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-rw-r--r--drivers/tty/serial/dz.c945
1 files changed, 945 insertions, 0 deletions
diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
new file mode 100644
index 000000000..4552742c3
--- /dev/null
+++ b/drivers/tty/serial/dz.c
@@ -0,0 +1,945 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * dz.c: Serial port driver for DECstations equipped
+ * with the DZ chipset.
+ *
+ * Copyright (C) 1998 Olivier A. D. Lebaillif
+ *
+ * Email: olivier.lebaillif@ifrsys.com
+ *
+ * Copyright (C) 2004, 2006, 2007 Maciej W. Rozycki
+ *
+ * [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/bitops.h>
+#include <linux/compiler.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/module.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/sysrq.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+
+#include <linux/atomic.h>
+#include <asm/bootinfo.h>
+#include <asm/io.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/dec/system.h>
+
+#include "dz.h"
+
+
+MODULE_DESCRIPTION("DECstation DZ serial driver");
+MODULE_LICENSE("GPL");
+
+
+static char dz_name[] __initdata = "DECstation DZ serial driver version ";
+static char dz_version[] __initdata = "1.04";
+
+struct dz_port {
+ struct dz_mux *mux;
+ struct uart_port port;
+ unsigned int cflag;
+};
+
+struct dz_mux {
+ struct dz_port dport[DZ_NB_PORT];
+ atomic_t map_guard;
+ atomic_t irq_guard;
+ int initialised;
+};
+
+static struct dz_mux dz_mux;
+
+static inline struct dz_port *to_dport(struct uart_port *uport)
+{
+ return container_of(uport, struct dz_port, port);
+}
+
+/*
+ * ------------------------------------------------------------
+ * dz_in () and dz_out ()
+ *
+ * These routines are used to access the registers of the DZ
+ * chip, hiding relocation differences between implementation.
+ * ------------------------------------------------------------
+ */
+
+static u16 dz_in(struct dz_port *dport, unsigned offset)
+{
+ void __iomem *addr = dport->port.membase + offset;
+
+ return readw(addr);
+}
+
+static void dz_out(struct dz_port *dport, unsigned offset, u16 value)
+{
+ void __iomem *addr = dport->port.membase + offset;
+
+ writew(value, addr);
+}
+
+/*
+ * ------------------------------------------------------------
+ * 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)
+{
+ struct dz_port *dport = to_dport(uport);
+ u16 tmp, mask = 1 << dport->port.line;
+
+ tmp = dz_in(dport, DZ_TCR); /* read the TX flag */
+ tmp &= ~mask; /* clear the TX flag */
+ dz_out(dport, DZ_TCR, tmp);
+}
+
+static void dz_start_tx(struct uart_port *uport)
+{
+ struct dz_port *dport = to_dport(uport);
+ u16 tmp, mask = 1 << dport->port.line;
+
+ tmp = dz_in(dport, DZ_TCR); /* read the TX flag */
+ tmp |= mask; /* set the TX flag */
+ dz_out(dport, DZ_TCR, tmp);
+}
+
+static void dz_stop_rx(struct uart_port *uport)
+{
+ struct dz_port *dport = to_dport(uport);
+
+ dport->cflag &= ~DZ_RXENAB;
+ dz_out(dport, DZ_LPR, dport->cflag);
+}
+
+/*
+ * ------------------------------------------------------------
+ *
+ * Here start 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: dz_interrupt() is a "fast" interrupt, which means that it
+ * runs with interrupts turned off. People who may want to modify
+ * dz_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_mux *mux)
+{
+ struct uart_port *uport;
+ struct dz_port *dport = &mux->dport[0];
+ struct uart_icount *icount;
+ int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
+ unsigned char ch, flag;
+ u16 status;
+ int i;
+
+ while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) {
+ dport = &mux->dport[LINE(status)];
+ uport = &dport->port;
+
+ ch = UCHAR(status); /* grab the char */
+ flag = TTY_NORMAL;
+
+ icount = &uport->icount;
+ icount->rx++;
+
+ if (unlikely(status & (DZ_OERR | DZ_FERR | DZ_PERR))) {
+
+ /*
+ * There is no separate BREAK status bit, so treat
+ * null characters with framing errors as BREAKs;
+ * normally, otherwise. For this move the Framing
+ * Error bit to a simulated BREAK bit.
