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path: root/drivers/tty/serial/bcm63xx_uart.c
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Diffstat (limited to 'drivers/tty/serial/bcm63xx_uart.c')
-rw-r--r--drivers/tty/serial/bcm63xx_uart.c263
1 files changed, 142 insertions, 121 deletions
diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
index 6fa2ae77fffd..51df9d2d8bfc 100644
--- a/drivers/tty/serial/bcm63xx_uart.c
+++ b/drivers/tty/serial/bcm63xx_uart.c
@@ -1,8 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0
/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
* Derived from many drivers using generic_serial interface.
*
* Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
@@ -13,10 +10,6 @@
* my board.
*/
-#if defined(CONFIG_SERIAL_BCM63XX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
-#define SUPPORT_SYSRQ
-#endif
-
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/init.h>
@@ -29,10 +22,9 @@
#include <linux/sysrq.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
-
-#include <bcm63xx_irq.h>
-#include <bcm63xx_regs.h>
-#include <bcm63xx_io.h>
+#include <linux/serial_bcm63xx.h>
+#include <linux/io.h>
+#include <linux/of.h>
#define BCM63XX_NR_UARTS 2
@@ -81,13 +73,13 @@ static struct uart_port ports[BCM63XX_NR_UARTS];
static inline unsigned int bcm_uart_readl(struct uart_port *port,
unsigned int offset)
{
- return bcm_readl(port->membase + offset);
+ return __raw_readl(port->membase + offset);
}
static inline void bcm_uart_writel(struct uart_port *port,
unsigned int value, unsigned int offset)
{
- bcm_writel(value, port->membase + offset);
+ __raw_writel(value, port->membase + offset);
}
/*
@@ -209,7 +201,7 @@ static void bcm_uart_break_ctl(struct uart_port *port, int ctl)
unsigned long flags;
unsigned int val;
- spin_lock_irqsave(&port->lock, flags);
+ uart_port_lock_irqsave(port, &flags);
val = bcm_uart_readl(port, UART_CTL_REG);
if (ctl)
@@ -218,7 +210,7 @@ static void bcm_uart_break_ctl(struct uart_port *port, int ctl)
val &= ~UART_CTL_XMITBRK_MASK;
bcm_uart_writel(port, val, UART_CTL_REG);
- spin_unlock_irqrestore(&port->lock, flags);
+ uart_port_unlock_irqrestore(port, flags);
}
/*
@@ -293,10 +285,9 @@ static void bcm_uart_do_rx(struct uart_port *port)
flag = TTY_PARITY;
}
- if (uart_handle_sysrq_char(port, c))
+ if (uart_prepare_sysrq_char(port, c))
continue;
-
if ((cstat & port->ignore_status_mask) == 0)
tty_insert_flip_char(tty_port, c, flag);
@@ -311,53 +302,27 @@ static void bcm_uart_do_rx(struct uart_port *port)
*/
static void bcm_uart_do_tx(struct uart_port *port)
{
- struct circ_buf *xmit;
- unsigned int val, max_count;
-
- if (port->x_char) {
- bcm_uart_writel(port, port->x_char, UART_FIFO_REG);
- port->icount.tx++;
- port->x_char = 0;
- return;
- }
-
- if (uart_tx_stopped(port)) {
- bcm_uart_stop_tx(port);
- return;
- }
-
- xmit = &port->state->xmit;
- if (uart_circ_empty(xmit))
- goto txq_empty;
+ unsigned int val;
+ bool pending;
+ u8 ch;
val = bcm_uart_readl(port, UART_MCTL_REG);
val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
- max_count = port->fifosize - val;
-
- while (max_count--) {
- unsigned int c;
-
- c = xmit->buf[xmit->tail];
- bcm_uart_writel(port, c, UART_FIFO_REG);
- 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))
