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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/serial/au1x00_uart.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/serial/au1x00_uart.c')
-rw-r--r--drivers/serial/au1x00_uart.c1312
1 files changed, 1312 insertions, 0 deletions
diff --git a/drivers/serial/au1x00_uart.c b/drivers/serial/au1x00_uart.c
new file mode 100644
index 000000000000..b6d3d5034940
--- /dev/null
+++ b/drivers/serial/au1x00_uart.c
@@ -0,0 +1,1312 @@
+/*
+ * Driver for 8250/16550-type serial ports
+ *
+ * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ *
+ * Copyright (C) 2001 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * A note about mapbase / membase
+ *
+ * mapbase is the physical address of the IO port. Currently, we don't
+ * support this very well, and it may well be dropped from this driver
+ * in future. As such, mapbase should be NULL.
+ *
+ * membase is an 'ioremapped' cookie. This is compatible with the old
+ * serial.c driver, and is currently the preferred form.
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/serial.h>
+#include <linux/serialP.h>
+#include <linux/delay.h>
+
+#include <asm/serial.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/mach-au1x00/au1000.h>
+
+#if defined(CONFIG_SERIAL_AU1X00_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+#include "8250.h"
+
+/*
+ * Debugging.
+ */
+#if 0
+#define DEBUG_AUTOCONF(fmt...) printk(fmt)
+#else
+#define DEBUG_AUTOCONF(fmt...) do { } while (0)
+#endif
+
+#if 0
+#define DEBUG_INTR(fmt...) printk(fmt)
+#else
+#define DEBUG_INTR(fmt...) do { } while (0)
+#endif
+
+#define PASS_LIMIT 256
+
+/*
+ * We default to IRQ0 for the "no irq" hack. Some
+ * machine types want others as well - they're free
+ * to redefine this in their header file.
+ */
+#define is_real_interrupt(irq) ((irq) != 0)
+
+static struct old_serial_port old_serial_port[] = {
+ { .baud_base = 0,
+ .iomem_base = (u8 *)UART0_ADDR,
+ .irq = AU1000_UART0_INT,
+ .flags = STD_COM_FLAGS,
+ .iomem_reg_shift = 2,
+ }, {
+ .baud_base = 0,
+ .iomem_base = (u8 *)UART1_ADDR,
+ .irq = AU1000_UART1_INT,
+ .flags = STD_COM_FLAGS,
+ .iomem_reg_shift = 2
+ }, {
+ .baud_base = 0,
+ .iomem_base = (u8 *)UART2_ADDR,
+ .irq = AU1000_UART2_INT,
+ .flags = STD_COM_FLAGS,
+ .iomem_reg_shift = 2
+ }, {
+ .baud_base = 0,
+ .iomem_base = (u8 *)UART3_ADDR,
+ .irq = AU1000_UART3_INT,
+ .flags = STD_COM_FLAGS,
+ .iomem_reg_shift = 2
+ }
+};
+
+#define UART_NR ARRAY_SIZE(old_serial_port)
+
+struct uart_8250_port {
+ struct uart_port port;
+ struct timer_list timer; /* "no irq" timer */
+ struct list_head list; /* ports on this IRQ */
+ unsigned short rev;
+ unsigned char acr;
+ unsigned char ier;
+ unsigned char lcr;
+ unsigned char mcr_mask; /* mask of user bits */
+ unsigned char mcr_force; /* mask of forced bits */
+ unsigned char lsr_break_flag;
+
+ /*
+ * We provide a per-port pm hook.
+ */
+ void (*pm)(struct uart_port *port,
+ unsigned int state, unsigned int old);
+};
+
+struct irq_info {
+ spinlock_t lock;
+ struct list_head *head;
+};
+
+static struct irq_info irq_lists[NR_IRQS];
+
+/*
+ * Here we define the default xmit fifo size used for each type of UART.
+ */
+static const struct serial_uart_config uart_config[PORT_MAX_8250+1] = {
+ { "unknown", 1, 0 },
+ { "8250", 1, 0 },
+ { "16450", 1, 0 },
+ { "16550", 1, 0 },
+ /* PORT_16550A */
+ { "AU1X00_UART",16, UART_CLEAR_FIFO | UART_USE_FIFO },
+};
+
+static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
+{
+ return au_readl((unsigned long)up->port.membase + offset);
+}
+
+static _INLINE_ void
+serial_out(struct uart_8250_port *up, int offset, int value)
+{
+ au_writel(value, (unsigned long)up->port.membase + offset);
+}
+
+#define serial_inp(up, offset) serial_in(up, offset)
+#define serial_outp(up, offset, value) serial_out(up, offset, value)
+
+/*
+ * This routine is called by rs_init() to initialize a specific serial
+ * port. It determines what type of UART chip this serial port is
+ * using: 8250, 16450, 16550, 16550A. The important question is
+ * whether or not this UART is a 16550A or not, since this will
+ * determine whether or not we can use its FIFO features or not.