+ */
+ if (!ch) {
+ status |= (status & DZ_FERR) >>
+ (ffs(DZ_FERR) - ffs(DZ_BREAK));
+ status &= ~DZ_FERR;
+ }
+
+ /* Handle SysRq/SAK & keep track of the statistics. */
+ if (status & DZ_BREAK) {
+ icount->brk++;
+ if (uart_handle_break(uport))
+ continue;
+ } else if (status & DZ_FERR)
+ icount->frame++;
+ else if (status & DZ_PERR)
+ icount->parity++;
+ if (status & DZ_OERR)
+ icount->overrun++;
+
+ status &= uport->read_status_mask;
+ if (status & DZ_BREAK)
+ flag = TTY_BREAK;
+ else if (status & DZ_FERR)
+ flag = TTY_FRAME;
+ else if (status & DZ_PERR)
+ flag = TTY_PARITY;
+
+ }
+
+ if (uart_handle_sysrq_char(uport, ch))
+ continue;
+
+ uart_insert_char(uport, status, DZ_OERR, ch, flag);
+ lines_rx[LINE(status)] = 1;
+ }
+ for (i = 0; i < DZ_NB_PORT; i++)
+ if (lines_rx[i])
+ tty_flip_buffer_push(&mux->dport[i].port.state->port);
+}
+
+/*
+ * ------------------------------------------------------------
+ * transmit_char ()
+ *
+ * This routine deals with outputs to any lines.
+ * ------------------------------------------------------------
+ */
+static inline void dz_transmit_chars(struct dz_mux *mux)
+{
+ struct dz_port *dport = &mux->dport[0];
+ struct circ_buf *xmit;
+ unsigned char tmp;
+ u16 status;
+
+ status = dz_in(dport, DZ_CSR);
+ dport = &mux->dport[LINE(status)];
+ xmit = &dport->port.state->xmit;
+
+ 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)) {
+ spin_lock(&dport->port.lock);
+ dz_stop_tx(&dport->port);
+ spin_unlock(&dport->port.lock);
+ return;
+ }
+
+ /*
+ * If something to do... (remember 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 are done. */
+ if (uart_circ_empty(xmit)) {
+ spin_lock(&dport->port.lock);
+ dz_stop_tx(&dport->port);
+ spin_unlock(&dport->port.lock);
+ }
+}
+
+/*
+ * ------------------------------------------------------------
+ * check_modem_status()
+ *
+ * DS 3100 & 5100: Only valid for the MODEM line, duh!
+ * DS 5000/200: Valid for the MODEM and PRINTER line.
+ * ------------------------------------------------------------
+ */
+static inline void check_modem_status(struct dz_port *dport)
+{
+ /*
+ * FIXME:
+ * 1. No status change interrupt; use a timer.
+ * 2. Handle the 3100/5000 as appropriate. --macro
+ */
+ u16 status;
+
+ /* If not the 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_id)
+{
+ struct dz_mux *mux = dev_id;
+ struct dz_port *dport = &mux->dport[0];
+ u16 status;
+
+ /* get the reason why we just got an irq */
+ status = dz_in(dport, DZ_CSR);
+
+ if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
+ dz_receive_chars(mux);
+
+ if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
+ dz_transmit_chars(mux);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * -------------------------------------------------------------------
+ * Here ends the DZ interrupt routines.
