diff options
Diffstat (limited to 'target/linux/adm5120/files/drivers/serial/adm5120_uart.c')
| -rw-r--r-- | target/linux/adm5120/files/drivers/serial/adm5120_uart.c | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/target/linux/adm5120/files/drivers/serial/adm5120_uart.c b/target/linux/adm5120/files/drivers/serial/adm5120_uart.c new file mode 100644 index 000000000..83c5f7201 --- /dev/null +++ b/target/linux/adm5120/files/drivers/serial/adm5120_uart.c @@ -0,0 +1,520 @@ +/* + * Serial driver for ADM5120 SoC + * + * Derived from drivers/serial/uart00.c + * Copyright 2001 Altera Corporation + * + * Some pieces are derived from the ADMtek 2.4 serial driver. + * Copyright (C) ADMtek Incorporated, 2003 + * daniell@admtek.com.tw + * Which again was derived from drivers/char/serial.c + * Copyright (C) Linus Torvalds et al. + * + * Copyright Jeroen Vreeken (pe1rxq@amsat.org), 2005 + */ + +#include <linux/autoconf.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/console.h> + +#include <asm/mach-adm5120/adm5120_defs.h> +#include <asm/mach-adm5120/adm5120_irq.h> + +#define ADM5120_UART_REG(base, reg) \ + (*(volatile u32 *)KSEG1ADDR((base)+(reg))) + +#define ADM5120_UARTCLK_FREQ 62500000 +#define ADM5120_UART_BAUDDIV(rate) ((unsigned long)(ADM5120_UARTCLK_FREQ/(16*(rate)) - 1)) + +#define ADM5120_UART_BAUD115200 ADM5120_UART_BAUDDIV(115200) + +#define ADM5120_UART_DATA 0x00 +#define ADM5120_UART_RS 0x04 +#define ADM5120_UART_LCR_H 0x08 +#define ADM5120_UART_LCR_M 0x0c +#define ADM5120_UART_LCR_L 0x10 +#define ADM5120_UART_CR 0x14 +#define ADM5120_UART_FR 0x18 +#define ADM5120_UART_IR 0x1c + +#define ADM5120_UART_FE 0x01 +#define ADM5120_UART_PE 0x02 +#define ADM5120_UART_BE 0x04 +#define ADM5120_UART_OE 0x08 +#define ADM5120_UART_ERR 0x0f +#define ADM5120_UART_FIFO_EN 0x10 +#define ADM5120_UART_EN 0x01 +#define ADM5120_UART_TIE 0x20 +#define ADM5120_UART_RIE 0x50 +#define ADM5120_UART_IE 0x78 +#define ADM5120_UART_CTS 0x01 +#define ADM5120_UART_DSR 0x02 +#define ADM5120_UART_DCD 0x04 +#define ADM5120_UART_TXFF 0x20 +#define ADM5120_UART_TXFE 0x80 +#define ADM5120_UART_RXFE 0x10 +#define ADM5120_UART_BRK 0x01 +#define ADM5120_UART_PEN 0x02 +#define ADM5120_UART_EPS 0x04 +#define ADM5120_UART_STP2 0x08 +#define ADM5120_UART_W5 0x00 +#define ADM5120_UART_W6 0x20 +#define ADM5120_UART_W7 0x40 +#define ADM5120_UART_W8 0x60 +#define ADM5120_UART_MIS 0x01 +#define ADM5120_UART_RIS 0x02 +#define ADM5120_UART_TIS 0x04 +#define ADM5120_UART_RTIS 0x08 + +static void adm5120ser_stop_tx(struct uart_port *port) +{ + ADM5120_UART_REG(port->iobase, ADM5120_UART_CR) &= ~ADM5120_UART_TIE; +} + +static void adm5120ser_irq_rx(struct uart_port *port) +{ + struct tty_struct *tty = port->info->tty; + unsigned int status, ch, rds, flg, ignored = 0; + + status = ADM5120_UART_REG(port->iobase, ADM5120_UART_FR); + while (!(status & ADM5120_UART_RXFE)) { + /* + * We need to read rds before reading the + * character from the fifo + */ + rds = ADM5120_UART_REG(port->iobase, ADM5120_UART_RS); + ch = ADM5120_UART_REG(port->iobase, ADM5120_UART_DATA); + port->icount.rx++; + + if (tty->low_latency) + tty_flip_buffer_push(tty); + + flg = TTY_NORMAL; + + /* + * Note that the error handling code is + * out of the main execution path + */ + if (rds & ADM5120_UART_ERR) + goto handle_error; + if (uart_handle_sysrq_char(port, ch)) + goto