+ */
+static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
+{
+ unsigned char save_lcr, save_mcr;
+ unsigned long flags;
+
+ if (!up->port.iobase && !up->port.mapbase && !up->port.membase)
+ return;
+
+ DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%08lx): ",
+ up->port.line, up->port.iobase, up->port.membase);
+
+ /*
+ * We really do need global IRQs disabled here - we're going to
+ * be frobbing the chips IRQ enable register to see if it exists.
+ */
+ spin_lock_irqsave(&up->port.lock, flags);
+// save_flags(flags); cli();
+
+ save_mcr = serial_in(up, UART_MCR);
+ save_lcr = serial_in(up, UART_LCR);
+
+ up->port.type = PORT_16550A;
+ serial_outp(up, UART_LCR, save_lcr);
+
+ up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
+
+ if (up->port.type == PORT_UNKNOWN)
+ goto out;
+
+ /*
+ * Reset the UART.
+ */
+ serial_outp(up, UART_MCR, save_mcr);
+ serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR |
+ UART_FCR_CLEAR_XMIT));
+ serial_outp(up, UART_FCR, 0);
+ (void)serial_in(up, UART_RX);
+ serial_outp(up, UART_IER, 0);
+
+ out:
+ spin_unlock_irqrestore(&up->port.lock, flags);
+// restore_flags(flags);
+ DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name);
+}
+
+static void serial8250_stop_tx(struct uart_port *port, unsigned int tty_stop)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ if (up->ier & UART_IER_THRI) {
+ up->ier &= ~UART_IER_THRI;
+ serial_out(up, UART_IER, up->ier);
+ }
+}
+
+static void serial8250_start_tx(struct uart_port *port, unsigned int tty_start)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ if (!(up->ier & UART_IER_THRI)) {
+ up->ier |= UART_IER_THRI;
+ serial_out(up, UART_IER, up->ier);
+ }
+}
+
+static void serial8250_stop_rx(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ up->ier &= ~UART_IER_RLSI;
+ up->port.read_status_mask &= ~UART_LSR_DR;
+ serial_out(up, UART_IER, up->ier);
+}
+
+static void serial8250_enable_ms(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ up->ier |= UART_IER_MSI;
+ serial_out(up, UART_IER, up->ier);
+}
+
+static _INLINE_ void
+receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs)
+{
+ struct tty_struct *tty = up->port.info->tty;
+ unsigned char ch;
+ int max_count = 256;
+
+ do {
+ if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
+ tty->flip.work.func((void *)tty);
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+ return; // if TTY_DONT_FLIP is set
+ }
+ ch = serial_inp(up, UART_RX);
+ *tty->flip.char_buf_ptr = ch;
+ *tty->flip.flag_buf_ptr = TTY_NORMAL;
+ up->port.icount.rx++;
+
+ if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
+ UART_LSR_FE | UART_LSR_OE))) {
+ /*
+ * For statistics only
+ */
+ if (*status & UART_LSR_BI) {
+ *status &= ~(UART_LSR_FE | UART_LSR_PE);
+ up->port.icount.brk++;
+ /*
+ * We do the SysRQ and SAK checking
+ * here because otherwise the break
+ * may get masked by ignore_status_mask
+ * or read_status_mask.
+ */
+ if (uart_handle_break(&up->port))
+ goto ignore_char;
+ } else if (*status & UART_LSR_PE)
+ up->port.icount.parity++;
+ else if (*status & UART_LSR_FE)
+ up->port.icount.frame++;
+ if (*status & UART_LSR_OE)
+ up->port.icount.overrun++;
+
+ /*
+ * Mask off conditions which should be ingored.
