]>
Commit | Line | Data |
---|---|---|
8b1e1320 FC |
1 | /* |
2 | * QEMU GRLIB APB UART Emulator | |
3 | * | |
4 | * Copyright (c) 2010-2011 AdaCore | |
5 | * | |
6 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
7 | * of this software and associated documentation files (the "Software"), to deal | |
8 | * in the Software without restriction, including without limitation the rights | |
9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
10 | * copies of the Software, and to permit persons to whom the Software is | |
11 | * furnished to do so, subject to the following conditions: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
22 | * THE SOFTWARE. | |
23 | */ | |
24 | ||
25 | #include "sysbus.h" | |
26 | #include "qemu-char.h" | |
27 | ||
28 | #include "trace.h" | |
29 | ||
30 | #define UART_REG_SIZE 20 /* Size of memory mapped registers */ | |
31 | ||
32 | /* UART status register fields */ | |
33 | #define UART_DATA_READY (1 << 0) | |
34 | #define UART_TRANSMIT_SHIFT_EMPTY (1 << 1) | |
35 | #define UART_TRANSMIT_FIFO_EMPTY (1 << 2) | |
36 | #define UART_BREAK_RECEIVED (1 << 3) | |
37 | #define UART_OVERRUN (1 << 4) | |
38 | #define UART_PARITY_ERROR (1 << 5) | |
39 | #define UART_FRAMING_ERROR (1 << 6) | |
40 | #define UART_TRANSMIT_FIFO_HALF (1 << 7) | |
41 | #define UART_RECEIVE_FIFO_HALF (1 << 8) | |
42 | #define UART_TRANSMIT_FIFO_FULL (1 << 9) | |
43 | #define UART_RECEIVE_FIFO_FULL (1 << 10) | |
44 | ||
45 | /* UART control register fields */ | |
46 | #define UART_RECEIVE_ENABLE (1 << 0) | |
47 | #define UART_TRANSMIT_ENABLE (1 << 1) | |
48 | #define UART_RECEIVE_INTERRUPT (1 << 2) | |
49 | #define UART_TRANSMIT_INTERRUPT (1 << 3) | |
50 | #define UART_PARITY_SELECT (1 << 4) | |
51 | #define UART_PARITY_ENABLE (1 << 5) | |
52 | #define UART_FLOW_CONTROL (1 << 6) | |
53 | #define UART_LOOPBACK (1 << 7) | |
54 | #define UART_EXTERNAL_CLOCK (1 << 8) | |
55 | #define UART_RECEIVE_FIFO_INTERRUPT (1 << 9) | |
56 | #define UART_TRANSMIT_FIFO_INTERRUPT (1 << 10) | |
57 | #define UART_FIFO_DEBUG_MODE (1 << 11) | |
58 | #define UART_OUTPUT_ENABLE (1 << 12) | |
59 | #define UART_FIFO_AVAILABLE (1 << 31) | |
60 | ||
61 | /* Memory mapped register offsets */ | |
62 | #define DATA_OFFSET 0x00 | |
63 | #define STATUS_OFFSET 0x04 | |
64 | #define CONTROL_OFFSET 0x08 | |
65 | #define SCALER_OFFSET 0x0C /* not supported */ | |
66 | #define FIFO_DEBUG_OFFSET 0x10 /* not supported */ | |
67 | ||
0c685d28 FC |
68 | #define FIFO_LENGTH 1024 |
69 | ||
8b1e1320 FC |
70 | typedef struct UART { |
71 | SysBusDevice busdev; | |
6281f7d1 | 72 | MemoryRegion iomem; |
8b1e1320 FC |
73 | qemu_irq irq; |
74 | ||
75 | CharDriverState *chr; | |
76 | ||
77 | /* registers */ | |
78 | uint32_t receive; | |
79 | uint32_t status; | |
80 | uint32_t control; | |
0c685d28 FC |
81 | |
82 | /* FIFO */ | |
83 | char buffer[FIFO_LENGTH]; | |
84 | int len; | |
85 | int current; | |
8b1e1320 FC |
86 | } UART; |
87 | ||
0c685d28 FC |
88 | static int uart_data_to_read(UART *uart) |
89 | { | |
90 | return uart->current < uart->len; | |
91 | } | |
92 | ||
93 | static char uart_pop(UART *uart) | |
94 | { | |
95 | char ret; | |
96 | ||
97 | if (uart->len == 0) { | |
98 | uart->status &= ~UART_DATA_READY; | |
99 | return 0; | |
100 | } | |
101 | ||
102 | ret = uart->buffer[uart->current++]; | |
103 | ||
104 | if (uart->current >= uart->len) { | |
105 | /* Flush */ | |
106 | uart->len = 0; | |
107 | uart->current = 0; | |
108 | } | |
109 | ||
110 | if (!uart_data_to_read(uart)) { | |
111 | uart->status &= ~UART_DATA_READY; | |
112 | } | |
113 | ||
114 | return ret; | |
115 | } | |
116 | ||
117 | static void uart_add_to_fifo(UART *uart, | |
118 | const uint8_t *buffer, | |
119 | int length) | |
120 | { | |
121 | if (uart->len + length > FIFO_LENGTH) { | |
122 | abort(); | |
123 | } | |
124 | memcpy(uart->buffer + uart->len, buffer, length); | |
125 | uart->len += length; | |
126 | } | |
127 | ||
8b1e1320 FC |
128 | static int grlib_apbuart_can_receive(void *opaque) |
129 | { | |
130 | UART *uart = opaque; | |
131 | ||
0c685d28 | 132 | return FIFO_LENGTH - uart->len; |
8b1e1320 FC |
133 | } |
134 | ||
135 | static void grlib_apbuart_receive(void *opaque, const uint8_t *buf, int size) | |
