diff options
Diffstat (limited to 'arch/mn10300/kernel/mn10300-serial.c')
| -rw-r--r-- | arch/mn10300/kernel/mn10300-serial.c | 1480 |
1 files changed, 1480 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/mn10300-serial.c b/arch/mn10300/kernel/mn10300-serial.c new file mode 100644 index 0000000..b9c268c --- /dev/null +++ b/arch/mn10300/kernel/mn10300-serial.c @@ -0,0 +1,1480 @@ +/* MN10300 On-chip serial port UART driver + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +static const char serial_name[] = "MN10300 Serial driver"; +static const char serial_version[] = "mn10300_serial-1.0"; +static const char serial_revdate[] = "2007-11-06"; + +#if defined(CONFIG_MN10300_TTYSM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + +#include <linux/version.h> +#include <linux/module.h> +#include <linux/serial.h> +#include <linux/circ_buf.h> +#include <linux/errno.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/timer.h> +#include <linux/interrupt.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/major.h> +#include <linux/string.h> +#include <linux/ioport.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/console.h> +#include <linux/sysrq.h> + +#include <asm/system.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/bitops.h> +#include <asm/serial-regs.h> +#include <asm/unit/timex.h> +#include "mn10300-serial.h" + +static inline __attribute__((format(printf, 1, 2))) +void no_printk(const char *fmt, ...) +{ +} + +#define kenter(FMT, ...) \ + printk(KERN_DEBUG "-->%s(" FMT ")\n", __func__, ##__VA_ARGS__) +#define _enter(FMT, ...) \ + no_printk(KERN_DEBUG "-->%s(" FMT ")\n", __func__, ##__VA_ARGS__) +#define kdebug(FMT, ...) \ + printk(KERN_DEBUG "--- " FMT "\n", ##__VA_ARGS__) +#define _debug(FMT, ...) \ + no_printk(KERN_DEBUG "--- " FMT "\n", ##__VA_ARGS__) +#define kproto(FMT, ...) \ + printk(KERN_DEBUG "### MNSERIAL " FMT " ###\n", ##__VA_ARGS__) +#define _proto(FMT, ...) \ + no_printk(KERN_DEBUG "### MNSERIAL " FMT " ###\n", ##__VA_ARGS__) + +#define NR_UARTS 3 + +#ifdef CONFIG_MN10300_TTYSM_CONSOLE +static void mn10300_serial_console_write(struct console *co, + const char *s, unsigned count); +static int __init mn10300_serial_console_setup(struct console *co, + char *options); + +static struct uart_driver mn10300_serial_driver; +static struct console mn10300_serial_console = { + .name = "ttySM", + .write = mn10300_serial_console_write, + .device = uart_console_device, + .setup = mn10300_serial_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &mn10300_serial_driver, +}; +#endif + +static struct uart_driver mn10300_serial_driver = { + .owner = NULL, + .driver_name = "mn10300-serial", + .dev_name = "ttySM", + .major = TTY_MAJOR, + .minor = 128, + .nr = NR_UARTS, +#ifdef CONFIG_MN10300_TTYSM_CONSOLE + .cons = &mn10300_serial_console, +#endif +}; + +static unsigned int mn10300_serial_tx_empty(struct uart_port *); +static void mn10300_serial_set_mctrl(struct uart_port *, unsigned int mctrl); +static unsigned int mn10300_serial_get_mctrl(struct uart_port *); +static void mn10300_serial_stop_tx(struct uart_port *); +static void mn10300_serial_start_tx(struct uart_port *); +static void mn10300_serial_send_xchar(struct uart_port *, char ch); +static void mn10300_serial_stop_rx(struct uart_port *); +static void mn10300_serial_enable_ms(struct uart_port *); +static void mn10300_serial_break_ctl(struct uart_port *, int ctl); +static int mn10300_serial_startup(struct uart_port *); +static void mn10300_serial_shutdown(struct uart_port *); +static void mn10300_serial_set_termios(struct uart_port *, + struct ktermios *new, + struct ktermios *old); +static const char *mn10300_serial_type(struct uart_port *); +static void mn10300_serial_release_port(struct uart_port *); +static int mn10300_serial_request_port(struct uart_port *); +static void mn10300_serial_config_port(struct uart_port *, int); +static int mn10300_serial_verify_port(struct uart_port *, + struct serial_struct *); + +static const struct uart_ops mn10300_serial_ops = { + .tx_empty = mn10300_serial_tx_empty, + .set_mctrl = mn10300_serial_set_mctrl, + .get_mctrl = mn10300_serial_get_mctrl, + .stop_tx = mn10300_serial_stop_tx, + .start_tx = mn10300_serial_start_tx, + .send_xchar = mn10300_serial_send_xchar, + .stop_rx = mn10300_serial_stop_rx, + .enable_ms = mn10300_serial_enable_ms, + .break_ctl = mn10300_serial_break_ctl, + .startup = mn10300_serial_startup, + .shutdown = mn10300_serial_shutdown, + .set_termios = mn10300_serial_set_termios, + .type = mn10300_serial_type, + .release_port = mn10300_serial_release_port, + .request_port = mn10300_serial_request_port, + .config_port = mn10300_serial_config_port, + .verify_port = mn10300_serial_verify_port, +}; + +static irqreturn_t mn10300_serial_interrupt(int irq, void *dev_id); + +/* + * the first on-chip serial port: ttySM0 (aka SIF0) + */ +#ifdef CONFIG_MN10300_TTYSM0 +struct mn10300_serial_port mn10300_serial_port_sif0 = { + .uart.ops = &mn10300_serial_ops, + .uart.membase = (void __iomem *) &SC0CTR, + .uart.mapbase = (unsigned long) &SC0CTR, + .uart.iotype = UPIO_MEM, + .uart.irq = 0, + .uart.uartclk = 0, /* MN10300_IOCLK, */ + .uart.fifosize = 1, + .uart.flags = UPF_BOOT_AUTOCONF, + .uart.line = 0, + .uart.type = PORT_MN10300, + .uart.lock = + __SPIN_LOCK_UNLOCKED(mn10300_serial_port_sif0.uart.lock), + .name = "ttySM0", + ._iobase = &SC0CTR, + ._control = &SC0CTR, + ._status = (volatile u8 *) &SC0STR, + ._intr = &SC0ICR, + ._rxb = &SC0RXB, + ._txb = &SC0TXB, + .rx_name = "ttySM0/Rx", + .tx_name = "ttySM0/Tx", +#ifdef CONFIG_MN10300_TTYSM0_TIMER8 + .tm_name = "ttySM0/Timer8", + ._tmxmd = &TM8MD, + ._tmxbr = &TM8BR, + ._tmicr = &TM8ICR, + .tm_irq = TM8IRQ, + .div_timer = MNSCx_DIV_TIMER_16BIT, +#else /* CONFIG_MN10300_TTYSM0_TIMER2 */ + .tm_name = "ttySM0/Timer2", + ._tmxmd = &TM2MD, + ._tmxbr = (volatile u16 *) &TM2BR, + ._tmicr = &TM2ICR, + .tm_irq = TM2IRQ, + .div_timer = MNSCx_DIV_TIMER_8BIT, +#endif + .rx_irq = SC0RXIRQ, + .tx_irq = SC0TXIRQ, + .rx_icr = &GxICR(SC0RXIRQ), + .tx_icr = &GxICR(SC0TXIRQ), + .clock_src = MNSCx_CLOCK_SRC_IOCLK, + .options = 0, +#ifdef CONFIG_GDBSTUB_ON_TTYSM0 + .gdbstub = 1, +#endif +}; +#endif /* CONFIG_MN10300_TTYSM0 */ + +/* + * the second on-chip serial port: ttySM1 (aka SIF1) + */ +#ifdef CONFIG_MN10300_TTYSM1 +struct mn10300_serial_port mn10300_serial_port_sif1 = { + .uart.ops = &mn10300_serial_ops, + .uart.membase = (void __iomem *) &SC1CTR, + .uart.mapbase = (unsigned long) &SC1CTR, + .uart.iotype = UPIO_MEM, + .uart.irq = 0, + .uart.uartclk = 0, /* MN10300_IOCLK, */ + .uart.fifosize = 1, + .uart.flags = UPF_BOOT_AUTOCONF, + .uart.line = 1, + .uart.type = PORT_MN10300, + .uart.lock = + __SPIN_LOCK_UNLOCKED(mn10300_serial_port_sif1.uart.lock), + .name = "ttySM1", + ._iobase = &SC1CTR, + ._control = &SC1CTR, + ._status = (volatile u8 *) &SC1STR, + ._intr = &SC1ICR, + ._rxb = &SC1RXB, + ._txb = &SC1TXB, + .rx_name = "ttySM1/Rx", + .tx_name = "ttySM1/Tx", +#ifdef CONFIG_MN10300_TTYSM1_TIMER9 + .tm_name = "ttySM1/Timer9", + ._tmxmd = &TM9MD, + ._tmxbr = &TM9BR, + ._tmicr = &TM9ICR, + .tm_irq = TM9IRQ, + .div_timer = MNSCx_DIV_TIMER_16BIT, +#else /* CONFIG_MN10300_TTYSM1_TIMER3 */ + .tm_name = "ttySM1/Timer3", + ._tmxmd = &TM3MD, + ._tmxbr = (volatile u16 *) &TM3BR, + ._tmicr = &TM3ICR, + .tm_irq = TM3IRQ, + .div_timer = MNSCx_DIV_TIMER_8BIT, +#endif + .rx_irq = SC1RXIRQ, + .tx_irq = SC1TXIRQ, + .rx_icr = &GxICR(SC1RXIRQ), + .tx_icr = &GxICR(SC1TXIRQ), + .clock_src = MNSCx_CLOCK_SRC_IOCLK, + .options = 0, +#ifdef CONFIG_GDBSTUB_ON_TTYSM1 + .gdbstub = 1, +#endif +}; +#endif /* CONFIG_MN10300_TTYSM1 */ + +/* + * the third on-chip serial port: ttySM2 (aka SIF2) + */ +#ifdef CONFIG_MN10300_TTYSM2 +struct mn10300_serial_port mn10300_serial_port_sif2 = { + .uart.ops = &mn10300_serial_ops, + .uart.membase = (void __iomem *) &SC2CTR, + .uart.mapbase = (unsigned long) &SC2CTR, + .uart.iotype = UPIO_MEM, + .uart.irq = 0, + .uart.uartclk = 0, /* MN10300_IOCLK, */ + .uart.fifosize = 1, + .uart.flags = UPF_BOOT_AUTOCONF, + .uart.line = 2, +#ifdef CONFIG_MN10300_TTYSM2_CTS + .uart.type = PORT_MN10300_CTS, +#else + .uart.type = PORT_MN10300, +#endif + .uart.lock = + __SPIN_LOCK_UNLOCKED(mn10300_serial_port_sif2.uart.lock), + .name = "ttySM2", + .rx_name = "ttySM2/Rx", + .tx_name = "ttySM2/Tx", + .tm_name = "ttySM2/Timer10", + ._iobase = &SC2CTR, + ._control = &SC2CTR, + ._status = &SC2STR, + ._intr = &SC2ICR, + ._rxb = &SC2RXB, + ._txb = &SC2TXB, + ._tmxmd = &TM10MD, + ._tmxbr = &TM10BR, + ._tmicr = &TM10ICR, + .tm_irq = TM10IRQ, + .div_timer = MNSCx_DIV_TIMER_16BIT, + .rx_irq = SC2RXIRQ, + .tx_irq = SC2TXIRQ, + .rx_icr = &GxICR(SC2RXIRQ), + .tx_icr = &GxICR(SC2TXIRQ), + .clock_src = MNSCx_CLOCK_SRC_IOCLK, +#ifdef CONFIG_MN10300_TTYSM2_CTS + .options = MNSCx_OPT_CTS, +#else + .options = 0, +#endif +#ifdef CONFIG_GDBSTUB_ON_TTYSM2 + .gdbstub = 1, +#endif +}; +#endif /* CONFIG_MN10300_TTYSM2 */ + + +/* + * list of available serial ports + */ +struct mn10300_serial_port *mn10300_serial_ports[NR_UARTS + 1] = { +#ifdef CONFIG_MN10300_TTYSM0 + [0] = &mn10300_serial_port_sif0, +#endif +#ifdef CONFIG_MN10300_TTYSM1 + [1] = &mn10300_serial_port_sif1, +#endif +#ifdef CONFIG_MN10300_TTYSM2 + [2] = &mn10300_serial_port_sif2, +#endif + [NR_UARTS] = NULL, +}; + + +/* + * we abuse the serial ports' baud timers' interrupt lines to get the ability + * to deliver interrupts to userspace as we use the ports' interrupt lines to + * do virtual DMA on account of the ports having no hardware FIFOs + * + * we can generate an interrupt manually in the assembly stubs by writing to + * the enable and detect bits in the interrupt control register, so all we need + * to do here is disable the interrupt line + * + * note that we can't just leave the line enabled as the baud rate timer *also* + * generates interrupts + */ +static void mn10300_serial_mask_ack(unsigned int irq) +{ + u16 tmp; + GxICR(irq) = GxICR_LEVEL_6; + tmp = GxICR(irq); /* flush write buffer */ +} + +static void mn10300_serial_nop(unsigned int irq) +{ +} + +static struct irq_chip mn10300_serial_pic = { + .name = "mnserial", + .ack = mn10300_serial_mask_ack, + .mask = mn10300_serial_mask_ack, + .mask_ack = mn10300_serial_mask_ack, + .unmask = mn10300_serial_nop, + .end = mn10300_serial_nop, +}; + + +/* + * serial virtual DMA interrupt jump table + */ +struct mn10300_serial_int mn10300_serial_int_tbl[NR_IRQS]; + +static void mn10300_serial_dis_tx_intr(struct mn10300_serial_port *port) +{ + u16 x; + *port->tx_icr = GxICR_LEVEL_1 | GxICR_DETECT; + x = *port->tx_icr; +} + +static void mn10300_serial_en_tx_intr(struct mn10300_serial_port *port) +{ + u16 x; + *port->tx_icr = GxICR_LEVEL_1 | GxICR_ENABLE; + x = *port->tx_icr; +} + +static void mn10300_serial_dis_rx_intr(struct mn10300_serial_port *port) +{ + u16 x; + *port->rx_icr = GxICR_LEVEL_1 | GxICR_DETECT; + x = *port->rx_icr; +} + +/* + * multi-bit equivalent of test_and_clear_bit() + */ +static int mask_test_and_clear(volatile u8 *ptr, u8 mask) +{ + u32 epsw; + asm volatile(" bclr %1,(%2) \n" + " mov epsw,%0 \n" + : "=d"(epsw) : "d"(mask), "a"(ptr)); + return !(epsw & EPSW_FLAG_Z); +} + +/* + * receive chars from the ring buffer for this serial port + * - must do break detection here (not done in the UART) + */ +static void mn10300_serial_receive_interrupt(struct mn10300_serial_port *port) +{ + struct uart_icount *icount = &port->uart.icount; + struct tty_struct *tty = port->uart.info->tty; + unsigned ix; + int count; + u8 st, ch, push, status, overrun; + + _enter("%s", port->name); + + push = 0; + + count = CIRC_CNT(port->rx_inp, port->rx_outp, MNSC_BUFFER_SIZE); + count = tty_buffer_request_room(tty, count); + if (count == 0) { + if (!tty->low_latency) + tty_flip_buffer_push(tty); + return; + } + +try_again: + /* pull chars out of the hat */ + ix = port->rx_outp; + if (ix == port->rx_inp) { + if (push && !tty->low_latency) + tty_flip_buffer_push(tty); + return; + } + + ch = port->rx_buffer[ix++]; + st = port->rx_buffer[ix++]; + smp_rmb(); + port->rx_outp = ix & (MNSC_BUFFER_SIZE - 1); + port->uart.icount.rx++; + + st &= SC01STR_FEF | SC01STR_PEF | SC01STR_OEF; + status = 0; + overrun = 0; + + /* the UART doesn't detect BREAK, so we have to do that ourselves + * - it starts as a framing error on a NUL character + * - then we count another two NUL characters before issuing TTY_BREAK + * - then we end on a normal char or one that has all the bottom bits + * zero and the top bits set + */ + switch (port->rx_brk) { + case 0: + /* not breaking at the moment */ + break; + + case 1: + if (st & SC01STR_FEF && ch == 0) { + port->rx_brk = 2; + goto try_again; + } + goto not_break; + + case 2: + if (st & SC01STR_FEF && ch == 0) { + port->rx_brk = 3; + _proto("Rx Break Detected"); + icount->brk++; + if (uart_handle_break(&port->uart)) + goto ignore_char; + status |= 1 << TTY_BREAK; + goto insert; + } + goto not_break; + + default: + if (st & (SC01STR_FEF | SC01STR_PEF | SC01STR_OEF)) + goto try_again; /* still breaking */ + + port->rx_brk = 0; /* end of the break */ + + switch (ch) { + case 0xFF: + case 0xFE: + case 0xFC: + case 0xF8: + case 0xF0: + case 0xE0: + case 0xC0: + case 0x80: + case 0x00: + /* discard char at probable break end */ + goto try_again; + } + break; + } + +process_errors: + /* handle framing error */ + if (st & SC01STR_FEF) { + if (ch == 0) { + /* framing error with NUL char is probably a BREAK */ + port->rx_brk = 1; + goto try_again; + } + + _proto("Rx Framing Error"); + icount->frame++; + status |= 1 << TTY_FRAME; + } + + /* handle parity error */ + if (st & SC01STR_PEF) { + _proto("Rx Parity Error"); + icount->parity++; + status = TTY_PARITY; + } + + /* handle normal char */ + if (status == 0) { + if (uart_handle_sysrq_char(&port->uart, ch)) + goto ignore_char; + status = (1 << TTY_NORMAL); + } + + /* handle overrun error */ + if (st & SC01STR_OEF) { + if (port->rx_brk) + goto try_again; + + _proto("Rx Overrun Error"); + icount->overrun++; + overrun = 1; + } + +insert: + status &= port->uart.read_status_mask; + + if (!overrun && !