| 1 | /* |
| 2 | * Device model for Cadence UART |
| 3 | * |
| 4 | * Reference: Xilinx Zynq 7000 reference manual |
| 5 | * - http://www.xilinx.com/support/documentation/user_guides/ug585-Zynq-7000-TRM.pdf |
| 6 | * - Chapter 19 UART Controller |
| 7 | * - Appendix B for Register details |
| 8 | * |
| 9 | * Copyright (c) 2010 Xilinx Inc. |
| 10 | * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com) |
| 11 | * Copyright (c) 2012 PetaLogix Pty Ltd. |
| 12 | * Written by Haibing Ma |
| 13 | * M.Habib |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or |
| 16 | * modify it under the terms of the GNU General Public License |
| 17 | * as published by the Free Software Foundation; either version |
| 18 | * 2 of the License, or (at your option) any later version. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License along |
| 21 | * with this program; if not, see <http://www.gnu.org/licenses/>. |
| 22 | */ |
| 23 | |
| 24 | #include "qemu/osdep.h" |
| 25 | #include "hw/core/sysbus.h" |
| 26 | #include "migration/vmstate.h" |
| 27 | #include "chardev/char-fe.h" |
| 28 | #include "chardev/char-serial.h" |
| 29 | #include "qemu/timer.h" |
| 30 | #include "qemu/log.h" |
| 31 | #include "qemu/module.h" |
| 32 | #include "hw/char/cadence_uart.h" |
| 33 | #include "hw/core/irq.h" |
| 34 | #include "hw/core/qdev-clock.h" |
| 35 | #include "hw/core/qdev-properties-system.h" |
| 36 | #include "trace.h" |
| 37 | |
| 38 | #ifdef CADENCE_UART_ERR_DEBUG |
| 39 | #define DB_PRINT(...) do { \ |
| 40 | fprintf(stderr, ": %s: ", __func__); \ |
| 41 | fprintf(stderr, ## __VA_ARGS__); \ |
| 42 | } while (0) |
| 43 | #else |
| 44 | #define DB_PRINT(...) |
| 45 | #endif |
| 46 | |
| 47 | #define UART_SR_INTR_RTRIG 0x00000001 |
| 48 | #define UART_SR_INTR_REMPTY 0x00000002 |
| 49 | #define UART_SR_INTR_RFUL 0x00000004 |
| 50 | #define UART_SR_INTR_TEMPTY 0x00000008 |
| 51 | #define UART_SR_INTR_TFUL 0x00000010 |
| 52 | /* somewhat awkwardly, TTRIG is misaligned between SR and ISR */ |
| 53 | #define UART_SR_TTRIG 0x00002000 |
| 54 | #define UART_INTR_TTRIG 0x00000400 |
| 55 | /* bits fields in CSR that correlate to CISR. If any of these bits are set in |
| 56 | * SR, then the same bit in CISR is set high too */ |
| 57 | #define UART_SR_TO_CISR_MASK 0x0000001F |
| 58 | |
| 59 | #define UART_INTR_ROVR 0x00000020 |
| 60 | #define UART_INTR_FRAME 0x00000040 |
| 61 | #define UART_INTR_PARE 0x00000080 |
| 62 | #define UART_INTR_TIMEOUT 0x00000100 |
| 63 | #define UART_INTR_DMSI 0x00000200 |
| 64 | #define UART_INTR_TOVR 0x00001000 |
| 65 | |
| 66 | #define UART_SR_RACTIVE 0x00000400 |
| 67 | #define UART_SR_TACTIVE 0x00000800 |
| 68 | #define UART_SR_FDELT 0x00001000 |
| 69 | |
| 70 | #define UART_CR_RXRST 0x00000001 |
