serial: remove tile uart driver

The tile architecture is getting removed, and this driver is
useless without it.
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

drivers/tty/serial/Kconfig

@@ -1330,15 +1330,6 @@ config SERIAL_EFM32_UART_CONSOLE
 	depends on SERIAL_EFM32_UART=y
 	select SERIAL_CORE_CONSOLE
 
-config SERIAL_TILEGX
-	tristate "TILE-Gx on-chip serial port support"
-	depends on TILEGX
-	select TILE_GXIO_UART
-	select SERIAL_CORE
-	---help---
-	  This device provides access to the on-chip UARTs on the TILE-Gx
-	  processor.
-
 config SERIAL_ARC
 	tristate "ARC UART driver support"
 	select SERIAL_CORE

drivers/tty/serial/Makefile

@@ -63,7 +63,6 @@ obj-$(CONFIG_SERIAL_KS8695) += serial_ks8695.o
 obj-$(CONFIG_SERIAL_OMAP) += omap-serial.o
 obj-$(CONFIG_SERIAL_ALTERA_UART) += altera_uart.o
 obj-$(CONFIG_SERIAL_ST_ASC) += st-asc.o
-obj-$(CONFIG_SERIAL_TILEGX) += tilegx.o
 obj-$(CONFIG_SERIAL_QE) += ucc_uart.o
 obj-$(CONFIG_SERIAL_TIMBERDALE)	+= timbuart.o
 obj-$(CONFIG_SERIAL_GRLIB_GAISLER_APBUART) += apbuart.o

drivers/tty/serial/tilegx.c

-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright 2013 Tilera Corporation. All Rights Reserved.
- *
- * TILEGx UART driver.
- */
-
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/irq.h>
-#include <linux/module.h>
-#include <linux/serial_core.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-
-#include <gxio/common.h>
-#include <gxio/iorpc_globals.h>
-#include <gxio/iorpc_uart.h>
-#include <gxio/kiorpc.h>
-
-#include <hv/drv_uart_intf.h>
-
-/*
- * Use device name ttyS, major 4, minor 64-65.
- * This is the usual serial port name, 8250 conventional range.
- */
-#define TILEGX_UART_MAJOR	TTY_MAJOR
-#define TILEGX_UART_MINOR	64
-#define TILEGX_UART_NAME	"ttyS"
-#define DRIVER_NAME_STRING	"TILEGx_Serial"
-#define TILEGX_UART_REF_CLK	125000000; /* REF_CLK is always 125 MHz. */
-
-struct tile_uart_port {
-	/* UART port. */
-	struct uart_port	uart;
-
-	/* GXIO device context. */
-	gxio_uart_context_t	context;
-
-	/* UART access mutex. */
-	struct mutex		mutex;
-
-	/* CPU receiving interrupts. */
-	int			irq_cpu;
-};
-
-static struct tile_uart_port tile_uart_ports[TILEGX_UART_NR];
-static struct uart_driver tilegx_uart_driver;
-
-
-/*
- * Read UART rx fifo, and insert the chars into tty buffer.
- */
-static void receive_chars(struct tile_uart_port *tile_uart,
-			  struct tty_struct *tty)
-{
-	int i;
-	char c;
-	UART_FIFO_COUNT_t count;
-	gxio_uart_context_t *context = &tile_uart->context;
-	struct tty_port *port = tty->port;
-
-	count.word = gxio_uart_read(context, UART_FIFO_COUNT);
-	for (i = 0; i < count.rfifo_count; i++) {
-		c = (char)gxio_uart_read(context, UART_RECEIVE_DATA);
-		tty_insert_flip_char(port, c, TTY_NORMAL);
-	}
-}
-
-
-/*
- * Drain the Rx FIFO, called by interrupt handler.
- */
-static void handle_receive(struct tile_uart_port *tile_uart)
-{
-	struct tty_port *port = &tile_uart->uart.state->port;
-	struct tty_struct *tty = tty_port_tty_get(port);
-	gxio_uart_context_t *context = &tile_uart->context;
-
-	if (!tty)
-		return;
-
-	/* First read UART rx fifo. */
-	receive_chars(tile_uart, tty);
-
-	/* Reset RFIFO_WE interrupt. */
-	gxio_uart_write(context, UART_INTERRUPT_STATUS,
-			UART_INTERRUPT_MASK__RFIFO_WE_MASK);
-
-	/* Final read, if any chars comes between the first read and
-	 * the interrupt reset.