ignore_char; + + error_return: + tty_insert_flip_char(tty, ch, flg); + + ignore_char: + status = ADM5120_UART_REG(port->iobase, ADM5120_UART_FR); + } + out: + tty_flip_buffer_push(tty); + return; + + handle_error: + ADM5120_UART_REG(port->iobase, ADM5120_UART_RS) = 0xff; + if (rds & ADM5120_UART_BE) { + port->icount.brk++; + if (uart_handle_break(port)) + goto ignore_char; + } else if (rds & ADM5120_UART_PE) + port->icount.parity++; + else if (rds & ADM5120_UART_FE) + port->icount.frame++; + if (rds & ADM5120_UART_OE) + port->icount.overrun++; + + if (rds & port->ignore_status_mask) { + if (++ignored > 100) + goto out; + goto ignore_char; + } + rds &= port->read_status_mask; + + if (rds & ADM5120_UART_BE) + flg = TTY_BREAK; + else if (rds & ADM5120_UART_PE) + flg = TTY_PARITY; + else if (rds & ADM5120_UART_FE) + flg = TTY_FRAME; + + if (rds & ADM5120_UART_OE) { + /* + * CHECK: does overrun affect the current character? + * ASSUMPTION: it does not. + */ + tty_insert_flip_char(tty, ch, flg); + ch = 0; + flg = TTY_OVERRUN; + } +#ifdef CONFIG_MAGIC_SYSRQ + port->sysrq = 0; +#endif + goto error_return; +} + +static void adm5120ser_irq_tx(struct uart_port *port) +{ + struct circ_buf *xmit = &port->info->xmit; + int count; + + if (port->x_char) { + ADM5120_UART_REG(port->iobase, ADM5120_UART_DATA) = + port->x_char; + port->icount.tx++; + port->x_char = 0; + return; + } + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + adm5120ser_stop_tx(port); + return; + } + + count = port->fifosize >> 1; + do { + ADM5120_UART_REG(port->iobase, ADM5120_UART_DATA) = + xmit->buf[xmit->tail]; + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + if (uart_circ_empty(xmit)) + break; + } while (--count > 0); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (uart_circ_empty(xmit)) + adm5120ser_stop_tx(port); +} + +static void adm5120ser_irq_modem(struct uart_port *port) +{ + unsigned int status; + + status = ADM5120_UART_REG(port->iobase, ADM5120_UART_FR); + + if (status & ADM5120_UART_DCD) + uart_handle_dcd_change(port, status & ADM5120_UART_DCD); + + if (status & ADM5120_UART_DSR) + port->icount.dsr++; + + if (status & ADM5120_UART_CTS) + uart_handle_cts_change(port, status & ADM5120_UART_CTS); + + wake_up_interruptible(&port->info->delta_msr_wait); +} + +static irqreturn_t adm5120ser_irq(int irq, void *dev_id) +{ + struct uart_port *port = dev_id; + unsigned long ir = ADM5120_UART_REG(port->iobase, ADM5120_UART_IR); + + if (ir & (ADM5120_UART_RIS | ADM5120_UART_RTIS)) + adm5120ser_irq_rx(port); + if (ir & ADM5120_UART_TIS) + adm5120ser_irq_tx(port); + if (ir & ADM5120_UART_MIS) { + adm5120ser_irq_modem(port); + ADM5120_UART_REG(port->iobase, ADM5120_UART_IR) = 0xff; + } + + return IRQ_HANDLED; +} + +static unsigned int adm5120ser_tx_empty(struct uart_port *port) +{ + unsigned int fr = ADM5120_UART_REG(port->iobase, ADM5120_UART_FR); + return (fr & ADM5120_UART_TXFE) ? TIOCSER_TEMT : 0; +} + +static void adm5120ser_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ +} + +static unsigned int adm5120ser_get_mctrl(struct uart_port *port) +{ + unsigned int result = 0; + unsigned int fr = ADM5120_UART_REG(port->iobase, ADM5120_UART_FR); + + if (fr & ADM5120_UART_CTS) + result |= TIOCM_CTS; + if (fr & ADM5120_UART_DSR) + result |= TIOCM_DSR; + if (fr & ADM5120_UART_DCD) + result |= TIOCM_CAR; + return