| 71 | #define UART_CR_TXRST 0x00000002 |
| 72 | #define UART_CR_RX_EN 0x00000004 |
| 73 | #define UART_CR_RX_DIS 0x00000008 |
| 74 | #define UART_CR_TX_EN 0x00000010 |
| 75 | #define UART_CR_TX_DIS 0x00000020 |
| 76 | #define UART_CR_RST_TO 0x00000040 |
| 77 | #define UART_CR_STARTBRK 0x00000080 |
| 78 | #define UART_CR_STOPBRK 0x00000100 |
| 79 | |
| 80 | #define UART_MR_CLKS 0x00000001 |
| 81 | #define UART_MR_CHRL 0x00000006 |
| 82 | #define UART_MR_CHRL_SH 1 |
| 83 | #define UART_MR_PAR 0x00000038 |
| 84 | #define UART_MR_PAR_SH 3 |
| 85 | #define UART_MR_NBSTOP 0x000000C0 |
| 86 | #define UART_MR_NBSTOP_SH 6 |
| 87 | #define UART_MR_CHMODE 0x00000300 |
| 88 | #define UART_MR_CHMODE_SH 8 |
| 89 | #define UART_MR_UCLKEN 0x00000400 |
| 90 | #define UART_MR_IRMODE 0x00000800 |
| 91 | |
| 92 | #define UART_DATA_BITS_6 (0x3 << UART_MR_CHRL_SH) |
| 93 | #define UART_DATA_BITS_7 (0x2 << UART_MR_CHRL_SH) |
| 94 | #define UART_PARITY_ODD (0x1 << UART_MR_PAR_SH) |
| 95 | #define UART_PARITY_EVEN (0x0 << UART_MR_PAR_SH) |
| 96 | #define UART_STOP_BITS_1 (0x3 << UART_MR_NBSTOP_SH) |
| 97 | #define UART_STOP_BITS_2 (0x2 << UART_MR_NBSTOP_SH) |
| 98 | #define NORMAL_MODE (0x0 << UART_MR_CHMODE_SH) |
| 99 | #define ECHO_MODE (0x1 << UART_MR_CHMODE_SH) |
| 100 | #define LOCAL_LOOPBACK (0x2 << UART_MR_CHMODE_SH) |
| 101 | #define REMOTE_LOOPBACK (0x3 << UART_MR_CHMODE_SH) |
| 102 | |
| 103 | #define UART_DEFAULT_REF_CLK (50 * 1000 * 1000) |
| 104 | |
| 105 | #define R_CR (0x00/4) |
| 106 | #define R_MR (0x04/4) |
| 107 | #define R_IER (0x08/4) |
| 108 | #define R_IDR (0x0C/4) |
| 109 | #define R_IMR (0x10/4) |
| 110 | #define R_CISR (0x14/4) |
| 111 | #define R_BRGR (0x18/4) |
| 112 | #define R_RTOR (0x1C/4) |
| 113 | #define R_RTRIG (0x20/4) |
| 114 | #define R_MCR (0x24/4) |
| 115 | #define R_MSR (0x28/4) |
| 116 | #define R_SR (0x2C/4) |
| 117 | #define R_TX_RX (0x30/4) |
| 118 | #define R_BDIV (0x34/4) |
| 119 | #define R_FDEL (0x38/4) |
| 120 | #define R_PMIN (0x3C/4) |
| 121 | #define R_PWID (0x40/4) |
| 122 | #define R_TTRIG (0x44/4) |
| 123 | |
| 124 | |
| 125 | static void uart_update_status(CadenceUARTState *s) |
| 126 | { |
| 127 | s->r[R_SR] = 0; |
| 128 | |
| 129 | s->r[R_SR] |= s->rx_count == CADENCE_UART_RX_FIFO_SIZE ? UART_SR_INTR_RFUL |
| 130 | : 0; |
| 131 | s->r[R_SR] |= !s->rx_count ? UART_SR_INTR_REMPTY : 0; |
| 132 | s->r[R_SR] |= s->rx_count >= s->r[R_RTRIG] ? UART_SR_INTR_RTRIG : 0; |
| 133 | |
| 134 | s->r[R_SR] |= s->tx_count == CADENCE_UART_TX_FIFO_SIZE ? UART_SR_INTR_TFUL |
| 135 | : 0; |
| 136 | s->r[R_SR] |= !s->tx_count ? UART_SR_INTR_TEMPTY : 0; |
| 137 | s->r[R_SR] |= s->tx_count >= s->r[R_TTRIG] ? UART_SR_TTRIG : 0; |
| 138 | |
| 139 | s->r[R_CISR] |= s->r[R_SR] & UART_SR_TO_CISR_MASK; |