-	 */
-	receive_chars(tile_uart, tty);
-
-	spin_unlock(&tile_uart->uart.lock);
-	tty_flip_buffer_push(port);
-	spin_lock(&tile_uart->uart.lock);
-	tty_kref_put(tty);
-}
-
-
-/*
- * Push one char to UART Write FIFO.
- * Return 0 on success, -1 if write filo is full.
- */
-static int tilegx_putchar(gxio_uart_context_t *context, char c)
-{
-	UART_FLAG_t flag;
-	flag.word = gxio_uart_read(context, UART_FLAG);
-	if (flag.wfifo_full)
-		return -1;
-
-	gxio_uart_write(context, UART_TRANSMIT_DATA, (unsigned long)c);
-	return 0;
-}
-
-
-/*
- * Send chars to UART Write FIFO; called by interrupt handler.
- */
-static void handle_transmit(struct tile_uart_port *tile_uart)
-{
-	unsigned char ch;
-	struct uart_port *port;
-	struct circ_buf *xmit;
-	gxio_uart_context_t *context = &tile_uart->context;
-
-	/* First reset WFIFO_RE interrupt. */
-	gxio_uart_write(context, UART_INTERRUPT_STATUS,
-			UART_INTERRUPT_MASK__WFIFO_RE_MASK);
-
-	port = &tile_uart->uart;
-	xmit = &port->state->xmit;
-	if (port->x_char) {
-		if (tilegx_putchar(context, port->x_char))
-			return;
-		port->x_char = 0;
-		port->icount.tx++;
-	}
-
-	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
-		return;
-
-	while (!uart_circ_empty(xmit)) {
-		ch = xmit->buf[xmit->tail];
-		if (tilegx_putchar(context, ch))
-			break;
-		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
-		port->icount.tx++;
-	}
-
-	/* Reset WFIFO_RE interrupt. */
-	gxio_uart_write(context, UART_INTERRUPT_STATUS,
-			UART_INTERRUPT_MASK__WFIFO_RE_MASK);
-
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
-		uart_write_wakeup(port);
-}
-
-
-/*
- * UART Interrupt handler.
- */
-static irqreturn_t tilegx_interrupt(int irq, void *dev_id)
-{
-	unsigned long flags;
-	UART_INTERRUPT_STATUS_t intr_stat;
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-	struct uart_port *port = dev_id;
-	irqreturn_t ret = IRQ_NONE;
-
-	spin_lock_irqsave(&port->lock, flags);
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	context = &tile_uart->context;
-	intr_stat.word = gxio_uart_read(context, UART_INTERRUPT_STATUS);
-
-	if (intr_stat.rfifo_we) {
-		handle_receive(tile_uart);
-		ret = IRQ_HANDLED;
-	}
-	if (intr_stat.wfifo_re) {
-		handle_transmit(tile_uart);
-		ret = IRQ_HANDLED;
-	}
-
-	spin_unlock_irqrestore(&port->lock, flags);
-	return ret;
-}
-
-
-/*
- * Return TIOCSER_TEMT when transmitter FIFO is empty.
- */
-static u_int tilegx_tx_empty(struct uart_port *port)
-{
-	int ret;
-	UART_FLAG_t flag;
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	if (!mutex_trylock(&tile_uart->mutex))
-		return 0;
-	context = &tile_uart->context;
-
-	flag.word = gxio_uart_read(context, UART_FLAG);
-	ret = (flag.wfifo_empty) ? TIOCSER_TEMT : 0;
-	mutex_unlock(&tile_uart->mutex);
-
-	return ret;
-}
-
-
-/*
- * Set state of the modem control output lines.
- */
-static void tilegx_set_mctrl(struct uart_port *port, u_int mctrl)
-{
-	/* N/A */
-}
-
-
-/*
- * Get state of the modem control input lines.
- */
-static u_int tilegx_get_mctrl(struct uart_port *port)
-{
-	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
-}
-
-
-/*
- * Stop transmitting.
- */
-static void tilegx_stop_tx(struct uart_port *port)
-{
-	/* N/A */
-}
-
-
-/*
- * Start transmitting.
