = sifive_u_prci_write,
115     .endianness = DEVICE_NATIVE_ENDIAN,
116     .valid = {
117         .min_access_size = 4,
118         .max_access_size = 4
119     }
120 };
121 
122 static void sifive_u_prci_realize(DeviceState *dev, Error **errp)
123 {
124     SiFiveUPRCIState *s = SIFIVE_U_PRCI(dev);
125 
126     memory_region_init_io(&s->mmio, OBJECT(dev), &sifive_u_prci_ops, s,
127                           TYPE_SIFIVE_U_PRCI, SIFIVE_U_PRCI_REG_SIZE);
128     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
129 }
130 
131 static void sifive_u_prci_reset(DeviceState *dev)
132 {
133     SiFiveUPRCIState *s = SIFIVE_U_PRCI(dev);
134 
135     /* Initialize register to power-on-reset values */
136     s->hfxosccfg = SIFIVE_U_PRCI_HFXOSCCFG_RDY | SIFIVE_U_PRCI_HFXOSCCFG_EN;
137     s->corepllcfg0 = SIFIVE_U_PRCI_PLLCFG0_DIVR | SIFIVE_U_PRCI_PLLCFG0_DIVF |
138                      SIFIVE_U_PRCI_PLLCFG0_DIVQ | SIFIVE_U_PRCI_PLLCFG0_FSE |
139                      SIFIVE_U_PRCI_PLLCFG0_LOCK;
140     s->ddrpllcfg0 = SIFIVE_U_PRCI_PLLCFG0_DIVR | SIFIVE_U_PRCI_PLLCFG0_DIVF |
141                     SIFIVE_U_PRCI_PLLCFG0_DIVQ | SIFIVE_U_PRCI_PLLCFG0_FSE |
142                     SIFIVE_U_PRCI_PLLCFG0_LOCK;
143     s->gemgxlpllcfg0 = SIFIVE_U_PRCI_PLLCFG0_DIVR | SIFIVE_U_PRCI_PLLCFG0_DIVF |
144                        SIFIVE_U_PRCI_PLLCFG0_DIVQ | SIFIVE_U_PRCI_PLLCFG0_FSE |
145                        SIFIVE_U_PRCI_PLLCFG0_LOCK;
146     s->coreclksel = SIFIVE_U_PRCI_CORECLKSEL_HFCLK;
147 }
148 
149 static void sifive_u_prci_class_init(ObjectClass *klass, void *data)
150 {
151     DeviceClass *dc = DEVICE_CLASS(klass);
152 
153     dc->realize = sifive_u_prci_realize;
154     dc->reset = sifive_u_prci_reset;
155 }
156 
157 static const TypeInfo sifive_u_prci_info = {
158     .name          = TYPE_SIFIVE_U_PRCI,
159     .parent        = TYPE_SYS_BUS_DEVICE,
160     .instance_size = sizeof(SiFiveUPRCIState),
161     .class_init    = sifive_u_prci_class_init,
162 };
163 
164 static void sifive_u_prci_register_types(void)
165 {
166     type_register_static(&sifive_u_prci_info);
167 }
168 
169 type_init(sifive_u_prci_register_types)
170