(status & port->uart.ignore_status_mask)) { + int flag; + + if (status & (1 << TTY_BREAK)) + flag = TTY_BREAK; + else if (status & (1 << TTY_PARITY)) + flag = TTY_PARITY; + else if (status & (1 << TTY_FRAME)) + flag = TTY_FRAME; + else + flag = TTY_NORMAL; + + tty_insert_flip_char(tty, ch, flag); + } + + /* overrun is special, since it's reported immediately, and doesn't + * affect the current character + */ + if (overrun) + tty_insert_flip_char(tty, 0, TTY_OVERRUN); + + count--; + if (count <= 0) { + if (!tty->low_latency) + tty_flip_buffer_push(tty); + return; + } + +ignore_char: + push = 1; + goto try_again; + +not_break: + port->rx_brk = 0; + goto process_errors; +} + +/* + * handle an interrupt from the serial transmission "virtual DMA" driver + * - note: the interrupt routine will disable its own interrupts when the Tx + * buffer is empty + */ +static void mn10300_serial_transmit_interrupt(struct mn10300_serial_port *port) +{ + _enter("%s", port->name); + + if (uart_tx_stopped(&port->uart) || + uart_circ_empty(&port->uart.info->xmit)) + mn10300_serial_dis_tx_intr(port); + + if (uart_circ_chars_pending(&port->uart.info->xmit) < WAKEUP_CHARS) + uart_write_wakeup(&port->uart); +} + +/* + * deal with a change in the status of the CTS line + */ +static void mn10300_serial_cts_changed(struct mn10300_serial_port *port, u8 st) +{ + u16 ctr; + + port->tx_cts = st; + port->uart.icount.cts++; + + /* flip the CTS state selector flag to interrupt when it changes + * back */ + ctr = *port->_control; + ctr ^= SC2CTR_TWS; + *port->_control = ctr; + + uart_handle_cts_change(&port->uart, st & SC2STR_CTS); + wake_up_interruptible(&port->uart.info->delta_msr_wait); +} + +/* + * handle a virtual interrupt generated by the lower level "virtual DMA" + * routines (irq is the baud timer interrupt) + */ +static irqreturn_t mn10300_serial_interrupt(int irq, void *dev_id) +{ + struct mn10300_serial_port *port = dev_id; + u8 st; + + spin_lock(&port->uart.lock); + + if (port->intr_flags) { + _debug("INT %s: %x", port->name, port->intr_flags); + + if (mask_test_and_clear(&port->intr_flags, MNSCx_RX_AVAIL)) + mn10300_serial_receive_interrupt(port); + + if (mask_test_and_clear(&port->intr_flags, + MNSCx_TX_SPACE | MNSCx_TX_EMPTY)) + mn10300_serial_transmit_interrupt(port); + } + + /* the only modem control line amongst the whole lot is CTS on + * serial port 2 */ + if (port->type == PORT_MN10300_CTS) { + st = *port->_status; + if ((port->tx_cts ^ st) & SC2STR_CTS) + mn10300_serial_cts_changed(port, st); + } + + spin_unlock(&port->uart.lock); + + return IRQ_HANDLED; +} + +/* + * return indication of whether the hardware transmit buffer is empty + */ +static unsigned int mn10300_serial_tx_empty(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + return (*port->_status & (SC01STR_TXF | SC01STR_TBF)) ? + 0 : TIOCSER_TEMT; +} + +/* + * set the modem control lines (we don't have any) + */ +static void mn10300_serial_set_mctrl(struct uart_port *_port, + unsigned int mctrl) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s,%x", port->name, mctrl); +} + +/* + * get the modem control line statuses + */ +static unsigned int mn10300_serial_get_mctrl(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + if (port->type == PORT_MN10300_CTS && !(*port->_status & SC2STR_CTS)) + return TIOCM_CAR | TIOCM_DSR; + + return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR; +} + +/* + * stop transmitting characters + */ +static void mn10300_serial_stop_tx(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + /* disable the virtual DMA */ + mn10300_serial_dis_tx_intr(port); +} + +/* + * start transmitting characters + * - jump-start transmission if it has stalled + * - enable the serial Tx interrupt (used by the virtual DMA controller) + * - force an interrupt to happen if necessary + */ +static void mn10300_serial_start_tx(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + u16 