- goto txq_empty;
- return;
+ pending = uart_port_tx_limited_flags(port, ch, UART_TX_NOSTOP,
+ port->fifosize - val,
+ true,
+ bcm_uart_writel(port, ch, UART_FIFO_REG),
+ ({}));
+ if (pending)
+ return;
-txq_empty:
/* nothing to send, disable transmit interrupt */
val = bcm_uart_readl(port, UART_IR_REG);
val &= ~UART_TX_INT_MASK;
bcm_uart_writel(port, val, UART_IR_REG);
- return;
+
+ if (uart_tx_stopped(port))
+ bcm_uart_stop_tx(port);
}
/*
@@ -369,7 +334,7 @@ static irqreturn_t bcm_uart_interrupt(int irq, void *dev_id)
unsigned int irqstat;
port = dev_id;
- spin_lock(&port->lock);
+ uart_port_lock(port);
irqstat = bcm_uart_readl(port, UART_IR_REG);
if (irqstat & UART_RX_INT_STAT)
@@ -390,7 +355,7 @@ static irqreturn_t bcm_uart_interrupt(int irq, void *dev_id)
estat & UART_EXTINP_DCD_MASK);
}
- spin_unlock(&port->lock);
+ uart_unlock_and_check_sysrq(port);
return IRQ_HANDLED;
}
@@ -473,7 +438,7 @@ static int bcm_uart_startup(struct uart_port *port)
/* register irq and enable rx interrupts */
ret = request_irq(port->irq, bcm_uart_interrupt, 0,
- bcm_uart_type(port), port);
+ dev_name(port->dev), port);
if (ret)
return ret;
bcm_uart_writel(port, UART_RX_INT_MASK, UART_IR_REG);
@@ -488,9 +453,9 @@ static void bcm_uart_shutdown(struct uart_port *port)
{
unsigned long flags;
- spin_lock_irqsave(&port->lock, flags);
+ uart_port_lock_irqsave(port, &flags);
bcm_uart_writel(port, 0, UART_IR_REG);
- spin_unlock_irqrestore(&port->lock, flags);
+ uart_port_unlock_irqrestore(port, flags);
bcm_uart_disable(port);
bcm_uart_flush(port);
@@ -500,14 +465,18 @@ static void bcm_uart_shutdown(struct uart_port *port)
/*
* serial core request to change current uart setting
*/
-static void bcm_uart_set_termios(struct uart_port *port,
- struct ktermios *new,
- struct ktermios *old)
+static void bcm_uart_set_termios(struct uart_port *port, struct ktermios *new,
+ const struct ktermios *old)
{
unsigned int ctl, baud, quot, ier;
unsigned long flags;
+ int tries;
- spin_lock_irqsave(&port->lock, flags);
+ uart_port_lock_irqsave(port, &flags);
+
+ /* Drain the hot tub fully before we power it off for the winter. */
+ for (tries = 3; !bcm_uart_tx_empty(port) && tries; tries--)
+ mdelay(10);
/* disable uart while changing speed */
bcm_uart_disable(port);
@@ -566,7 +535,7 @@ static void bcm_uart_set_termios(struct uart_port *port,
port->read_status_mask |= UART_FIFO_FRAMEERR_MASK;
port->read_status_mask |= UART_FIFO_PARERR_MASK;
}
- if (new->c_iflag & (BRKINT))
+ if (new->c_iflag & (IGNBRK | BRKINT))
port->read_status_mask |= UART_FIFO_BRKDET_MASK;
port->ignore_status_mask = 0;
@@ -579,7 +548,7 @@ static void bcm_uart_set_termios(struct uart_port *port,
uart_update_timeout(port, new->c_cflag, baud);
bcm_uart_enable(port);
- spin_unlock_irqrestore(&port->lock, flags);
+ uart_port_unlock_irqrestore(port, flags);
}
/*
@@ -587,20 +556,7 @@ static void bcm_uart_set_termios(struct uart_port *port,
*/
static int bcm_uart_request_port(struct uart_port *port)
{
- unsigned int size;
-
- size = RSET_UART_SIZE;
- if (!request_mem_region(port->mapbase, size, "bcm63xx")) {
- dev_err(port->dev, "Memory region busy\n");
- return -EBUSY;
- }
-
- port->membase = ioremap(port->mapbase, size);
- if (!port->membase) {
- dev_err(port->dev, "Unable to map registers\n");