- */
-static void tilegx_start_tx(struct uart_port *port)
-{
-	unsigned char ch;
-	struct circ_buf *xmit;
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	if (!mutex_trylock(&tile_uart->mutex))
-		return;
-	context = &tile_uart->context;
-	xmit = &port->state->xmit;
-	if (port->x_char) {
-		if (tilegx_putchar(context, port->x_char))
-			return;
-		port->x_char = 0;
-		port->icount.tx++;
-	}
-
-	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
-		mutex_unlock(&tile_uart->mutex);
-		return;
-	}
-
-	while (!uart_circ_empty(xmit)) {
-		ch = xmit->buf[xmit->tail];
-		if (tilegx_putchar(context, ch))
-			break;
-		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
-		port->icount.tx++;
-	}
-
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
-		uart_write_wakeup(port);
-
-	mutex_unlock(&tile_uart->mutex);
-}
-
-
-/*
- * Stop receiving - port is in process of being closed.
- */
-static void tilegx_stop_rx(struct uart_port *port)
-{
-	int err;
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-	int cpu;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	if (!mutex_trylock(&tile_uart->mutex))
-		return;
-
-	context = &tile_uart->context;
-	cpu = tile_uart->irq_cpu;
-	err = gxio_uart_cfg_interrupt(context, cpu_x(cpu), cpu_y(cpu),
-				      KERNEL_PL, -1);
-	mutex_unlock(&tile_uart->mutex);
-}
-
-/*
- * Control the transmission of a break signal.
- */
-static void tilegx_break_ctl(struct uart_port *port, int break_state)
-{
-	/* N/A */
-}
-
-
-/*
- * Perform initialization and enable port for reception.
- */
-static int tilegx_startup(struct uart_port *port)
-{
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-	int ret = 0;
-	int cpu = raw_smp_processor_id();  /* pick an arbitrary cpu */
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	if (mutex_lock_interruptible(&tile_uart->mutex))
-		return -EBUSY;
-	context = &tile_uart->context;
-
-	/* Now open the hypervisor device if we haven't already. */
-	if (context->fd < 0) {
-		UART_INTERRUPT_MASK_t intr_mask;
-
-		/* Initialize UART device. */
-		ret = gxio_uart_init(context, port->line);
-		if (ret) {
-			ret = -ENXIO;
-			goto err;
-		}
-
-		/* Create our IRQs. */
-		port->irq = irq_alloc_hwirq(-1);
-		if (!port->irq)
-			goto err_uart_dest;
-		tile_irq_activate(port->irq, TILE_IRQ_PERCPU);
-
-		/* Register our IRQs. */
-		ret = request_irq(port->irq, tilegx_interrupt, 0,
-				  tilegx_uart_driver.driver_name, port);
-		if (ret)
-			goto err_dest_irq;
-
-		/* Request that the hardware start sending us interrupts. */
-		tile_uart->irq_cpu = cpu;
-		ret = gxio_uart_cfg_interrupt(context, cpu_x(cpu), cpu_y(cpu),
-					      KERNEL_PL, port->irq);
-		if (ret)
-			goto err_free_irq;
-
-		/* Enable UART Tx/Rx Interrupt. */
-		intr_mask.word = gxio_uart_read(context, UART_INTERRUPT_MASK);
-		intr_mask.wfifo_re = 0;
-		intr_mask.rfifo_we = 0;
-		gxio_uart_write(context, UART_INTERRUPT_MASK, intr_mask.word);
-
-		/* Reset the Tx/Rx interrupt in case it's set. */
-		gxio_uart_write(context, UART_INTERRUPT_STATUS,
-				UART_INTERRUPT_MASK__WFIFO_RE_MASK |
-				UART_INTERRUPT_MASK__RFIFO_WE_MASK);
-	}
-
-	mutex_unlock(&tile_uart->mutex);
-	return ret;
-
-err_free_irq:
-	free_irq(port->irq, port);
-err_dest_irq:
-	irq_free_hwirq(port->irq);
-err_uart_dest:
-	gxio_uart_destroy(context);
-	ret = -ENXIO;
-err:
-	mutex_unlock(&tile_uart->mutex);
-	return ret;
-}
-
-
-/*
- * Release kernel resources if it is the last close, disable the port,
- * free IRQ and close the port.
- */
-static void tilegx_shutdown(struct uart_port *port)
-{
-	int err;
-	UART_INTERRUPT_MASK_t intr_mask;
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-	int cpu;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	if (mutex_lock_interruptible(&tile_uart->mutex))
-		return;
-	context = &tile_uart->context;
-
-	/* Disable UART Tx/Rx Interrupt. */
-	intr_mask.word = gxio_uart_read(context, UART_INTERRUPT_MASK);
-	intr_mask.wfifo_re = 1;
-	intr_mask.rfifo_we = 1;
-	gxio_uart_write(context, UART_INTERRUPT_MASK, intr_mask.word);
-
-	/* Request that the hardware stop sending us interrupts. */
-	cpu = tile_uart->irq_cpu;
-	err = gxio_uart_cfg_interrupt(context, cpu_x(cpu), cpu_y(cpu),
-				      KERNEL_PL, -1);
-
-	if (port->irq > 0) {
-		free_irq(port->irq, port);
-		irq_free_hwirq(port->irq);
-		port->irq = 0;
-	}
-
-	gxio_uart_destroy(context);
-
-	mutex_unlock(&tile_uart->mutex);
-}
-
-
-/*
- * Flush the buffer.
