diff options
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/Kconfig | 34 | ||||
| -rw-r--r-- | drivers/serial/Makefile | 1 | ||||
| -rw-r--r-- | drivers/serial/at91_serial.c | 894 |
3 files changed, 929 insertions, 0 deletions
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 1bae26a..a256a02 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -280,6 +280,40 @@ config SERIAL_AMBA_PL011_CONSOLE your boot loader (lilo or loadlin) about how to pass options to the kernel at boot time.) +config SERIAL_AT91 + bool "AT91RM9200 serial port support" + depends on ARM && ARCH_AT91RM9200 + select SERIAL_CORE + help + This enables the driver for the on-chip UARTs of the AT91RM9200 + processor. + +config SERIAL_AT91_CONSOLE + bool "Support for console on AT91RM9200 serial port" + depends on SERIAL_AT91=y + select SERIAL_CORE_CONSOLE + help + Say Y here if you wish to use a UART on the AT91RM9200 as the system + console (the system console is the device which receives all kernel + messages and warnings and which allows logins in single user mode). + +config SERIAL_AT91_TTYAT + bool "Install as device ttyAT0-4 instead of ttyS0-4" + depends on SERIAL_AT91=y + help + Say Y here if you wish to have the five internal AT91RM9200 UARTs + appear as /dev/ttyAT0-4 (major 240, minor 0-4) instead of the + normal /dev/ttyS0-4 (major 4, minor 64-68). This is necessary if + you also want other UARTs, such as external 8250/16C550 compatible + UARTs. + The ttySn nodes are legally reserved for the 8250 serial driver + but are often misused by other serial drivers. + + To use this, you should create suitable ttyATn device nodes in + /dev/, and pass "console=ttyATn" to the kernel. + + Say Y if you have an external 8250/16C550 UART. If unsure, say N. + config SERIAL_CLPS711X tristate "CLPS711X serial port support" depends on ARM && ARCH_CLPS711X diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index 137148b..24a583e 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -56,3 +56,4 @@ obj-$(CONFIG_SERIAL_JSM) += jsm/ obj-$(CONFIG_SERIAL_TXX9) += serial_txx9.o obj-$(CONFIG_SERIAL_VR41XX) += vr41xx_siu.o obj-$(CONFIG_SERIAL_SGI_IOC4) += ioc4_serial.o +obj-$(CONFIG_SERIAL_AT91) += at91_serial.o diff --git a/drivers/serial/at91_serial.c b/drivers/serial/at91_serial.c new file mode 100644 index 0000000..0e20606 --- /dev/null +++ b/drivers/serial/at91_serial.c @@ -0,0 +1,894 @@ +/* + * linux/drivers/char/at91_serial.c + * + * Driver for Atmel AT91RM9200 Serial ports + * + * Copyright (C) 2003 Rick Bronson + * + * Based on drivers/char/serial_sa1100.c, by Deep Blue Solutions Ltd. + * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ +#include <linux/config.h> +#include <linux/module.h> +#include <linux/tty.h> +#include <linux/ioport.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/serial.h> +#include <linux/console.h> +#include <linux/sysrq.h> +#include <linux/tty_flip.h> + +#include <asm/io.h> + +#include <asm/arch/at91rm9200_usart.h> +#include <asm/mach/serial_at91rm9200.h> +#include <asm/arch/board.h> +#include <asm/arch/pio.h> + + +#if defined(CONFIG_SERIAL_AT91_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + +#include <linux/serial_core.h> + +#ifdef CONFIG_SERIAL_AT91_TTYAT + +/* Use device name ttyAT, major 204 and minor 154-169. This is necessary if we + * should coexist with the 8250 driver, such as if we have an external 16C550 + * UART. */ +#define SERIAL_AT91_MAJOR 