- release_mem_region(port->mapbase, size);
- return -EBUSY;
- }
+ /* UARTs always present */
return 0;
}
@@ -609,8 +565,7 @@ static int bcm_uart_request_port(struct uart_port *port)
*/
static void bcm_uart_release_port(struct uart_port *port)
{
- release_mem_region(port->mapbase, RSET_UART_SIZE);
- iounmap(port->membase);
+ /* Nothing to release ... */
}
/*
@@ -643,8 +598,42 @@ static int bcm_uart_verify_port(struct uart_port *port,
return 0;
}
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * return true when outstanding tx equals fifo size
+ */
+static bool bcm_uart_tx_full(struct uart_port *port)
+{
+ unsigned int val;
+
+ val = bcm_uart_readl(port, UART_MCTL_REG);
+ val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
+ return !(port->fifosize - val);
+}
+
+static int bcm_uart_poll_get_char(struct uart_port *port)
+{
+ unsigned int iestat;
+
+ iestat = bcm_uart_readl(port, UART_IR_REG);
+ if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY)))
+ return NO_POLL_CHAR;
+
+ return bcm_uart_readl(port, UART_FIFO_REG);
+}
+
+static void bcm_uart_poll_put_char(struct uart_port *port, unsigned char c)
+{
+ while (bcm_uart_tx_full(port)) {
+ cpu_relax();
+ }
+
+ bcm_uart_writel(port, c, UART_FIFO_REG);
+}
+#endif
+
/* serial core callbacks */
-static struct uart_ops bcm_uart_ops = {
+static const struct uart_ops bcm_uart_ops = {
.tx_empty = bcm_uart_tx_empty,
.get_mctrl = bcm_uart_get_mctrl,
.set_mctrl = bcm_uart_set_mctrl,
@@ -661,12 +650,16 @@ static struct uart_ops bcm_uart_ops = {
.request_port = bcm_uart_request_port,
.config_port = bcm_uart_config_port,
.verify_port = bcm_uart_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = bcm_uart_poll_get_char,
+ .poll_put_char = bcm_uart_poll_put_char,
+#endif
};
#ifdef CONFIG_SERIAL_BCM63XX_CONSOLE
-static inline void wait_for_xmitr(struct uart_port *port)
+static void wait_for_xmitr(struct uart_port *port)
{
unsigned int tmout;
@@ -698,7 +691,7 @@ static inline void wait_for_xmitr(struct uart_port *port)
/*
* output given char
*/
-static void bcm_console_putchar(struct uart_port *port, int ch)
+static void bcm_console_putchar(struct uart_port *port, unsigned char ch)
{
wait_for_xmitr(port);
bcm_uart_writel(port, ch, UART_FIFO_REG);
@@ -712,20 +705,14 @@ static void bcm_console_write(struct console *co, const char *s,
{
struct uart_port *port;
unsigned long flags;
- int locked;
+ int locked = 1;
port = &ports[co->index];
- local_irq_save(flags);
- if (port->sysrq) {
- /* bcm_uart_interrupt() already took the lock */
- locked = 0;
- } else if (oops_in_progress) {
- locked = spin_trylock(&port->lock);
- } else {
- spin_lock(&port->lock);
- locked = 1;
- }
+ if (oops_in_progress)
+ locked = uart_port_trylock_irqsave(port, &flags);
+ else
+ uart_port_lock_irqsave(port, &flags);
/* call helper to deal with \r\n */
uart_console_write(port, s, count, bcm_console_putchar);
@@ -734,8 +721,7 @@ static void bcm_console_write(struct console *co, const char *s,
wait_for_xmitr(port);
if (locked)
- spin_unlock(&port->lock);
- local_irq_restore(flags);
+ uart_port_unlock_irqrestore(port, flags);
}
/*
@@ -781,6 +767,26 @@ static int __init bcm63xx_console_init(void)
console_initcall(bcm63xx_console_init);
