diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/tty/serial/netx-serial.c | 733 |
1 files changed, 733 insertions, 0 deletions
diff --git a/drivers/tty/serial/netx-serial.c b/drivers/tty/serial/netx-serial.c new file mode 100644 index 000000000..b35568634 --- /dev/null +++ b/drivers/tty/serial/netx-serial.c @@ -0,0 +1,733 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix + */ + +#if defined(CONFIG_SERIAL_NETX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/console.h> +#include <linux/sysrq.h> +#include <linux/platform_device.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/serial_core.h> +#include <linux/serial.h> + +#include <asm/io.h> +#include <asm/irq.h> +#include <mach/hardware.h> +#include <mach/netx-regs.h> + +/* We've been assigned a range on the "Low-density serial ports" major */ +#define SERIAL_NX_MAJOR 204 +#define MINOR_START 170 + +enum uart_regs { + UART_DR = 0x00, + UART_SR = 0x04, + UART_LINE_CR = 0x08, + UART_BAUDDIV_MSB = 0x0c, + UART_BAUDDIV_LSB = 0x10, + UART_CR = 0x14, + UART_FR = 0x18, + UART_IIR = 0x1c, + UART_ILPR = 0x20, + UART_RTS_CR = 0x24, + UART_RTS_LEAD = 0x28, + UART_RTS_TRAIL = 0x2c, + UART_DRV_ENABLE = 0x30, + UART_BRM_CR = 0x34, + UART_RXFIFO_IRQLEVEL = 0x38, + UART_TXFIFO_IRQLEVEL = 0x3c, +}; + +#define SR_FE (1<<0) +#define SR_PE (1<<1) +#define SR_BE (1<<2) +#define SR_OE (1<<3) + +#define LINE_CR_BRK (1<<0) +#define LINE_CR_PEN (1<<1) +#define LINE_CR_EPS (1<<2) +#define LINE_CR_STP2 (1<<3) +#define LINE_CR_FEN (1<<4) +#define LINE_CR_5BIT (0<<5) +#define LINE_CR_6BIT (1<<5) +#define LINE_CR_7BIT (2<<5) +#define LINE_CR_8BIT (3<<5) +#define LINE_CR_BITS_MASK (3<<5) + +#define CR_UART_EN (1<<0) +#define CR_SIREN (1<<1) +#define CR_SIRLP (1<<2) +#define CR_MSIE (1<<3) +#define CR_RIE (1<<4) +#define CR_TIE (1<<5) +#define CR_RTIE (1<<6) +#define CR_LBE (1<<7) + +#define FR_CTS (1<<0) +#define FR_DSR (1<<1) +#define FR_DCD (1<<2) +#define FR_BUSY (1<<3) +#define FR_RXFE (1<<4) +#define FR_TXFF (1<<5) +#define FR_RXFF (1<<6) +#define FR_TXFE (1<<7) + +#define IIR_MIS (1<<0) +#define IIR_RIS (1<<1) +#define IIR_TIS (1<<2) +#define IIR_RTIS (1<<3) +#define IIR_MASK 0xf + +#define RTS_CR_AUTO (1<<0) +#define RTS_CR_RTS (1<<1) +#define RTS_CR_COUNT (1<<2) +#define RTS_CR_MOD2 (1<<3) +#define RTS_CR_RTS_POL (1<<4) +#define RTS_CR_CTS_CTR (1<<5) +#define RTS_CR_CTS_POL (1<<6) +#define RTS_CR_STICK (1<<7) + +#define UART_PORT_SIZE 0x40 +#define DRIVER_NAME "netx-uart" + +struct netx_port { + struct uart_port port; +}; + +static void netx_stop_tx(struct uart_port *port) +{ + unsigned int val; + val = readl(port->membase + UART_CR); + writel(val & ~CR_TIE, port->membase + UART_CR); +} + +static void netx_stop_rx(struct uart_port *port) +{ + unsigned int val; + val = readl(port->membase + UART_CR); + writel(val & ~CR_RIE, port->membase + UART_CR); +} + +static void netx_enable_ms(struct uart_port *port) +{ + unsigned int val; + val = readl(port->membase + UART_CR); + writel(val | CR_MSIE, port->membase + UART_CR); +} + +static inline void netx_transmit_buffer(struct uart_port *port) +{ + struct circ_buf *xmit = &port->state->xmit; + + if (port->x_char) { + writel(port->x_char, port->membase + UART_DR); + port->icount.tx++; + port->x_char = 0; + return; + } + + if (uart_tx_stopped(port) || uart_circ_empty(xmit)) { + netx_stop_tx(port); + return; + } + + do { + /* send xmit->buf[xmit->tail] + * out the port here */ + writel(xmit->buf[xmit->tail], port->membase + UART_DR); + xmit->tail = (xmit->tail + 1) & + (UART_XMIT_SIZE - 1); + port->icount.tx++; + if (uart_circ_empty(xmit)) + break; + } while (!