drivers/tty/serial/apbuart.c

   1 /*
   2  *  Driver for GRLIB serial ports (APBUART)
   3  *
   4  *  Based on linux/drivers/serial/amba.c
   5  *
   6  *  Copyright (C) 2000 Deep Blue Solutions Ltd.
   7  *  Copyright (C) 2003 Konrad Eisele <eiselekd@web.de>
   8  *  Copyright (C) 2006 Daniel Hellstrom <daniel@gaisler.com>, Aeroflex Gaisler AB
   9  *  Copyright (C) 2008 Gilead Kutnick <kutnickg@zin-tech.com>
  10  *  Copyright (C) 2009 Kristoffer Glembo <kristoffer@gaisler.com>, Aeroflex Gaisler AB
  11  */
  12
  13 #if defined(CONFIG_SERIAL_GRLIB_GAISLER_APBUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  14 #define SUPPORT_SYSRQ
  15 #endif
  16
  17 #include <linux/module.h>
  18 #include <linux/tty.h>
  19 #include <linux/tty_flip.h>
  20 #include <linux/ioport.h>
  21 #include <linux/init.h>
  22 #include <linux/serial.h>
  23 #include <linux/console.h>
  24 #include <linux/sysrq.h>
  25 #include <linux/kthread.h>
  26 #include <linux/device.h>
  27 #include <linux/of.h>
  28 #include <linux/of_device.h>
  29 #include <linux/of_platform.h>
  30 #include <linux/of_irq.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/io.h>
  33 #include <linux/serial_core.h>
  34 #include <asm/irq.h>
  35
  36 #include "apbuart.h"
  37
  38 #define SERIAL_APBUART_MAJOR    TTY_MAJOR
  39 #define SERIAL_APBUART_MINOR    64
  40 #define UART_DUMMY_RSR_RX       0x8000  /* for ignore all read */
  41
  42 static void apbuart_tx_chars(struct uart_port *port);
  43
  44 static void apbuart_stop_tx(struct uart_port *port)
  45 {
  46         unsigned int cr;
  47
  48         cr = UART_GET_CTRL(port);
  49         cr &= ~UART_CTRL_TI;
  50         UART_PUT_CTRL(port, cr);
  51 }
  52
  53 static void apbuart_start_tx(struct uart_port *port)
  54 {
  55         unsigned int cr;
  56
  57         cr = UART_GET_CTRL(port);
  58         cr |= UART_CTRL_TI;
  59         UART_PUT_CTRL(port, cr);
  60
  61         if (UART_GET_STATUS(port) & UART_STATUS_THE)
  62                 apbuart_tx_chars(port);
  63 }
  64
  65 static void apbuart_stop_rx(struct uart_port *port)
  66 {
  67         unsigned int cr;
  68
  69         cr = UART_GET_CTRL(port);
  70         cr &= ~(UART_CTRL_RI);
  71         UART_PUT_CTRL(port, cr);
  72 }
  73
  74 static void apbuart_enable_ms(struct uart_port *port)
  75 {
  76         /* No modem status change interrupts for APBUART */
  77 }
  78
  79 static void apbuart_rx_chars(struct uart_port *port)
  80 {
  81         unsigned int status, ch, rsr, flag;
  82         unsigned int max_chars = port->fifosize;
  83
  84         status = UART_GET_STATUS(port);
  85
  86         while (UART_RX_DATA(status) && (max_chars--)) {
  87
  88                 ch = UART_GET_CHAR(port);
  89                 flag = TTY_NORMAL;
  90
  91                 port->icount.rx++;
  92
  93                 rsr = UART_GET_STATUS(port) | UART_DUMMY_RSR_RX;
  94                 UART_PUT_STATUS(port, 0);
  95                 if (rsr & UART_STATUS_ERR) {
  96
  97                         if (rsr & UART_STATUS_BR) {
  98                                 rsr &= ~(UART_STATUS_FE | UART_STATUS_PE);
  99                                 port->icount.brk++;
 100                                 if (uart_handle_break(port))
 101                                         goto ignore_char;
 102                         } else if (rsr & UART_STATUS_PE) {
 103                                 port->icount.parity++;
 104                         } else if (rsr & UART_STATUS_FE) {
 105                                 port->icount.frame++;
 106                         }
 107                         if (rsr & UART_STATUS_OE)
 108                                 port->icount.overrun++;
 109
 110                         rsr &= port->read_status_mask;
 111
 112                         if (rsr & UART_STATUS_PE)
 113                                 flag = TTY_PARITY;
 114                         else if (rsr & UART_STATUS_FE)
 115                                 flag = TTY_FRAME;
 116                 }
 117
 118                 if (uart_handle_sysrq_char(port, ch))
 119                         goto ignore_char;
 120
