diff options
Diffstat (limited to 'drivers/serial/dz.c')
| -rw-r--r-- | drivers/serial/dz.c | 822 |
1 files changed, 822 insertions, 0 deletions
diff --git a/drivers/serial/dz.c b/drivers/serial/dz.c new file mode 100644 index 00000000000..97824eeeafa --- /dev/null +++ b/drivers/serial/dz.c @@ -0,0 +1,822 @@ +/* + * dz.c: Serial port driver for DECStations equiped + * with the DZ chipset. + * + * Copyright (C) 1998 Olivier A. D. Lebaillif + * + * Email: olivier.lebaillif@ifrsys.com + * + * [31-AUG-98] triemer + * Changed IRQ to use Harald's dec internals interrupts.h + * removed base_addr code - moving address assignment to setup.c + * Changed name of dz_init to rs_init to be consistent with tc code + * [13-NOV-98] triemer fixed code to receive characters + * after patches by harald to irq code. + * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout + * field from "current" - somewhere between 2.1.121 and 2.1.131 + Qua Jun 27 15:02:26 BRT 2001 + * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups + * + * Parts (C) 1999 David Airlie, airlied@linux.ie + * [07-SEP-99] Bugfixes + * + * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk> + * Converted to new serial core + */ + +#undef DEBUG_DZ + +#include <linux/config.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/console.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/serial_core.h> +#include <linux/serial.h> + +#include <asm/bootinfo.h> +#include <asm/dec/interrupts.h> +#include <asm/dec/kn01.h> +#include <asm/dec/kn02.h> +#include <asm/dec/machtype.h> +#include <asm/dec/prom.h> +#include <asm/irq.h> +#include <asm/system.h> +#include <asm/uaccess.h> + +#define CONSOLE_LINE (3) /* for definition of struct console */ + +#include "dz.h" + +#define DZ_INTR_DEBUG 1 + +static char *dz_name = "DECstation DZ serial driver version "; +static char *dz_version = "1.02"; + +struct dz_port { + struct uart_port port; + unsigned int cflag; +}; + +static struct dz_port dz_ports[DZ_NB_PORT]; + +#ifdef DEBUG_DZ +/* + * debugging code to send out chars via prom + */ +static void debug_console(const char *s, int count) +{ + unsigned i; + + for (i = 0; i < count; i++) { + if (*s == 10) + prom_printf("%c", 13); + prom_printf("%c", *s++); + } +} +#endif + +/* + * ------------------------------------------------------------ + * dz_in () and dz_out () + * + * These routines are used to access the registers of the DZ + * chip, hiding relocation differences between implementation. + * ------------------------------------------------------------ + */ + +static inline unsigned short dz_in(struct dz_port *dport, unsigned offset) +{ + volatile unsigned short *addr = + (volatile unsigned short *) (dport->port.membase + offset); + return *addr; +} + +static inline void dz_out(struct dz_port *dport, unsigned offset, + unsigned short value) +{ + volatile unsigned short *addr = + (volatile unsigned short *) (dport->port.membase + offset); + *addr = value; +} + +/* + * ------------------------------------------------------------ + * rs_stop () and rs_start () + * + * These routines are called before setting or resetting + * tty->stopped. They enable or disable transmitter interrupts, + * as necessary. + * ------------------------------------------------------------ + */ + +static void dz_stop_tx(struct uart_port *uport, unsigned int tty_stop) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned short tmp, mask = 1 << dport->port.line; + unsigned long flags; + + spin_lock_irqsave(&dport->port.lock, flags); + tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ + tmp &= ~mask; /* clear the TX flag */ + dz_out(dport, DZ_TCR, tmp); + spin_unlock_irqrestore(&dport->port.lock, flags); +} + +static void dz_start_tx(struct uart_port *uport, unsigned int tty_start) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned short tmp, mask = 1 << dport->port.line; + unsigned long flags; + + spin_lock_irqsave(&dport->port.lock, flags); + tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ + tmp |= mask; /* set the TX flag */ + dz_out(dport, DZ_TCR, tmp); + spin_unlock_irqrestore(&dport->port.lock, flags); +} + +static void dz_stop_rx(struct uart_port *uport) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned long flags; + + spin_lock_irqsave(&dport->port.lock, flags); + dport->cflag &= ~DZ_CREAD; + dz_out(dport, DZ_LPR, dport->cflag); + spin_unlock_irqrestore(&dport->port.lock, flags); +} + +static void dz_enable_ms(struct uart_port *port) +{ + /* nothing to do */ +} + +/* + * ------------------------------------------------------------ + * Here starts the interrupt handling routines. All of the + * following subroutines are declared as inline and are folded + * into dz_interrupt. They were separated out for readability's + * sake. + * + * Note: rs_interrupt() is a "fast" interrupt, which means that it + * runs with interrupts turned off. People who may want to modify + * rs_interrupt() should try to keep the interrupt handler as fast as + * possible. After you are done making modifications, it is not a bad + * idea to do: + * + * make drivers/serial/dz.s + * + * and look at the resulting assemble code in dz.s. + * + * ------------------------------------------------------------ + */ + +/* + * ------------------------------------------------------------ + * receive_char () + * + * This routine deals with inputs from any lines. + * ------------------------------------------------------------ + */ +static inline void dz_receive_chars(struct dz_port *dport) +{ + struct tty_struct *tty = NULL; + struct uart_icount *icount; + int ignore = 0; + unsigned short status, tmp; + unsigned char ch, flag; + + /* this code is going to be a problem... + the call to tty_flip_buffer is going to need + to be rethought... + */ + do { + status = dz_in(dport, DZ_RBUF); + + /* punt so we don't get duplicate characters */ + if (!(status & DZ_DVAL)) + goto ignore_char; + + + ch = UCHAR(status); /* grab the char */ + flag = TTY_NORMAL; + +#if 0 + if (info->is_console) { + if (ch == 0) + return; /* it's a break ... */ + } +#endif + + tty = dport->port.info->tty;/* now tty points to the proper dev */ + icount = &dport->port.icount; + + if (!tty) + break; + if (tty->flip.count >= TTY_FLIPBUF_SIZE) + break; + + icount->rx++; + + /* keep track of the statistics */ + if (status & (DZ_OERR | DZ_FERR | DZ_PERR)) { + if (status & DZ_PERR) /* parity error */ + icount->parity++; + else if (status & DZ_FERR) /* frame error */ + icount->frame++; + if (status & DZ_OERR) /* overrun error */ + icount->overrun++; + + /* check to see if we should ignore the character + and mask off conditions that should be ignored + */ + + if (status & dport->port.ignore_status_mask) { + if (++ignore > 100) + break; + goto ignore_char; + } + /* mask off the error conditions we want to ignore */ + tmp = status & dport->port.read_status_mask; + + if (tmp & DZ_PERR) { + flag = TTY_PARITY; +#ifdef DEBUG_DZ + debug_console("PERR\n", 5); +#endif + } else if (tmp & DZ_FERR) { + flag = TTY_FRAME; +#ifdef DEBUG_DZ + debug_console("FERR\n", 5); +#endif + } + if (tmp & DZ_OERR) { +#ifdef DEBUG_DZ + debug_console("OERR\n", 5); +#endif + tty_insert_flip_char(tty, ch, flag); + ch = 0; + flag = TTY_OVERRUN; + } + } + tty_insert_flip_char(tty, ch, flag); + ignore_char: + } while (status & DZ_DVAL); + + if (tty) + tty_flip_buffer_push(tty); +} + +/* + * ------------------------------------------------------------ + * transmit_char () + * + * This routine deals with outputs to any lines. + * ------------------------------------------------------------ + */ +static inline void dz_transmit_chars(struct dz_port *dport) +{ + struct circ_buf *xmit = &dport->port.info->xmit; + unsigned char tmp; + + if (dport->port.x_char) { /* XON/XOFF chars */ + dz_out(dport, DZ_TDR, dport->port.x_char); + dport->port.icount.tx++; + dport->port.x_char = 0; + return; + } + /* if nothing to do or stopped or hardware stopped */ + if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) { + dz_stop_tx(&dport->port, 0); + return; + } + + /* + * if something to do ... (rember the dz has no output fifo so we go + * one char at a time :-< + */ + tmp = xmit->buf[xmit->tail]; + xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1); + dz_out(dport, DZ_TDR, tmp); + dport->port.icount.tx++; + + if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS) + uart_write_wakeup(&dport->port); + + /* Are we done */ + if (uart_circ_empty(xmit)) + dz_stop_tx(&dport->port, 0); +} + +/* + * ------------------------------------------------------------ + * check_modem_status () + * + * Only valid for the MODEM line duh ! + * ------------------------------------------------------------ + */ +static inline void check_modem_status(struct dz_port *dport) +{ + unsigned short status; + + /* if not ne modem line just return */ + if (dport->port.line != DZ_MODEM) + return; + + status = dz_in(dport, DZ_MSR); + + /* it's easy, since DSR2 is the only bit in the register */ + if (status) + dport->port.icount.dsr++; +} + +/* + * ------------------------------------------------------------ + * dz_interrupt () + * + * this is the main interrupt routine for the DZ chip. + * It deals with the multiple ports. + * ------------------------------------------------------------ + */ +static irqreturn_t dz_interrupt(int irq, void *dev, struct pt_regs *regs) +{ + struct dz_port *dport; + unsigned short status; + + /* get the reason why we just got an irq */ + status = dz_in((struct dz_port *)dev, DZ_CSR); + dport = &dz_ports[LINE(status)]; + + if (status & DZ_RDONE) + dz_receive_chars(dport); + + if (status & DZ_TRDY) + dz_transmit_chars(dport); + + /* FIXME: what about check modem status??? --rmk */ + + return IRQ_HANDLED; +} + +/* + * ------------------------------------------------------------------- + * Here ends the DZ interrupt routines. + * ------------------------------------------------------------------- + */ + +static unsigned int dz_get_mctrl(struct uart_port *uport) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + + if (dport->port.line == DZ_MODEM) { + /* + * CHECKME: This is a guess from the other code... --rmk + */ + if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR) + mctrl &= ~TIOCM_DSR; + } + + return mctrl; +} + +static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned short tmp; + + if (dport->port.line == DZ_MODEM) { + tmp = dz_in(dport, DZ_TCR); + if (mctrl & TIOCM_DTR) + tmp &= ~DZ_MODEM_DTR; + else + tmp |= DZ_MODEM_DTR; + dz_out(dport, DZ_TCR, tmp); + } +} + +/* + * ------------------------------------------------------------------- + * startup () + * + * various initialization tasks + * ------------------------------------------------------------------- + */ +static int dz_startup(struct uart_port *uport) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned long flags; + unsigned short tmp; + + /* The dz lines for the mouse/keyboard must be + * opened using their respective drivers. + */ + if ((dport->port.line == DZ_KEYBOARD) || + (dport->port.line == DZ_MOUSE)) + return -ENODEV; + + spin_lock_irqsave(&dport->port.lock, flags); + + /* enable the interrupt and the scanning */ + tmp = dz_in(dport, DZ_CSR); + tmp |= DZ_RIE | DZ_TIE | DZ_MSE; + dz_out(dport, DZ_CSR, tmp); + + spin_unlock_irqrestore(&dport->port.lock, flags); + + return 0; +} + +/* + * ------------------------------------------------------------------- + * shutdown () + * + * This routine will shutdown a serial port; interrupts are disabled, and + * DTR is dropped if the hangup on close termio flag is on. + * ------------------------------------------------------------------- + */ +static void dz_shutdown(struct uart_port *uport) +{ + dz_stop_tx(uport, 0); +} + +/* + * get_lsr_info - get line status register info + * + * Purpose: Let user call ioctl() to get info when the UART physically + * is emptied. On bus types like RS485, the transmitter must + * release the bus after transmitting. This must be