- */
-static void tilegx_flush_buffer(struct uart_port *port)
-{
-	/* N/A */
-}
-
-
-/*
- * Change the port parameters.
- */
-static void tilegx_set_termios(struct uart_port *port,
-			       struct ktermios *termios, struct ktermios *old)
-{
-	int err;
-	UART_DIVISOR_t divisor;
-	UART_TYPE_t type;
-	unsigned int baud;
-	struct tile_uart_port *tile_uart;
-	gxio_uart_context_t *context;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	if (!mutex_trylock(&tile_uart->mutex))
-		return;
-	context = &tile_uart->context;
-
-	/* Open the hypervisor device if we haven't already. */
-	if (context->fd < 0) {
-		err = gxio_uart_init(context, port->line);
-		if (err) {
-			mutex_unlock(&tile_uart->mutex);
-			return;
-		}
-	}
-
-	divisor.word = gxio_uart_read(context, UART_DIVISOR);
-	type.word = gxio_uart_read(context, UART_TYPE);
-
-	/* Divisor. */
-	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
-	divisor.divisor = uart_get_divisor(port, baud);
-
-	/* Byte size. */
-	if ((termios->c_cflag & CSIZE) == CS7)
-		type.dbits = UART_TYPE__DBITS_VAL_SEVEN_DBITS;
-	else
-		type.dbits = UART_TYPE__DBITS_VAL_EIGHT_DBITS;
-
-	/* Parity. */
-	if (termios->c_cflag & PARENB) {
-		/* Mark or Space parity. */
-		if (termios->c_cflag & CMSPAR)
-			if (termios->c_cflag & PARODD)
-				type.ptype = UART_TYPE__PTYPE_VAL_MARK;
-			else
-				type.ptype = UART_TYPE__PTYPE_VAL_SPACE;
-		else if (termios->c_cflag & PARODD)
-			type.ptype = UART_TYPE__PTYPE_VAL_ODD;
-		else
-			type.ptype = UART_TYPE__PTYPE_VAL_EVEN;
-	} else
-		type.ptype = UART_TYPE__PTYPE_VAL_NONE;
-
-	/* Stop bits. */
-	if (termios->c_cflag & CSTOPB)
-		type.sbits = UART_TYPE__SBITS_VAL_TWO_SBITS;
-	else
-		type.sbits = UART_TYPE__SBITS_VAL_ONE_SBITS;
-
-	/* Set the uart paramters. */
-	gxio_uart_write(context, UART_DIVISOR, divisor.word);
-	gxio_uart_write(context, UART_TYPE, type.word);
-
-	mutex_unlock(&tile_uart->mutex);
-}
-
-
-/*
- * Return string describing the specified port.
- */
-static const char *tilegx_type(struct uart_port *port)
-{
-	return port->type == PORT_TILEGX ? DRIVER_NAME_STRING : NULL;
-}
-
-
-/*
- * Release the resources being used by 'port'.
- */
-static void tilegx_release_port(struct uart_port *port)
-{
-	/* Nothing to release. */
-}
-
-
-/*
- * Request the resources being used by 'port'.
- */
-static int tilegx_request_port(struct uart_port *port)
-{
-	/* Always present. */
-	return 0;
-}
-
-
-/*
- * Configure/autoconfigure the port.
- */
-static void tilegx_config_port(struct uart_port *port, int flags)
-{
-	if (flags & UART_CONFIG_TYPE)
-		port->type = PORT_TILEGX;
-}
-
-
-/*
- * Verify the new serial_struct (for TIOCSSERIAL).
- */
-static int tilegx_verify_port(struct uart_port *port,
-			      struct serial_struct *ser)
-{
-	if ((ser->type != PORT_UNKNOWN) && (ser->type != PORT_TILEGX))
-		return -EINVAL;
-
-	return 0;
-}
-
-#ifdef CONFIG_CONSOLE_POLL
-
-/*
- * Console polling routines for writing and reading from the uart while
- * in an interrupt or debug context.