 121                 uart_insert_char(port, rsr, UART_STATUS_OE, ch, flag);
 122
 123
 124               ignore_char:
 125                 status = UART_GET_STATUS(port);
 126         }
 127
 128         spin_unlock(&port->lock);
 129         tty_flip_buffer_push(&port->state->port);
 130         spin_lock(&port->lock);
 131 }
 132
 133 static void apbuart_tx_chars(struct uart_port *port)
 134 {
 135         struct circ_buf *xmit = &port->state->xmit;
 136         int count;
 137
 138         if (port->x_char) {
 139                 UART_PUT_CHAR(port, port->x_char);
 140                 port->icount.tx++;
 141                 port->x_char = 0;
 142                 return;
 143         }
 144
 145         if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
 146                 apbuart_stop_tx(port);
 147                 return;
 148         }
 149
 150         /* amba: fill FIFO */
 151         count = port->fifosize >> 1;
 152         do {
 153                 UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
 154                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 155                 port->icount.tx++;
 156                 if (uart_circ_empty(xmit))
 157                         break;
 158         } while (--count > 0);
 159
 160         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 161                 uart_write_wakeup(port);
 162
 163         if (uart_circ_empty(xmit))
 164                 apbuart_stop_tx(port);
 165 }
 166
 167 static irqreturn_t apbuart_int(int irq, void *dev_id)
 168 {
 169         struct uart_port *port = dev_id;
 170         unsigned int status;
 171
 172         spin_lock(&port->lock);
 173
 174         status = UART_GET_STATUS(port);
 175         if (status & UART_STATUS_DR)
 176                 apbuart_rx_chars(port);
 177         if (status & UART_STATUS_THE)
 178                 apbuart_tx_chars(port);
 179
 180         spin_unlock(&port->lock);
 181
 182         return IRQ_HANDLED;
 183 }
 184
 185 static unsigned int apbuart_tx_empty(struct uart_port *port)
 186 {
 187         unsigned int status = UART_GET_STATUS(port);
 188         return status & UART_STATUS_THE ? TIOCSER_TEMT : 0;
 189 }
 190
 191 static unsigned int apbuart_get_mctrl(struct uart_port *port)
 192 {
 193         /* The GRLIB APBUART handles flow control in hardware */
 194         return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 195 }
 196
 197 static void apbuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
 198 {
 199         /* The GRLIB APBUART handles flow control in hardware */
 200 }
 201
 202 static void apbuart_break_ctl(struct uart_port *port, int break_state)
 203 {
 204         /* We don't support sending break */
 205 }
 206
 207 static int apbuart_startup(struct uart_port *port)
 208 {
 209         int retval;
 210         unsigned int cr;
 211
 212         /* Allocate the IRQ */
 213         retval = request_irq(port->irq, apbuart_int, 0, "apbuart", port);
 214         if (retval)
 215                 return retval;
 216
 217         /* Finally, enable interrupts */
 218         cr = UART_GET_CTRL(port);
 219         UART_PUT_CTRL(port,
 220                       cr | UART_CTRL_RE | UART_CTRL_TE |
 221                       UART_CTRL_RI | UART_CTRL_TI);
 222
 223         return 0;
 224 }
 225
 226 static void apbuart_shutdown(struct uart_port *port)
 227 {
 228         unsigned int cr;
 229
 230         /* disable all interrupts, disable the port */
 231         cr = UART_GET_CTRL(port);
 232         UART_PUT_CTRL(port,
 233                       cr & ~(UART_CTRL_RE | UART_CTRL_TE |
 234                              UART_CTRL_RI | UART_CTRL_TI));
 235
 236         /* Free the interrupt */
 237         free_irq(port->irq, port);
 238 }
 239
 240 static void apbuart_set_termios(struct uart_port *port,
 241                                 struct ktermios *termios, struct ktermios *old)
 242 {
 243         unsigned int cr;
 244         unsigned long flags;
 245         unsigned int baud, quot;
 246
 247         /* Ask the core to calculate the divisor for us. */
 248         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
 249         if (baud == 0)