| 140 | s->r[R_CISR] |= s->r[R_SR] & UART_SR_TTRIG ? UART_INTR_TTRIG : 0; |
| 141 | qemu_set_irq(s->irq, !!(s->r[R_IMR] & s->r[R_CISR])); |
| 142 | } |
| 143 | |
| 144 | static void fifo_trigger_update(void *opaque) |
| 145 | { |
| 146 | CadenceUARTState *s = opaque; |
| 147 | |
| 148 | if (s->r[R_RTOR]) { |
| 149 | s->r[R_CISR] |= UART_INTR_TIMEOUT; |
| 150 | uart_update_status(s); |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | static void uart_rx_reset(CadenceUARTState *s) |
| 155 | { |
| 156 | s->rx_wpos = 0; |
| 157 | s->rx_count = 0; |
| 158 | qemu_chr_fe_accept_input(&s->chr); |
| 159 | } |
| 160 | |
| 161 | static void uart_tx_reset(CadenceUARTState *s) |
| 162 | { |
| 163 | s->tx_count = 0; |
| 164 | } |
| 165 | |
| 166 | static void uart_send_breaks(CadenceUARTState *s) |
| 167 | { |
| 168 | int break_enabled = 1; |
| 169 | |
| 170 | qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_BREAK, |
| 171 | &break_enabled); |
| 172 | } |
| 173 | |
| 174 | static void uart_parameters_setup(CadenceUARTState *s) |
| 175 | { |
| 176 | QEMUSerialSetParams ssp; |
| 177 | unsigned int baud_rate, packet_size, input_clk; |
| 178 | input_clk = clock_get_hz(s->refclk); |
| 179 | |
| 180 | baud_rate = (s->r[R_MR] & UART_MR_CLKS) ? input_clk / 8 : input_clk; |
| 181 | baud_rate /= (s->r[R_BRGR] * (s->r[R_BDIV] + 1)); |
| 182 | trace_cadence_uart_baudrate(baud_rate); |
| 183 | |
| 184 | ssp.speed = baud_rate; |
| 185 | |
| 186 | packet_size = 1; |
| 187 | |
| 188 | switch (s->r[R_MR] & UART_MR_PAR) { |
| 189 | case UART_PARITY_EVEN: |
| 190 | ssp.parity = 'E'; |
| 191 | packet_size++; |
| 192 | break; |
| 193 | case UART_PARITY_ODD: |
| 194 | ssp.parity = 'O'; |
| 195 | packet_size++; |
| 196 | break; |
| 197 | default: |
| 198 | ssp.parity = 'N'; |
| 199 | break; |
| 200 | } |
| 201 | |
| 202 | switch (s->r[R_MR] & UART_MR_CHRL) { |
| 203 | case UART_DATA_BITS_6: |
| 204 | ssp.data_bits = 6; |
| 205 | break; |
| 206 | case UART_DATA_BITS_7: |
| 207 | ssp.data_bits = 7; |
| 208 | break; |
| 209 | default: |
| 210 | ssp.data_bits = 8; |
| 211 | break; |
| 212 | } |
| 213 | |
| 214 | switch (s->r[R_MR] & UART_MR_NBSTOP) { |
| 215 | case UART_STOP_BITS_1: |
| 216 | ssp.stop_bits = 1; |
| 217 | break; |
| 218 | default: |
| 219 | ssp.stop_bits = 2; |
| 220 | break; |
| 221 | } |
| 222 | |
| 223 | packet_size += ssp.data_bits + ssp.stop_bits; |
| 224 | if (ssp.speed == 0) { |
| 225 | /* |
| 226 | * Avoid division-by-zero below. |
| 227 | * TODO: find something better |
| 228 | */ |
| 229 | ssp.speed = 1; |
| 230 | } |
| 231 | s->char_tx_time = (NANOSECONDS_PER_SECOND / ssp.speed) * packet_size; |
| 232 | qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp); |
| 233 | } |
| 234 | |
