xref: /openbmc/qemu/hw/misc/arm_integrator_debug.c (revision f4ceebde)
1 /*
2  * LED, Switch and Debug control registers for ARM Integrator Boards
3  *
4  * This is currently a stub for this functionality but at least
5  * ensures something other than unassigned_mem_read() handles access
6  * to this area.
7  *
8  * The real h/w is described at:
9  *  https://developer.arm.com/documentation/dui0159/b/peripherals-and-interfaces/debug-leds-and-dip-switch-interface
10  *
11  * Copyright (c) 2013 Alex Bennée <alex@bennee.com>
12  *
13  * This work is licensed under the terms of the GNU GPL, version 2 or later.
14  * See the COPYING file in the top-level directory.
15  */
16 
17 #include "qemu/osdep.h"
18 #include "hw/sysbus.h"
19 #include "hw/misc/arm_integrator_debug.h"
20 #include "qemu/log.h"
21 #include "qemu/module.h"
22 #include "qom/object.h"
23 
24 OBJECT_DECLARE_SIMPLE_TYPE(IntegratorDebugState, INTEGRATOR_DEBUG)
25 
26 struct IntegratorDebugState {
27     SysBusDevice parent_obj;
28 
29     MemoryRegion iomem;
30 };
31 
intdbg_control_read(void * opaque,hwaddr offset,unsigned size)32 static uint64_t intdbg_control_read(void *opaque, hwaddr offset,
33                                     unsigned size)
34 {
35     switch (offset >> 2) {
36     case 0: /* ALPHA */
37     case 1: /* LEDS */
38     case 2: /* SWITCHES */
39         qemu_log_mask(LOG_UNIMP,
40                       "%s: returning zero from %" HWADDR_PRIx ":%u\n",
41                       __func__, offset, size);
42         return 0;
43     default:
44         qemu_log_mask(LOG_GUEST_ERROR,
45                       "%s: Bad offset %" HWADDR_PRIx,
46                       __func__, offset);
47         return 0;
48     }
49 }
50 
intdbg_control_write(void * opaque,hwaddr offset,uint64_t value,unsigned size)51 static void intdbg_control_write(void *opaque, hwaddr offset,
52                                  uint64_t value, unsigned size)
53 {
54     switch (offset >> 2) {
55     case 1: /* ALPHA */
56     case 2: /* LEDS */
57     case 3: /* SWITCHES */
58         /* Nothing interesting implemented yet.  */
59         qemu_log_mask(LOG_UNIMP,
60                       "%s: ignoring write of %" PRIu64
61                       " to %" HWADDR_PRIx ":%u\n",
62                       __func__, value, offset, size);
63         break;
64     default:
65         qemu_log_mask(LOG_GUEST_ERROR,
66                       "%s: write of %" PRIu64
67                       " to bad offset %" HWADDR_PRIx "\n",
68                       __func__, value, offset);
69     }
70 }
71 
72 static const MemoryRegionOps intdbg_control_ops = {
73     .read = intdbg_control_read,
74     .write = intdbg_control_write,
75     .endianness = DEVICE_NATIVE_ENDIAN,
76 };
77 
intdbg_control_init(Object * obj)78 static void intdbg_control_init(Object *obj)
79 {
80     SysBusDevice *sd = SYS_BUS_DEVICE(obj);
81     IntegratorDebugState *s = INTEGRATOR_DEBUG(obj);
82 
83     memory_region_init_io(&s->iomem, obj, &intdbg_control_ops,
84                           NULL, "dbg-leds", 0x1000000);
85     sysbus_init_mmio(sd, &s->iomem);
86 }
87 
88 static const TypeInfo intdbg_info = {
89     .name          = TYPE_INTEGRATOR_DEBUG,
90     .parent        = TYPE_SYS_BUS_DEVICE,
91     .instance_size = sizeof(IntegratorDebugState),
92     .instance_init = intdbg_control_init,
93 };
94 
intdbg_register_types(void)95 static void intdbg_register_types(void)
96 {
97     type_register_static(&intdbg_info);
98 }
99 
100 type_init(intdbg_register_types)
101