154 lines
5.2 KiB
Diff
154 lines
5.2 KiB
Diff
From c6983dd875db2ab4340af77fca5afdcbb6e92a8a Mon Sep 17 00:00:00 2001
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From: Thomas Gleixner <tglx@linutronix.de>
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Date: Thu, 14 Sep 2023 20:43:50 +0206
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Subject: [PATCH 059/196] serial: lpc32xx_hs: Use port lock wrappers
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When a serial port is used for kernel console output, then all
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modifications to the UART registers which are done from other contexts,
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e.g. getty, termios, are interference points for the kernel console.
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So far this has been ignored and the printk output is based on the
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principle of hope. The rework of the console infrastructure which aims to
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support threaded and atomic consoles, requires to mark sections which
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modify the UART registers as unsafe. This allows the atomic write function
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to make informed decisions and eventually to restore operational state. It
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also allows to prevent the regular UART code from modifying UART registers
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while printk output is in progress.
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All modifications of UART registers are guarded by the UART port lock,
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which provides an obvious synchronization point with the console
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infrastructure.
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To avoid adding this functionality to all UART drivers, wrap the
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spin_[un]lock*() invocations for uart_port::lock into helper functions
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which just contain the spin_[un]lock*() invocations for now. In a
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subsequent step these helpers will gain the console synchronization
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mechanisms.
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Converted with coccinelle. No functional change.
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Signed-off-by: John Ogness <john.ogness@linutronix.de>
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Link: https://lore.kernel.org/r/20230914183831.587273-34-john.ogness@linutronix.de
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Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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drivers/tty/serial/lpc32xx_hs.c | 26 +++++++++++++-------------
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1 file changed, 13 insertions(+), 13 deletions(-)
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diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
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index b38fe4728c26..5149a947b7fe 100644
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--- a/drivers/tty/serial/lpc32xx_hs.c
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+++ b/drivers/tty/serial/lpc32xx_hs.c
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@@ -140,15 +140,15 @@ static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
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if (up->port.sysrq)
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locked = 0;
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else if (oops_in_progress)
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- locked = spin_trylock(&up->port.lock);
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+ locked = uart_port_trylock(&up->port);
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else
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- spin_lock(&up->port.lock);
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+ uart_port_lock(&up->port);
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uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
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wait_for_xmit_empty(&up->port);
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if (locked)
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- spin_unlock(&up->port.lock);
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+ uart_port_unlock(&up->port);
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local_irq_restore(flags);
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}
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@@ -298,7 +298,7 @@ static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
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struct tty_port *tport = &port->state->port;
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u32 status;
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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/* Read UART status and clear latched interrupts */
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status = readl(LPC32XX_HSUART_IIR(port->membase));
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@@ -333,7 +333,7 @@ static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
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__serial_lpc32xx_tx(port);
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}
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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return IRQ_HANDLED;
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}
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@@ -404,14 +404,14 @@ static void serial_lpc32xx_break_ctl(struct uart_port *port,
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unsigned long flags;
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u32 tmp;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
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if (break_state != 0)
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tmp |= LPC32XX_HSU_BREAK;
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else
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tmp &= ~LPC32XX_HSU_BREAK;
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writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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}
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/* port->lock is not held. */
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@@ -421,7 +421,7 @@ static int serial_lpc32xx_startup(struct uart_port *port)
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unsigned long flags;
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u32 tmp;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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__serial_uart_flush(port);
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@@ -441,7 +441,7 @@ static int serial_lpc32xx_startup(struct uart_port *port)
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lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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retval = request_irq(port->irq, serial_lpc32xx_interrupt,
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0, MODNAME, port);
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@@ -458,7 +458,7 @@ static void serial_lpc32xx_shutdown(struct uart_port *port)
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u32 tmp;
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unsigned long flags;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
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LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
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@@ -466,7 +466,7 @@ static void serial_lpc32xx_shutdown(struct uart_port *port)
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lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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free_irq(port->irq, port);
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}
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@@ -491,7 +491,7 @@ static void serial_lpc32xx_set_termios(struct uart_port *port,
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quot = __serial_get_clock_div(port->uartclk, baud);
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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/* Ignore characters? */
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tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
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@@ -505,7 +505,7 @@ static void serial_lpc32xx_set_termios(struct uart_port *port,
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uart_update_timeout(port, termios->c_cflag, baud);
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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/* Don't rewrite B0 */
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if (tty_termios_baud_rate(termios))
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--
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2.43.2
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