+ */
+ *status &= up->port.read_status_mask;
+
+#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
+ if (up->port.line == up->port.cons->index) {
+ /* Recover the break flag from console xmit */
+ *status |= up->lsr_break_flag;
+ up->lsr_break_flag = 0;
+ }
+#endif
+ if (*status & UART_LSR_BI) {
+ DEBUG_INTR("handling break....");
+ *tty->flip.flag_buf_ptr = TTY_BREAK;
+ } else if (*status & UART_LSR_PE)
+ *tty->flip.flag_buf_ptr = TTY_PARITY;
+ else if (*status & UART_LSR_FE)
+ *tty->flip.flag_buf_ptr = TTY_FRAME;
+ }
+ if (uart_handle_sysrq_char(&up->port, ch, regs))
+ goto ignore_char;
+ if ((*status & up->port.ignore_status_mask) == 0) {
+ tty->flip.flag_buf_ptr++;
+ tty->flip.char_buf_ptr++;
+ tty->flip.count++;
+ }
+ if ((*status & UART_LSR_OE) &&
+ tty->flip.count < TTY_FLIPBUF_SIZE) {
+ /*
+ * Overrun is special, since it's reported
+ * immediately, and doesn't affect the current
+ * character.
+ */
+ *tty->flip.flag_buf_ptr = TTY_OVERRUN;
+ tty->flip.flag_buf_ptr++;
+ tty->flip.char_buf_ptr++;
+ tty->flip.count++;
+ }
+ ignore_char:
+ *status = serial_inp(up, UART_LSR);
+ } while ((*status & UART_LSR_DR) && (max_count-- > 0));
+ spin_unlock(&up->port.lock);
+ tty_flip_buffer_push(tty);
+ spin_lock(&up->port.lock);
+}
+
+static _INLINE_ void transmit_chars(struct uart_8250_port *up)
+{
+ struct circ_buf *xmit = &up->port.info->xmit;
+ int count;
+
+ if (up->port.x_char) {
+ serial_outp(up, UART_TX, up->port.x_char);
+ up->port.icount.tx++;
+ up->port.x_char = 0;
+ return;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
+ serial8250_stop_tx(&up->port, 0);
+ return;
+ }
+
+ count = up->port.fifosize;
+ do {
+ serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ up->port.icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ } while (--count > 0);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&up->port);
+
+ DEBUG_INTR("THRE...");
+
+ if (uart_circ_empty(xmit))
+ serial8250_stop_tx(&up->port, 0);
+}
+
+static _INLINE_ void check_modem_status(struct uart_8250_port *up)
+{
+ int status;
+
+ status = serial_in(up, UART_MSR);
+
+ if ((status & UART_MSR_ANY_DELTA) == 0)
+ return;
+
+ if (status & UART_MSR_TERI)
+ up->port.icount.rng++;
+ if (status & UART_MSR_DDSR)
+ up->port.icount.dsr++;
+ if (status & UART_MSR_DDCD)
+ uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
+ if (status & UART_MSR_DCTS)
+ uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
+
+ wake_up_interruptible(&up->port.info->delta_msr_wait);
+}
+
+/*
+ * This handles the interrupt from one port.
+ */
+static inline void
+serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
+{
+ unsigned int status = serial_inp(up, UART_LSR);
+
+ DEBUG_INTR("status = %x...", status);
+
+ if (status & UART_LSR_DR)
+ receive_chars(up, &status, regs);
+ check_modem_status(up);
+ if (status & UART_LSR_THRE)
+ transmit_chars(up);
+}
+
+/*
+ * This is the serial driver's interrupt routine.
+ *
+ * Arjan thinks the old way was overly complex, so it got simplified.
+ * Alan disagrees, saying that need the complexity to handle the weird
+ * nature of ISA shared interrupts. (This is a special exception.)
+ *
+ * In order to handle ISA shared interrupts properly, we need to check
+ * that all ports have been serviced, and therefore the ISA interrupt
+ * line has been de-asserted.
+ *
+ * This means we need to loop through all ports. checking that they
+ * don't have an interrupt pending.
+ */
+static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct irq_info *i = dev_id;
+ struct list_head *l, *end = NULL;
+ int pass_counter = 0;
+
+ DEBUG_INTR("serial8250_interrupt(%d)...", irq);
+
+ spin_lock(&i->lock);
+
+ l = i->head;
+ do {
+ struct uart_8250_port *up;
+ unsigned int iir;
+
+ up = list_entry(l, struct uart_8250_port, list);
+
+ iir = serial_in(up, UART_IIR);
+ if (!(iir & UART_IIR_NO_INT)) {
+ spin_lock(&up->port.lock);
+ serial8250_handle_port(up, regs);
+ spin_unlock(&up->port.lock);
+
+ end = NULL;
+ } else if (end == NULL)
+ end = l;
+
+ l = l->next;
+
+ if (l == i->head && pass_counter++ > PASS_LIMIT) {
+ /* If we hit this, we're dead. */
+ printk(KERN_ERR "serial8250: too much work for "
+ "irq%d\n", irq);
+ break;
+ }
+ } while (l != end);
+
+ spin_unlock(&i->lock);
+
+ DEBUG_INTR("end.\n");
+ /* FIXME! Was it really ours? */
+ return IRQ_HANDLED;
+}
+
+/*
+ * To support ISA shared interrupts, we need to have one interrupt
+ * handler that ensures that the IRQ line has been deasserted
+ * before returning. Failing to do this will result in the IRQ
+ * line being stuck active, and, since ISA irqs are edge triggered,
+ * no more IRQs will be seen.
