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25#include "qemu/osdep.h"
26#include "hw/irq.h"
27#include "hw/qdev-properties.h"
28#include "hw/qdev-properties-system.h"
29#include "hw/sysbus.h"
30#include "chardev/char-fe.h"
31#include "qemu/log.h"
32#include "qemu/module.h"
33#include "qom/object.h"
34
35#define D(x)
36
37#define RW_TR_CTRL (0x00 / 4)
38#define RW_TR_DMA_EN (0x04 / 4)
39#define RW_REC_CTRL (0x08 / 4)
40#define RW_DOUT (0x1c / 4)
41#define RS_STAT_DIN (0x20 / 4)
42#define R_STAT_DIN (0x24 / 4)
43#define RW_INTR_MASK (0x2c / 4)
44#define RW_ACK_INTR (0x30 / 4)
45#define R_INTR (0x34 / 4)
46#define R_MASKED_INTR (0x38 / 4)
47#define R_MAX (0x3c / 4)
48
49#define STAT_DAV 16
50#define STAT_TR_IDLE 22
51#define STAT_TR_RDY 24
52
53#define TYPE_ETRAX_FS_SERIAL "etraxfs-serial"
54typedef struct ETRAXSerial ETRAXSerial;
55DECLARE_INSTANCE_CHECKER(ETRAXSerial, ETRAX_SERIAL,
56 TYPE_ETRAX_FS_SERIAL)
57
58struct ETRAXSerial {
59 SysBusDevice parent_obj;
60
61 MemoryRegion mmio;
62 CharBackend chr;
63 qemu_irq irq;
64
65 int pending_tx;
66
67 uint8_t rx_fifo[16];
68 unsigned int rx_fifo_pos;
69 unsigned int rx_fifo_len;
70
71
72 uint32_t regs[R_MAX];
73};
74
75static void ser_update_irq(ETRAXSerial *s)
76{
77
78 if (s->rx_fifo_len) {
79 s->regs[R_INTR] |= 8;
80 } else {
81 s->regs[R_INTR] &= ~8;
82 }
83
84 s->regs[R_MASKED_INTR] = s->regs[R_INTR] & s->regs[RW_INTR_MASK];
85 qemu_set_irq(s->irq, !!s->regs[R_MASKED_INTR]);
86}
87
88static uint64_t
89ser_read(void *opaque, hwaddr addr, unsigned int size)
90{
91 ETRAXSerial *s = opaque;
92 uint32_t r = 0;
93
94 addr >>= 2;
95 switch (addr)
96 {
97 case R_STAT_DIN:
98 r = s->rx_fifo[(s->rx_fifo_pos - s->rx_fifo_len) & 15];
99 if (s->rx_fifo_len) {
100 r |= 1 << STAT_DAV;
101 }
102 r |= 1 << STAT_TR_RDY;
103 r |= 1 << STAT_TR_IDLE;
104 break;
105 case RS_STAT_DIN:
106 r = s->rx_fifo[(s->rx_fifo_pos - s->rx_fifo_len) & 15];
107 if (s->rx_fifo_len) {
108 r |= 1 << STAT_DAV;
109 s->rx_fifo_len--;
110 }
111 r |= 1 << STAT_TR_RDY;
112 r |= 1 << STAT_TR_IDLE;
113 break;
114 default:
115 r = s->regs[addr];
116 D(qemu_log("%s " TARGET_FMT_plx "=%x\n", __func__, addr, r));
117 break;
118 }
119 return r;
120}
121
122static void
123ser_write(void *opaque, hwaddr addr,
124 uint64_t val64, unsigned int size)
125{
126 ETRAXSerial *s = opaque;
127 uint32_t value = val64;
128 unsigned char ch = val64;
129
130 D(qemu_log("%s " TARGET_FMT_plx "=%x\n", __func__, addr, value));
131 addr >>= 2;
132 switch (addr)
133 {
134 case RW_DOUT:
135
136
137 qemu_chr_fe_write_all(&s->chr, &ch, 1);
138 s->regs[R_INTR] |= 3;
139 s->pending_tx = 1;
140 s->regs[addr] = value;
141 break;
142 case RW_ACK_INTR:
143 if (s->pending_tx) {
144 value &= ~1;
145 s->pending_tx = 0;
146 D(qemu_log("fixedup value=%x r_intr=%x\n",