result; +} + +static void adm5120ser_start_tx(struct uart_port *port) +{ + ADM5120_UART_REG(port->iobase, ADM5120_UART_CR) |= ADM5120_UART_TIE; +} + +static void adm5120ser_stop_rx(struct uart_port *port) +{ + ADM5120_UART_REG(port->iobase, ADM5120_UART_CR) &= ~ADM5120_UART_RIE; +} + +static void adm5120ser_enable_ms(struct uart_port *port) +{ +} + +static void adm5120ser_break_ctl(struct uart_port *port, int break_state) +{ + unsigned long flags; + unsigned long lcrh; + + spin_lock_irqsave(&port->lock, flags); + lcrh = ADM5120_UART_REG(port->iobase, ADM5120_UART_LCR_H); + if (break_state == -1) + lcrh |= ADM5120_UART_BRK; + else + lcrh &= ~ADM5120_UART_BRK; + ADM5120_UART_REG(port->iobase, ADM5120_UART_LCR_H) = lcrh; + spin_unlock_irqrestore(&port->lock, flags); +} + +static int adm5120ser_startup(struct uart_port *port) +{ + int ret; + + ret = request_irq(port->irq, adm5120ser_irq, 0, "ADM5120 UART", port); + if (ret) { + printk(KERN_ERR "Couldn't get irq %d\n", port->irq); + return ret; + } + ADM5120_UART_REG(port->iobase, ADM5120_UART_LCR_H) |= + ADM5120_UART_FIFO_EN; + ADM5120_UART_REG(port->iobase, ADM5120_UART_CR) |= + ADM5120_UART_EN | ADM5120_UART_IE; + return 0; +} + +static void adm5120ser_shutdown(struct uart_port *port) +{ + ADM5120_UART_REG(port->iobase, ADM5120_UART_CR) &= ~ADM5120_UART_IE; + free_irq(port->irq, port); +} + +static void adm5120ser_set_termios(struct uart_port *port, + struct ktermios *termios, struct ktermios *old) +{ + unsigned int baud, quot, lcrh; + unsigned long flags; + + termios->c_cflag |= CREAD; + + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); + quot = uart_get_divisor(port, baud); + + lcrh = ADM5120_UART_FIFO_EN; + switch (termios->c_cflag & CSIZE) { + case CS5: + lcrh |= ADM5120_UART_W5; + break; + case CS6: + lcrh |= ADM5120_UART_W6; + break; + case CS7: + lcrh |= ADM5120_UART_W7; + break; + default: + lcrh |= ADM5120_UART_W8; + break; + } + if (termios->c_cflag & CSTOPB) + lcrh |= ADM5120_UART_STP2; + if (termios->c_cflag & PARENB) { + lcrh |= ADM5120_UART_PEN; + if (!(termios->c_cflag & PARODD)) + lcrh |= ADM5120_UART_EPS; + } + + spin_lock_irqsave(port->lock, flags); + + ADM5120_UART_REG(port->iobase, ADM5120_UART_LCR_H) = lcrh; + + /* + * Update the per-port timeout. + */ + uart_update_timeout(port, termios->c_cflag, baud); + + port->read_status_mask = ADM5120_UART_OE; + if (termios->c_iflag & INPCK) + port->read_status_mask |= ADM5120_UART_FE | ADM5120_UART_PE; + if (termios->c_iflag & (BRKINT | PARMRK)) + port->read_status_mask |= ADM5120_UART_BE; + + /* + * Characters to ignore + */ + port->ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= ADM5120_UART_FE | ADM5120_UART_PE; + if (termios->c_iflag & IGNBRK) { + port->ignore_status_mask |= ADM5120_UART_BE; + /* + * If we're ignoring parity and break indicators, + * ignore overruns to (for real raw support). + */ + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= ADM5120_UART_OE; + } + + quot = ADM5120_UART_BAUD115200; + ADM5120_UART_REG(port->iobase, ADM5120_UART_LCR_L) = quot & 0xff; + ADM5120_UART_REG(port->iobase, ADM5120_UART_LCR_M) = quot >> 8; + + spin_unlock_irqrestore(&port->lock, flags); +} + +static const char *adm5120ser_type(struct uart_port *port) +{ + return port->type == PORT_ADM5120 ? "ADM5120" : NULL; +} + +static void adm5120ser_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) + port->type = PORT_ADM5120; +} + +static void adm5120ser_release_port(struct uart_port *port) +{ + release_mem_region(port->iobase, ADM5120_UART_SIZE); +} + +static int adm5120ser_request_port(struct uart_port *port) +{ + return request_mem_region(port->iobase, ADM5120_UART_SIZE, + "adm5120-uart") != NULL ? 