drivers/serial/bfin_5xx.c

   1 /*
   2  * File:         drivers/serial/bfin_5xx.c
   3  * Based on:     Based on drivers/serial/sa1100.c
   4  * Author:       Aubrey Li <aubrey.li@analog.com>
   5  *
   6  * Created:
   7  * Description:  Driver for blackfin 5xx serial ports
   8  *
   9  * Modified:
  10  *               Copyright 2006 Analog Devices Inc.
  11  *
  12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, see the file COPYING, or write
  26  * to the Free Software Foundation, Inc.,
  27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  28  */
  29
  30 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  31 #define SUPPORT_SYSRQ
  32 #endif
  33
  34 #include <linux/module.h>
  35 #include <linux/ioport.h>
  36 #include <linux/init.h>
  37 #include <linux/console.h>
  38 #include <linux/sysrq.h>
  39 #include <linux/platform_device.h>
  40 #include <linux/tty.h>
  41 #include <linux/tty_flip.h>
  42 #include <linux/serial_core.h>
  43
  44 #ifdef CONFIG_KGDB_UART
  45 #include <linux/kgdb.h>
  46 #include <asm/irq_regs.h>
  47 #endif
  48
  49 #include <asm/gpio.h>
  50 #include <asm/mach/bfin_serial_5xx.h>
  51
  52 #ifdef CONFIG_SERIAL_BFIN_DMA
  53 #include <linux/dma-mapping.h>
  54 #include <asm/io.h>
  55 #include <asm/irq.h>
  56 #include <asm/cacheflush.h>
  57 #endif
  58
  59 /* UART name and device definitions */
  60 #define BFIN_SERIAL_NAME        "ttyBF"
  61 #define BFIN_SERIAL_MAJOR       204
  62 #define BFIN_SERIAL_MINOR       64
  63
  64 /*
  65  * Setup for console. Argument comes from the menuconfig
  66  */
  67 #define DMA_RX_XCOUNT           512
  68 #define DMA_RX_YCOUNT           (PAGE_SIZE / DMA_RX_XCOUNT)
  69
  70 #define DMA_RX_FLUSH_JIFFIES    5
  71
  72 #ifdef CONFIG_SERIAL_BFIN_DMA
  73 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
  74 #else
  75 static void bfin_serial_do_work(struct work_struct *work);
  76 static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
  77 static void local_put_char(struct bfin_serial_port *uart, char ch);
  78 #endif
  79
  80 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
  81
  82 /*
  83  * interrupts are disabled on entry
  84  */
  85 static void bfin_serial_stop_tx(struct uart_port *port)
  86 {
  87         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
  88
  89 #ifdef CONFIG_SERIAL_BFIN_DMA
  90         disable_dma(uart->tx_dma_channel);
  91 #else
  92         unsigned short ier;
  93
  94         ier = UART_GET_IER(uart);
  95         ier &= ~ETBEI;
  96         UART_PUT_IER(uart, ier);
  97 #endif
  98 }
  99
 100 /*
 101  * port is locked and interrupts are disabled
 102  */
 103 static void bfin_serial_start_tx(struct uart_port *port)
 104 {
 105         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 106
 107 #ifdef CONFIG_SERIAL_BFIN_DMA
 108         bfin_serial_dma_tx_chars(uart);
 109 #else
 110         unsigned short ier;
 111         ier = UART_GET_IER(uart);
 112         ier |= ETBEI;
 113         UART_PUT_IER(uart, ier);
 114         bfin_serial_tx_chars(uart);
 115 #endif
 116 }
 117
 118 /*
 119  * Interrupts are enabled
 120  */
 121 static void bfin_serial_stop_rx(struct uart_port *port)
 122 {
 123         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 124         unsigned short ier;
 125
 126         ier = UART_GET_IER(uart);
 127 #ifdef  CONFIG_KGDB_UART
 128         if (uart->port.line != CONFIG_KGDB_UART_PORT)
 129 #endif
 130         ier &= ~ERBFI;
 131         UART_PUT_IER(uart, ier);
 132 }
 133
 134 /*
 135  * Set the modem control timer to fire immediately.