| 235 | static int uart_can_receive(void *opaque) |
| 236 | { |
| 237 | CadenceUARTState *s = opaque; |
| 238 | int ret; |
| 239 | uint32_t ch_mode; |
| 240 | |
| 241 | /* ignore characters when unclocked or in reset */ |
| 242 | if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) { |
| 243 | qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n", |
| 244 | __func__); |
| 245 | return 0; |
| 246 | } |
| 247 | |
| 248 | ret = MAX(CADENCE_UART_RX_FIFO_SIZE, CADENCE_UART_TX_FIFO_SIZE); |
| 249 | ch_mode = s->r[R_MR] & UART_MR_CHMODE; |
| 250 | |
| 251 | if (ch_mode == NORMAL_MODE || ch_mode == ECHO_MODE) { |
| 252 | ret = MIN(ret, CADENCE_UART_RX_FIFO_SIZE - s->rx_count); |
| 253 | } |
| 254 | if (ch_mode == REMOTE_LOOPBACK || ch_mode == ECHO_MODE) { |
| 255 | ret = MIN(ret, CADENCE_UART_TX_FIFO_SIZE - s->tx_count); |
| 256 | } |
| 257 | return ret; |
| 258 | } |
| 259 | |
| 260 | static void uart_ctrl_update(CadenceUARTState *s) |
| 261 | { |
| 262 | if (s->r[R_CR] & UART_CR_TXRST) { |
| 263 | uart_tx_reset(s); |
| 264 | } |
| 265 | |
| 266 | if (s->r[R_CR] & UART_CR_RXRST) { |
| 267 | uart_rx_reset(s); |
| 268 | } |
| 269 | |
| 270 | s->r[R_CR] &= ~(UART_CR_TXRST | UART_CR_RXRST); |
| 271 | |
| 272 | if (s->r[R_CR] & UART_CR_STARTBRK && !(s->r[R_CR] & UART_CR_STOPBRK)) { |
| 273 | uart_send_breaks(s); |
| 274 | } |
| 275 | } |
| 276 | |
| 277 | static void uart_write_rx_fifo(void *opaque, const uint8_t *buf, int size) |
| 278 | { |
| 279 | CadenceUARTState *s = opaque; |
| 280 | uint64_t new_rx_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| 281 | int i; |
| 282 | |
| 283 | if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) { |
| 284 | return; |
| 285 | } |
| 286 | |
| 287 | if (s->rx_count == CADENCE_UART_RX_FIFO_SIZE) { |
| 288 | s->r[R_CISR] |= UART_INTR_ROVR; |
| 289 | } else { |
| 290 | for (i = 0; i < size; i++) { |
| 291 | s->rx_fifo[s->rx_wpos] = buf[i]; |
| 292 | s->rx_wpos = (s->rx_wpos + 1) % CADENCE_UART_RX_FIFO_SIZE; |
| 293 | s->rx_count++; |
| 294 | } |
| 295 | timer_mod(s->fifo_trigger_handle, new_rx_time + |
| 296 | (s->char_tx_time * 4)); |
| 297 | } |
| 298 | uart_update_status(s); |
| 299 | } |
| 300 | |
| 301 | static gboolean cadence_uart_xmit(void *do_not_use, GIOCondition cond, |
| 302 | void *opaque) |
| 303 | { |
| 304 | CadenceUARTState *s = opaque; |
| 305 | int ret; |
| 306 | |
| 307 | /* instant drain the fifo when there's no back-end */ |
| 308 | if (!qemu_chr_fe_backend_connected(&s->chr)) { |
| 309 | s->tx_count = 0; |
| 310 | return G_SOURCE_REMOVE; |
| 311 | } |
| 312 | |
| 313 | if (!s->tx_count) { |
| 314 | return G_SOURCE_REMOVE; |
| 315 | } |
| 316 | |
| 317 | ret = qemu_chr_fe_write(&s->chr, s->tx_fifo, s->tx_count); |
| 318 | |