136 | { | |
137 | UART *uart = opaque; | |
138 | ||
0c685d28 FC |
139 | uart_add_to_fifo(uart, buf, size); |
140 | ||
141 | uart->status |= UART_DATA_READY; | |
8b1e1320 FC |
142 | |
143 | if (uart->control & UART_RECEIVE_INTERRUPT) { | |
144 | qemu_irq_pulse(uart->irq); | |
145 | } | |
146 | } | |
147 | ||
148 | static void grlib_apbuart_event(void *opaque, int event) | |
149 | { | |
150 | trace_grlib_apbuart_event(event); | |
151 | } | |
152 | ||
0c685d28 FC |
153 | |
154 | static uint64_t grlib_apbuart_read(void *opaque, target_phys_addr_t addr, | |
155 | unsigned size) | |
156 | { | |
157 | UART *uart = opaque; | |
158 | ||
159 | addr &= 0xff; | |
160 | ||
161 | /* Unit registers */ | |
162 | switch (addr) { | |
163 | case DATA_OFFSET: | |
164 | case DATA_OFFSET + 3: /* when only one byte read */ | |
165 | return uart_pop(uart); | |
166 | ||
167 | case STATUS_OFFSET: | |
168 | /* Read Only */ | |
169 | return uart->status; | |
170 | ||
171 | case CONTROL_OFFSET: | |
172 | return uart->control; | |
173 | ||
174 | case SCALER_OFFSET: | |
175 | /* Not supported */ | |
176 | return 0; | |
177 | ||
178 | default: | |
179 | trace_grlib_apbuart_readl_unknown(addr); | |
180 | return 0; | |
181 | } | |
182 | } | |
183 | ||
184 | static void grlib_apbuart_write(void *opaque, target_phys_addr_t addr, | |
185 | uint64_t value, unsigned size) | |
8b1e1320 FC |
186 | { |
187 | UART *uart = opaque; | |
188 | unsigned char c = 0; | |
189 | ||
190 | addr &= 0xff; | |
191 | ||
192 | /* Unit registers */ | |
193 | switch (addr) { | |
194 | case DATA_OFFSET: | |
0c685d28 | 195 | case DATA_OFFSET + 3: /* When only one byte write */ |
8b1e1320 | 196 | c = value & 0xFF; |
2cc6e0a1 | 197 | qemu_chr_fe_write(uart->chr, &c, 1); |
8b1e1320 FC |
198 | return; |
199 | ||
200 | case STATUS_OFFSET: | |
201 | /* Read Only */ | |
202 | return; | |
203 | ||
204 | case CONTROL_OFFSET: | |
0c685d28 | 205 | uart->control = value; |
8b1e1320 FC |
206 | return; |
207 | ||
208 | case SCALER_OFFSET: | |
209 | /* Not supported */ | |
210 | return; | |
211 | ||
212 | default: | |
213 | break; | |
214 | } | |
215 | ||
b4548fcc | 216 | trace_grlib_apbuart_writel_unknown(addr, value); |
8b1e1320 FC |
217 | } |
218 | ||
6281f7d1 | 219 | static const MemoryRegionOps grlib_apbuart_ops = { |
0c685d28 FC |
220 | .write = grlib_apbuart_write, |
221 | .read = grlib_apbuart_read, | |
6281f7d1 | 222 | .endianness = DEVICE_NATIVE_ENDIAN, |
8b1e1320 FC |
223 | }; |
224 | ||
225 | static int grlib_apbuart_init(SysBusDevice *dev) | |
226 | { | |
0c685d28 | 227 | UART *uart = FROM_SYSBUS(typeof(*uart), dev); |
8b1e1320 FC |
228 | |
229 | qemu_chr_add_handlers(uart->chr, | |
230 | grlib_apbuart_can_receive, | |
231 | grlib_apbuart_receive, | |
232 | grlib_apbuart_event, | |
233 | uart); | |
234 | ||
235 | sysbus_init_irq(dev, &uart->irq); | |
236 | ||
6281f7d1 AK |
237 | memory_region_init_io(&uart->iomem, &grlib_apbuart_ops, uart, |
238 | "uart", UART_REG_SIZE); | |
8b1e1320 | 239 | |
750ecd44 | 240 | sysbus_init_mmio(dev, &uart->iomem); |
8b1e1320 FC |
241 | |
242 | return 0; | |
243 | } | |
244 | ||
999e12bb AL |
245 | static Property grlib_gptimer_properties[] = { |
246 | DEFINE_PROP_CHR("chrdev", UART, chr), | |
247 | DEFINE_PROP_END_OF_LIST(), | |
248 | }; | |
249 | ||
250 | static void grlib_gptimer_class_init(ObjectClass *klass, void *data) | |
251 | { | |
39bffca2 | 252 | DeviceClass *dc = DEVICE_CLASS(klass); |
999e12bb AL |
253 | SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass); |
254 | ||
255 | k->init = grlib_apbuart_init; | |
39bffca2 | 256 | dc->props = grlib_gptimer_properties; |
999e12bb AL |
257 | } |
258 | ||
39bffca2 AL |
259 | static TypeInfo grlib_gptimer_info = { |
260 | .name = "grlib,apbuart", | |
261 | .parent = TYPE_SYS_BUS_DEVICE, | |
262 | .instance_size = sizeof(UART), | |
263 | .class_init = grlib_gptimer_class_init, | |
8b1e1320 FC |
264 | }; |
265 | ||
83f7d43a | 266 | static void grlib_gptimer_register_types(void) |
8b1e1320 | 267 | { |
39bffca2 | 268 | type_register_static(&grlib_gptimer_info); |
8b1e1320 FC |
269 | } |
270 | ||
83f7d43a | 271 | type_init(grlib_gptimer_register_types) |