+ */
+static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
+{
+ spin_lock_irq(&i->lock);
+
+ if (!list_empty(i->head)) {
+ if (i->head == &up->list)
+ i->head = i->head->next;
+ list_del(&up->list);
+ } else {
+ BUG_ON(i->head != &up->list);
+ i->head = NULL;
+ }
+
+ spin_unlock_irq(&i->lock);
+}
+
+static int serial_link_irq_chain(struct uart_8250_port *up)
+{
+ struct irq_info *i = irq_lists + up->port.irq;
+ int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
+
+ spin_lock_irq(&i->lock);
+
+ if (i->head) {
+ list_add(&up->list, i->head);
+ spin_unlock_irq(&i->lock);
+
+ ret = 0;
+ } else {
+ INIT_LIST_HEAD(&up->list);
+ i->head = &up->list;
+ spin_unlock_irq(&i->lock);
+
+ ret = request_irq(up->port.irq, serial8250_interrupt,
+ irq_flags, "serial", i);
+ if (ret < 0)
+ serial_do_unlink(i, up);
+ }
+
+ return ret;
+}
+
+static void serial_unlink_irq_chain(struct uart_8250_port *up)
+{
+ struct irq_info *i = irq_lists + up->port.irq;
+
+ BUG_ON(i->head == NULL);
+
+ if (list_empty(i->head))
+ free_irq(up->port.irq, i);
+
+ serial_do_unlink(i, up);
+}
+
+/*
+ * This function is used to handle ports that do not have an
+ * interrupt. This doesn't work very well for 16450's, but gives
+ * barely passable results for a 16550A. (Although at the expense
+ * of much CPU overhead).
+ */
+static void serial8250_timeout(unsigned long data)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)data;
+ unsigned int timeout;
+ unsigned int iir;
+
+ iir = serial_in(up, UART_IIR);
+ if (!(iir & UART_IIR_NO_INT)) {
+ spin_lock(&up->port.lock);
+ serial8250_handle_port(up, NULL);
+ spin_unlock(&up->port.lock);
+ }
+
+ timeout = up->port.timeout;
+ timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
+ mod_timer(&up->timer, jiffies + timeout);
+}
+
+static unsigned int serial8250_tx_empty(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+ unsigned int ret;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ return ret;
+}
+
+static unsigned int serial8250_get_mctrl(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+ unsigned char status;
+ unsigned int ret;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ status = serial_in(up, UART_MSR);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ ret = 0;
+ if (status & UART_MSR_DCD)
+ ret |= TIOCM_CAR;
+ if (status & UART_MSR_RI)
+ ret |= TIOCM_RNG;
+ if (status & UART_MSR_DSR)
+ ret |= TIOCM_DSR;
+ if (status & UART_MSR_CTS)
+ ret |= TIOCM_CTS;
+ return ret;
+}
+
+static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned char mcr = 0;
+
+ if (mctrl & TIOCM_RTS)
+ mcr |= UART_MCR_RTS;
+ if (mctrl & TIOCM_DTR)
+ mcr |= UART_MCR_DTR;
+ if (mctrl & TIOCM_OUT1)
+ mcr |= UART_MCR_OUT1;
+ if (mctrl & TIOCM_OUT2)
+ mcr |= UART_MCR_OUT2;
+ if (mctrl & TIOCM_LOOP)
+ mcr |= UART_MCR_LOOP;
+
+ mcr = (mcr & up->mcr_mask) | up->mcr_force;
+
+ serial_out(up, UART_MCR, mcr);
+}
+
+static void serial8250_break_ctl(struct uart_port *port, int break_state)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (break_state == -1)
+ up->lcr |= UART_LCR_SBC;
+ else
+ up->lcr &= ~UART_LCR_SBC;
+ serial_out(up, UART_LCR, up->lcr);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static int serial8250_startup(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+ int retval;
+
+ /*
+ * Clear the FIFO buffers and disable them.