 250                 panic("invalid baudrate %i\n", port->uartclk / 16);
 251
 252         /* uart_get_divisor calc a *16 uart freq, apbuart is *8 */
 253         quot = (uart_get_divisor(port, baud)) * 2;
 254         cr = UART_GET_CTRL(port);
 255         cr &= ~(UART_CTRL_PE | UART_CTRL_PS);
 256
 257         if (termios->c_cflag & PARENB) {
 258                 cr |= UART_CTRL_PE;
 259                 if ((termios->c_cflag & PARODD))
 260                         cr |= UART_CTRL_PS;
 261         }
 262
 263         /* Enable flow control. */
 264         if (termios->c_cflag & CRTSCTS)
 265                 cr |= UART_CTRL_FL;
 266
 267         spin_lock_irqsave(&port->lock, flags);
 268
 269         /* Update the per-port timeout. */
 270         uart_update_timeout(port, termios->c_cflag, baud);
 271
 272         port->read_status_mask = UART_STATUS_OE;
 273         if (termios->c_iflag & INPCK)
 274                 port->read_status_mask |= UART_STATUS_FE | UART_STATUS_PE;
 275
 276         /* Characters to ignore */
 277         port->ignore_status_mask = 0;
 278         if (termios->c_iflag & IGNPAR)
 279                 port->ignore_status_mask |= UART_STATUS_FE | UART_STATUS_PE;
 280
 281         /* Ignore all characters if CREAD is not set. */
 282         if ((termios->c_cflag & CREAD) == 0)
 283                 port->ignore_status_mask |= UART_DUMMY_RSR_RX;
 284
 285         /* Set baud rate */
 286         quot -= 1;
 287         UART_PUT_SCAL(port, quot);
 288         UART_PUT_CTRL(port, cr);
 289
 290         spin_unlock_irqrestore(&port->lock, flags);
 291 }
 292
 293 static const char *apbuart_type(struct uart_port *port)
 294 {
 295         return port->type == PORT_APBUART ? "GRLIB/APBUART" : NULL;
 296 }
 297
 298 static void apbuart_release_port(struct uart_port *port)
 299 {
 300         release_mem_region(port->mapbase, 0x100);
 301 }
 302
 303 static int apbuart_request_port(struct uart_port *port)
 304 {
 305         return request_mem_region(port->mapbase, 0x100, "grlib-apbuart")
 306             != NULL ? 0 : -EBUSY;
 307         return 0;
 308 }
 309
 310 /* Configure/autoconfigure the port */
 311 static void apbuart_config_port(struct uart_port *port, int flags)
 312 {
 313         if (flags & UART_CONFIG_TYPE) {
 314                 port->type = PORT_APBUART;
 315                 apbuart_request_port(port);
 316         }
 317 }
 318
 319 /* Verify the new serial_struct (for TIOCSSERIAL) */
 320 static int apbuart_verify_port(struct uart_port *port,
 321                                struct serial_struct *ser)
 322 {
 323         int ret = 0;
 324         if (ser->type != PORT_UNKNOWN && ser->type != PORT_APBUART)
 325                 ret = -EINVAL;
 326         if (ser->irq < 0 || ser->irq >= NR_IRQS)
 327                 ret = -EINVAL;
 328         if (ser->baud_base < 9600)
 329                 ret = -EINVAL;
 330         return ret;
 331 }
 332
 333 static struct uart_ops grlib_apbuart_ops = {
 334         .tx_empty = apbuart_tx_empty,
 335         .set_mctrl = apbuart_set_mctrl,
 336         .get_mctrl = apbuart_get_mctrl,
 337         .stop_tx = apbuart_stop_tx,
 338         .start_tx = apbuart_start_tx,
 339         .stop_rx = apbuart_stop_rx,
 340         .enable_ms = apbuart_enable_ms,
 341         .break_ctl = apbuart_break_ctl,
 342         .startup = apbuart_startup,
 343         .shutdown = apbuart_shutdown,
 344         .set_termios = apbuart_set_termios,
 345         .type = apbuart_type,
 346         .release_port = apbuart_release_port,
 347         .request_port = apbuart_request_port,
 348         .config_port = apbuart_config_port,
 349         .verify_port = apbuart_verify_port,
 350 };
 351
 352 static struct uart_port grlib_apbuart_ports[UART_NR];
 353 static struct device_node *grlib_apbuart_nodes[UART_NR];
 354
 355 static int apbuart_scan_fifo_size(struct uart_port *port, int portnumber)
 356 {
 357         int ctrl, loop = 0;
 358         int status;
 359         int fifosize;
 360         unsigned long flags;
 361
 362         ctrl = UART_GET_CTRL(port);
 363
 364         /*
 365          * Enable the transceiver and wait for it to be ready to send data.