 136  */
 137 static void bfin_serial_enable_ms(struct uart_port *port)
 138 {
 139 }
 140
 141 #ifdef CONFIG_KGDB_UART
 142 static int kgdb_entry_state;
 143
 144 void kgdb_put_debug_char(int chr)
 145 {
 146         struct bfin_serial_port *uart;
 147
 148         if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
 149                 uart = &bfin_serial_ports[0];
 150         else
 151                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
 152
 153         while (!(UART_GET_LSR(uart) & THRE)) {
 154                 __builtin_bfin_ssync();
 155         }
 156         UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
 157         __builtin_bfin_ssync();
 158         UART_PUT_CHAR(uart, (unsigned char)chr);
 159         __builtin_bfin_ssync();
 160 }
 161
 162 int kgdb_get_debug_char(void)
 163 {
 164         struct bfin_serial_port *uart;
 165         unsigned char chr;
 166
 167         if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
 168                 uart = &bfin_serial_ports[0];
 169         else
 170                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
 171
 172         while(!(UART_GET_LSR(uart) & DR)) {
 173                 __builtin_bfin_ssync();
 174         }
 175         UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
 176         __builtin_bfin_ssync();
 177         chr = UART_GET_CHAR(uart);
 178         __builtin_bfin_ssync();
 179
 180         return chr;
 181 }
 182 #endif
 183
 184 #ifdef CONFIG_SERIAL_BFIN_PIO
 185 static void local_put_char(struct bfin_serial_port *uart, char ch)
 186 {
 187         unsigned short status;
 188         int flags = 0;
 189
 190         spin_lock_irqsave(&uart->port.lock, flags);
 191
 192         do {
 193                 status = UART_GET_LSR(uart);
 194         } while (!(status & THRE));
 195
 196         UART_PUT_CHAR(uart, ch);
 197         SSYNC();
 198
 199         spin_unlock_irqrestore(&uart->port.lock, flags);
 200 }
 201
 202 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
 203 {
 204         struct tty_struct *tty = uart->port.info->tty;
 205         unsigned int status, ch, flg;
 206 #ifdef CONFIG_KGDB_UART
 207         struct pt_regs *regs = get_irq_regs();
 208 #endif
 209 #ifdef BF533_FAMILY
 210         static int in_break = 0;
 211 #endif
 212
 213         status = UART_GET_LSR(uart);
 214         ch = UART_GET_CHAR(uart);
 215         uart->port.icount.rx++;
 216
 217 #ifdef CONFIG_KGDB_UART
 218         if (uart->port.line == CONFIG_KGDB_UART_PORT) {
 219                 if (uart->port.cons->index == CONFIG_KGDB_UART_PORT && ch == 0x1) { /* Ctrl + A */
 220                         kgdb_breakkey_pressed(regs);
 221                         return;
 222                 } else if (kgdb_entry_state == 0 && ch == '$') {/* connection from KGDB */
 223                         kgdb_entry_state = 1;
 224                 } else if (kgdb_entry_state == 1 && ch == 'q') {
 225                         kgdb_entry_state = 0;
 226                         kgdb_breakkey_pressed(regs);
 227                         return;
 228                 } else if (ch == 0x3) {/* Ctrl + C */
 229                         kgdb_entry_state = 0;
 230                         kgdb_breakkey_pressed(regs);
 231                         return;
 232                 } else {
 233                         kgdb_entry_state = 0;
 234                 }
 235         }
 236 #endif
 237
 238 #ifdef BF533_FAMILY
 239         /* The BF533 family of processors have a nice misbehavior where
 240          * they continuously generate characters for a "single" break.
 241          * We have to basically ignore this flood until the "next" valid
 242          * character comes across.  All other Blackfin families operate
 243          * properly though.
 244          */
 245         if (in_break) {
 246                 if (ch != 0) {
 247                         in_break = 0;
 248                         ch = UART_GET_CHAR(uart);
 249                         if (bfin_revid() < 5)
 250                                 return;
 251                 } else
 252                         return;
 253         }
 254 #endif
 255
 256         if (status & BI) {
 257 #ifdef BF533_FAMILY
 258                 in_break = 1;
 259 #endif
 260                 uart->port.icount.brk++;
 261                 if (uart_handle_break(&uart->port))
 262                         goto ignore_char;
 263                 status &= ~(PE | FE);
 264         }
 265         if (status & PE)
 266                 uart->port.icount.parity++;
 267         if (status & OE)
 268                 uart->port.icount.overrun++;
 269         if (status & FE)
 270                 uart->port.icount.frame++;
 271
 272         status &= uart->port.read_status_mask;
 273
 274         if (status & BI)
 275                 flg = TTY_BREAK;
 276         else if (status & PE)
 277                 flg = TTY_PARITY;
 278         else if (status & FE)
 279                 flg = TTY_FRAME;
 280         else
 281                 flg = TTY_NORMAL;
 282
 283         if (uart_handle_sysrq_char(&uart->port, ch))
 284                 goto ignore_char;
 285
 286         uart_insert_char(&uart->port, status, OE, ch, flg);
 287
 288  ignore_char:
 289         tty_flip_buffer_push(tty);
 290 }
 291
 292 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
 293 {
 294         struct circ_buf *xmit = &uart->port.info->xmit;
 295
 296         if (uart->port.x_char) {
 297                 UART_PUT_CHAR(uart, uart->port.x_char);
 298                 uart->port.icount.tx++;
 299                 uart->port.x_char = 0;
 300                 return;
 301         }
 302         /*
 303          * Check the modem control lines before
 304          * transmitting anything.
