// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2005 Sascha Hauer , Pengutronix * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation. * * 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 */ #if defined(CONFIG_SERIAL_NETX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) #define SUPPORT_SYSRQ #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 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);