x; + + _enter("%s{%lu}", + port->name, + CIRC_CNT(&port->uart.info->xmit.head, + &port->uart.info->xmit.tail, + UART_XMIT_SIZE)); + + /* kick the virtual DMA controller */ + x = *port->tx_icr; + x |= GxICR_ENABLE; + + if (*port->_status & SC01STR_TBF) + x &= ~(GxICR_REQUEST | GxICR_DETECT); + else + x |= GxICR_REQUEST | GxICR_DETECT; + + _debug("CTR=%04hx ICR=%02hx STR=%04x TMD=%02hx TBR=%04hx ICR=%04hx", + *port->_control, *port->_intr, *port->_status, + *port->_tmxmd, *port->_tmxbr, *port->tx_icr); + + *port->tx_icr = x; + x = *port->tx_icr; +} + +/* + * transmit a high-priority XON/XOFF character + */ +static void mn10300_serial_send_xchar(struct uart_port *_port, char ch) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s,%02x", port->name, ch); + + if (likely(port->gdbstub)) { + port->tx_xchar = ch; + if (ch) + mn10300_serial_en_tx_intr(port); + } +} + +/* + * stop receiving characters + * - called whilst the port is being closed + */ +static void mn10300_serial_stop_rx(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + u16 ctr; + + _enter("%s", port->name); + + ctr = *port->_control; + ctr &= ~SC01CTR_RXE; + *port->_control = ctr; + + mn10300_serial_dis_rx_intr(port); +} + +/* + * enable modem status interrupts + */ +static void mn10300_serial_enable_ms(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + u16 ctr, cts; + + _enter("%s", port->name); + + if (port->type == PORT_MN10300_CTS) { + /* want to interrupt when CTS goes low if CTS is now high and + * vice versa + */ + port->tx_cts = *port->_status; + + cts = (port->tx_cts & SC2STR_CTS) ? + SC2CTR_TWE : SC2CTR_TWE | SC2CTR_TWS; + + ctr = *port->_control; + ctr &= ~SC2CTR_TWS; + ctr |= cts; + *port->_control = ctr; + + mn10300_serial_en_tx_intr(port); + } +} + +/* + * transmit or cease transmitting a break signal + */ +static void mn10300_serial_break_ctl(struct uart_port *_port, int ctl) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s,%d", port->name, ctl); + + if (ctl) { + /* tell the virtual DMA handler to assert BREAK */ + port->tx_break = 1; + mn10300_serial_en_tx_intr(port); + } else { + port->tx_break = 0; + *port->_control &= ~SC01CTR_BKE; + mn10300_serial_en_tx_intr(port); + } +} + +/* + * grab the interrupts and enable the port for reception + */ +static int mn10300_serial_startup(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + struct mn10300_serial_int *pint; + + _enter("%s{%d}", port->name, port->gdbstub); + + if (unlikely(port->gdbstub)) + return -EBUSY; + + /* allocate an Rx buffer for the virtual DMA handler */ + port->rx_buffer = kmalloc(MNSC_BUFFER_SIZE, GFP_KERNEL); + if (!port->rx_buffer) + return -ENOMEM; + + port->rx_inp = port->rx_outp = 0; + + /* finally, enable the device */ + *port->_intr = SC01ICR_TI; + *port->_control |= SC01CTR_TXE | SC01CTR_RXE; + + pint = &mn10300_serial_int_tbl[port->rx_irq]; + pint->port = port; + pint->vdma = mn10300_serial_vdma_rx_handler; + pint = &mn10300_serial_int_tbl[port->tx_irq]; + pint->port = port; + pint->vdma = mn10300_serial_vdma_tx_handler; + + set_intr_level(port->rx_irq, GxICR_LEVEL_1); + set_intr_level(port->tx_irq, GxICR_LEVEL_1); + set_irq_chip(port->tm_irq, &mn10300_serial_pic); + + if (request_irq(port->rx_irq, mn10300_serial_interrupt, + IRQF_DISABLED, port->rx_name, port) < 0) + goto error; + + if (request_irq(port->tx_irq, mn10300_serial_interrupt, + IRQF_DISABLED, port->tx_name, port) < 0) + goto error2; + + if (request_irq(port->tm_irq, mn10300_serial_interrupt, + IRQF_DISABLED, port->tm_name, port) < 0) + goto error3; + mn10300_serial_mask_ack(port->tm_irq); + + return 0; + +error3: + free_irq(port->tx_irq, port); +error2: + free_irq(port->rx_irq, port); +error: + kfree(port->rx_buffer); + port->rx_buffer = NULL; + return -EBUSY; +} + +/* + * shutdown the port and release interrupts + */ +static void mn10300_serial_shutdown(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + /* disable the serial port and its baud rate timer */ + port->tx_break = 0; + *port->_control &= ~(SC01CTR_TXE | SC01CTR_RXE | SC01CTR_BKE); + *port->_tmxmd = 0; + + if (port->rx_buffer) { + void *buf = port->rx_buffer; + port->rx_buffer = NULL; + kfree(buf); + } + + /* disable all intrs */ + free_irq(port->tm_irq, port); + free_irq(port->rx_irq, port); + free_irq(port->tx_irq, port); + + *port->rx_icr = GxICR_LEVEL_1; + *port->tx_icr = GxICR_LEVEL_1; +} + +/* + * this routine is called to set the UART divisor registers to match the + * specified baud rate for a serial port. + */ +static void mn10300_serial_change_speed(struct