+ * (they will be reeanbled in set_termios())
+ */
+ if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) {
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+ serial_outp(up, UART_FCR, 0);
+ }
+
+ /*
+ * Clear the interrupt registers.
+ */
+ (void) serial_inp(up, UART_LSR);
+ (void) serial_inp(up, UART_RX);
+ (void) serial_inp(up, UART_IIR);
+ (void) serial_inp(up, UART_MSR);
+
+ /*
+ * At this point, there's no way the LSR could still be 0xff;
+ * if it is, then bail out, because there's likely no UART
+ * here.
+ */
+ if (!(up->port.flags & UPF_BUGGY_UART) &&
+ (serial_inp(up, UART_LSR) == 0xff)) {
+ printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
+ return -ENODEV;
+ }
+
+ retval = serial_link_irq_chain(up);
+ if (retval)
+ return retval;
+
+ /*
+ * Now, initialize the UART
+ */
+ serial_outp(up, UART_LCR, UART_LCR_WLEN8);
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (up->port.flags & UPF_FOURPORT) {
+ if (!is_real_interrupt(up->port.irq))
+ up->port.mctrl |= TIOCM_OUT1;
+ } else
+ /*
+ * Most PC uarts need OUT2 raised to enable interrupts.
+ */
+ if (is_real_interrupt(up->port.irq))
+ up->port.mctrl |= TIOCM_OUT2;
+
+ serial8250_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ /*
+ * Finally, enable interrupts. Note: Modem status interrupts
+ * are set via set_termios(), which will be occurring imminently
+ * anyway, so we don't enable them here.
+ */
+ up->ier = UART_IER_RLSI | UART_IER_RDI;
+ serial_outp(up, UART_IER, up->ier);
+
+ if (up->port.flags & UPF_FOURPORT) {
+ unsigned int icp;
+ /*
+ * Enable interrupts on the AST Fourport board
+ */
+ icp = (up->port.iobase & 0xfe0) | 0x01f;
+ outb_p(0x80, icp);
+ (void) inb_p(icp);
+ }
+
+ /*
+ * And clear the interrupt registers again for luck.
+ */
+ (void) serial_inp(up, UART_LSR);
+ (void) serial_inp(up, UART_RX);
+ (void) serial_inp(up, UART_IIR);
+ (void) serial_inp(up, UART_MSR);
+
+ return 0;
+}
+
+static void serial8250_shutdown(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long flags;
+
+ /*
+ * Disable interrupts from this port
+ */
+ up->ier = 0;
+ serial_outp(up, UART_IER, 0);
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (up->port.flags & UPF_FOURPORT) {
+ /* reset interrupts on the AST Fourport board */
+ inb((up->port.iobase & 0xfe0) | 0x1f);
+ up->port.mctrl |= TIOCM_OUT1;
+ } else
+ up->port.mctrl &= ~TIOCM_OUT2;
+
+ serial8250_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ /*
+ * Disable break condition and FIFOs
+ */
+ serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR |
+ UART_FCR_CLEAR_XMIT);
+ serial_outp(up, UART_FCR, 0);
+
+ /*
+ * Read data port to reset things, and then unlink from
+ * the IRQ chain.
+ */
+ (void) serial_in(up, UART_RX);
+
+ if (!is_real_interrupt(up->port.irq))
+ del_timer_sync(&up->timer);
+ else
+ serial_unlink_irq_chain(up);
+}
+
+static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud)
+{
+ unsigned int quot;
+
+ /*
+ * Handle magic divisors for baud rates above baud_base on
+ * SMSC SuperIO chips.
+ */
+ if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
+ baud == (port->uartclk/4))
+ quot = 0x8001;
+ else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
+ baud == (port->uartclk/8))
+ quot = 0x8002;
+ else
+ quot = uart_get_divisor(port, baud);
+
+ return quot;
+}
+
+static void
+serial8250_set_termios(struct uart_port *port, struct termios *termios,
+ struct termios *old)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned char cval, fcr = 0;
+ unsigned long flags;
+ unsigned int baud, quot;
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ cval = 0x00;
+ break;
+ case CS6:
+ cval = 0x01;
+ break;
+ case CS7:
+ cval = 0x02;
+ break;
+ default:
+ case CS8:
+ cval = 0x03;
+ break;
+ }
+
+ if (termios->c_cflag & CSTOPB)
+ cval |= 0x04;
+ if (termios->c_cflag & PARENB)
+ cval |= UART_LCR_PARITY;
+ if (!(termios->c_cflag & PARODD))
+ cval |= UART_LCR_EPAR;
+#ifdef CMSPAR
+ if (termios->c_cflag & CMSPAR)
+ cval |= UART_LCR_SPAR;
+#endif
+
+ /*
+ * Ask the core to calculate the divisor for us.