(readl(port->membase + UART_FR) & FR_TXFF)); + + if (uart_circ_empty(xmit)) + netx_stop_tx(port); +} + +static void netx_start_tx(struct uart_port *port) +{ + writel( + readl(port->membase + UART_CR) | CR_TIE, port->membase + UART_CR); + + if (!(readl(port->membase + UART_FR) & FR_TXFF)) + netx_transmit_buffer(port); +} + +static unsigned int netx_tx_empty(struct uart_port *port) +{ + return readl(port->membase + UART_FR) & FR_BUSY ? 0 : TIOCSER_TEMT; +} + +static void netx_txint(struct uart_port *port) +{ + struct circ_buf *xmit = &port->state->xmit; + + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + netx_stop_tx(port); + return; + } + + netx_transmit_buffer(port); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); +} + +static void netx_rxint(struct uart_port *port, unsigned long *flags) +{ + unsigned char rx, flg, status; + + while (!(readl(port->membase + UART_FR) & FR_RXFE)) { + rx = readl(port->membase + UART_DR); + flg = TTY_NORMAL; + port->icount.rx++; + status = readl(port->membase + UART_SR); + if (status & SR_BE) { + writel(0, port->membase + UART_SR); + if (uart_handle_break(port)) + continue; + } + + if (unlikely(status & (SR_FE | SR_PE | SR_OE))) { + + if (status & SR_PE) + port->icount.parity++; + else if (status & SR_FE) + port->icount.frame++; + if (status & SR_OE) + port->icount.overrun++; + + status &= port->read_status_mask; + + if (status & SR_BE) + flg = TTY_BREAK; + else if (status & SR_PE) + flg = TTY_PARITY; + else if (status & SR_FE) + flg = TTY_FRAME; + } + + if (uart_handle_sysrq_char(port, rx)) + continue; + + uart_insert_char(port, status, SR_OE, rx, flg); + } + + spin_unlock_irqrestore(&port->lock, *flags); + tty_flip_buffer_push(&port->state->port); + spin_lock_irqsave(&port->lock, *flags); +} + +static irqreturn_t netx_int(int irq, void *dev_id) +{ + struct uart_port *port = dev_id; + unsigned long flags; + unsigned char status; + + spin_lock_irqsave(&port->lock,flags); + + status = readl(port->membase + UART_IIR) & IIR_MASK; + while (status) { + if (status & IIR_RIS) + netx_rxint(port, &flags); + if (status & IIR_TIS) + netx_txint(port); + if (status & IIR_MIS) { + if (readl(port->membase + UART_FR) & FR_CTS) + uart_handle_cts_change(port, 1); + else + uart_handle_cts_change(port, 0); + } + writel(0, port->membase + UART_IIR); + status = readl(port->membase + UART_IIR) & IIR_MASK; + } + + spin_unlock_irqrestore(&port->lock,flags); + return IRQ_HANDLED; +} + +static unsigned int netx_get_mctrl(struct uart_port *port) +{ + unsigned int ret = TIOCM_DSR | TIOCM_CAR; + + if (readl(port->membase + UART_FR) & FR_CTS) + ret |= TIOCM_CTS; + + return ret; +} + +static void netx_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + unsigned int val; + + /* FIXME: Locking needed ? */ + if (mctrl & TIOCM_RTS) { + val = readl(port->membase + UART_RTS_CR); + writel(val | RTS_CR_RTS, port->membase + UART_RTS_CR); + } +} + +static void netx_break_ctl(struct uart_port *port, int break_state) +{ + unsigned int line_cr; + spin_lock_irq(&port->lock); + + line_cr = readl(port->membase + UART_LINE_CR); + if (break_state != 0) + line_cr |= LINE_CR_BRK; + else + line_cr &= ~LINE_CR_BRK; + writel(line_cr, port->membase + UART_LINE_CR); + + spin_unlock_irq(&port->lock); +} + +static int netx_startup(struct uart_port *port) +{ + int ret; + + ret = request_irq(port->irq, netx_int, 0, + DRIVER_NAME, port); + if (ret) { + dev_err(port->dev, "unable to grab irq%d\n",port->irq); + goto exit; + } + + writel(readl(port->membase + UART_LINE_CR) | LINE_CR_FEN, + port->membase + UART_LINE_CR); + + writel(CR_MSIE | CR_RIE | CR_TIE | CR_RTIE | CR_UART_EN, + port->membase + UART_CR); + +exit: + return ret; +} + +static void netx_shutdown(struct uart_port *port) +{ + writel(0, port->membase + UART_CR) ; + + free_irq(port->irq, port); +} + +static void +netx_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + unsigned int baud, quot; + unsigned char old_cr; + unsigned char line_cr = LINE_CR_FEN; + unsigned char rts_cr = 0; + + switch (termios->c_cflag & CSIZE) { + case CS5: + line_cr |= LINE_CR_5BIT; + break; + case CS6: + line_cr |= LINE_CR_6BIT; + break; + case CS7: + line_cr |= LINE_CR_7BIT; + break; + case CS8: + line_cr |= LINE_CR_8BIT; + break; + } + + if (termios->c_cflag & CSTOPB) + line_cr |= LINE_CR_STP2; + + if (termios->c_cflag & PARENB) { + line_cr |= LINE_CR_PEN; + if (!(termios->c_cflag & PARODD)) + line_cr |= LINE_CR_EPS; + } + + if (termios->c_cflag & CRTSCTS) + rts_cr = RTS_CR_AUTO | RTS_CR_CTS_CTR | RTS_CR_RTS_POL; + + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); + quot = baud * 4096; + quot /= 1000; + quot *= 256; + quot /= 100000; + + spin_lock_irq(&port->lock); + + uart_update_timeout(port, termios->c_cflag, baud); + + old_cr = readl(port->membase + UART_CR); + + /* disable interrupts */ + writel(old_cr & ~(CR_MSIE | CR_RIE | CR_TIE | CR_RTIE), + port->membase + UART_CR); + + /* drain transmitter */ + while (readl(port->membase + UART_FR) & FR_BUSY); + + /* disable UART */ + writel(old_cr & ~CR_UART_EN, port->membase + UART_CR); + + /* modem status interrupts */ + old_cr &= ~CR_MSIE; + if (UART_ENABLE_MS(port, termios->c_cflag)) + old_cr |= CR_MSIE; + + writel((quot>>8) & 0xff, port->membase + UART_BAUDDIV_MSB); + writel(quot & 0xff, port->membase + UART_BAUDDIV_LSB); + writel(line_cr, port->membase + UART_LINE_CR); + + writel(rts_cr, port->membase + UART_RTS_CR); + + /* + * Characters to ignore + */ + port->ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= SR_PE; + if (termios->c_iflag & IGNBRK) { + port->ignore_status_mask |= SR_BE; + /* + * If we're ignoring parity and break indicators, + * ignore overruns too (for real raw support). + */ + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= SR_PE; + } + + port->read_status_mask = 0; + if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) + port->read_status_mask |= SR_BE; + if (termios->c_iflag & INPCK) + port->read_status_mask |= SR_PE | SR_FE; + + writel(old_cr, port->membase + UART_CR); + + spin_unlock_irq(&port->lock); +} + +static const char *netx_type(struct uart_port *port) +{ + return port->type == PORT_NETX ? "NETX" : NULL; +} + +static void netx_release_port(struct uart_port *port) +{ + release_mem_region(port->mapbase, UART_PORT_SIZE); +} + +static int netx_request_port(struct uart_port *port) +{ + return request_mem_region(port->mapbase, UART_PORT_SIZE, + DRIVER_NAME) != NULL ? 