mn10300_serial_port *port, + struct ktermios *new, + struct ktermios *old) +{ + unsigned long flags; + unsigned long ioclk = port->ioclk; + unsigned cflag; + int baud, bits, xdiv, tmp; + u16 tmxbr, scxctr; + u8 tmxmd, battempt; + u8 div_timer = port->div_timer; + + _enter("%s{%lu}", port->name, ioclk); + + /* byte size and parity */ + cflag = new->c_cflag; + switch (cflag & CSIZE) { + case CS7: scxctr = SC01CTR_CLN_7BIT; bits = 9; break; + case CS8: scxctr = SC01CTR_CLN_8BIT; bits = 10; break; + default: scxctr = SC01CTR_CLN_8BIT; bits = 10; break; + } + + if (cflag & CSTOPB) { + scxctr |= SC01CTR_STB_2BIT; + bits++; + } + + if (cflag & PARENB) { + bits++; + if (cflag & PARODD) + scxctr |= SC01CTR_PB_ODD; +#ifdef CMSPAR + else if (cflag & CMSPAR) + scxctr |= SC01CTR_PB_FIXED0; +#endif + else + scxctr |= SC01CTR_PB_EVEN; + } + + /* Determine divisor based on baud rate */ + battempt = 0; + + if (div_timer == MNSCx_DIV_TIMER_16BIT) + scxctr |= SC0CTR_CK_TM8UFLOW_8; /* ( == SC1CTR_CK_TM9UFLOW_8 + * == SC2CTR_CK_TM10UFLOW) */ + else if (div_timer == MNSCx_DIV_TIMER_8BIT) + scxctr |= SC0CTR_CK_TM2UFLOW_8; + +try_alternative: + baud = uart_get_baud_rate(&port->uart, new, old, 0, + port->ioclk / 8); + + _debug("ALT %d [baud %d]", battempt, baud); + + if (!baud) + baud = 9600; /* B0 transition handled in rs_set_termios */ + xdiv = 1; + if (baud == 134) { + baud = 269; /* 134 is really 134.5 */ + xdiv = 2; + } + + if (baud == 38400 && + (port->uart.flags & UPF_SPD_MASK) == UPF_SPD_CUST + ) { + _debug("CUSTOM %u", port->uart.custom_divisor); + + if (div_timer == MNSCx_DIV_TIMER_16BIT) { + if (port->uart.custom_divisor <= 65535) { + tmxmd = TM8MD_SRC_IOCLK; + tmxbr = port->uart.custom_divisor; + port->uart.uartclk = ioclk; + goto timer_okay; + } + if (port->uart.custom_divisor / 8 <= 65535) { + tmxmd = TM8MD_SRC_IOCLK_8; + tmxbr = port->uart.custom_divisor / 8; + port->uart.custom_divisor = tmxbr * 8; + port->uart.uartclk = ioclk / 8; + goto timer_okay; + } + if (port->uart.custom_divisor / 32 <= 65535) { + tmxmd = TM8MD_SRC_IOCLK_32; + tmxbr = port->uart.custom_divisor / 32; + port->uart.custom_divisor = tmxbr * 32; + port->uart.uartclk = ioclk / 32; + goto timer_okay; + } + + } else if (div_timer == MNSCx_DIV_TIMER_8BIT) { + if (port->uart.custom_divisor <= 255) { + tmxmd = TM2MD_SRC_IOCLK; + tmxbr = port->uart.custom_divisor; + port->uart.uartclk = ioclk; + goto timer_okay; + } + if (port->uart.custom_divisor / 8 <= 255) { + tmxmd = TM2MD_SRC_IOCLK_8; + tmxbr = port->uart.custom_divisor / 8; + port->uart.custom_divisor = tmxbr * 8; + port->uart.uartclk = ioclk / 8; + goto timer_okay; + } + if (port->uart.custom_divisor / 32 <= 255) { + tmxmd = TM2MD_SRC_IOCLK_32; + tmxbr = port->uart.custom_divisor / 32; + port->uart.custom_divisor = tmxbr * 32; + port->uart.uartclk = ioclk / 32; + goto timer_okay; + } + } + } + + switch (div_timer) { + case MNSCx_DIV_TIMER_16BIT: + port->uart.uartclk = ioclk; + tmxmd = TM8MD_SRC_IOCLK; + tmxbr = tmp = (ioclk / (baud * xdiv) + 4) / 8 - 1; + if (tmp > 0 && tmp <= 65535) + goto timer_okay; + + port->uart.uartclk = ioclk / 8; + tmxmd = TM8MD_SRC_IOCLK_8; + tmxbr = tmp = (ioclk / (baud * 8 * xdiv) + 4) / 8 - 1; + if (tmp > 0 && tmp <= 65535) + goto timer_okay; + + port->uart.uartclk = ioclk / 32; + tmxmd = TM8MD_SRC_IOCLK_32; + tmxbr = tmp = (ioclk / (baud * 32 * xdiv) + 4) / 8 - 1; + if (tmp > 0 && tmp <= 65535) + goto timer_okay; + break; + + case MNSCx_DIV_TIMER_8BIT: + port->uart.uartclk = ioclk; + tmxmd = TM2MD_SRC_IOCLK; + tmxbr = tmp = (ioclk / (baud * xdiv) + 4) / 8 - 1; + if (tmp > 0 && tmp <= 255) + goto timer_okay; + + port->uart.uartclk = ioclk / 8; + tmxmd = TM2MD_SRC_IOCLK_8; + tmxbr = tmp = (ioclk / (baud * 8 * xdiv) + 4) / 8 - 1; + if (tmp > 0 && tmp <= 255) + goto timer_okay; + + port->uart.uartclk = ioclk / 32; + tmxmd = TM2MD_SRC_IOCLK_32; + tmxbr = tmp = (ioclk / (baud * 32 * xdiv) + 4) / 8 - 1; + if (tmp > 0 && tmp <= 255) + goto timer_okay; + break; + + default: + BUG(); + return; + } + + /* refuse to change to a baud rate we can't support */ + _debug("CAN'T SUPPORT"); + + switch (battempt) { + case 0: + if (old) { + new->c_cflag &= ~CBAUD; + new->c_cflag |= (old->c_cflag & CBAUD); + battempt = 1; + goto try_alternative; + } + + case 1: + /* as a last resort, if the quotient is zero, default to 9600 + * bps */ + new->c_cflag &= ~CBAUD; + new->c_cflag |= B9600; + battempt = 2; + goto try_alternative; + + default: + /* hmmm... can't seem to support 9600 either + * - we could try iterating through the speeds we know about to + * find the lowest + */ + new->c_cflag &= ~CBAUD; + new->c_cflag |= B0; + + if (div_timer == MNSCx_DIV_TIMER_16BIT) + tmxmd = TM8MD_SRC_IOCLK_32; + else if (div_timer == MNSCx_DIV_TIMER_8BIT) + tmxmd = TM2MD_SRC_IOCLK_32; + tmxbr = 1; + + port->uart.uartclk = ioclk / 32; + break; + } +timer_okay: + + _debug("UARTCLK: %u / %hu", port->uart.uartclk, tmxbr); + + /* make the changes */ + spin_lock_irqsave(&port->uart.lock, flags); + + uart_update_timeout(&port->uart, new->c_cflag, baud); + + /* set the timer to produce the required baud rate */ + switch (div_timer) { + case MNSCx_DIV_TIMER_16BIT: + *port->_tmxmd = 0; + *port->_tmxbr = tmxbr; + *port->_tmxmd = TM8MD_INIT_COUNTER; + *port->_tmxmd = tmxmd | TM8MD_COUNT_ENABLE; + break; + + case MNSCx_DIV_TIMER_8BIT: + *port->_tmxmd = 0; + *(volatile u8 *) port->_tmxbr = (u8) tmxbr; + *port->_tmxmd = TM2MD_INIT_COUNTER; + *port->_tmxmd = tmxmd | TM2MD_COUNT_ENABLE; + break; + } + + /* CTS flow control flag and modem status interrupts */ + scxctr &= ~(SC2CTR_TWE | SC2CTR_TWS); + + if (port->type == PORT_MN10300_CTS && cflag & CRTSCTS) { + /* want to interrupt when CTS goes low if CTS is now + * high and vice versa + */ + port->tx_cts = *port->_status; + + if (port->tx_cts & SC2STR_CTS) + scxctr |= SC2CTR_TWE; + else + scxctr |= SC2CTR_TWE | SC2CTR_TWS; + } + + /* set up parity check flag */ + port->uart.read_status_mask = (1 << TTY_NORMAL) | (1 << TTY_OVERRUN); + if (new->c_iflag & INPCK) + port->uart.read_status_mask |= + (1 << TTY_PARITY) | (1 << TTY_FRAME); + if (new->c_iflag & (BRKINT | PARMRK)) + port->uart.read_status_mask |= (1 << TTY_BREAK); + + /* characters to ignore */ + port->uart.ignore_status_mask = 0; + if (new->c_iflag & IGNPAR) + port->uart.ignore_status_mask |= + (1 << TTY_PARITY) | (1 << TTY_FRAME); + if (new->c_iflag & IGNBRK) { + port->uart.ignore_status_mask |= (1 << TTY_BREAK); + /* + * If we're ignoring parity and break indicators, + * ignore overruns to (for real raw support). + */ + if (new->c_iflag & IGNPAR) + port->uart.ignore_status_mask |= (1 << TTY_OVERRUN); + } + + /* Ignore all characters if CREAD is not set */ + if ((new->c_cflag & CREAD) == 0) + port->uart.ignore_status_mask |= (1 << TTY_NORMAL); + + scxctr |= *port->_control & (SC01CTR_TXE | SC01CTR_RXE | SC01CTR_BKE); + *port->_control = scxctr; + + spin_unlock_irqrestore(&port->uart.lock, flags); +} + +/* + * set the terminal I/O parameters + */ +static void mn10300_serial_set_termios(struct uart_port *_port, + struct ktermios *new, + struct ktermios *old) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s,%p,%p", port->name, new, old); + + mn10300_serial_change_speed(port, new, old); + + /* handle turning off CRTSCTS */ + if (!(new->c_cflag & CRTSCTS)) { + u16 ctr = *port->_control; + ctr &= ~SC2CTR_TWE; + *port->_control = ctr; + } +} + +/* + * return description of port type + */ +static const char *mn10300_serial_type(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + if (port->uart.type == PORT_MN10300_CTS) + return "MN10300 SIF_CTS"; + + return "MN10300 SIF"; +} + +/* + * release I/O and memory regions in use by port + */ +static void mn10300_serial_release_port(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + release_mem_region((unsigned long) port->_iobase, 16); +} + +/* + * request I/O and memory regions for port + */ +static int mn10300_serial_request_port(struct uart_port *_port) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + request_mem_region((unsigned long) port->_iobase, 16, port->name); + return 0; +} + +/* + * configure the type and reserve the ports + */ +static void mn10300_serial_config_port(struct uart_port *_port, int type) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + + _enter("%s", port->name); + + port->uart.type = PORT_MN10300; + + if (port->options & MNSCx_OPT_CTS) + port->uart.type = PORT_MN10300_CTS; + + mn10300_serial_request_port(_port); +} + +/* + * verify serial parameters are suitable for this port type + */ +static int mn10300_serial_verify_port(struct uart_port *_port, + struct serial_struct *ss) +{ + struct mn10300_serial_port *port = + container_of(_port, struct mn10300_serial_port, uart); + void *mapbase = (void *) (unsigned long) port->uart.mapbase; + + _enter("%s", port->name); + + /* these things may not be changed */ + if (ss->irq != port->uart.irq || + ss->port != port->uart.iobase || + ss->io_type != port->uart.iotype || + ss->iomem_base != mapbase || + ss->iomem_reg_shift != port->uart.regshift || + ss->hub6 != port->uart.hub6 || + ss->xmit_fifo_size != port->uart.fifosize) + return -EINVAL; + + /* type may be changed on a port that supports CTS */ + if (ss->type != port->uart.type) { + if (!