done when + * the transmit shift register is empty, not be done when the + * transmit holding register is empty. This functionality + * allows an RS485 driver to be written in user space. + */ +static unsigned int dz_tx_empty(struct uart_port *uport) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned short status = dz_in(dport, DZ_LPR); + + /* FIXME: this appears to be obviously broken --rmk. */ + return status ? TIOCSER_TEMT : 0; +} + +static void dz_break_ctl(struct uart_port *uport, int break_state) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned long flags; + unsigned short tmp, mask = 1 << uport->line; + + spin_lock_irqsave(&uport->lock, flags); + tmp = dz_in(dport, DZ_TCR); + if (break_state) + tmp |= mask; + else + tmp &= ~mask; + dz_out(dport, DZ_TCR, tmp); + spin_unlock_irqrestore(&uport->lock, flags); +} + +static void dz_set_termios(struct uart_port *uport, struct termios *termios, + struct termios *old_termios) +{ + struct dz_port *dport = (struct dz_port *)uport; + unsigned long flags; + unsigned int cflag, baud; + + cflag = dport->port.line; + + switch (termios->c_cflag & CSIZE) { + case CS5: + cflag |= DZ_CS5; + break; + case CS6: + cflag |= DZ_CS6; + break; + case CS7: + cflag |= DZ_CS7; + break; + case CS8: + default: + cflag |= DZ_CS8; + } + + if (termios->c_cflag & CSTOPB) + cflag |= DZ_CSTOPB; + if (termios->c_cflag & PARENB) + cflag |= DZ_PARENB; + if (termios->c_cflag & PARODD) + cflag |= DZ_PARODD; + + baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600); + switch (baud) { + case 50: + cflag |= DZ_B50; + break; + case 75: + cflag |= DZ_B75; + break; + case 110: + cflag |= DZ_B110; + break; + case 134: + cflag |= DZ_B134; + break; + case 150: + cflag |= DZ_B150; + break; + case 300: + cflag |= DZ_B300; + break; + case 600: + cflag |= DZ_B600; + break; + case 1200: + cflag |= DZ_B1200; + break; + case 1800: + cflag |= DZ_B1800; + break; + case 2000: + cflag |= DZ_B2000; + break; + case 2400: + cflag |= DZ_B2400; + break; + case 3600: + cflag |= DZ_B3600; + break; + case 4800: + cflag |= DZ_B4800; + break; + case 7200: + cflag |= DZ_B7200; + break; + case 9600: + default: + cflag |= DZ_B9600; + } + + if (termios->c_cflag & CREAD) + cflag |= DZ_RXENAB; + + spin_lock_irqsave(&dport->port.lock, flags); + + dz_out(dport, DZ_LPR, cflag); + dport->cflag = cflag; + + /* setup accept flag */ + dport->port.read_status_mask = DZ_OERR; + if (termios->c_iflag & INPCK) + dport->port.read_status_mask |= DZ_FERR | DZ_PERR; + + /* characters to ignore */ + uport->ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR; + + spin_unlock_irqrestore(&dport->port.lock, flags); +} + +static const char *dz_type(struct uart_port *port) +{ + return "DZ"; +} + +static void dz_release_port(struct uart_port *port) +{ + /* nothing to do */ +} + +static int dz_request_port(struct uart_port *port) +{ + return 0; +} + +static void dz_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) + port->type = PORT_DZ; +} + +/* + * verify the new serial_struct (for TIOCSSERIAL). + */ +static int dz_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + int ret = 0; + if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ) + ret = -EINVAL; + if (ser->irq != port->irq) + ret = -EINVAL; + return ret; +} + +static struct uart_ops dz_ops = { + .tx_empty = dz_tx_empty, + .get_mctrl = dz_get_mctrl, + .set_mctrl = dz_set_mctrl, + .stop_tx = dz_stop_tx, + .start_tx = dz_start_tx, + .stop_rx = dz_stop_rx, + .enable_ms = dz_enable_ms, + .break_ctl = dz_break_ctl, + .startup = dz_startup, + .shutdown = dz_shutdown, + .set_termios = dz_set_termios, + .type = dz_type, + .release_port = dz_release_port, + .request_port = dz_request_port, + .config_port = dz_config_port, + .verify_port = dz_verify_port, +}; + +static void __init dz_init_ports(void) +{ + static int first = 1; + struct dz_port *dport; + unsigned long base; + int i; + + if (!first) + return; + first = 0; + + if (mips_machtype == MACH_DS23100 || + mips_machtype == MACH_DS5100) + base = (unsigned long) KN01_DZ11_BASE; + else + base = (unsigned long) KN02_DZ11_BASE; + + for (i = 0, dport = dz_ports; i < DZ_NB_PORT; i++, dport++) { + spin_lock_init(&dport->port.lock); + dport->port.membase = (char *) base; + dport->port.iotype = SERIAL_IO_PORT; + dport->port.irq = dec_interrupt[DEC_IRQ_DZ11]; + dport->port.line = i; + dport->port.fifosize = 1; + dport->port.ops = &dz_ops; + dport->port.flags = UPF_BOOT_AUTOCONF; + } +} + +static void dz_reset(struct dz_port *dport) +{ + dz_out(dport, DZ_CSR, DZ_CLR); + + while (dz_in(dport, DZ_CSR) & DZ_CLR); + /* FIXME: cpu_relax? */ + + iob(); + + /* enable scanning */ + dz_out(dport, DZ_CSR, DZ_MSE); +} + +#ifdef CONFIG_SERIAL_DZ_CONSOLE +static void dz_console_put_char(struct dz_port *dport, unsigned char ch) +{ + unsigned long flags; + int loops = 2500; + unsigned short tmp = ch; + /* this code sends stuff out to serial device - spinning its + wheels and waiting. */ + + spin_lock_irqsave(&dport->port.lock, flags); + + /* spin our wheels */ + while (((dz_in(dport, DZ_CSR) & DZ_TRDY) != DZ_TRDY) && loops--) + /* FIXME: cpu_relax, udelay? --rmk */ + ; + + /* Actually transmit the character. */ + dz_out(dport, DZ_TDR, tmp); + + spin_unlock_irqrestore(&dport->port.lock, flags); +} +/* + * ------------------------------------------------------------------- + * dz_console_print () + * + * dz_console_print is registered for printk. + * The console must be locked when we get here. + * ------------------------------------------------------------------- + */ +static void dz_console_print(struct console *cons, + const char *str, + unsigned int count) +{ + struct dz_port *dport = &dz_ports[CONSOLE_LINE]; +#ifdef DEBUG_DZ + prom_printf((char *) str); +#endif + while (count--) { + if (*str == '\n') + dz_console_put_char(dport, '\r'); + dz_console_put_char(dport, *str++); + } +} + +static int __init dz_console_setup(struct console *co, char *options) +{ + struct dz_port *dport = &dz_ports[CONSOLE_LINE]; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + int ret; + unsigned short mask, tmp; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + dz_reset(dport); + + ret = uart_set_options(&dport->port, co, baud, parity, bits, flow); + if (ret == 0) { + mask = 1 << dport->port.line; + tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ + if (!(tmp & mask)) { + tmp |= mask; /* set the TX flag */ + dz_out(dport, DZ_TCR, tmp); + } + } + + return ret; +} + +static struct console dz_sercons = +{ + .name = "ttyS", + .write = dz_console_print, + .device = uart_console_device, + .setup = dz_console_setup, + .flags = CON_CONSDEV | CON_PRINTBUFFER, + .index = CONSOLE_LINE, +}; + +void __init dz_serial_console_init(void) +{ + dz_init_ports(); + + register_console(&dz_sercons); +} + +#define SERIAL_DZ_CONSOLE &dz_sercons +#else +#define SERIAL_DZ_CONSOLE NULL +#endif /* CONFIG_SERIAL_DZ_CONSOLE */ + +static struct uart_driver dz_reg = { + .owner = THIS_MODULE, + .driver_name = "serial", +#ifdef CONFIG_DEVFS + .dev_name = "tts/%d", +#else + .dev_name = "ttyS%d", +#endif + .major = TTY_MAJOR, + .minor = 64, + .nr = DZ_NB_PORT, + .cons = SERIAL_DZ_CONSOLE, +}; + +int __init dz_init(void) +{ + unsigned long flags; + int ret, i; + + printk("%s%s\n", dz_name, dz_version); + + dz_init_ports(); + + save_flags(flags); + cli(); + +#ifndef CONFIG_SERIAL_DZ_CONSOLE + /* reset the chip */ + dz_reset(&dz_ports[0]); +#endif + + /* order matters here... the trick is that flags + is updated... in request_irq - to immediatedly obliterate + it is unwise. */ + restore_flags(flags); + + if (request_irq(dz_ports[0].port.irq, dz_interrupt, + SA_INTERRUPT, "DZ", &dz_ports[0])) + panic("Unable to register DZ interrupt"); + + ret = uart_register_driver(&dz_reg); + if (ret != 0) + return ret; + + for (i = 0; i < DZ_NB_PORT; i++) + uart_add_one_port(&dz_reg, &dz_ports[i].port); + + return ret; +} + +MODULE_DESCRIPTION("DECstation DZ serial driver"); +MODULE_LICENSE("GPL"); |