204 +#define MINOR_START 154 +#define AT91_DEVICENAME "ttyAT" + +#else + +/* Use device name ttyS, major 4, minor 64-68. This is the usual serial port + * name, but it is legally reserved for the 8250 driver. */ +#define SERIAL_AT91_MAJOR TTY_MAJOR +#define MINOR_START 64 +#define AT91_DEVICENAME "ttyS" + +#endif + +#define AT91_VA_BASE_DBGU ((unsigned long) AT91_VA_BASE_SYS + AT91_DBGU) +#define AT91_ISR_PASS_LIMIT 256 + +#define UART_PUT_CR(port,v) writel(v, (port)->membase + AT91_US_CR) +#define UART_GET_MR(port) readl((port)->membase + AT91_US_MR) +#define UART_PUT_MR(port,v) writel(v, (port)->membase + AT91_US_MR) +#define UART_PUT_IER(port,v) writel(v, (port)->membase + AT91_US_IER) +#define UART_PUT_IDR(port,v) writel(v, (port)->membase + AT91_US_IDR) +#define UART_GET_IMR(port) readl((port)->membase + AT91_US_IMR) +#define UART_GET_CSR(port) readl((port)->membase + AT91_US_CSR) +#define UART_GET_CHAR(port) readl((port)->membase + AT91_US_RHR) +#define UART_PUT_CHAR(port,v) writel(v, (port)->membase + AT91_US_THR) +#define UART_GET_BRGR(port) readl((port)->membase + AT91_US_BRGR) +#define UART_PUT_BRGR(port,v) writel(v, (port)->membase + AT91_US_BRGR) +#define UART_PUT_RTOR(port,v) writel(v, (port)->membase + AT91_US_RTOR) + +// #define UART_GET_CR(port) readl((port)->membase + AT91_US_CR) // is write-only + + /* PDC registers */ +#define UART_PUT_PTCR(port,v) writel(v, (port)->membase + AT91_PDC_PTCR) +#define UART_PUT_RPR(port,v) writel(v, (port)->membase + AT91_PDC_RPR) +#define UART_PUT_RCR(port,v) writel(v, (port)->membase + AT91_PDC_RCR) +#define UART_GET_RCR(port) readl((port)->membase + AT91_PDC_RCR) +#define UART_PUT_RNPR(port,v) writel(v, (port)->membase + AT91_PDC_RNPR) +#define UART_PUT_RNCR(port,v) writel(v, (port)->membase + AT91_PDC_RNCR) + + +static int (*at91_open)(struct uart_port *); +static void (*at91_close)(struct uart_port *); + +#ifdef SUPPORT_SYSRQ +static struct console at91_console; +#endif + +/* + * Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty. + */ +static u_int at91_tx_empty(struct uart_port *port) +{ + return (UART_GET_CSR(port) & AT91_US_TXEMPTY) ? TIOCSER_TEMT : 0; +} + +/* + * Set state of the modem control output lines + */ +static void at91_set_mctrl(struct uart_port *port, u_int mctrl) +{ + unsigned int control = 0; + + /* + * Errata #39: RTS0 is not internally connected to PA21. We need to drive + * the pin manually. + */ + if (port->mapbase == AT91_VA_BASE_US0) { + if (mctrl & TIOCM_RTS) + at91_sys_write(AT91_PIOA + PIO_CODR, AT91_PA21_RTS0); + else + at91_sys_write(AT91_PIOA + PIO_SODR, AT91_PA21_RTS0); + } + + if (mctrl & TIOCM_RTS) + control |= AT91_US_RTSEN; + else + control |= AT91_US_RTSDIS; + + if (mctrl & TIOCM_DTR) + control |= AT91_US_DTREN; + else + control |= AT91_US_DTRDIS; + + UART_PUT_CR(port,control); +} + +/* + * Get state of the modem control input lines + */ +static u_int at91_get_mctrl(struct uart_port *port) +{ + unsigned int status, ret = 0; + + status = UART_GET_CSR(port); + + /* + * The control signals are active low. + */ + if (!(status & AT91_US_DCD)) + ret |= TIOCM_CD; + if (!(status & AT91_US_CTS)) + ret |= TIOCM_CTS; + if (!(status & AT91_US_DSR)) + ret |= TIOCM_DSR; + if (!