 305          */
 306         bfin_serial_mctrl_check(uart);
 307
 308         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
 309                 bfin_serial_stop_tx(&uart->port);
 310                 return;
 311         }
 312
 313         local_put_char(uart, xmit->buf[xmit->tail]);
 314         xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 315         uart->port.icount.tx++;
 316
 317         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 318                 uart_write_wakeup(&uart->port);
 319
 320         if (uart_circ_empty(xmit))
 321                 bfin_serial_stop_tx(&uart->port);
 322 }
 323
 324 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
 325 {
 326         struct bfin_serial_port *uart = dev_id;
 327
 328         spin_lock(&uart->port.lock);
 329         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_RX_READY)
 330                 bfin_serial_rx_chars(uart);
 331         spin_unlock(&uart->port.lock);
 332         return IRQ_HANDLED;
 333 }
 334
 335 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
 336 {
 337         struct bfin_serial_port *uart = dev_id;
 338
 339         spin_lock(&uart->port.lock);
 340         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_TX_READY)
 341                 bfin_serial_tx_chars(uart);
 342         spin_unlock(&uart->port.lock);
 343         return IRQ_HANDLED;
 344 }
 345
 346
 347 static void bfin_serial_do_work(struct work_struct *work)
 348 {
 349         struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
 350
 351         bfin_serial_mctrl_check(uart);
 352 }
 353
 354 #endif
 355
 356 #ifdef CONFIG_SERIAL_BFIN_DMA
 357 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
 358 {
 359         struct circ_buf *xmit = &uart->port.info->xmit;
 360         unsigned short ier;
 361         int flags = 0;
 362
 363         if (!uart->tx_done)
 364                 return;
 365
 366         uart->tx_done = 0;
 367
 368         if (uart->port.x_char) {
 369                 UART_PUT_CHAR(uart, uart->port.x_char);
 370                 uart->port.icount.tx++;
 371                 uart->port.x_char = 0;
 372                 uart->tx_done = 1;
 373                 return;
 374         }
 375         /*
 376          * Check the modem control lines before
 377          * transmitting anything.
 378          */
 379         bfin_serial_mctrl_check(uart);
 380
 381         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
 382                 bfin_serial_stop_tx(&uart->port);
 383                 uart->tx_done = 1;
 384                 return;
 385         }
 386
 387         spin_lock_irqsave(&uart->port.lock, flags);
 388         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
 389         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
 390                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
 391         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
 392                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
 393         set_dma_config(uart->tx_dma_channel,
 394                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
 395                         INTR_ON_BUF,
 396                         DIMENSION_LINEAR,
 397                         DATA_SIZE_8));
 398         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
 399         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
 400         set_dma_x_modify(uart->tx_dma_channel, 1);
 401         enable_dma(uart->tx_dma_channel);
 402         ier = UART_GET_IER(uart);
 403         ier |= ETBEI;
 404         UART_PUT_IER(uart, ier);
 405         spin_unlock_irqrestore(&uart->port.lock, flags);
 406 }
 407
 408 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
 409 {
 410         struct tty_struct *tty = uart->port.info->tty;
 411         int i, flg, status;
 412
 413         status = UART_GET_LSR(uart);
 414         uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
 415
 416         if (status & BI) {
 417                 uart->port.icount.brk++;
 418                 if (uart_handle_break(&uart->port))
 419                         goto dma_ignore_char;
 420                 status &= ~(PE | FE);
 421         }
 422         if (status & PE)
 423                 uart->port.icount.parity++;
 424         if (status & OE)
 425                 uart->port.icount.overrun++;
 426         if (status & FE)
 427                 uart->port.icount.frame++;
 428
 429         status &= uart->port.read_status_mask;
 430
 431         if (status & BI)
 432                 flg = TTY_BREAK;
 433         else if (status & PE)
 434                 flg = TTY_PARITY;
 435         else if (status & FE)
 436                 flg = TTY_FRAME;
 437         else
 438                 flg = TTY_NORMAL;
 439
 440         for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) {
 441                 if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
 442                         goto dma_ignore_char;
 443                 uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg);
 444         }
 445
 446  dma_ignore_char:
 447         tty_flip_buffer_push(tty);