 366          * Clear interrupts so that this process will not be externally
 367          * interrupted in the middle (which can cause the transceiver to
 368          * drain prematurely).
 369          */
 370
 371         local_irq_save(flags);
 372
 373         UART_PUT_CTRL(port, ctrl | UART_CTRL_TE);
 374
 375         while (!UART_TX_READY(UART_GET_STATUS(port)))
 376                 loop++;
 377
 378         /*
 379          * Disable the transceiver so data isn't actually sent during the
 380          * actual test.
 381          */
 382
 383         UART_PUT_CTRL(port, ctrl & ~(UART_CTRL_TE));
 384
 385         fifosize = 1;
 386         UART_PUT_CHAR(port, 0);
 387
 388         /*
 389          * So long as transmitting a character increments the tranceivier FIFO
 390          * length the FIFO must be at least that big. These bytes will
 391          * automatically drain off of the FIFO.
 392          */
 393
 394         status = UART_GET_STATUS(port);
 395         while (((status >> 20) & 0x3F) == fifosize) {
 396                 fifosize++;
 397                 UART_PUT_CHAR(port, 0);
 398                 status = UART_GET_STATUS(port);
 399         }
 400
 401         fifosize--;
 402
 403         UART_PUT_CTRL(port, ctrl);
 404         local_irq_restore(flags);
 405
 406         if (fifosize == 0)
 407                 fifosize = 1;
 408
 409         return fifosize;
 410 }
 411
 412 static void apbuart_flush_fifo(struct uart_port *port)
 413 {
 414         int i;
 415
 416         for (i = 0; i < port->fifosize; i++)
 417                 UART_GET_CHAR(port);
 418 }
 419
 420
 421 /* ======================================================================== */
 422 /* Console driver, if enabled                                               */
 423 /* ======================================================================== */
 424
 425 #ifdef CONFIG_SERIAL_GRLIB_GAISLER_APBUART_CONSOLE
 426
 427 static void apbuart_console_putchar(struct uart_port *port, int ch)
 428 {
 429         unsigned int status;
 430         do {
 431                 status = UART_GET_STATUS(port);
 432         } while (!UART_TX_READY(status));
 433         UART_PUT_CHAR(port, ch);
 434 }
 435
 436 static void
 437 apbuart_console_write(struct console *co, const char *s, unsigned int count)
 438 {
 439         struct uart_port *port = &grlib_apbuart_ports[co->index];
 440         unsigned int status, old_cr, new_cr;
 441
 442         /* First save the CR then disable the interrupts */
 443         old_cr = UART_GET_CTRL(port);
 444         new_cr = old_cr & ~(UART_CTRL_RI | UART_CTRL_TI);
 445         UART_PUT_CTRL(port, new_cr);
 446
 447         uart_console_write(port, s, count, apbuart_console_putchar);
 448
 449         /*
 450          *      Finally, wait for transmitter to become empty
 451          *      and restore the TCR
 452          */
 453         do {
 454                 status = UART_GET_STATUS(port);
 455         } while (!UART_TX_READY(status));
 456         UART_PUT_CTRL(port, old_cr);
 457 }
 458
 459 static void __init
 460 apbuart_console_get_options(struct uart_port *port, int *baud,
 461                             int *parity, int *bits)
 462 {
 463         if (UART_GET_CTRL(port) & (UART_CTRL_RE | UART_CTRL_TE)) {
 464
 465                 unsigned int quot, status;
 466                 status = UART_GET_STATUS(port);
 467
 468                 *parity = 'n';
 469                 if (status & UART_CTRL_PE) {
 470                         if ((status & UART_CTRL_PS) == 0)
 471                                 *parity = 'e';
 472                         else
 473                                 *parity = 'o';
 474                 }
 475
 476                 *bits = 8;