+ */
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+ quot = serial8250_get_divisor(port, baud);
+ quot = 0x35; /* FIXME */
+
+ /*
+ * Work around a bug in the Oxford Semiconductor 952 rev B
+ * chip which causes it to seriously miscalculate baud rates
+ * when DLL is 0.
+ */
+ if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 &&
+ up->rev == 0x5201)
+ quot ++;
+
+ if (uart_config[up->port.type].flags & UART_USE_FIFO) {
+ if (baud < 2400)
+ fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_1;
+ else
+ fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_8;
+ }
+
+ /*
+ * Ok, we're now changing the port state. Do it with
+ * interrupts disabled.
+ */
+ spin_lock_irqsave(&up->port.lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+ if (termios->c_iflag & INPCK)
+ up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ up->port.read_status_mask |= UART_LSR_BI;
+
+ /*
+ * Characteres to ignore
+ */
+ up->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+ if (termios->c_iflag & IGNBRK) {
+ up->port.ignore_status_mask |= UART_LSR_BI;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= UART_LSR_OE;
+ }
+
+ /*
+ * ignore all characters if CREAD is not set
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ up->port.ignore_status_mask |= UART_LSR_DR;
+
+ /*
+ * CTS flow control flag and modem status interrupts
+ */
+ up->ier &= ~UART_IER_MSI;
+ if (UART_ENABLE_MS(&up->port, termios->c_cflag))
+ up->ier |= UART_IER_MSI;
+
+ serial_out(up, UART_IER, up->ier);
+ serial_outp(up, 0x28, quot & 0xffff);
+ up->lcr = cval; /* Save LCR */
+ if (up->port.type != PORT_16750) {
+ if (fcr & UART_FCR_ENABLE_FIFO) {
+ /* emulated UARTs (Lucent Venus 167x) need two steps */
+ serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ }
+ serial_outp(up, UART_FCR, fcr); /* set fcr */
+ }
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static void
+serial8250_pm(struct uart_port *port, unsigned int state,
+ unsigned int oldstate)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ if (state) {
+ /* sleep */
+ if (up->pm)
+ up->pm(port, state, oldstate);
+ } else {
+ /* wake */
+ if (up->pm)
+ up->pm(port, state, oldstate);
+ }
+}
+
+/*
+ * Resource handling. This is complicated by the fact that resources
+ * depend on the port type. Maybe we should be claiming the standard
+ * 8250 ports, and then trying to get other resources as necessary?
+ */
+static int
+serial8250_request_std_resource(struct uart_8250_port *up, struct resource **res)
+{
+ unsigned int size = 8 << up->port.regshift;
+ int ret = 0;
+
+ switch (up->port.iotype) {
+ case SERIAL_IO_MEM:
+ if (up->port.mapbase) {
+ *res = request_mem_region(up->port.mapbase, size, "serial");
+ if (!*res)
+ ret = -EBUSY;
+ }
+ break;
+
+ case SERIAL_IO_HUB6:
+ case SERIAL_IO_PORT:
+ *res = request_region(up->port.iobase, size, "serial");
+ if (!*res)
+ ret = -EBUSY;
+ break;
+ }
+ return ret;
+}
+
+
+static void serial8250_release_port(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned long start, offset = 0, size = 0;
+
+ size <<= up->port.regshift;
+
+ switch (up->port.iotype) {
+ case SERIAL_IO_MEM:
+ if (up->port.mapbase) {
+ /*
+ * Unmap the area.
+ */
+ iounmap(up->port.membase);
+ up->port.membase = NULL;
+
+ start = up->port.mapbase;
+
+ if (size)
+ release_mem_region(start + offset, size);
+ release_mem_region(start, 8 << up->port.regshift);
+ }
+ break;
+
+ case SERIAL_IO_HUB6:
+ case SERIAL_IO_PORT:
+ start = up->port.iobase;
+
+ if (size)
+ release_region(start + offset, size);
+ release_region(start + offset, 8 << up->port.regshift);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static int serial8250_request_port(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ struct resource *res = NULL, *res_rsa = NULL;
+ int ret = 0;
+
+ ret = serial8250_request_std_resource(up, &res);
+
+ /*
+ * If we have a mapbase, then request that as well.