 448 }
 449
 450 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
 451 {
 452         int x_pos, pos;
 453         int flags = 0;
 454
 455         bfin_serial_dma_tx_chars(uart);
 456
 457         spin_lock_irqsave(&uart->port.lock, flags);
 458         x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel);
 459         if (x_pos == DMA_RX_XCOUNT)
 460                 x_pos = 0;
 461
 462         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
 463
 464         if (pos>uart->rx_dma_buf.tail) {
 465                 uart->rx_dma_buf.tail = pos;
 466                 bfin_serial_dma_rx_chars(uart);
 467                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
 468         }
 469         spin_unlock_irqrestore(&uart->port.lock, flags);
 470         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
 471         add_timer(&(uart->rx_dma_timer));
 472 }
 473
 474 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
 475 {
 476         struct bfin_serial_port *uart = dev_id;
 477         struct circ_buf *xmit = &uart->port.info->xmit;
 478         unsigned short ier;
 479
 480         spin_lock(&uart->port.lock);
 481         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
 482                 clear_dma_irqstat(uart->tx_dma_channel);
 483                 disable_dma(uart->tx_dma_channel);
 484                 ier = UART_GET_IER(uart);
 485                 ier &= ~ETBEI;
 486                 UART_PUT_IER(uart, ier);
 487                 xmit->tail = (xmit->tail+uart->tx_count) &(UART_XMIT_SIZE -1);
 488                 uart->port.icount.tx+=uart->tx_count;
 489
 490                 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 491                         uart_write_wakeup(&uart->port);
 492
 493                 if (uart_circ_empty(xmit))
 494                         bfin_serial_stop_tx(&uart->port);
 495                 uart->tx_done = 1;
 496         }
 497
 498         spin_unlock(&uart->port.lock);
 499         return IRQ_HANDLED;
 500 }
 501
 502 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
 503 {
 504         struct bfin_serial_port *uart = dev_id;
 505         unsigned short irqstat;
 506
 507         uart->rx_dma_nrows++;
 508         if (uart->rx_dma_nrows == DMA_RX_YCOUNT) {
 509                 uart->rx_dma_nrows = 0;
 510                 uart->rx_dma_buf.tail = DMA_RX_XCOUNT*DMA_RX_YCOUNT;
 511                 bfin_serial_dma_rx_chars(uart);
 512                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail = 0;
 513         }
 514         spin_lock(&uart->port.lock);
 515         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
 516         clear_dma_irqstat(uart->rx_dma_channel);
 517
 518         spin_unlock(&uart->port.lock);
 519         return IRQ_HANDLED;
 520 }
 521 #endif
 522
 523 /*
 524  * Return TIOCSER_TEMT when transmitter is not busy.
 525  */
 526 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
 527 {
 528         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 529         unsigned short lsr;
 530
 531         lsr = UART_GET_LSR(uart);
 532         if (lsr & TEMT)
 533                 return TIOCSER_TEMT;
 534         else
 535                 return 0;
 536 }
 537
 538 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
 539 {
 540 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 541         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 542         if (uart->cts_pin < 0)
 543                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 544
 545         if (gpio_get_value(uart->cts_pin))
 546                 return TIOCM_DSR | TIOCM_CAR;
 547         else
 548 #endif
 549                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 550 }
 551
 552 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
 553 {
 554 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 555         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 556         if (uart->rts_pin < 0)
 557                 return;
 558
 559         if (mctrl & TIOCM_RTS)
 560                 gpio_set_value(uart->rts_pin, 0);
 561         else
 562                 gpio_set_value(uart->rts_pin, 1);
 563 #endif
 564 }
 565
 566 /*
 567  * Handle any change of modem status signal since we were last called.
 568  */
 569 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
 570 {
 571 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 572         unsigned int status;
 573 # ifdef CONFIG_SERIAL_BFIN_DMA
 574         struct uart_info *info = uart->port.info;
 575         struct tty_struct *tty = info->tty;
 576
 577         status = bfin_serial_get_mctrl(&uart->port);
 578         if (!(status & TIOCM_CTS)) {
 579                 tty->hw_stopped = 1;
 580         } else {
 581                 tty->hw_stopped = 0;
 582         }
 583 # else
 584         status = bfin_serial_get_mctrl(&uart->port);
 585         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
 586         if (!(status & TIOCM_CTS))
 587                 schedule_work(&uart->cts_workqueue);
 588 # endif
 589 #endif
 590 }
 591
 592 /*
 593  * Interrupts are always disabled.