0 : -EBUSY; +} + +static void netx_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE && netx_request_port(port) == 0) + port->type = PORT_NETX; +} + +static int +netx_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + int ret = 0; + + if (ser->type != PORT_UNKNOWN && ser->type != PORT_NETX) + ret = -EINVAL; + + return ret; +} + +static struct uart_ops netx_pops = { + .tx_empty = netx_tx_empty, + .set_mctrl = netx_set_mctrl, + .get_mctrl = netx_get_mctrl, + .stop_tx = netx_stop_tx, + .start_tx = netx_start_tx, + .stop_rx = netx_stop_rx, + .enable_ms = netx_enable_ms, + .break_ctl = netx_break_ctl, + .startup = netx_startup, + .shutdown = netx_shutdown, + .set_termios = netx_set_termios, + .type = netx_type, + .release_port = netx_release_port, + .request_port = netx_request_port, + .config_port = netx_config_port, + .verify_port = netx_verify_port, +}; + +static struct netx_port netx_ports[] = { + { + .port = { + .type = PORT_NETX, + .iotype = UPIO_MEM, + .membase = (char __iomem *)io_p2v(NETX_PA_UART0), + .mapbase = NETX_PA_UART0, + .irq = NETX_IRQ_UART0, + .uartclk = 100000000, + .fifosize = 16, + .flags = UPF_BOOT_AUTOCONF, + .ops = &netx_pops, + .line = 0, + }, + }, { + .port = { + .type = PORT_NETX, + .iotype = UPIO_MEM, + .membase = (char __iomem *)io_p2v(NETX_PA_UART1), + .mapbase = NETX_PA_UART1, + .irq = NETX_IRQ_UART1, + .uartclk = 100000000, + .fifosize = 16, + .flags = UPF_BOOT_AUTOCONF, + .ops = &netx_pops, + .line = 1, + }, + }, { + .port = { + .type = PORT_NETX, + .iotype = UPIO_MEM, + .membase = (char __iomem *)io_p2v(NETX_PA_UART2), + .mapbase = NETX_PA_UART2, + .irq = NETX_IRQ_UART2, + .uartclk = 100000000, + .fifosize = 16, + .flags = UPF_BOOT_AUTOCONF, + .ops = &netx_pops, + .line = 2, + }, + } +}; + +#ifdef CONFIG_SERIAL_NETX_CONSOLE + +static void netx_console_putchar(struct uart_port *port, int ch) +{ + while (readl(port->membase + UART_FR) & FR_BUSY); + writel(ch, port->membase + UART_DR); +} + +static void +netx_console_write(struct console *co, const char *s, unsigned int count) +{ + struct uart_port *port = &netx_ports[co->index].port; + unsigned char cr_save; + + cr_save = readl(port->membase + UART_CR); + writel(cr_save | CR_UART_EN, port->membase + UART_CR); + + uart_console_write(port, s, count, netx_console_putchar); + + while (readl(port->membase + UART_FR) & FR_BUSY); + writel(cr_save, port->membase + UART_CR); +} + +static void __init +netx_console_get_options(struct uart_port *port, int *baud, + int *parity, int *bits, int *flow) +{ + unsigned char line_cr; + + *baud = (readl(port->membase + UART_BAUDDIV_MSB) << 8) | + readl(port->membase + UART_BAUDDIV_LSB); + *baud *= 1000; + *baud /= 4096; + *baud *= 1000; + *baud /= 256; + *baud *= 100; + + line_cr = readl(port->membase + UART_LINE_CR); + *parity = 'n'; + if (line_cr & LINE_CR_PEN) { + if (line_cr & LINE_CR_EPS) + *parity = 'e'; + else + *parity = 'o'; + } + + switch (line_cr & LINE_CR_BITS_MASK) { + case LINE_CR_8BIT: + *bits = 8; + break; + case LINE_CR_7BIT: + *bits = 7; + break; + case LINE_CR_6BIT: + *bits = 6; + break; + case LINE_CR_5BIT: + *bits = 5; + break; + } + + if (readl(port->membase + UART_RTS_CR) & RTS_CR_AUTO) + *flow = 'r'; +} + +static int __init +netx_console_setup(struct console *co, char *options) +{ + struct netx_port *sport; + 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 == -1 || co->index >= ARRAY_SIZE(netx_ports)) + co->index = 0; + sport = &netx_ports[co->index]; + + if (options) { + uart_parse_options(options, &baud, &parity, &bits, &flow); + } else { + /* if the UART is enabled, assume it has been correctly setup + * by the bootloader and get the options + */ + if (readl(sport->port.membase + UART_CR) & CR_UART_EN) { + netx_console_get_options(&sport->port, &baud, + &parity, &bits, &flow); + } + + } + + return uart_set_options(&sport->port, co, baud, parity, bits, flow); +} + +static struct uart_driver netx_reg; +static struct console netx_console = { + .name = "ttyNX", + .write = netx_console_write, + .device = uart_console_device, + .setup = netx_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &netx_reg, +}; + +static int __init netx_console_init(void) +{ + register_console(&netx_console); + return 0; +} +console_initcall(netx_console_init); + +#define NETX_CONSOLE &netx_console +#else +#define NETX_CONSOLE NULL +#endif + +static struct uart_driver netx_reg = { + .owner = THIS_MODULE, + .driver_name = DRIVER_NAME, + .dev_name = "ttyNX", + .major = SERIAL_NX_MAJOR, + .minor = MINOR_START, + .nr = ARRAY_SIZE(netx_ports), + .cons = NETX_CONSOLE, +}; + +static int serial_netx_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct netx_port *sport = platform_get_drvdata(pdev); + + if (sport) + uart_suspend_port(&netx_reg, &sport->port); + + return 0; +} + +static int serial_netx_resume(struct platform_device *pdev) +{ + struct netx_port *sport = platform_get_drvdata(pdev); + + if (sport) + uart_resume_port(&netx_reg, &sport->port); + + return 0; +} + +static int serial_netx_probe(struct platform_device *pdev) +{ + struct uart_port *port = &netx_ports[pdev->id].port; + + dev_info(&pdev->dev, "initialising\n"); + + port->dev = &pdev->dev; + + writel(1, port->membase + UART_RXFIFO_IRQLEVEL); + uart_add_one_port(&netx_reg, &netx_ports[pdev->id].port); + platform_set_drvdata(pdev, &netx_ports[pdev->id]); + + return 0; +} + +static int serial_netx_remove(struct platform_device *pdev) +{ + struct netx_port *sport = platform_get_drvdata(pdev); + + if (sport) + uart_remove_one_port(&netx_reg, &sport->port); + + return 0; +} + +static struct platform_driver serial_netx_driver = { + .probe = serial_netx_probe, + .remove = serial_netx_remove, + + .suspend = serial_netx_suspend, + .resume = serial_netx_resume, + + .driver = { + .name = DRIVER_NAME, + }, +}; + +static int __init netx_serial_init(void) +{ + int ret; + + printk(KERN_INFO "Serial: NetX driver\n"); + + ret = uart_register_driver(&netx_reg); + if (ret) + return ret; + + ret = platform_driver_register(&serial_netx_driver); + if (ret != 0) + uart_unregister_driver(&netx_reg); + + return 0; +} + +static void __exit netx_serial_exit(void) +{ + platform_driver_unregister(&serial_netx_driver); + uart_unregister_driver(&netx_reg); +} + +module_init(netx_serial_init); +module_exit(netx_serial_exit); + +MODULE_AUTHOR("Sascha Hauer"); +MODULE_DESCRIPTION("NetX serial port driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); |