xref: /qemu/hw/misc/mchp_pfsoc_sysreg.c (revision 2af4a82ab2cce3412ffc92cd4c96bd870e33bc8e)
1 /*
2  * Microchip PolarFire SoC SYSREG module 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/log.h"
26 #include "qapi/error.h"
27 #include "hw/irq.h"
28 #include "hw/sysbus.h"
29 #include "hw/misc/mchp_pfsoc_sysreg.h"
30 #include "system/runstate.h"
31 
32 #define MSS_RESET_CR    0x18
33 #define ENVM_CR         0xb8
34 #define MESSAGE_INT     0x118c
35 
mchp_pfsoc_sysreg_read(void * opaque,hwaddr offset,unsigned size)36 static uint64_t mchp_pfsoc_sysreg_read(void *opaque, hwaddr offset,
37                                        unsigned size)
38 {
39     uint32_t val = 0;
40 
41     switch (offset) {
42     case ENVM_CR:
43         /* Indicate the eNVM is running at the configured divider rate */
44         val = BIT(6);
45         break;
46     default:
47         qemu_log_mask(LOG_UNIMP, "%s: unimplemented device read "
48                       "(size %d, offset 0x%" HWADDR_PRIx ")\n",
49                       __func__, size, offset);
50         break;
51     }
52 
53     return val;
54 }
55 
mchp_pfsoc_sysreg_write(void * opaque,hwaddr offset,uint64_t value,unsigned size)56 static void mchp_pfsoc_sysreg_write(void *opaque, hwaddr offset,
57                                     uint64_t value, unsigned size)
58 {
59     MchpPfSoCSysregState *s = opaque;
60     switch (offset) {
61     case MSS_RESET_CR:
62         if (value == 0xdead) {
63             qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
64         }
65         break;
66     case MESSAGE_INT:
67         qemu_irq_lower(s->irq);
68         break;
69     default:
70         qemu_log_mask(LOG_UNIMP, "%s: unimplemented device write "
71                       "(size %d, value 0x%" PRIx64
72                       ", offset 0x%" HWADDR_PRIx ")\n",
73                       __func__, size, value, offset);
74     }
75 }
76 
77 static const MemoryRegionOps mchp_pfsoc_sysreg_ops = {
78     .read = mchp_pfsoc_sysreg_read,
79     .write = mchp_pfsoc_sysreg_write,
80     .endianness = DEVICE_LITTLE_ENDIAN,
81 };
82 
mchp_pfsoc_sysreg_realize(DeviceState * dev,Error ** errp)83 static void mchp_pfsoc_sysreg_realize(DeviceState *dev, Error **errp)
84 {
85     MchpPfSoCSysregState *s = MCHP_PFSOC_SYSREG(dev);
86 
87     memory_region_init_io(&s->sysreg, OBJECT(dev),
88                           &mchp_pfsoc_sysreg_ops, s,
89                           "mchp.pfsoc.sysreg",
90                           MCHP_PFSOC_SYSREG_REG_SIZE);
91     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->sysreg);
92     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq);
93 }
94 
mchp_pfsoc_sysreg_class_init(ObjectClass * klass,const void * data)95 static void mchp_pfsoc_sysreg_class_init(ObjectClass *klass, const void *data)
96 {
97     DeviceClass *dc = DEVICE_CLASS(klass);
98 
99     dc->desc = "Microchip PolarFire SoC SYSREG module";
100     dc->realize = mchp_pfsoc_sysreg_realize;
101 }
102 
103 static const TypeInfo mchp_pfsoc_sysreg_info = {
104     .name          = TYPE_MCHP_PFSOC_SYSREG,
105     .parent        = TYPE_SYS_BUS_DEVICE,
106     .instance_size = sizeof(MchpPfSoCSysregState),
107     .class_init    = mchp_pfsoc_sysreg_class_init,
108 };
109 
mchp_pfsoc_sysreg_register_types(void)110 static void mchp_pfsoc_sysreg_register_types(void)
111 {
112     type_register_static(&mchp_pfsoc_sysreg_info);
113 }
114 
115 type_init(mchp_pfsoc_sysreg_register_types)
116