 594  */
 595 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
 596 {
 597         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 598         u16 lcr = UART_GET_LCR(uart);
 599         if (break_state)
 600                 lcr |= SB;
 601         else
 602                 lcr &= ~SB;
 603         UART_PUT_LCR(uart, lcr);
 604         SSYNC();
 605 }
 606
 607 static int bfin_serial_startup(struct uart_port *port)
 608 {
 609         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 610
 611 #ifdef CONFIG_SERIAL_BFIN_DMA
 612         dma_addr_t dma_handle;
 613
 614         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
 615                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
 616                 return -EBUSY;
 617         }
 618
 619         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
 620                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
 621                 free_dma(uart->rx_dma_channel);
 622                 return -EBUSY;
 623         }
 624
 625         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
 626         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
 627
 628         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
 629         uart->rx_dma_buf.head = 0;
 630         uart->rx_dma_buf.tail = 0;
 631         uart->rx_dma_nrows = 0;
 632
 633         set_dma_config(uart->rx_dma_channel,
 634                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
 635                                 INTR_ON_ROW, DIMENSION_2D,
 636                                 DATA_SIZE_8));
 637         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
 638         set_dma_x_modify(uart->rx_dma_channel, 1);
 639         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
 640         set_dma_y_modify(uart->rx_dma_channel, 1);
 641         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
 642         enable_dma(uart->rx_dma_channel);
 643
 644         uart->rx_dma_timer.data = (unsigned long)(uart);
 645         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
 646         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
 647         add_timer(&(uart->rx_dma_timer));
 648 #else
 649 # ifdef CONFIG_KGDB_UART
 650         if (uart->port.line != CONFIG_KGDB_UART_PORT && request_irq
 651 # else
 652         if (request_irq
 653 # endif
 654             (uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
 655              "BFIN_UART_RX", uart)) {
 656                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
 657                 return -EBUSY;
 658         }
 659
 660         if (request_irq
 661             (uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
 662              "BFIN_UART_TX", uart)) {
 663                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
 664                 free_irq(uart->port.irq, uart);
 665                 return -EBUSY;
 666         }
 667 #endif
 668         UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
 669         return 0;
 670 }
 671
 672 static void bfin_serial_shutdown(struct uart_port *port)
 673 {
 674         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 675
 676 #ifdef CONFIG_SERIAL_BFIN_DMA
 677         disable_dma(uart->tx_dma_channel);
 678         free_dma(uart->tx_dma_channel);
 679         disable_dma(uart->rx_dma_channel);
 680         free_dma(uart->rx_dma_channel);
 681         del_timer(&(uart->rx_dma_timer));
 682 #else
 683 #ifdef  CONFIG_KGDB_UART
 684         if (uart->port.line != CONFIG_KGDB_UART_PORT)
 685 #endif
 686         free_irq(uart->port.irq, uart);
 687         free_irq(uart->port.irq+1, uart);
 688 #endif
 689 }
 690
 691 static void
 692 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
 693                    struct ktermios *old)
 694 {
 695         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 696         unsigned long flags;
 697         unsigned int baud, quot;
 698         unsigned short val, ier, lsr, lcr = 0;
 699
 700         switch (termios->c_cflag & CSIZE) {
 701         case CS8:
 702                 lcr = WLS(8);
 703                 break;
 704         case CS7:
 705                 lcr = WLS(7);
 706                 break;
 707         case CS6:
 708                 lcr = WLS(6);
 709                 break;
 710         case CS5:
 711                 lcr = WLS(5);
 712                 break;
 713         default:
 714                 printk(KERN_ERR "%s: word lengh not supported\n",
 715                         __FUNCTION__);
 716         }
 717
 718         if (termios->c_cflag & CSTOPB)
 719                 lcr |= STB;
 720         if (termios->c_cflag & PARENB)
 721                 lcr |= PEN;
 722         if (!(termios->c_cflag & PARODD))
 723                 lcr |= EPS;
 724         if (termios->c_cflag & CMSPAR)
 725                 lcr |= STP;
 726
 727         port->read_status_mask = OE;
 728         if (termios->c_iflag & INPCK)
 729                 port->read_status_mask |= (FE | PE);
 730         if (termios->c_iflag & (BRKINT | PARMRK))
 731                 port->read_status_mask |= BI;
 732
 733         /*
 734          * Characters to ignore
 735          */
 736         port->ignore_status_mask = 0;
 737         if (termios->c_iflag & IGNPAR)
 738                 port->ignore_status_mask |= FE | PE;
 739         if (termios->c_iflag & IGNBRK) {
 740                 port->ignore_status_mask |= BI;
 741                 /*
 742                  * If we're ignoring parity and break indicators,
 743                  * ignore overruns too (for real raw support).