+ * -------------------------------------------------------------------
+ */
+
+static unsigned int dz_get_mctrl(struct uart_port *uport)
+{
+ /*
+ * FIXME: Handle the 3100/5000 as appropriate. --macro
+ */
+ struct dz_port *dport = to_dport(uport);
+ unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
+
+ if (dport->port.line == DZ_MODEM) {
+ 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)
+{
+ /*
+ * FIXME: Handle the 3100/5000 as appropriate. --macro
+ */
+ struct dz_port *dport = to_dport(uport);
+ u16 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 = to_dport(uport);
+ struct dz_mux *mux = dport->mux;
+ unsigned long flags;
+ int irq_guard;
+ int ret;
+ u16 tmp;
+
+ irq_guard = atomic_add_return(1, &mux->irq_guard);
+ if (irq_guard != 1)
+ return 0;
+
+ ret = request_irq(dport->port.irq, dz_interrupt,
+ IRQF_SHARED, "dz", mux);
+ if (ret) {
+ atomic_add(-1, &mux->irq_guard);
+ printk(KERN_ERR "dz: Cannot get IRQ %d!\n", dport->port.irq);
+ return ret;
+ }
+
+ spin_lock_irqsave(&dport->port.lock, flags);
+
+ /* Enable interrupts. */
+ tmp = dz_in(dport, DZ_CSR);
+ tmp |= DZ_RIE | DZ_TIE;
+ 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)
+{
+ struct dz_port *dport = to_dport(uport);
+ struct dz_mux *mux = dport->mux;
+ unsigned long flags;
+ int irq_guard;
+ u16 tmp;
+
+ spin_lock_irqsave(&dport->port.lock, flags);
+ dz_stop_tx(&dport->port);
+ spin_unlock_irqrestore(&dport->port.lock, flags);
+
+ irq_guard = atomic_add_return(-1, &mux->irq_guard);
+ if (!irq_guard) {
+ /* Disable interrupts. */
+ tmp = dz_in(dport, DZ_CSR);
+ tmp &= ~(DZ_RIE | DZ_TIE);
+ dz_out(dport, DZ_CSR, tmp);
+
+ free_irq(dport->port.irq, mux);
+ }
+}
+
+/*
+ * -------------------------------------------------------------------
+ * dz_tx_empty() -- get the transmitter empty status
+ *
+ * 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 = to_dport(uport);
+ unsigned short tmp, mask = 1 << dport->port.line;
+
+ tmp = dz_in(dport, DZ_TCR);
+ tmp &= mask;
+
+ return tmp ? 0 : TIOCSER_TEMT;
+}
+
+static void dz_break_ctl(struct uart_port *uport, int break_state)
+{
+ /*
+ * FIXME: Can't access BREAK bits in TDR easily;
+ * reuse the code for polled TX. --macro
+ */
+ struct dz_port *dport = to_dport(uport);
+ unsigned long flags;
+ unsigned short tmp, mask = 1 << dport->port.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 int dz_encode_baud_rate(unsigned int baud)
+{
+ switch (baud) {
+ case 50:
+ return DZ_B50;
+ case 75:
+ return DZ_B75;
+ case 110:
+ return DZ_B110;
+ case 134:
+ return DZ_B134;
+ case 150:
+ return DZ_B150;
+ case 300:
+ return DZ_B300;
+ case 600:
+ return DZ_B600;
+ case 1200:
+ return DZ_B1200;
+ case 1800:
+ return DZ_B1800;
+ case 2000:
+ return DZ_B2000;
+ case 2400:
+ return DZ_B2400;
+ case 3600:
+ return DZ_B3600;
+ case 4800:
+ return DZ_B4800;
+ case 7200:
+ return DZ_B7200;
+ case 9600:
+ return DZ_B9600;
+ default:
+ return -1;
+ }
+}
+
+
+static void dz_reset(struct dz_port *dport)
+{
+ struct dz_mux *mux = dport->mux;
+
+ if (mux->initialised)
+ return;
+
+ dz_out(dport, DZ_CSR, DZ_CLR);
+ while (dz_in(dport, DZ_CSR) & DZ_CLR);
+ iob();
+
+ /* Enable scanning. */
+ dz_out(dport, DZ_CSR, DZ_MSE);
+
+ mux->initialised = 1;
+}
+
+static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
+ struct ktermios *old_termios)
+{
+ struct dz_port *dport = to_dport(uport);
+ unsigned long flags;
+ unsigned int cflag, baud;
+ int bflag;
+
+ 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);
+ bflag = dz_encode_baud_rate(baud);
+ if (bflag < 0) { /* Try to keep unchanged. */
+ baud = uart_get_baud_rate(uport, old_termios, NULL, 50, 9600);
+ bflag = dz_encode_baud_rate(baud);
+ if (bflag < 0) { /* Resort to 9600. */
+ baud = 9600;
+ bflag = DZ_B9600;
+ }
+ tty_termios_encode_baud_rate(termios, baud, baud);
+ }
+ cflag |= bflag;
+
+ if (termios->c_cflag & CREAD)
+ cflag |= DZ_RXENAB;
+
+ spin_lock_irqsave(&dport->port.lock, flags);
+
+ uart_update_timeout(uport, termios->c_cflag, baud);
+
+ 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;
+ if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
+ dport->port.read_status_mask |= DZ_BREAK;
+
+ /* characters to ignore */
+ uport->ignore_status_mask = 0;
+ if ((termios->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
+ dport->port.ignore_status_mask |= DZ_OERR;
+ if (termios->c_iflag & IGNPAR)
+ dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR;
+ if (termios->c_iflag & IGNBRK)
+ dport->port.ignore_status_mask |= DZ_BREAK;
+
+ spin_unlock_irqrestore(&dport->port.lock, flags);
+}
+
+/*
+ * Hack alert!