 477                 quot = UART_GET_SCAL(port) / 8;
 478                 *baud = port->uartclk / (16 * (quot + 1));
 479         }
 480 }
 481
 482 static int __init apbuart_console_setup(struct console *co, char *options)
 483 {
 484         struct uart_port *port;
 485         int baud = 38400;
 486         int bits = 8;
 487         int parity = 'n';
 488         int flow = 'n';
 489
 490         pr_debug("apbuart_console_setup co=%p, co->index=%i, options=%s\n",
 491                  co, co->index, options);
 492
 493         /*
 494          * Check whether an invalid uart number has been specified, and
 495          * if so, search for the first available port that does have
 496          * console support.
 497          */
 498         if (co->index >= grlib_apbuart_port_nr)
 499                 co->index = 0;
 500
 501         port = &grlib_apbuart_ports[co->index];
 502
 503         spin_lock_init(&port->lock);
 504
 505         if (options)
 506                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 507         else
 508                 apbuart_console_get_options(port, &baud, &parity, &bits);
 509
 510         return uart_set_options(port, co, baud, parity, bits, flow);
 511 }
 512
 513 static struct uart_driver grlib_apbuart_driver;
 514
 515 static struct console grlib_apbuart_console = {
 516         .name = "ttyS",
 517         .write = apbuart_console_write,
 518         .device = uart_console_device,
 519         .setup = apbuart_console_setup,
 520         .flags = CON_PRINTBUFFER,
 521         .index = -1,
 522         .data = &grlib_apbuart_driver,
 523 };
 524
 525
 526 static int grlib_apbuart_configure(void);
 527
 528 static int __init apbuart_console_init(void)
 529 {
 530         if (grlib_apbuart_configure())
 531                 return -ENODEV;
 532         register_console(&grlib_apbuart_console);
 533         return 0;
 534 }
 535
 536 console_initcall(apbuart_console_init);
 537
 538 #define APBUART_CONSOLE (&grlib_apbuart_console)
 539 #else
 540 #define APBUART_CONSOLE NULL
 541 #endif
 542
 543 static struct uart_driver grlib_apbuart_driver = {
 544         .owner = THIS_MODULE,
 545         .driver_name = "serial",
 546         .dev_name = "ttyS",
 547         .major = SERIAL_APBUART_MAJOR,
 548         .minor = SERIAL_APBUART_MINOR,
 549         .nr = UART_NR,
 550         .cons = APBUART_CONSOLE,
 551 };
 552
 553
 554 /* ======================================================================== */
 555 /* OF Platform Driver                                                       */
 556 /* ======================================================================== */
 557
 558 static int apbuart_probe(struct platform_device *op)
 559 {
 560         int i;
 561         struct uart_port *port = NULL;
 562
 563         for (i = 0; i < grlib_apbuart_port_nr; i++) {
 564                 if (op->dev.of_node == grlib_apbuart_nodes[i])
 565                         break;
 566         }
 567
 568         port = &grlib_apbuart_ports[i];
 569         port->dev = &op->dev;
 570         port->irq = op->archdata.irqs[0];
 571
 572         uart_add_one_port(&grlib_apbuart_driver, (struct uart_port *) port);
 573
 574         apbuart_flush_fifo((struct uart_port *) port);
 575
 576         printk(KERN_INFO "grlib-apbuart at 0x%llx, irq %d\n",
 577                (unsigned long long) port->mapbase, port->irq);
 578         return 0;
 579 }
 580
 581 static struct of_device_id apbuart_match[] = {
 582         {
 583          .name = "GAISLER_APBUART",
 584          },
 585         {
 586          .name = "01_00c",
 587          },
 588         {},
 589 };
 590
 591 static struct platform_driver grlib_apbuart_of_driver = {
 592         .probe = apbuart_probe,
 593         .driver = {