| 319 | if (ret >= 0) { |
| 320 | s->tx_count -= ret; |
| 321 | memmove(s->tx_fifo, s->tx_fifo + ret, s->tx_count); |
| 322 | } |
| 323 | |
| 324 | if (s->tx_count) { |
| 325 | guint r = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP, |
| 326 | cadence_uart_xmit, s); |
| 327 | if (!r) { |
| 328 | s->tx_count = 0; |
| 329 | return G_SOURCE_REMOVE; |
| 330 | } |
| 331 | } |
| 332 | |
| 333 | uart_update_status(s); |
| 334 | return G_SOURCE_REMOVE; |
| 335 | } |
| 336 | |
| 337 | static void uart_write_tx_fifo(CadenceUARTState *s, const uint8_t *buf, |
| 338 | int size) |
| 339 | { |
| 340 | if ((s->r[R_CR] & UART_CR_TX_DIS) || !(s->r[R_CR] & UART_CR_TX_EN)) { |
| 341 | return; |
| 342 | } |
| 343 | |
| 344 | if (size > CADENCE_UART_TX_FIFO_SIZE - s->tx_count) { |
| 345 | size = CADENCE_UART_TX_FIFO_SIZE - s->tx_count; |
| 346 | /* |
| 347 | * This can only be a guest error via a bad tx fifo register push, |
| 348 | * as can_receive() should stop remote loop and echo modes ever getting |
| 349 | * us to here. |
| 350 | */ |
| 351 | qemu_log_mask(LOG_GUEST_ERROR, "cadence_uart: TxFIFO overflow"); |
| 352 | s->r[R_CISR] |= UART_INTR_ROVR; |
| 353 | } |
| 354 | |
| 355 | memcpy(s->tx_fifo + s->tx_count, buf, size); |
| 356 | s->tx_count += size; |
| 357 | |
| 358 | cadence_uart_xmit(NULL, G_IO_OUT, s); |
| 359 | } |
| 360 | |
| 361 | static void uart_receive(void *opaque, const uint8_t *buf, int size) |
| 362 | { |
| 363 | CadenceUARTState *s = opaque; |
| 364 | uint32_t ch_mode = s->r[R_MR] & UART_MR_CHMODE; |
| 365 | |
| 366 | if (ch_mode == NORMAL_MODE || ch_mode == ECHO_MODE) { |
| 367 | uart_write_rx_fifo(opaque, buf, size); |
| 368 | } |
| 369 | if (ch_mode == REMOTE_LOOPBACK || ch_mode == ECHO_MODE) { |
| 370 | uart_write_tx_fifo(s, buf, size); |
| 371 | } |
| 372 | } |
| 373 | |
| 374 | static void uart_event(void *opaque, QEMUChrEvent event) |
| 375 | { |
| 376 | CadenceUARTState *s = opaque; |
| 377 | uint8_t buf = '\0'; |
| 378 | |
| 379 | /* ignore characters when unclocked or in reset */ |
| 380 | if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) { |
| 381 | qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n", |
| 382 | __func__); |
| 383 | return; |
| 384 | } |
| 385 | |
| 386 | if (event == CHR_EVENT_BREAK) { |
| 387 | uart_write_rx_fifo(opaque, &buf, 1); |
| 388 | } |
| 389 | |
| 390 | uart_update_status(s); |
| 391 | } |
| 392 | |
| 393 | static void uart_read_rx_fifo(CadenceUARTState *s, uint32_t *c) |
| 394 | { |
| 395 | if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) { |
| 396 | return; |
| 397 | } |
| 398 | |
| 399 | if (s->rx_count) { |
| 400 | uint32_t rx_rpos = (CADENCE_UART_RX_FIFO_SIZE + s->rx_wpos - |
| 401 | s->rx_count) % CADENCE_UART_RX_FIFO_SIZE; |