(status & AT91_US_RI)) + ret |= TIOCM_RI; + + return ret; +} + +/* + * Stop transmitting. + */ +static void at91_stop_tx(struct uart_port *port) +{ + UART_PUT_IDR(port, AT91_US_TXRDY); + port->read_status_mask &= ~AT91_US_TXRDY; +} + +/* + * Start transmitting. + */ +static void at91_start_tx(struct uart_port *port) +{ + port->read_status_mask |= AT91_US_TXRDY; + UART_PUT_IER(port, AT91_US_TXRDY); +} + +/* + * Stop receiving - port is in process of being closed. + */ +static void at91_stop_rx(struct uart_port *port) +{ + UART_PUT_IDR(port, AT91_US_RXRDY); +} + +/* + * Enable modem status interrupts + */ +static void at91_enable_ms(struct uart_port *port) +{ + port->read_status_mask |= (AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC); + UART_PUT_IER(port, AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC); +} + +/* + * Control the transmission of a break signal + */ +static void at91_break_ctl(struct uart_port *port, int break_state) +{ + if (break_state != 0) + UART_PUT_CR(port, AT91_US_STTBRK); /* start break */ + else + UART_PUT_CR(port, AT91_US_STPBRK); /* stop break */ +} + +/* + * Characters received (called from interrupt handler) + */ +static void at91_rx_chars(struct uart_port *port, struct pt_regs *regs) +{ + struct tty_struct *tty = port->info->tty; + unsigned int status, ch, flg; + + status = UART_GET_CSR(port) & port->read_status_mask; + while (status & (AT91_US_RXRDY)) { + ch = UART_GET_CHAR(port); + + if (tty->flip.count >= TTY_FLIPBUF_SIZE) + goto ignore_char; + port->icount.rx++; + + flg = TTY_NORMAL; + + /* + * note that the error handling code is + * out of the main execution path + */ + if (unlikely(status & (AT91_US_PARE | AT91_US_FRAME | AT91_US_OVRE))) { + UART_PUT_CR(port, AT91_US_RSTSTA); /* clear error */ + if (status & (AT91_US_PARE)) + port->icount.parity++; + if (status & (AT91_US_FRAME)) + port->icount.frame++; + if (status & (AT91_US_OVRE)) + port->icount.overrun++; + + if (status & AT91_US_PARE) + flg = TTY_PARITY; + else if (status & AT91_US_FRAME) + flg = TTY_FRAME; + if (status & AT91_US_OVRE) { + /* + * overrun does *not* affect the character + * we read from the FIFO + */ + tty_insert_flip_char(tty, ch, flg); + ch = 0; + flg = TTY_OVERRUN; + } +#ifdef SUPPORT_SYSRQ + port->sysrq = 0; +#endif + } + + if (uart_handle_sysrq_char(port, ch, regs)) + goto ignore_char; + + tty_insert_flip_char(tty, ch, flg); + + ignore_char: + status = UART_GET_CSR(port) & port->read_status_mask; + } + + tty_flip_buffer_push(tty); +} + +/* + * Transmit characters (called from interrupt handler) + */ +static void at91_tx_chars(struct uart_port *port) +{ + struct circ_buf *xmit = &port->info->xmit; + + if (port->x_char) { + UART_PUT_CHAR(port, port->x_char); + port->icount.tx++; + port->x_char = 0; + return; + } + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + at91_stop_tx(port); + return; + } + + while (UART_GET_CSR(port) & AT91_US_TXRDY) { + UART_PUT_CHAR(port, xmit->buf[xmit->tail]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + if (uart_circ_empty(xmit)) + break; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (uart_circ_empty(xmit)) + at91_stop_tx(port); +} + +/* + * Interrupt handler + */ +static irqreturn_t at91_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + struct uart_port *port = dev_id; + unsigned int status, pending, pass_counter = 0; + + status = UART_GET_CSR(port); + pending = status & port->read_status_mask; + if (pending) { + do { + if (pending & AT91_US_RXRDY) + at91_rx_chars(port, regs); + + /* Clear the relevent break bits */ + if (pending & AT91_US_RXBRK) { + UART_PUT_CR(port, AT91_US_RSTSTA); + port->icount.brk++; + uart_handle_break(port); + } + + // TODO: All reads to CSR will clear these interrupts! + if (pending & AT91_US_RIIC) port->icount.rng++; + if (pending & AT91_US_DSRIC) port->icount.dsr++; + if (pending & AT91_US_DCDIC) + uart_handle_dcd_change(port, !