+static void bcm_early_write(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, bcm_console_putchar);
+ wait_for_xmitr(&dev->port);
+}
+
+static int __init bcm_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = bcm_early_write;
+ return 0;
+}
+
+OF_EARLYCON_DECLARE(bcm63xx_uart, "brcm,bcm6345-uart", bcm_early_console_setup);
+
#define BCM63XX_CONSOLE (&bcm63xx_console)
#else
#define BCM63XX_CONSOLE NULL
@@ -801,72 +807,87 @@ static struct uart_driver bcm_uart_driver = {
*/
static int bcm_uart_probe(struct platform_device *pdev)
{
- struct resource *res_mem, *res_irq;
+ struct resource *res_mem;
struct uart_port *port;
struct clk *clk;
int ret;
+ if (pdev->dev.of_node) {
+ pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
+
+ if (pdev->id < 0)
+ pdev->id = of_alias_get_id(pdev->dev.of_node, "uart");
+ }
+
if (pdev->id < 0 || pdev->id >= BCM63XX_NR_UARTS)
return -EINVAL;
- if (ports[pdev->id].membase)
+ port = &ports[pdev->id];
+ if (port->membase)
return -EBUSY;
+ memset(port, 0, sizeof(*port));
- res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res_mem)
- return -ENODEV;
+ port->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res_mem);
+ if (IS_ERR(port->membase))
+ return PTR_ERR(port->membase);
+ port->mapbase = res_mem->start;
- res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (!res_irq)
- return -ENODEV;
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ return ret;
+ port->irq = ret;
+
+ clk = clk_get(&pdev->dev, "refclk");
+ if (IS_ERR(clk) && pdev->dev.of_node)
+ clk = of_clk_get(pdev->dev.of_node, 0);
- clk = clk_get(&pdev->dev, "periph");
if (IS_ERR(clk))
return -ENODEV;
- port = &ports[pdev->id];
- memset(port, 0, sizeof(*port));
port->iotype = UPIO_MEM;
- port->mapbase = res_mem->start;
- port->irq = res_irq->start;
port->ops = &bcm_uart_ops;
port->flags = UPF_BOOT_AUTOCONF;
port->dev = &pdev->dev;
port->fifosize = 16;
port->uartclk = clk_get_rate(clk) / 2;
port->line = pdev->id;
+ port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_BCM63XX_CONSOLE);
clk_put(clk);
ret = uart_add_one_port(&bcm_uart_driver, port);
if (ret) {
- ports[pdev->id].membase = 0;
+ ports[pdev->id].membase = NULL;
return ret;
}
platform_set_drvdata(pdev, port);
return 0;
}
-static int bcm_uart_remove(struct platform_device *pdev)
+static void bcm_uart_remove(struct platform_device *pdev)
{
struct uart_port *port;
port = platform_get_drvdata(pdev);
uart_remove_one_port(&bcm_uart_driver, port);
- platform_set_drvdata(pdev, NULL);
/* mark port as free */
- ports[pdev->id].membase = 0;
- return 0;
+ ports[pdev->id].membase = NULL;
}
+static const struct of_device_id bcm63xx_of_match[] = {
+ { .compatible = "brcm,bcm6345-uart" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, bcm63xx_of_match);
+
/*
* platform driver stuff
*/
static struct platform_driver bcm_uart_platform_driver = {
.probe = bcm_uart_probe,
- .remove = bcm_uart_remove,
+ .remove = bcm_uart_remove,
.driver = {
- .owner = THIS_MODULE,
.name = "bcm63xx_uart",
+ .of_match_table = bcm63xx_of_match,
},
};
@@ -895,5 +916,5 @@ module_init(bcm_uart_init);
module_exit(bcm_uart_exit);
MODULE_AUTHOR("Maxime Bizon <mbizon@freebox.fr>");
-MODULE_DESCRIPTION("Broadcom 63<xx integrated uart driver");
+MODULE_DESCRIPTION("Broadcom 63xx integrated uart driver");
MODULE_LICENSE("GPL");