| 402 | *c = s->rx_fifo[rx_rpos]; |
| 403 | s->rx_count--; |
| 404 | |
| 405 | qemu_chr_fe_accept_input(&s->chr); |
| 406 | } else { |
| 407 | *c = 0; |
| 408 | } |
| 409 | |
| 410 | uart_update_status(s); |
| 411 | } |
| 412 | |
| 413 | static MemTxResult uart_write(void *opaque, hwaddr offset, |
| 414 | uint64_t value, unsigned size, MemTxAttrs attrs) |
| 415 | { |
| 416 | CadenceUARTState *s = opaque; |
| 417 | |
| 418 | /* ignore access when unclocked or in reset */ |
| 419 | if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) { |
| 420 | qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n", |
| 421 | __func__); |
| 422 | return MEMTX_ERROR; |
| 423 | } |
| 424 | |
| 425 | DB_PRINT(" offset:%x data:%08x\n", (unsigned)offset, (unsigned)value); |
| 426 | offset >>= 2; |
| 427 | if (offset >= CADENCE_UART_R_MAX) { |
| 428 | return MEMTX_DECODE_ERROR; |
| 429 | } |
| 430 | switch (offset) { |
| 431 | case R_IER: /* ier (wts imr) */ |
| 432 | s->r[R_IMR] |= value; |
| 433 | break; |
| 434 | case R_IDR: /* idr (wtc imr) */ |
| 435 | s->r[R_IMR] &= ~value; |
| 436 | break; |
| 437 | case R_IMR: /* imr (read only) */ |
| 438 | break; |
| 439 | case R_CISR: /* cisr (wtc) */ |
| 440 | s->r[R_CISR] &= ~value; |
| 441 | break; |
| 442 | case R_TX_RX: /* UARTDR */ |
| 443 | switch (s->r[R_MR] & UART_MR_CHMODE) { |
| 444 | case NORMAL_MODE: |
| 445 | uart_write_tx_fifo(s, (uint8_t *) &value, 1); |
| 446 | break; |
| 447 | case LOCAL_LOOPBACK: |
| 448 | uart_write_rx_fifo(opaque, (uint8_t *) &value, 1); |
| 449 | break; |
| 450 | } |
| 451 | break; |
| 452 | case R_BRGR: /* Baud rate generator */ |
| 453 | value &= 0xffff; |
| 454 | if (value >= 0x01) { |
| 455 | s->r[offset] = value; |
| 456 | } |
| 457 | break; |
| 458 | case R_BDIV: /* Baud rate divider */ |
| 459 | value &= 0xff; |
| 460 | if (value >= 0x04) { |
| 461 | s->r[offset] = value; |
| 462 | } |
| 463 | break; |
| 464 | default: |
| 465 | s->r[offset] = value; |
| 466 | } |
| 467 | |
| 468 | switch (offset) { |
| 469 | case R_CR: |
| 470 | uart_ctrl_update(s); |
| 471 | break; |
| 472 | case R_MR: |
| 473 | uart_parameters_setup(s); |
| 474 | break; |
| 475 | } |
| 476 | uart_update_status(s); |
| 477 | |
| 478 | return MEMTX_OK; |
| 479 | } |
| 480 | |
| 481 | static MemTxResult uart_read(void *opaque, hwaddr offset, |
| 482 | uint64_t *value, unsigned size, MemTxAttrs attrs) |
| 483 | { |
| 484 | CadenceUARTState *s = opaque; |
| 485 | uint32_t c = 0; |
| 486 | |
| 487 | /* ignore access when unclocked or in reset */ |
| 488 | if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) { |
| 489 | qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n", |
| 490 | __func__); |
| 491 | return MEMTX_ERROR; |
| 492 | } |
| 493 | |
| 494 | offset >>= 2; |