 744                  */
 745                 if (termios->c_iflag & IGNPAR)
 746                         port->ignore_status_mask |= OE;
 747         }
 748
 749         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
 750         quot = uart_get_divisor(port, baud);
 751         spin_lock_irqsave(&uart->port.lock, flags);
 752
 753         do {
 754                 lsr = UART_GET_LSR(uart);
 755         } while (!(lsr & TEMT));
 756
 757         /* Disable UART */
 758         ier = UART_GET_IER(uart);
 759         UART_PUT_IER(uart, 0);
 760
 761         /* Set DLAB in LCR to Access DLL and DLH */
 762         val = UART_GET_LCR(uart);
 763         val |= DLAB;
 764         UART_PUT_LCR(uart, val);
 765         SSYNC();
 766
 767         UART_PUT_DLL(uart, quot & 0xFF);
 768         SSYNC();
 769         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
 770         SSYNC();
 771
 772         /* Clear DLAB in LCR to Access THR RBR IER */
 773         val = UART_GET_LCR(uart);
 774         val &= ~DLAB;
 775         UART_PUT_LCR(uart, val);
 776         SSYNC();
 777
 778         UART_PUT_LCR(uart, lcr);
 779
 780         /* Enable UART */
 781         UART_PUT_IER(uart, ier);
 782
 783         val = UART_GET_GCTL(uart);
 784         val |= UCEN;
 785         UART_PUT_GCTL(uart, val);
 786
 787         spin_unlock_irqrestore(&uart->port.lock, flags);
 788 }
 789
 790 static const char *bfin_serial_type(struct uart_port *port)
 791 {
 792         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 793
 794         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
 795 }
 796
 797 /*
 798  * Release the memory region(s) being used by 'port'.
 799  */
 800 static void bfin_serial_release_port(struct uart_port *port)
 801 {
 802 }
 803
 804 /*
 805  * Request the memory region(s) being used by 'port'.
 806  */
 807 static int bfin_serial_request_port(struct uart_port *port)
 808 {
 809         return 0;
 810 }
 811
 812 /*
 813  * Configure/autoconfigure the port.
 814  */
 815 static void bfin_serial_config_port(struct uart_port *port, int flags)
 816 {
 817         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 818
 819         if (flags & UART_CONFIG_TYPE &&
 820             bfin_serial_request_port(&uart->port) == 0)
 821                 uart->port.type = PORT_BFIN;
 822 }
 823
 824 /*
 825  * Verify the new serial_struct (for TIOCSSERIAL).
 826  * The only change we allow are to the flags and type, and
 827  * even then only between PORT_BFIN and PORT_UNKNOWN
 828  */
 829 static int
 830 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
 831 {
 832         return 0;
 833 }
 834
 835 static struct uart_ops bfin_serial_pops = {
 836         .tx_empty       = bfin_serial_tx_empty,
 837         .set_mctrl      = bfin_serial_set_mctrl,
 838         .get_mctrl      = bfin_serial_get_mctrl,
 839         .stop_tx        = bfin_serial_stop_tx,
 840         .start_tx       = bfin_serial_start_tx,
 841         .stop_rx        = bfin_serial_stop_rx,
 842         .enable_ms      = bfin_serial_enable_ms,
 843         .break_ctl      = bfin_serial_break_ctl,
 844         .startup        = bfin_serial_startup,
 845         .shutdown       = bfin_serial_shutdown,
 846         .set_termios    = bfin_serial_set_termios,
 847         .type           = bfin_serial_type,
 848         .release_port   = bfin_serial_release_port,
 849         .request_port   = bfin_serial_request_port,
 850         .config_port    = bfin_serial_config_port,
 851         .verify_port    = bfin_serial_verify_port,
 852 };
 853
 854 static void __init bfin_serial_init_ports(void)
 855 {
 856         static int first = 1;
 857         int i;
 858
 859         if (!first)
 860                 return;
 861         first = 0;
 862
 863         for (i = 0; i < nr_ports; i++) {
 864                 bfin_serial_ports[i].port.uartclk   = get_sclk();
 865                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
 866                 bfin_serial_ports[i].port.line      = i;
 867                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
 868                 bfin_serial_ports[i].port.membase   =
 869                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
 870                 bfin_serial_ports[i].port.mapbase   =
 871                         bfin_serial_resource[i].uart_base_addr;