(status & AT91_US_DCD)); + if (pending & AT91_US_CTSIC) + uart_handle_cts_change(port, !(status & AT91_US_CTS)); + if (pending & (AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC)) + wake_up_interruptible(&port->info->delta_msr_wait); + + if (pending & AT91_US_TXRDY) + at91_tx_chars(port); + if (pass_counter++ > AT91_ISR_PASS_LIMIT) + break; + + status = UART_GET_CSR(port); + pending = status & port->read_status_mask; + } while (pending); + } + return IRQ_HANDLED; +} + +/* + * Perform initialization and enable port for reception + */ +static int at91_startup(struct uart_port *port) +{ + int retval; + + /* + * Ensure that no interrupts are enabled otherwise when + * request_irq() is called we could get stuck trying to + * handle an unexpected interrupt + */ + UART_PUT_IDR(port, -1); + + /* + * Allocate the IRQ + */ + retval = request_irq(port->irq, at91_interrupt, SA_SHIRQ, "at91_serial", port); + if (retval) { + printk("at91_serial: at91_startup - Can't get irq\n"); + return retval; + } + + /* + * If there is a specific "open" function (to register + * control line interrupts) + */ + if (at91_open) { + retval = at91_open(port); + if (retval) { + free_irq(port->irq, port); + return retval; + } + } + + port->read_status_mask = AT91_US_RXRDY | AT91_US_TXRDY | AT91_US_OVRE + | AT91_US_FRAME | AT91_US_PARE | AT91_US_RXBRK; + /* + * Finally, enable the serial port + */ + UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX); + UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN); /* enable xmit & rcvr */ + UART_PUT_IER(port, AT91_US_RXRDY); /* do receive only */ + return 0; +} + +/* + * Disable the port + */ +static void at91_shutdown(struct uart_port *port) +{ + /* + * Disable all interrupts, port and break condition. + */ + UART_PUT_CR(port, AT91_US_RSTSTA); + UART_PUT_IDR(port, -1); + + /* + * Free the interrupt + */ + free_irq(port->irq, port); + + /* + * If there is a specific "close" function (to unregister + * control line interrupts) + */ + if (at91_close) + at91_close(port); +} + +/* + * Power / Clock management. + */ +static void at91_serial_pm(struct uart_port *port, unsigned int state, unsigned int oldstate) +{ + switch (state) { + case 0: + /* + * Enable the peripheral clock for this serial port. + * This is called on uart_open() or a resume event. + */ + at91_sys_write(AT91_PMC_PCER, 1 << port->irq); + break; + case 3: + /* + * Disable the peripheral clock for this serial port. + * This is called on uart_close() or a suspend event. + */ + if (port->irq != AT91_ID_SYS) /* is this a shared clock? */ + at91_sys_write(AT91_PMC_PCDR, 1 << port->irq); + break; + default: + printk(KERN_ERR "at91_serial: unknown pm %d\n", state); + } +} + +/* + * Change the port parameters + */ +static void at91_set_termios(struct uart_port *port, struct termios * termios, struct termios * old) +{ + unsigned long flags; + unsigned int mode, imr, quot, baud; + + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); + quot = uart_get_divisor(port, baud); + + /* Get current mode register */ + mode = UART_GET_MR(port) & ~(AT91_US_CHRL | AT91_US_NBSTOP | AT91_US_PAR); + + /* byte size */ + switch (termios->c_cflag & CSIZE) { + case CS5: + mode |= AT91_US_CHRL_5; + break; + case CS6: + mode |= AT91_US_CHRL_6; + break; + case CS7: + mode |= AT91_US_CHRL_7; + break; + default: + mode |= AT91_US_CHRL_8; + break; + } + + /* stop bits */ + if (termios->c_cflag & CSTOPB) + mode |= AT91_US_NBSTOP_2; + + /* parity */ + if (termios->c_cflag & PARENB) { + if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */ + if (termios->c_cflag & PARODD) + mode |= AT91_US_PAR_MARK; + else + mode |= AT91_US_PAR_SPACE; + } + else if (termios->c_cflag & PARODD) + mode |= AT91_US_PAR_ODD; + else + mode |= AT91_US_PAR_EVEN; + } + else + mode |= AT91_US_PAR_NONE; + + spin_lock_irqsave(&port->lock, flags); + + port->read_status_mask |= AT91_US_OVRE; + if (termios->c_iflag & INPCK) + port->read_status_mask |= AT91_US_FRAME | AT91_US_PARE; + if (termios->c_iflag & (BRKINT | PARMRK)) + port->read_status_mask |= AT91_US_RXBRK; + + /* + * Characters to ignore + */ + port->ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= (AT91_US_FRAME | AT91_US_PARE); + if (termios->c_iflag & IGNBRK) { + port->ignore_status_mask |= AT91_US_RXBRK; + /* + * If we're ignoring parity and break indicators, + * ignore overruns too (for real raw support). + */ + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= AT91_US_OVRE; + } + + // TODO: Ignore all characters if CREAD is set. + + /* update the per-port timeout */ + uart_update_timeout(port, termios->c_cflag, baud); + + /* disable interrupts and drain transmitter */ + imr = UART_GET_IMR(port); /* get interrupt mask */ + UART_PUT_IDR(port, -1); /* disable all interrupts */ + while (!(UART_GET_CSR(port) & AT91_US_TXEMPTY)) { barrier(); } + + /* disable receiver and transmitter */ + UART_PUT_CR(port, AT91_US_TXDIS | AT91_US_RXDIS); + + /* set the parity, stop bits and data size */ + UART_PUT_MR(port, mode); + + /* set the baud rate */ + UART_PUT_BRGR(port, quot); + UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX); + UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN); + + /* restore interrupts */ + UART_PUT_IER(port, imr); + + /* CTS flow-control and modem-status interrupts */ + if (UART_ENABLE_MS(port, termios->c_cflag)) + port->ops->enable_ms(port); + + spin_unlock_irqrestore(&port->lock, flags); +} + +/* + * Return string describing the specified port + */ +static const char *at91_type(struct uart_port *port) +{ + return (port->type == PORT_AT91RM9200) ? "AT91_SERIAL" : NULL; +} + +/* + * Release the memory region(s) being used by 'port'. + */ +static void at91_release_port(struct uart_port *port) +{ + release_mem_region(port->mapbase, + (port->mapbase == AT91_VA_BASE_DBGU) ? 512 : SZ_16K); +} + +/* + * Request the memory region(s) being used by 'port'. + */ +static int at91_request_port(struct uart_port *port) +{ + return request_mem_region(port->mapbase, + (port->mapbase == AT91_VA_BASE_DBGU) ? 512 : SZ_16K, + "at91_serial") != NULL ? 