+ */
+ if (ret == 0 && up->port.flags & UPF_IOREMAP) {
+ int size = res->end - res->start + 1;
+
+ up->port.membase = ioremap(up->port.mapbase, size);
+ if (!up->port.membase)
+ ret = -ENOMEM;
+ }
+
+ if (ret < 0) {
+ if (res_rsa)
+ release_resource(res_rsa);
+ if (res)
+ release_resource(res);
+ }
+ return ret;
+}
+
+static void serial8250_config_port(struct uart_port *port, int flags)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ struct resource *res_std = NULL, *res_rsa = NULL;
+ int probeflags = PROBE_ANY;
+
+ probeflags &= ~PROBE_RSA;
+
+ if (flags & UART_CONFIG_TYPE)
+ autoconfig(up, probeflags);
+
+ /*
+ * If the port wasn't an RSA port, release the resource.
+ */
+ if (up->port.type != PORT_RSA && res_rsa)
+ release_resource(res_rsa);
+
+ if (up->port.type == PORT_UNKNOWN && res_std)
+ release_resource(res_std);
+}
+
+static int
+serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ if (ser->irq >= NR_IRQS || ser->irq < 0 ||
+ ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
+ ser->type > PORT_MAX_8250 || ser->type == PORT_CIRRUS ||
+ ser->type == PORT_STARTECH)
+ return -EINVAL;
+ return 0;
+}
+
+static const char *
+serial8250_type(struct uart_port *port)
+{
+ int type = port->type;
+
+ if (type >= ARRAY_SIZE(uart_config))
+ type = 0;
+ return uart_config[type].name;
+}
+
+static struct uart_ops serial8250_pops = {
+ .tx_empty = serial8250_tx_empty,
+ .set_mctrl = serial8250_set_mctrl,
+ .get_mctrl = serial8250_get_mctrl,
+ .stop_tx = serial8250_stop_tx,
+ .start_tx = serial8250_start_tx,
+ .stop_rx = serial8250_stop_rx,
+ .enable_ms = serial8250_enable_ms,
+ .break_ctl = serial8250_break_ctl,
+ .startup = serial8250_startup,
+ .shutdown = serial8250_shutdown,
+ .set_termios = serial8250_set_termios,
+ .pm = serial8250_pm,
+ .type = serial8250_type,
+ .release_port = serial8250_release_port,
+ .request_port = serial8250_request_port,
+ .config_port = serial8250_config_port,
+ .verify_port = serial8250_verify_port,
+};
+
+static struct uart_8250_port serial8250_ports[UART_NR];
+
+static void __init serial8250_isa_init_ports(void)
+{
+ struct uart_8250_port *up;
+ static int first = 1;
+ int i;
+
+ if (!first)
+ return;
+ first = 0;
+
+ for (i = 0, up = serial8250_ports; i < ARRAY_SIZE(old_serial_port);
+ i++, up++) {
+ up->port.iobase = old_serial_port[i].port;
+ up->port.irq = old_serial_port[i].irq;
+ up->port.uartclk = get_au1x00_uart_baud_base();
+ up->port.flags = old_serial_port[i].flags;
+ up->port.hub6 = old_serial_port[i].hub6;
+ up->port.membase = old_serial_port[i].iomem_base;
+ up->port.iotype = old_serial_port[i].io_type;
+ up->port.regshift = old_serial_port[i].iomem_reg_shift;
+ up->port.ops = &serial8250_pops;
+ }
+}
+
+static void __init serial8250_register_ports(struct uart_driver *drv)
+{
+ int i;
+
+ serial8250_isa_init_ports();
+
+ for (i = 0; i < UART_NR; i++) {
+ struct uart_8250_port *up = &serial8250_ports[i];
+
+ up->port.line = i;
+ up->port.ops = &serial8250_pops;
+ init_timer(&up->timer);
+ up->timer.function = serial8250_timeout;
+
+ /*
+ * ALPHA_KLUDGE_MCR needs to be killed.