+ * Required solely so that the initial PROM-based console
+ * works undisturbed in parallel with this one.
+ */
+static void dz_pm(struct uart_port *uport, unsigned int state,
+ unsigned int oldstate)
+{
+ struct dz_port *dport = to_dport(uport);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dport->port.lock, flags);
+ if (state < 3)
+ dz_start_tx(&dport->port);
+ else
+ dz_stop_tx(&dport->port);
+ spin_unlock_irqrestore(&dport->port.lock, flags);
+}
+
+
+static const char *dz_type(struct uart_port *uport)
+{
+ return "DZ";
+}
+
+static void dz_release_port(struct uart_port *uport)
+{
+ struct dz_mux *mux = to_dport(uport)->mux;
+ int map_guard;
+
+ iounmap(uport->membase);
+ uport->membase = NULL;
+
+ map_guard = atomic_add_return(-1, &mux->map_guard);
+ if (!map_guard)
+ release_mem_region(uport->mapbase, dec_kn_slot_size);
+}
+
+static int dz_map_port(struct uart_port *uport)
+{
+ if (!uport->membase)
+ uport->membase = ioremap(uport->mapbase,
+ dec_kn_slot_size);
+ if (!uport->membase) {
+ printk(KERN_ERR "dz: Cannot map MMIO\n");
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static int dz_request_port(struct uart_port *uport)
+{
+ struct dz_mux *mux = to_dport(uport)->mux;
+ int map_guard;
+ int ret;
+
+ map_guard = atomic_add_return(1, &mux->map_guard);
+ if (map_guard == 1) {
+ if (!request_mem_region(uport->mapbase, dec_kn_slot_size,
+ "dz")) {
+ atomic_add(-1, &mux->map_guard);
+ printk(KERN_ERR
+ "dz: Unable to reserve MMIO resource\n");
+ return -EBUSY;
+ }
+ }
+ ret = dz_map_port(uport);
+ if (ret) {
+ map_guard = atomic_add_return(-1, &mux->map_guard);
+ if (!map_guard)
+ release_mem_region(uport->mapbase, dec_kn_slot_size);
+ return ret;
+ }
+ return 0;
+}
+
+static void dz_config_port(struct uart_port *uport, int flags)
+{
+ struct dz_port *dport = to_dport(uport);
+
+ if (flags & UART_CONFIG_TYPE) {
+ if (dz_request_port(uport))
+ return;
+
+ uport->type = PORT_DZ;
+
+ dz_reset(dport);
+ }
+}
+
+/*
+ * Verify the new serial_struct (for TIOCSSERIAL).
+ */
+static int dz_verify_port(struct uart_port *uport, struct serial_struct *ser)
+{
+ int ret = 0;
+
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ)
+ ret = -EINVAL;
+ if (ser->irq != uport->irq)
+ ret = -EINVAL;
+ return ret;
+}
+
+static const 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,
+ .break_ctl = dz_break_ctl,
+ .startup = dz_startup,
+ .shutdown = dz_shutdown,
+ .set_termios = dz_set_termios,
+ .pm = dz_pm,
+ .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;
+ unsigned long base;
+ int line;
+
+ if (!first)
+ return;
+ first = 0;
+
+ if (mips_machtype == MACH_DS23100 || mips_machtype == MACH_DS5100)
+ base = dec_kn_slot_base + KN01_DZ11;
+ else
+ base = dec_kn_slot_base + KN02_DZ11;
+
+ for (line = 0; line < DZ_NB_PORT; line++) {
+ struct dz_port *dport = &dz_mux.dport[line];
+ struct uart_port *uport = &dport->port;
+
+ dport->mux = &dz_mux;
+
+ uport->irq = dec_interrupt[DEC_IRQ_DZ11];
+ uport->fifosize = 1;
+ uport->iotype = UPIO_MEM;
+ uport->flags = UPF_BOOT_AUTOCONF;
+ uport->ops = &dz_ops;
+ uport->line = line;
+ uport->mapbase = base;
+ uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_DZ_CONSOLE);
+ }
+}
+
+#ifdef CONFIG_SERIAL_DZ_CONSOLE
+/*
+ * -------------------------------------------------------------------
+ * dz_console_putchar() -- transmit a character
+ *
+ * Polled transmission. This is tricky. We need to mask transmit
+ * interrupts so that they do not interfere, enable the transmitter
+ * for the line requested and then wait till the transmit scanner
+ * requests data for this line. But it may request data for another
+ * line first, in which case we have to disable its transmitter and
+ * repeat waiting till our line pops up. Only then the character may
+ * be transmitted. Finally, the state of the transmitter mask is
+ * restored. Welcome to the world of PDP-11!