0 : -EBUSY; + +} + +/* + * Configure/autoconfigure the port. + */ +static void at91_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) { + port->type = PORT_AT91RM9200; + at91_request_port(port); + } +} + +/* + * Verify the new serial_struct (for TIOCSSERIAL). + */ +static int at91_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + int ret = 0; + if (ser->type != PORT_UNKNOWN && ser->type != PORT_AT91RM9200) + ret = -EINVAL; + if (port->irq != ser->irq) + ret = -EINVAL; + if (ser->io_type != SERIAL_IO_MEM) + ret = -EINVAL; + if (port->uartclk / 16 != ser->baud_base) + ret = -EINVAL; + if ((void *)port->mapbase != ser->iomem_base) + ret = -EINVAL; + if (port->iobase != ser->port) + ret = -EINVAL; + if (ser->hub6 != 0) + ret = -EINVAL; + return ret; +} + +static struct uart_ops at91_pops = { + .tx_empty = at91_tx_empty, + .set_mctrl = at91_set_mctrl, + .get_mctrl = at91_get_mctrl, + .stop_tx = at91_stop_tx, + .start_tx = at91_start_tx, + .stop_rx = at91_stop_rx, + .enable_ms = at91_enable_ms, + .break_ctl = at91_break_ctl, + .startup = at91_startup, + .shutdown = at91_shutdown, + .set_termios = at91_set_termios, + .type = at91_type, + .release_port = at91_release_port, + .request_port = at91_request_port, + .config_port = at91_config_port, + .verify_port = at91_verify_port, + .pm = at91_serial_pm, +}; + +static struct uart_port at91_ports[AT91_NR_UART]; + +void __init at91_init_ports(void) +{ + static int first = 1; + int i; + + if (!first) + return; + first = 0; + + for (i = 0; i < AT91_NR_UART; i++) { + at91_ports[i].iotype = UPIO_MEM; + at91_ports[i].flags = UPF_BOOT_AUTOCONF; + at91_ports[i].uartclk = at91_master_clock; + at91_ports[i].ops = &at91_pops; + at91_ports[i].fifosize = 1; + at91_ports[i].line = i; + } +} + +void __init at91_register_uart_fns(struct at91rm9200_port_fns *fns) +{ + if (fns->enable_ms) + at91_pops.enable_ms = fns->enable_ms; + if (fns->get_mctrl) + at91_pops.get_mctrl = fns->get_mctrl; + if (fns->set_mctrl) + at91_pops.set_mctrl = fns->set_mctrl; + at91_open = fns->open; + at91_close = fns->close; + at91_pops.pm = fns->pm; + at91_pops.set_wake = fns->set_wake; +} + +/* + * Setup ports. + */ +void __init at91_register_uart(int idx, int port) +{ + if ((idx < 0) || (idx >= AT91_NR_UART)) { + printk(KERN_ERR "%s: bad index number %d\n", __FUNCTION__, idx); + return; + } + + switch (port) { + case 0: + at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US0; + at91_ports[idx].mapbase = AT91_VA_BASE_US0; + at91_ports[idx].irq = AT91_ID_US0; + AT91_CfgPIO_USART0(); + break; + case 1: + at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US1; + at91_ports[idx].mapbase = AT91_VA_BASE_US1; + at91_ports[idx].irq = AT91_ID_US1; + AT91_CfgPIO_USART1(); + break; + case 2: + at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US2; + at91_ports[idx].mapbase = AT91_VA_BASE_US2; + at91_ports[idx].irq = AT91_ID_US2; + AT91_CfgPIO_USART2(); + break; + case 3: + at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US3; + at91_ports[idx].mapbase = AT91_VA_BASE_US3; + at91_ports[idx].irq = AT91_ID_US3; + AT91_CfgPIO_USART3(); + break; + case 4: + at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_DBGU; + at91_ports[idx].mapbase = AT91_VA_BASE_DBGU; + at91_ports[idx].irq = AT91_ID_SYS; + AT91_CfgPIO_DBGU(); + break; + default: + printk(KERN_ERR "%s : bad port number %d\n", __FUNCTION__, port); + } +} + +#ifdef CONFIG_SERIAL_AT91_CONSOLE + +/* + * Interrupts are disabled on entering + */ +static void at91_console_write(struct console *co, const char *s, u_int count) +{ + struct uart_port *port = at91_ports + co->index; + unsigned int status, i, imr; + + /* + * First, save IMR and then disable interrupts + */ + imr = UART_GET_IMR(port); /* get interrupt mask */ + UART_PUT_IDR(port, AT91_US_RXRDY | AT91_US_TXRDY); + + /* + * Now, do each character + */ + for (i = 0; i < count; i++) { + do { + status = UART_GET_CSR(port); + } while (!