xref: /openbmc/qemu/hw/misc/sifive_e_prci.c (revision a68694cd)
1 /*
2  * QEMU SiFive E PRCI (Power, Reset, Clock, Interrupt)
3  *
4  * Copyright (c) 2017 SiFive, Inc.
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 "qapi/error.h"
24 #include "qemu/log.h"
25 #include "qemu/module.h"
26 #include "hw/hw.h"
27 #include "hw/misc/sifive_e_prci.h"
28 
29 static uint64_t sifive_e_prci_read(void *opaque, hwaddr addr, unsigned int size)
30 {
31     SiFiveEPRCIState *s = opaque;
32     switch (addr) {
33     case SIFIVE_E_PRCI_HFROSCCFG:
34         return s->hfrosccfg;
35     case SIFIVE_E_PRCI_HFXOSCCFG:
36         return s->hfxosccfg;
37     case SIFIVE_E_PRCI_PLLCFG:
38         return s->pllcfg;
39     case SIFIVE_E_PRCI_PLLOUTDIV:
40         return s->plloutdiv;
41     }
42     qemu_log_mask(LOG_GUEST_ERROR, "%s: read: addr=0x%x\n",
43                   __func__, (int)addr);
44     return 0;
45 }
46 
47 static void sifive_e_prci_write(void *opaque, hwaddr addr,
48                                 uint64_t val64, unsigned int size)
49 {
50     SiFiveEPRCIState *s = opaque;
51     switch (addr) {
52     case SIFIVE_E_PRCI_HFROSCCFG:
53         s->hfrosccfg = (uint32_t) val64;
54         /* OSC stays ready */
55         s->hfrosccfg |= SIFIVE_E_PRCI_HFROSCCFG_RDY;
56         break;
57     case SIFIVE_E_PRCI_HFXOSCCFG:
58         s->hfxosccfg = (uint32_t) val64;
59         /* OSC stays ready */
60         s->hfxosccfg |= SIFIVE_E_PRCI_HFXOSCCFG_RDY;
61         break;
62     case SIFIVE_E_PRCI_PLLCFG:
63         s->pllcfg = (uint32_t) val64;
64         /* PLL stays locked */
65         s->pllcfg |= SIFIVE_E_PRCI_PLLCFG_LOCK;
66         break;
67     case SIFIVE_E_PRCI_PLLOUTDIV:
68         s->plloutdiv = (uint32_t) val64;
69         break;
70     default:
71         qemu_log_mask(LOG_GUEST_ERROR, "%s: bad write: addr=0x%x v=0x%x\n",
72                       __func__, (int)addr, (int)val64);
73     }
74 }
75 
76 static const MemoryRegionOps sifive_e_prci_ops = {
77     .read = sifive_e_prci_read,
78     .write = sifive_e_prci_write,
79     .endianness = DEVICE_NATIVE_ENDIAN,
80     .valid = {
81         .min_access_size = 4,
82         .max_access_size = 4
83     }
84 };
85 
86 static void sifive_e_prci_init(Object *obj)
87 {
88     SiFiveEPRCIState *s = SIFIVE_E_PRCI(obj);
89 
90     memory_region_init_io(&s->mmio, obj, &sifive_e_prci_ops, s,
91                           TYPE_SIFIVE_E_PRCI, SIFIVE_E_PRCI_REG_SIZE);
92     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
93 
94     s->hfrosccfg = (SIFIVE_E_PRCI_HFROSCCFG_RDY | SIFIVE_E_PRCI_HFROSCCFG_EN);
95     s->hfxosccfg = (SIFIVE_E_PRCI_HFXOSCCFG_RDY | SIFIVE_E_PRCI_HFXOSCCFG_EN);
96     s->pllcfg = (SIFIVE_E_PRCI_PLLCFG_REFSEL | SIFIVE_E_PRCI_PLLCFG_BYPASS |
97                  SIFIVE_E_PRCI_PLLCFG_LOCK);
98     s->plloutdiv = SIFIVE_E_PRCI_PLLOUTDIV_DIV1;
99 }
100 
101 static const TypeInfo sifive_e_prci_info = {
102     .name          = TYPE_SIFIVE_E_PRCI,
103     .parent        = TYPE_SYS_BUS_DEVICE,
104     .instance_size = sizeof(SiFiveEPRCIState),
105     .instance_init = sifive_e_prci_init,
106 };
107 
108 static void sifive_e_prci_register_types(void)
109 {
110     type_register_static(&sifive_e_prci_info);
111 }
112 
113 type_init(sifive_e_prci_register_types)
114 
115 
116 /*
117  * Create PRCI device.
118  */
119 DeviceState *sifive_e_prci_create(hwaddr addr)
120 {
121     DeviceState *dev = qdev_new(TYPE_SIFIVE_E_PRCI);
122     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
123     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
124     return dev;
125 }
126