diff options
Diffstat (limited to 'drivers/serial/au1x00_uart.c')
| -rw-r--r-- | drivers/serial/au1x00_uart.c | 1312 |
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 00000000000..b6d3d503494 --- /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"); |