(status & AT91_US_TXRDY)); + UART_PUT_CHAR(port, s[i]); + if (s[i] == '\n') { + do { + status = UART_GET_CSR(port); + } while (!(status & AT91_US_TXRDY)); + UART_PUT_CHAR(port, '\r'); + } + } + + /* + * Finally, wait for transmitter to become empty + * and restore IMR + */ + do { + status = UART_GET_CSR(port); + } while (!(status & AT91_US_TXRDY)); + UART_PUT_IER(port, imr); /* set interrupts back the way they were */ +} + +/* + * If the port was already initialised (eg, by a boot loader), try to determine + * the current setup. + */ +static void __init at91_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits) +{ + unsigned int mr, quot; + +// TODO: CR is a write-only register +// unsigned int cr; +// +// cr = UART_GET_CR(port) & (AT91_US_RXEN | AT91_US_TXEN); +// if (cr == (AT91_US_RXEN | AT91_US_TXEN)) { +// /* ok, the port was enabled */ +// } + + mr = UART_GET_MR(port) & AT91_US_CHRL; + if (mr == AT91_US_CHRL_8) + *bits = 8; + else + *bits = 7; + + mr = UART_GET_MR(port) & AT91_US_PAR; + if (mr == AT91_US_PAR_EVEN) + *parity = 'e'; + else if (mr == AT91_US_PAR_ODD) + *parity = 'o'; + + quot = UART_GET_BRGR(port); + *baud = port->uartclk / (16 * (quot)); +} + +static int __init at91_console_setup(struct console *co, char *options) +{ + struct uart_port *port; + int baud = 115200; + 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. + */ + port = uart_get_console(at91_ports, AT91_NR_UART, co); + + /* + * Enable the serial console, in-case bootloader did not do it. + */ + at91_sys_write(AT91_PMC_PCER, 1 << port->irq); /* enable clock */ + UART_PUT_IDR(port, -1); /* disable interrupts */ + UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX); + UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN); + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + else + at91_console_get_options(port, &baud, &parity, &bits); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct uart_driver at91_uart; + +static struct console at91_console = { + .name = AT91_DEVICENAME, + .write = at91_console_write, + .device = uart_console_device, + .setup = at91_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &at91_uart, +}; + +#define AT91_CONSOLE_DEVICE &at91_console + +static int __init at91_console_init(void) +{ + at91_init_ports(); + + at91_console.index = at91_console_port; + register_console(&at91_console); + return 0; +} +console_initcall(at91_console_init); + +#else +#define AT91_CONSOLE_DEVICE NULL +#endif + +static struct uart_driver at91_uart = { + .owner = THIS_MODULE, + .driver_name = AT91_DEVICENAME, + .dev_name = AT91_DEVICENAME, + .devfs_name = AT91_DEVICENAME, + .major = SERIAL_AT91_MAJOR, + .minor = MINOR_START, + .nr = AT91_NR_UART, + .cons = AT91_CONSOLE_DEVICE, +}; + +static int __init at91_serial_init(void) +{ + int ret, i; + + at91_init_ports(); + + ret = uart_register_driver(&at91_uart); + if (ret) + return ret; + + for (i = 0; i < AT91_NR_UART; i++) { + if (at91_serial_map[i] >= 0) + uart_add_one_port(&at91_uart, &at91_ports[i]); + } + + return 0; +} + +static void __exit at91_serial_exit(void) +{ + int i; + + for (i = 0; i < AT91_NR_UART; i++) { + if (at91_serial_map[i] >= 0) + uart_remove_one_port(&at91_uart, &at91_ports[i]); + } + + uart_unregister_driver(&at91_uart); +} + +module_init(at91_serial_init); +module_exit(at91_serial_exit); + +MODULE_AUTHOR("Rick Bronson"); +MODULE_DESCRIPTION("AT91 generic serial port driver"); +MODULE_LICENSE("GPL"); |