 872                 bfin_serial_ports[i].port.irq       =
 873                         bfin_serial_resource[i].uart_irq;
 874                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
 875 #ifdef CONFIG_SERIAL_BFIN_DMA
 876                 bfin_serial_ports[i].tx_done        = 1;
 877                 bfin_serial_ports[i].tx_count       = 0;
 878                 bfin_serial_ports[i].tx_dma_channel =
 879                         bfin_serial_resource[i].uart_tx_dma_channel;
 880                 bfin_serial_ports[i].rx_dma_channel =
 881                         bfin_serial_resource[i].uart_rx_dma_channel;
 882                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
 883 #else
 884                 INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
 885 #endif
 886 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 887                 bfin_serial_ports[i].cts_pin        =
 888                         bfin_serial_resource[i].uart_cts_pin;
 889                 bfin_serial_ports[i].rts_pin        =
 890                         bfin_serial_resource[i].uart_rts_pin;
 891 #endif
 892                 bfin_serial_hw_init(&bfin_serial_ports[i]);
 893
 894         }
 895 }
 896
 897 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
 898 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
 899 {
 900         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
 901         while (!(UART_GET_LSR(uart)))
 902                 barrier();
 903         UART_PUT_CHAR(uart, ch);
 904         SSYNC();
 905 }
 906
 907 /*
 908  * Interrupts are disabled on entering
 909  */
 910 static void
 911 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
 912 {
 913         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
 914         int flags = 0;
 915
 916         spin_lock_irqsave(&uart->port.lock, flags);
 917         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
 918         spin_unlock_irqrestore(&uart->port.lock, flags);
 919
 920 }
 921
 922 /*
 923  * If the port was already initialised (eg, by a boot loader),
 924  * try to determine the current setup.
 925  */
 926 static void __init
 927 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
 928                            int *parity, int *bits)
 929 {
 930         unsigned short status;
 931
 932         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
 933         if (status == (ERBFI | ETBEI)) {
 934                 /* ok, the port was enabled */
 935                 unsigned short lcr, val;
 936                 unsigned short dlh, dll;
 937
 938                 lcr = UART_GET_LCR(uart);
 939
 940                 *parity = 'n';
 941                 if (lcr & PEN) {
 942                         if (lcr & EPS)
 943                                 *parity = 'e';
 944                         else
 945                                 *parity = 'o';
 946                 }
 947                 switch (lcr & 0x03) {
 948                         case 0: *bits = 5; break;
 949                         case 1: *bits = 6; break;
 950                         case 2: *bits = 7; break;
 951                         case 3: *bits = 8; break;
 952                 }
 953                 /* Set DLAB in LCR to Access DLL and DLH */
 954                 val = UART_GET_LCR(uart);
 955                 val |= DLAB;
 956                 UART_PUT_LCR(uart, val);
 957
 958                 dll = UART_GET_DLL(uart);
 959                 dlh = UART_GET_DLH(uart);
 960
 961                 /* Clear DLAB in LCR to Access THR RBR IER */
 962                 val = UART_GET_LCR(uart);
 963                 val &= ~DLAB;
 964                 UART_PUT_LCR(uart, val);
 965
 966                 *baud = get_sclk() / (16*(dll | dlh << 8));
 967         }
 968         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
 969 }
 970
 971 static int __init
 972 bfin_serial_console_setup(struct console *co, char *options)
 973 {
 974         struct bfin_serial_port *uart;
 975         int baud = 57600;
 976         int bits = 8;
 977         int parity = 'n';
 978 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
 979         int flow = 'r';
 980 #else
 981         int flow = 'n';
 982 #endif
 983
 984         /*
 985          * Check whether an invalid uart number has been specified, and
 986          * if so, search for the first available port that does have
 987          * console support.