+ * -------------------------------------------------------------------
+ */
+static void dz_console_putchar(struct uart_port *uport, int ch)
+{
+ struct dz_port *dport = to_dport(uport);
+ unsigned long flags;
+ unsigned short csr, tcr, trdy, mask;
+ int loops = 10000;
+
+ spin_lock_irqsave(&dport->port.lock, flags);
+ csr = dz_in(dport, DZ_CSR);
+ dz_out(dport, DZ_CSR, csr & ~DZ_TIE);
+ tcr = dz_in(dport, DZ_TCR);
+ tcr |= 1 << dport->port.line;
+ mask = tcr;
+ dz_out(dport, DZ_TCR, mask);
+ iob();
+ spin_unlock_irqrestore(&dport->port.lock, flags);
+
+ do {
+ trdy = dz_in(dport, DZ_CSR);
+ if (!(trdy & DZ_TRDY))
+ continue;
+ trdy = (trdy & DZ_TLINE) >> 8;
+ if (trdy == dport->port.line)
+ break;
+ mask &= ~(1 << trdy);
+ dz_out(dport, DZ_TCR, mask);
+ iob();
+ udelay(2);
+ } while (--loops);
+
+ if (loops) /* Cannot send otherwise. */
+ dz_out(dport, DZ_TDR, ch);
+
+ dz_out(dport, DZ_TCR, tcr);
+ dz_out(dport, DZ_CSR, csr);
+}
+
+/*
+ * -------------------------------------------------------------------
+ * 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 *co,
+ const char *str,
+ unsigned int count)
+{
+ struct dz_port *dport = &dz_mux.dport[co->index];
+#ifdef DEBUG_DZ
+ prom_printf((char *) str);
+#endif
+ uart_console_write(&dport->port, str, count, dz_console_putchar);
+}
+
+static int __init dz_console_setup(struct console *co, char *options)
+{
+ struct dz_port *dport = &dz_mux.dport[co->index];
+ struct uart_port *uport = &dport->port;
+ int baud = 9600;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+ int ret;
+
+ ret = dz_map_port(uport);
+ if (ret)
+ return ret;
+
+ spin_lock_init(&dport->port.lock); /* For dz_pm(). */
+
+ dz_reset(dport);
+ dz_pm(uport, 0, -1);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(&dport->port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver dz_reg;
+static struct console dz_console = {
+ .name = "ttyS",
+ .write = dz_console_print,
+ .device = uart_console_device,
+ .setup = dz_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &dz_reg,
+};
+
+static int __init dz_serial_console_init(void)
+{
+ if (!IOASIC) {
+ dz_init_ports();
+ register_console(&dz_console);
+ return 0;
+ } else
+ return -ENXIO;
+}
+
+console_initcall(dz_serial_console_init);
+
+#define SERIAL_DZ_CONSOLE &dz_console
+#else
+#define SERIAL_DZ_CONSOLE NULL
+#endif /* CONFIG_SERIAL_DZ_CONSOLE */
+
+static struct uart_driver dz_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "serial",
+ .dev_name = "ttyS",
+ .major = TTY_MAJOR,
+ .minor = 64,
+ .nr = DZ_NB_PORT,
+ .cons = SERIAL_DZ_CONSOLE,
+};
+
+static int __init dz_init(void)
+{
+ int ret, i;
+
+ if (IOASIC)
+ return -ENXIO;
+
+ printk("%s%s\n", dz_name, dz_version);
+
+ dz_init_ports();
+
+ ret = uart_register_driver(&dz_reg);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < DZ_NB_PORT; i++)
+ uart_add_one_port(&dz_reg, &dz_mux.dport[i].port);
+
+ return 0;
+}
+
+module_init(dz_init);