| 495 | if (offset >= CADENCE_UART_R_MAX) { |
| 496 | return MEMTX_DECODE_ERROR; |
| 497 | } |
| 498 | if (offset == R_TX_RX) { |
| 499 | uart_read_rx_fifo(s, &c); |
| 500 | } else { |
| 501 | c = s->r[offset]; |
| 502 | } |
| 503 | |
| 504 | DB_PRINT(" offset:%x data:%08x\n", (unsigned)(offset << 2), (unsigned)c); |
| 505 | *value = c; |
| 506 | return MEMTX_OK; |
| 507 | } |
| 508 | |
| 509 | static const MemoryRegionOps uart_ops = { |
| 510 | .read_with_attrs = uart_read, |
| 511 | .write_with_attrs = uart_write, |
| 512 | .endianness = DEVICE_NATIVE_ENDIAN, |
| 513 | }; |
| 514 | |
| 515 | static void cadence_uart_reset_init(Object *obj, ResetType type) |
| 516 | { |
| 517 | CadenceUARTState *s = CADENCE_UART(obj); |
| 518 | |
| 519 | s->r[R_CR] = 0x00000128; |
| 520 | s->r[R_IMR] = 0; |
| 521 | s->r[R_CISR] = 0; |
| 522 | s->r[R_RTRIG] = 0x00000020; |
| 523 | s->r[R_BRGR] = 0x0000028B; |
| 524 | s->r[R_BDIV] = 0x0000000F; |
| 525 | s->r[R_TTRIG] = 0x00000020; |
| 526 | } |
| 527 | |
| 528 | static void cadence_uart_reset_hold(Object *obj, ResetType type) |
| 529 | { |
| 530 | CadenceUARTState *s = CADENCE_UART(obj); |
| 531 | |
| 532 | uart_rx_reset(s); |
| 533 | uart_tx_reset(s); |
| 534 | |
| 535 | uart_update_status(s); |
| 536 | } |
| 537 | |
| 538 | static void cadence_uart_realize(DeviceState *dev, Error **errp) |
| 539 | { |
| 540 | CadenceUARTState *s = CADENCE_UART(dev); |
| 541 | |
| 542 | s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL, |
| 543 | fifo_trigger_update, s); |
| 544 | |
| 545 | qemu_chr_fe_set_handlers(&s->chr, uart_can_receive, uart_receive, |
| 546 | uart_event, NULL, s, NULL, true); |
| 547 | } |
| 548 | |
| 549 | static void cadence_uart_refclk_update(void *opaque, ClockEvent event) |
| 550 | { |
| 551 | CadenceUARTState *s = opaque; |
| 552 | |
| 553 | /* recompute uart's speed on clock change */ |
| 554 | uart_parameters_setup(s); |
| 555 | } |
| 556 | |
| 557 | static void cadence_uart_init(Object *obj) |
| 558 | { |
| 559 | SysBusDevice *sbd = SYS_BUS_DEVICE(obj); |
| 560 | CadenceUARTState *s = CADENCE_UART(obj); |
| 561 | |
| 562 | memory_region_init_io(&s->iomem, obj, &uart_ops, s, "uart", 0x1000); |
| 563 | sysbus_init_mmio(sbd, &s->iomem); |
| 564 | sysbus_init_irq(sbd, &s->irq); |
| 565 | |
| 566 | s->refclk = qdev_init_clock_in(DEVICE(obj), "refclk", |
| 567 | cadence_uart_refclk_update, s, ClockUpdate); |
| 568 | /* initialize the frequency in case the clock remains unconnected */ |
| 569 | clock_set_hz(s->refclk, UART_DEFAULT_REF_CLK); |
| 570 | |
| 571 | s->char_tx_time = (NANOSECONDS_PER_SECOND / 9600) * 10; |
| 572 | } |
| 573 | |
| 574 | static int cadence_uart_pre_load(void *opaque) |
| 575 | { |
| 576 | CadenceUARTState *s = opaque; |