 594                 .owner = THIS_MODULE,
 595                 .name = "grlib-apbuart",
 596                 .of_match_table = apbuart_match,
 597         },
 598 };
 599
 600
 601 static int __init grlib_apbuart_configure(void)
 602 {
 603         struct device_node *np;
 604         int line = 0;
 605
 606         for_each_matching_node(np, apbuart_match) {
 607                 const int *ampopts;
 608                 const u32 *freq_hz;
 609                 const struct amba_prom_registers *regs;
 610                 struct uart_port *port;
 611                 unsigned long addr;
 612
 613                 ampopts = of_get_property(np, "ampopts", NULL);
 614                 if (ampopts && (*ampopts == 0))
 615                         continue; /* Ignore if used by another OS instance */
 616                 regs = of_get_property(np, "reg", NULL);
 617                 /* Frequency of APB Bus is frequency of UART */
 618                 freq_hz = of_get_property(np, "freq", NULL);
 619
 620                 if (!regs || !freq_hz || (*freq_hz == 0))
 621                         continue;
 622
 623                 grlib_apbuart_nodes[line] = np;
 624
 625                 addr = regs->phys_addr;
 626
 627                 port = &grlib_apbuart_ports[line];
 628
 629                 port->mapbase = addr;
 630                 port->membase = ioremap(addr, sizeof(struct grlib_apbuart_regs_map));
 631                 port->irq = 0;
 632                 port->iotype = UPIO_MEM;
 633                 port->ops = &grlib_apbuart_ops;
 634                 port->flags = UPF_BOOT_AUTOCONF;
 635                 port->line = line;
 636                 port->uartclk = *freq_hz;
 637                 port->fifosize = apbuart_scan_fifo_size((struct uart_port *) port, line);
 638                 line++;
 639
 640                 /* We support maximum UART_NR uarts ... */
 641                 if (line == UART_NR)
 642                         break;
 643         }
 644
 645         grlib_apbuart_driver.nr = grlib_apbuart_port_nr = line;
 646         return line ? 0 : -ENODEV;
 647 }
 648
 649 static int __init grlib_apbuart_init(void)
 650 {
 651         int ret;
 652
 653         /* Find all APBUARTS in device the tree and initialize their ports */
 654         ret = grlib_apbuart_configure();
 655         if (ret)
 656                 return ret;
 657
 658         printk(KERN_INFO "Serial: GRLIB APBUART driver\n");
 659
 660         ret = uart_register_driver(&grlib_apbuart_driver);
 661
 662         if (ret) {
 663                 printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
 664                        __FILE__, ret);
 665                 return ret;
 666         }
 667
 668         ret = platform_driver_register(&grlib_apbuart_of_driver);
 669         if (ret) {
 670                 printk(KERN_ERR
 671                        "%s: platform_driver_register failed (%i)\n",
 672                        __FILE__, ret);
 673                 uart_unregister_driver(&grlib_apbuart_driver);
 674                 return ret;
 675         }
 676
 677         return ret;
 678 }
 679
 680 static void __exit grlib_apbuart_exit(void)
 681 {
 682         int i;
 683
 684         for (i = 0; i < grlib_apbuart_port_nr; i++)
 685                 uart_remove_one_port(&grlib_apbuart_driver,
 686                                      &grlib_apbuart_ports[i]);
 687
 688         uart_unregister_driver(&grlib_apbuart_driver);
 689         platform_driver_unregister(&grlib_apbuart_of_driver);
 690 }
 691
 692 module_init(grlib_apbuart_init);
 693 module_exit(grlib_apbuart_exit);
 694
 695 MODULE_AUTHOR("Aeroflex Gaisler AB");
 696 MODULE_DESCRIPTION("GRLIB APBUART serial driver");
 697 MODULE_VERSION("2.1");
 698 MODULE_LICENSE("GPL");