- */
-
-static int tilegx_poll_get_char(struct uart_port *port)
-{
-	UART_FIFO_COUNT_t count;
-	gxio_uart_context_t *context;
-	struct tile_uart_port *tile_uart;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	context = &tile_uart->context;
-	count.word = gxio_uart_read(context, UART_FIFO_COUNT);
-	if (count.rfifo_count == 0)
-		return NO_POLL_CHAR;
-	return (char)gxio_uart_read(context, UART_RECEIVE_DATA);
-}
-
-static void tilegx_poll_put_char(struct uart_port *port, unsigned char c)
-{
-	gxio_uart_context_t *context;
-	struct tile_uart_port *tile_uart;
-
-	tile_uart = container_of(port, struct tile_uart_port, uart);
-	context = &tile_uart->context;
-	gxio_uart_write(context, UART_TRANSMIT_DATA, (unsigned long)c);
-}
-
-#endif /* CONFIG_CONSOLE_POLL */
-
-
-static const struct uart_ops tilegx_ops = {
-	.tx_empty	= tilegx_tx_empty,
-	.set_mctrl	= tilegx_set_mctrl,
-	.get_mctrl	= tilegx_get_mctrl,
-	.stop_tx	= tilegx_stop_tx,
-	.start_tx	= tilegx_start_tx,
-	.stop_rx	= tilegx_stop_rx,
-	.break_ctl	= tilegx_break_ctl,
-	.startup	= tilegx_startup,
-	.shutdown	= tilegx_shutdown,
-	.flush_buffer	= tilegx_flush_buffer,
-	.set_termios	= tilegx_set_termios,
-	.type		= tilegx_type,
-	.release_port	= tilegx_release_port,
-	.request_port	= tilegx_request_port,
-	.config_port	= tilegx_config_port,
-	.verify_port	= tilegx_verify_port,
-#ifdef CONFIG_CONSOLE_POLL
-	.poll_get_char	= tilegx_poll_get_char,
-	.poll_put_char	= tilegx_poll_put_char,
-#endif
-};
-
-
-static void tilegx_init_ports(void)
-{
-	int i;
-	struct uart_port *port;
-
-	for (i = 0; i < TILEGX_UART_NR; i++) {
-		port = &tile_uart_ports[i].uart;
-		port->ops = &tilegx_ops;
-		port->line = i;
-		port->type = PORT_TILEGX;
-		port->uartclk = TILEGX_UART_REF_CLK;
-		port->flags = UPF_BOOT_AUTOCONF;
-
-		tile_uart_ports[i].context.fd = -1;
-		mutex_init(&tile_uart_ports[i].mutex);
-	}
-}
-
-
-static struct uart_driver tilegx_uart_driver = {
-	.owner		= THIS_MODULE,
-	.driver_name	= DRIVER_NAME_STRING,
-	.dev_name	= TILEGX_UART_NAME,
-	.major		= TILEGX_UART_MAJOR,
-	.minor		= TILEGX_UART_MINOR,
-	.nr		= TILEGX_UART_NR,
-};
-
-
-static int __init tilegx_init(void)
-{
-	int i;
-	int ret;
-	struct tty_driver *tty_drv;
-
-	ret = uart_register_driver(&tilegx_uart_driver);
-	if (ret)
-		return ret;
-	tty_drv = tilegx_uart_driver.tty_driver;
-	tty_drv->init_termios.c_cflag = B115200 | CS8 | CREAD | HUPCL | CLOCAL;
-	tty_drv->init_termios.c_ispeed = 115200;
-	tty_drv->init_termios.c_ospeed = 115200;
-
-	tilegx_init_ports();
-
-	for (i = 0; i < TILEGX_UART_NR; i++) {
-		struct uart_port *port = &tile_uart_ports[i].uart;
-		ret = uart_add_one_port(&tilegx_uart_driver, port);
-	}
-
-	return 0;
-}
-
-
-static void __exit tilegx_exit(void)
-{
-	int i;
-	struct uart_port *port;
-
-	for (i = 0; i < TILEGX_UART_NR; i++) {
-		port = &tile_uart_ports[i].uart;
-		uart_remove_one_port(&tilegx_uart_driver, port);
-	}
-
-	uart_unregister_driver(&tilegx_uart_driver);
-}
-
-
-module_init(tilegx_init);
-module_exit(tilegx_exit);
-
-MODULE_AUTHOR("Tilera Corporation");
-MODULE_DESCRIPTION("TILEGx serial port driver");
-MODULE_LICENSE("GPL");