 988          */
 989         if (co->index == -1 || co->index >= nr_ports)
 990                 co->index = 0;
 991         uart = &bfin_serial_ports[co->index];
 992
 993         if (options)
 994                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 995         else
 996                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
 997
 998         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
 999 }
1000
1001 static struct uart_driver bfin_serial_reg;
1002 static struct console bfin_serial_console = {
1003         .name           = BFIN_SERIAL_NAME,
1004         .write          = bfin_serial_console_write,
1005         .device         = uart_console_device,
1006         .setup          = bfin_serial_console_setup,
1007         .flags          = CON_PRINTBUFFER,
1008         .index          = -1,
1009         .data           = &bfin_serial_reg,
1010 };
1011
1012 static int __init bfin_serial_rs_console_init(void)
1013 {
1014         bfin_serial_init_ports();
1015         register_console(&bfin_serial_console);
1016 #ifdef CONFIG_KGDB_UART
1017         kgdb_entry_state = 0;
1018         init_kgdb_uart();
1019 #endif
1020         return 0;
1021 }
1022 console_initcall(bfin_serial_rs_console_init);
1023
1024 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
1025 #else
1026 #define BFIN_SERIAL_CONSOLE     NULL
1027 #endif
1028
1029 static struct uart_driver bfin_serial_reg = {
1030         .owner                  = THIS_MODULE,
1031         .driver_name            = "bfin-uart",
1032         .dev_name               = BFIN_SERIAL_NAME,
1033         .major                  = BFIN_SERIAL_MAJOR,
1034         .minor                  = BFIN_SERIAL_MINOR,
1035         .nr                     = NR_PORTS,
1036         .cons                   = BFIN_SERIAL_CONSOLE,
1037 };
1038
1039 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
1040 {
1041         struct bfin_serial_port *uart = platform_get_drvdata(dev);
1042
1043         if (uart)
1044                 uart_suspend_port(&bfin_serial_reg, &uart->port);
1045
1046         return 0;
1047 }
1048
1049 static int bfin_serial_resume(struct platform_device *dev)
1050 {
1051         struct bfin_serial_port *uart = platform_get_drvdata(dev);
1052
1053         if (uart)
1054                 uart_resume_port(&bfin_serial_reg, &uart->port);
1055
1056         return 0;
1057 }
1058
1059 static int bfin_serial_probe(struct platform_device *dev)
1060 {
1061         struct resource *res = dev->resource;
1062         int i;
1063
1064         for (i = 0; i < dev->num_resources; i++, res++)
1065                 if (res->flags & IORESOURCE_MEM)
1066                         break;
1067
1068         if (i < dev->num_resources) {
1069                 for (i = 0; i < nr_ports; i++, res++) {
1070                         if (bfin_serial_ports[i].port.mapbase != res->start)
1071                                 continue;
1072                         bfin_serial_ports[i].port.dev = &dev->dev;
1073                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1074                         platform_set_drvdata(dev, &bfin_serial_ports[i]);
1075                 }
1076         }
1077
1078         return 0;
1079 }
1080
1081 static int bfin_serial_remove(struct platform_device *pdev)
1082 {
1083         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
1084
1085
1086 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1087         gpio_free(uart->cts_pin);
1088         gpio_free(uart->rts_pin);
1089 #endif
1090
1091         platform_set_drvdata(pdev, NULL);
1092
1093         if (uart)
1094                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
1095
1096         return 0;
1097 }
1098
1099 static struct platform_driver bfin_serial_driver = {
1100         .probe          = bfin_serial_probe,
1101         .remove         = bfin_serial_remove,
1102         .suspend        = bfin_serial_suspend,
1103         .resume         = bfin_serial_resume,
1104         .driver         = {
1105                 .name   = "bfin-uart",
1106         },
1107 };
1108
1109 static int __init bfin_serial_init(void)
1110 {
1111         int ret;
1112 #ifdef CONFIG_KGDB_UART
1113         struct bfin_serial_port *uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
1114         struct termios t;
1115 #endif
1116
1117         pr_info("Serial: Blackfin serial driver\n");
1118
1119         bfin_serial_init_ports();
1120
1121         ret = uart_register_driver(&bfin_serial_reg);
1122         if (ret == 0) {
1123                 ret = platform_driver_register(&bfin_serial_driver);
1124                 if (ret) {
1125                         pr_debug("uart register failed\n");
1126                         uart_unregister_driver(&bfin_serial_reg);
1127                 }
1128         }
1129 #ifdef CONFIG_KGDB_UART
1130         if (uart->port.cons->index != CONFIG_KGDB_UART_PORT) {
1131                 request_irq(uart->port.irq, bfin_serial_int,
1132                         IRQF_DISABLED, "BFIN_UART_RX", uart);
1133                 pr_info("Request irq for kgdb uart port\n");
1134                 UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
1135                 __builtin_bfin_ssync();
1136                 t.c_cflag = CS8|B57600;
1137                 t.c_iflag = 0;
1138                 t.c_oflag = 0;
1139                 t.c_lflag = ICANON;
1140                 t.c_line = CONFIG_KGDB_UART_PORT;
1141                 bfin_serial_set_termios(&uart->port, &t, &t);
1142         }
1143 #endif
1144         return ret;
1145 }
1146
1147 static void __exit bfin_serial_exit(void)
1148 {
1149         platform_driver_unregister(&bfin_serial_driver);
1150         uart_unregister_driver(&bfin_serial_reg);
1151 }
1152
1153 module_init(bfin_serial_init);
1154 module_exit(bfin_serial_exit);
1155
1156 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1157 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1158 MODULE_LICENSE("GPL");
1159 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);