0 : -EBUSY; +} + +static struct uart_ops adm5120ser_ops = { + .tx_empty = adm5120ser_tx_empty, + .set_mctrl = adm5120ser_set_mctrl, + .get_mctrl = adm5120ser_get_mctrl, + .stop_tx = adm5120ser_stop_tx, + .start_tx = adm5120ser_start_tx, + .stop_rx = adm5120ser_stop_rx, + .enable_ms = adm5120ser_enable_ms, + .break_ctl = adm5120ser_break_ctl, + .startup = adm5120ser_startup, + .shutdown = adm5120ser_shutdown, + .set_termios = adm5120ser_set_termios, + .type = adm5120ser_type, + .config_port = adm5120ser_config_port, + .release_port = adm5120ser_release_port, + .request_port = adm5120ser_request_port, +}; + +static void adm5120console_put(const char c) +{ + while ((ADM5120_UART_REG(ADM5120_UART0_BASE, ADM5120_UART_FR) & + ADM5120_UART_TXFF) != 0); + ADM5120_UART_REG(ADM5120_UART0_BASE, ADM5120_UART_DATA) = c; +} + +static void adm5120console_write(struct console *con, const char *s, + unsigned int count) +{ + while (count--) { + if (*s == '\n') + adm5120console_put('\r'); + adm5120console_put(*s); + s++; + } +} + +static int adm5120console_setup(struct console *con, char *options) +{ + /* Set to 115200 baud, 8N1 and enable FIFO */ + ADM5120_UART_REG(ADM5120_UART0_BASE, ADM5120_UART_LCR_L) = + ADM5120_UART_BAUD115200 & 0xff; + ADM5120_UART_REG(ADM5120_UART0_BASE, ADM5120_UART_LCR_M) = + ADM5120_UART_BAUD115200 >> 8; + ADM5120_UART_REG(ADM5120_UART0_BASE, ADM5120_UART_LCR_H) = + ADM5120_UART_W8 | ADM5120_UART_FIFO_EN; + /* Enable port */ + ADM5120_UART_REG(ADM5120_UART0_BASE, ADM5120_UART_CR) = + ADM5120_UART_EN; + + return 0; +} + +static struct uart_driver adm5120ser_reg; + +static struct console adm5120_serconsole = { + .name = "ttyS", + .write = adm5120console_write, + .device = uart_console_device, + .setup = adm5120console_setup, + .flags = CON_PRINTBUFFER, + .cflag = B115200 | CS8 | CREAD, + .index = 0, + .data = &adm5120ser_reg, +}; + +static int __init adm5120console_init(void) +{ + register_console(&adm5120_serconsole); + return 0; +} + +console_initcall(adm5120console_init); + + +static struct uart_port adm5120ser_ports[] = { + { + .iobase = ADM5120_UART0_BASE, + .irq = ADM5120_IRQ_UART0, + .uartclk = ADM5120_UARTCLK_FREQ, + .fifosize = 16, + .ops = &adm5120ser_ops, + .line = 0, + .flags = ASYNC_BOOT_AUTOCONF, + }, +#if (CONFIG_ADM5120_NR_UARTS > 1) + { + .iobase = ADM5120_UART1_BASE, + .irq = ADM5120_IRQ_UART1, + .uartclk = ADM5120_UARTCLK_FREQ, + .fifosize = 16, + .ops = &adm5120ser_ops, + .line = 1, + .flags = ASYNC_BOOT_AUTOCONF, + }, +#endif +}; + +static struct uart_driver adm5120ser_reg = { + .owner = THIS_MODULE, + .driver_name = "ttyS", + .dev_name = "ttyS", + .major = TTY_MAJOR, + .minor = 64, + .nr = CONFIG_ADM5120_NR_UARTS, + .cons = &adm5120_serconsole, +}; + +static int __init adm5120ser_init(void) +{ + int ret, i; + + ret = uart_register_driver(&adm5120ser_reg); + if (!ret) { + for (i = 0; i < CONFIG_ADM5120_NR_UARTS; i++) + uart_add_one_port(&adm5120ser_reg, &adm5120ser_ports[i]); + } + + return ret; +} + +__initcall(adm5120ser_init); |