147 value, s->regs[R_INTR]));
148 }
149 s->regs[addr] = value;
150 s->regs[R_INTR] &= ~value;
151 D(printf("r_intr=%x\n", s->regs[R_INTR]));
152 break;
153 default:
154 s->regs[addr] = value;
155 break;
156 }
157 ser_update_irq(s);
158}
159
160static const MemoryRegionOps ser_ops = {
161 .read = ser_read,
162 .write = ser_write,
163 .endianness = DEVICE_NATIVE_ENDIAN,
164 .valid = {
165 .min_access_size = 4,
166 .max_access_size = 4
167 }
168};
169
170static Property etraxfs_ser_properties[] = {
171 DEFINE_PROP_CHR("chardev", ETRAXSerial, chr),
172 DEFINE_PROP_END_OF_LIST(),
173};
174
175static void serial_receive(void *opaque, const uint8_t *buf, int size)
176{
177 ETRAXSerial *s = opaque;
178 int i;
179
180
181 if (s->rx_fifo_len >= 16) {
182 D(qemu_log("WARNING: UART dropped char.\n"));
183 return;
184 }
185
186 for (i = 0; i < size; i++) {
187 s->rx_fifo[s->rx_fifo_pos] = buf[i];
188 s->rx_fifo_pos++;
189 s->rx_fifo_pos &= 15;
190 s->rx_fifo_len++;
191 }
192
193 ser_update_irq(s);
194}
195
196static int serial_can_receive(void *opaque)
197{
198 ETRAXSerial *s = opaque;
199
200
201 if (!(s->regs[RW_REC_CTRL] & (1 << 3))) {
202 return 0;
203 }
204
205 return sizeof(s->rx_fifo) - s->rx_fifo_len;
206}
207
208static void serial_event(void *opaque, QEMUChrEvent event)
209{
210
211}
212
213static void etraxfs_ser_reset(DeviceState *d)
214{
215 ETRAXSerial *s = ETRAX_SERIAL(d);
216
217
218 s->regs[RS_STAT_DIN] |= (1 << STAT_TR_RDY);
219 s->regs[RS_STAT_DIN] |= (1 << STAT_TR_IDLE);
220
221 s->regs[RW_REC_CTRL] = 0x10000;
222
223}
224
225static void etraxfs_ser_init(Object *obj)
226{
227 ETRAXSerial *s = ETRAX_SERIAL(obj);
228 SysBusDevice *dev = SYS_BUS_DEVICE(obj);
229
230 sysbus_init_irq(dev, &s->irq);
231 memory_region_init_io(&s->mmio, obj, &ser_ops, s,
232 "etraxfs-serial", R_MAX * 4);
233 sysbus_init_mmio(dev, &s->mmio);
234}
235
236static void etraxfs_ser_realize(DeviceState *dev, Error **errp)
237{
238 ETRAXSerial *s = ETRAX_SERIAL(dev);
239
240 qemu_chr_fe_set_handlers(&s->chr,
241 serial_can_receive, serial_receive,
242 serial_event, NULL, s, NULL, true);
243}
244
245static void etraxfs_ser_class_init(ObjectClass *klass, void *data)
246{
247 DeviceClass *dc = DEVICE_CLASS(klass);
248
249 dc->reset = etraxfs_ser_reset;
250 device_class_set_props(dc, etraxfs_ser_properties);
251 dc->realize = etraxfs_ser_realize;
252}
253
254static const TypeInfo etraxfs_ser_info = {
255 .name = TYPE_ETRAX_FS_SERIAL,
256 .parent = TYPE_SYS_BUS_DEVICE,
257 .instance_size = sizeof(ETRAXSerial),
258 .instance_init = etraxfs_ser_init,
259 .class_init = etraxfs_ser_class_init,
260};
261
262static void etraxfs_serial_register_types(void)
263{
264 type_register_static(&etraxfs_ser_info);
265}
266
267type_init(etraxfs_serial_register_types)
268