+ */
+ up->mcr_mask = ~ALPHA_KLUDGE_MCR;
+ up->mcr_force = ALPHA_KLUDGE_MCR;
+
+ uart_add_one_port(drv, &up->port);
+ }
+}
+
+#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
+
+#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
+
+/*
+ * Wait for transmitter & holding register to empty
+ */
+static inline void wait_for_xmitr(struct uart_8250_port *up)
+{
+ unsigned int status, tmout = 10000;
+
+ /* Wait up to 10ms for the character(s) to be sent. */
+ do {
+ status = serial_in(up, UART_LSR);
+
+ if (status & UART_LSR_BI)
+ up->lsr_break_flag = UART_LSR_BI;
+
+ if (--tmout == 0)
+ break;
+ udelay(1);
+ } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
+
+ /* Wait up to 1s for flow control if necessary */
+ if (up->port.flags & UPF_CONS_FLOW) {
+ tmout = 1000000;
+ while (--tmout &&
+ ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
+ udelay(1);
+ }
+}
+
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ *
+ * The console_lock must be held when we get here.
+ */
+static void
+serial8250_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct uart_8250_port *up = &serial8250_ports[co->index];
+ unsigned int ier;
+ int i;
+
+ /*
+ * First save the UER then disable the interrupts
+ */
+ ier = serial_in(up, UART_IER);
+ serial_out(up, UART_IER, 0);
+
+ /*
+ * Now, do each character
+ */
+ for (i = 0; i < count; i++, s++) {
+ wait_for_xmitr(up);
+
+ /*
+ * Send the character out.
+ * If a LF, also do CR...
+ */
+ serial_out(up, UART_TX, *s);
+ if (*s == 10) {
+ wait_for_xmitr(up);
+ serial_out(up, UART_TX, 13);
+ }
+ }
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the IER
+ */
+ wait_for_xmitr(up);
+ serial_out(up, UART_IER, ier);
+}
+
+static int __init serial8250_console_setup(struct console *co, char *options)
+{
+ struct uart_port *port;
+ int baud = 9600;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ /*
+ * Check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ if (co->index >= UART_NR)
+ co->index = 0;
+ port = &serial8250_ports[co->index].port;
+
+ /*
+ * Temporary fix.
+ */
+ spin_lock_init(&port->lock);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+extern struct uart_driver serial8250_reg;
+static struct console serial8250_console = {
+ .name = "ttyS",
+ .write = serial8250_console_write,
+ .device = uart_console_device,
+ .setup = serial8250_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &serial8250_reg,
+};
+
+static int __init serial8250_console_init(void)
+{
+ serial8250_isa_init_ports();
+ register_console(&serial8250_console);
+ return 0;
+}
+console_initcall(serial8250_console_init);
+
+#define SERIAL8250_CONSOLE &serial8250_console
+#else
+#define SERIAL8250_CONSOLE NULL
+#endif
+
+static struct uart_driver serial8250_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "serial",
+ .devfs_name = "tts/",
+ .dev_name = "ttyS",
+ .major = TTY_MAJOR,
+ .minor = 64,
+ .nr = UART_NR,
+ .cons = SERIAL8250_CONSOLE,
+};
+
+int __init early_serial_setup(struct uart_port *port)
+{
+ serial8250_isa_init_ports();
+ serial8250_ports[port->line].port = *port;
+ serial8250_ports[port->line].port.ops = &serial8250_pops;
+ return 0;
+}
+
+/**
+ * serial8250_suspend_port - suspend one serial port
+ * @line: serial line number
+ * @level: the level of port suspension, as per uart_suspend_port
+ *
+ * Suspend one serial port.
+ */
+void serial8250_suspend_port(int line)
+{
+ uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port);
+}
+
+/**
+ * serial8250_resume_port - resume one serial port
+ * @line: serial line number
+ * @level: the level of port resumption, as per uart_resume_port
+ *
+ * Resume one serial port.
+ */
+void serial8250_resume_port(int line)
+{
+ uart_resume_port(&serial8250_reg, &serial8250_ports[line].port);
+}
+
+static int __init serial8250_init(void)
+{
+ int ret, i;
+
+ printk(KERN_INFO "Serial: Au1x00 driver\n");
+
+ for (i = 0; i < NR_IRQS; i++)
+ spin_lock_init(&irq_lists[i].lock);
+
+ ret = uart_register_driver(&serial8250_reg);
+ if (ret >= 0)
+ serial8250_register_ports(&serial8250_reg);
+
+ return ret;
+}
+
+static void __exit serial8250_exit(void)
+{
+ int i;
+
+ for (i = 0; i < UART_NR; i++)
+ uart_remove_one_port(&serial8250_reg, &serial8250_ports[i].port);
+
+ uart_unregister_driver(&serial8250_reg);
+}
+
+module_init(serial8250_init);
+module_exit(serial8250_exit);
+
+EXPORT_SYMBOL(serial8250_suspend_port);
+EXPORT_SYMBOL(serial8250_resume_port);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Au1x00 serial driver\n");