(port->options & MNSCx_OPT_CTS)) + return -EINVAL; + + if (ss->type != PORT_MN10300 && + ss->type != PORT_MN10300_CTS) + return -EINVAL; + } + + return 0; +} + +/* + * initialise the MN10300 on-chip UARTs + */ +static int __init mn10300_serial_init(void) +{ + struct mn10300_serial_port *port; + int ret, i; + + printk(KERN_INFO "%s version %s (%s)\n", + serial_name, serial_version, serial_revdate); + +#ifdef CONFIG_MN10300_TTYSM2 + SC2TIM = 8; /* make the baud base of timer 2 IOCLK/8 */ +#endif + + set_intr_stub(EXCEP_IRQ_LEVEL1, mn10300_serial_vdma_interrupt); + + ret = uart_register_driver(&mn10300_serial_driver); + if (!ret) { + for (i = 0 ; i < NR_PORTS ; i++) { + port = mn10300_serial_ports[i]; + if (!port || port->gdbstub) + continue; + + switch (port->clock_src) { + case MNSCx_CLOCK_SRC_IOCLK: + port->ioclk = MN10300_IOCLK; + break; + +#ifdef MN10300_IOBCLK + case MNSCx_CLOCK_SRC_IOBCLK: + port->ioclk = MN10300_IOBCLK; + break; +#endif + default: + BUG(); + } + + ret = uart_add_one_port(&mn10300_serial_driver, + &port->uart); + + if (ret < 0) { + _debug("ERROR %d", -ret); + break; + } + } + + if (ret) + uart_unregister_driver(&mn10300_serial_driver); + } + + return ret; +} + +__initcall(mn10300_serial_init); + + +#ifdef CONFIG_MN10300_TTYSM_CONSOLE + +/* + * print a string to the serial port without disturbing the real user of the + * port too much + * - the console must be locked by the caller + */ +static void mn10300_serial_console_write(struct console *co, + const char *s, unsigned count) +{ + struct mn10300_serial_port *port; + unsigned i; + u16 scxctr, txicr, tmp; + u8 tmxmd; + + port = mn10300_serial_ports[co->index]; + + /* firstly hijack the serial port from the "virtual DMA" controller */ + txicr = *port->tx_icr; + *port->tx_icr = GxICR_LEVEL_1; + tmp = *port->tx_icr; + + /* the transmitter may be disabled */ + scxctr = *port->_control; + if (!(scxctr & SC01CTR_TXE)) { + /* restart the UART clock */ + tmxmd = *port->_tmxmd; + + switch (port->div_timer) { + case MNSCx_DIV_TIMER_16BIT: + *port->_tmxmd = 0; + *port->_tmxmd = TM8MD_INIT_COUNTER; + *port->_tmxmd = tmxmd | TM8MD_COUNT_ENABLE; + break; + + case MNSCx_DIV_TIMER_8BIT: + *port->_tmxmd = 0; + *port->_tmxmd = TM2MD_INIT_COUNTER; + *port->_tmxmd = tmxmd | TM2MD_COUNT_ENABLE; + break; + } + + /* enable the transmitter */ + *port->_control = (scxctr & ~SC01CTR_BKE) | SC01CTR_TXE; + + } else if (scxctr & SC01CTR_BKE) { + /* stop transmitting BREAK */ + *port->_control = (scxctr & ~SC01CTR_BKE); + } + + /* send the chars into the serial port (with LF -> LFCR conversion) */ + for (i = 0; i < count; i++) { + char ch = *s++; + + while (*port->_status & SC01STR_TBF) + continue; + *(u8 *) port->_txb = ch; + + if (ch == 0x0a) { + while (*port->_status & SC01STR_TBF) + continue; + *(u8 *) port->_txb = 0xd; + } + } + + /* can't let the transmitter be turned off if it's actually + * transmitting */ + while (*port->_status & (SC01STR_TXF | SC01STR_TBF)) + continue; + + /* disable the transmitter if we re-enabled it */ + if (!(scxctr & SC01CTR_TXE)) + *port->_control = scxctr; + + *port->tx_icr = txicr; + tmp = *port->tx_icr; +} + +/* + * set up a serial port as a console + * - construct a cflag setting for the first rs_open() + * - initialize the serial port + * - return non-zero if we didn't find a serial port. + */ +static int __init mn10300_serial_console_setup(struct console *co, + char *options) +{ + struct mn10300_serial_port *port; + int i, parity = 'n', baud = 9600, bits = 8, flow = 0; + + for (i = 0 ; i < NR_PORTS ; i++) { + port = mn10300_serial_ports[i]; + if (port && !port->gdbstub && port->uart.line == co->index) + goto found_device; + } + + return -ENODEV; + +found_device: + switch (port->clock_src) { + case MNSCx_CLOCK_SRC_IOCLK: + port->ioclk = MN10300_IOCLK; + break; + +#ifdef MN10300_IOBCLK + case MNSCx_CLOCK_SRC_IOBCLK: + port->ioclk = MN10300_IOBCLK; + break; +#endif + default: + BUG(); + } + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(&port->uart, co, baud, parity, bits, flow); +} + +/* + * register console + */ +static int __init mn10300_serial_console_init(void) +{ + register_console(&mn10300_serial_console); + return 0; +} + +console_initcall(mn10300_serial_console_init); +#endif |