| 577 | |
| 578 | /* the frequency will be overridden if the refclk field is present */ |
| 579 | clock_set_hz(s->refclk, UART_DEFAULT_REF_CLK); |
| 580 | return 0; |
| 581 | } |
| 582 | |
| 583 | static int cadence_uart_post_load(void *opaque, int version_id) |
| 584 | { |
| 585 | CadenceUARTState *s = opaque; |
| 586 | |
| 587 | /* Ensure these two aren't invalid numbers */ |
| 588 | if (s->r[R_BRGR] < 1 || s->r[R_BRGR] & ~0xFFFF || |
| 589 | s->r[R_BDIV] <= 3 || s->r[R_BDIV] & ~0xFF) { |
| 590 | /* Value is invalid, abort */ |
| 591 | return 1; |
| 592 | } |
| 593 | |
| 594 | uart_parameters_setup(s); |
| 595 | uart_update_status(s); |
| 596 | return 0; |
| 597 | } |
| 598 | |
| 599 | static const VMStateDescription vmstate_cadence_uart = { |
| 600 | .name = "cadence_uart", |
| 601 | .version_id = 3, |
| 602 | .minimum_version_id = 2, |
| 603 | .pre_load = cadence_uart_pre_load, |
| 604 | .post_load = cadence_uart_post_load, |
| 605 | .fields = (const VMStateField[]) { |
| 606 | VMSTATE_UINT32_ARRAY(r, CadenceUARTState, CADENCE_UART_R_MAX), |
| 607 | VMSTATE_UINT8_ARRAY(rx_fifo, CadenceUARTState, |
| 608 | CADENCE_UART_RX_FIFO_SIZE), |
| 609 | VMSTATE_UINT8_ARRAY(tx_fifo, CadenceUARTState, |
| 610 | CADENCE_UART_TX_FIFO_SIZE), |
| 611 | VMSTATE_UINT32(rx_count, CadenceUARTState), |
| 612 | VMSTATE_UINT32(tx_count, CadenceUARTState), |
| 613 | VMSTATE_UINT32(rx_wpos, CadenceUARTState), |
| 614 | VMSTATE_TIMER_PTR(fifo_trigger_handle, CadenceUARTState), |
| 615 | VMSTATE_CLOCK_V(refclk, CadenceUARTState, 3), |
| 616 | VMSTATE_END_OF_LIST() |
| 617 | }, |
| 618 | }; |
| 619 | |
| 620 | static const Property cadence_uart_properties[] = { |
| 621 | DEFINE_PROP_CHR("chardev", CadenceUARTState, chr), |
| 622 | }; |
| 623 | |
| 624 | static void cadence_uart_class_init(ObjectClass *klass, const void *data) |
| 625 | { |
| 626 | DeviceClass *dc = DEVICE_CLASS(klass); |
| 627 | ResettableClass *rc = RESETTABLE_CLASS(klass); |
| 628 | |
| 629 | dc->realize = cadence_uart_realize; |
| 630 | dc->vmsd = &vmstate_cadence_uart; |
| 631 | rc->phases.enter = cadence_uart_reset_init; |
| 632 | rc->phases.hold = cadence_uart_reset_hold; |
| 633 | device_class_set_props(dc, cadence_uart_properties); |
| 634 | } |
| 635 | |
| 636 | static const TypeInfo cadence_uart_info = { |
| 637 | .name = TYPE_CADENCE_UART, |
| 638 | .parent = TYPE_SYS_BUS_DEVICE, |
| 639 | .instance_size = sizeof(CadenceUARTState), |
| 640 | .instance_init = cadence_uart_init, |
| 641 | .class_init = cadence_uart_class_init, |
| 642 | }; |
| 643 | |
| 644 | static void cadence_uart_register_types(void) |
| 645 | { |
| 646 | type_register_static(&cadence_uart_info); |
| 647 | } |
| 648 | |
| 649 | type_init(cadence_uart_register_types) |