xref: /openbmc/qemu/hw/misc/mchp_pfsoc_sysreg.c (revision bad5cfcd)
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 
31 #define ENVM_CR         0xb8
32 #define MESSAGE_INT     0x118c
33 
34 static uint64_t mchp_pfsoc_sysreg_read(void *opaque, hwaddr offset,
35                                        unsigned size)
36 {
37     uint32_t val = 0;
38 
39     switch (offset) {
40     case ENVM_CR:
41         /* Indicate the eNVM is running at the configured divider rate */
42         val = BIT(6);
43         break;
44     default:
45         qemu_log_mask(LOG_UNIMP, "%s: unimplemented device read "
46                       "(size %d, offset 0x%" HWADDR_PRIx ")\n",
47                       __func__, size, offset);
48         break;
49     }
50 
51     return val;
52 }
53 
54 static void mchp_pfsoc_sysreg_write(void *opaque, hwaddr offset,
55                                     uint64_t value, unsigned size)
56 {
57     MchpPfSoCSysregState *s = opaque;
58     switch (offset) {
59     case MESSAGE_INT:
60         qemu_irq_lower(s->irq);
61         break;
62     default:
63         qemu_log_mask(LOG_UNIMP, "%s: unimplemented device write "
64                       "(size %d, value 0x%" PRIx64
65                       ", offset 0x%" HWADDR_PRIx ")\n",
66                       __func__, size, value, offset);
67     }
68 }
69 
70 static const MemoryRegionOps mchp_pfsoc_sysreg_ops = {
71     .read = mchp_pfsoc_sysreg_read,
72     .write = mchp_pfsoc_sysreg_write,
73     .endianness = DEVICE_LITTLE_ENDIAN,
74 };
75 
76 static void mchp_pfsoc_sysreg_realize(DeviceState *dev, Error **errp)
77 {
78     MchpPfSoCSysregState *s = MCHP_PFSOC_SYSREG(dev);
79 
80     memory_region_init_io(&s->sysreg, OBJECT(dev),
81                           &mchp_pfsoc_sysreg_ops, s,
82                           "mchp.pfsoc.sysreg",
83                           MCHP_PFSOC_SYSREG_REG_SIZE);
84     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->sysreg);
85     sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq);
86 }
87 
88 static void mchp_pfsoc_sysreg_class_init(ObjectClass *klass, void *data)
89 {
90     DeviceClass *dc = DEVICE_CLASS(klass);
91 
92     dc->desc = "Microchip PolarFire SoC SYSREG module";
93     dc->realize = mchp_pfsoc_sysreg_realize;
94 }
95 
96 static const TypeInfo mchp_pfsoc_sysreg_info = {
97     .name          = TYPE_MCHP_PFSOC_SYSREG,
98     .parent        = TYPE_SYS_BUS_DEVICE,
99     .instance_size = sizeof(MchpPfSoCSysregState),
100     .class_init    = mchp_pfsoc_sysreg_class_init,
101 };
102 
103 static void mchp_pfsoc_sysreg_register_types(void)
104 {
105     type_register_static(&mchp_pfsoc_sysreg_info);
106 }
107 
108 type_init(mchp_pfsoc_sysreg_register_types)
109