150 lines
5.3 KiB
Diff
150 lines
5.3 KiB
Diff
From 8777b7deb3069b2747696a2971979eaf11d0d42c Mon Sep 17 00:00:00 2001
|
|
From: Thomas Gleixner <tglx@linutronix.de>
|
|
Date: Thu, 14 Sep 2023 20:43:36 +0206
|
|
Subject: [PATCH 045/196] serial: ar933x: Use port lock wrappers
|
|
|
|
When a serial port is used for kernel console output, then all
|
|
modifications to the UART registers which are done from other contexts,
|
|
e.g. getty, termios, are interference points for the kernel console.
|
|
|
|
So far this has been ignored and the printk output is based on the
|
|
principle of hope. The rework of the console infrastructure which aims to
|
|
support threaded and atomic consoles, requires to mark sections which
|
|
modify the UART registers as unsafe. This allows the atomic write function
|
|
to make informed decisions and eventually to restore operational state. It
|
|
also allows to prevent the regular UART code from modifying UART registers
|
|
while printk output is in progress.
|
|
|
|
All modifications of UART registers are guarded by the UART port lock,
|
|
which provides an obvious synchronization point with the console
|
|
infrastructure.
|
|
|
|
To avoid adding this functionality to all UART drivers, wrap the
|
|
spin_[un]lock*() invocations for uart_port::lock into helper functions
|
|
which just contain the spin_[un]lock*() invocations for now. In a
|
|
subsequent step these helpers will gain the console synchronization
|
|
mechanisms.
|
|
|
|
Converted with coccinelle. No functional change.
|
|
|
|
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
Signed-off-by: John Ogness <john.ogness@linutronix.de>
|
|
Link: https://lore.kernel.org/r/20230914183831.587273-20-john.ogness@linutronix.de
|
|
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
---
|
|
drivers/tty/serial/ar933x_uart.c | 26 +++++++++++++-------------
|
|
1 file changed, 13 insertions(+), 13 deletions(-)
|
|
|
|
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
|
|
index 924c1a89347c..ffd234673177 100644
|
|
--- a/drivers/tty/serial/ar933x_uart.c
|
|
+++ b/drivers/tty/serial/ar933x_uart.c
|
|
@@ -133,9 +133,9 @@ static unsigned int ar933x_uart_tx_empty(struct uart_port *port)
|
|
unsigned long flags;
|
|
unsigned int rdata;
|
|
|
|
- spin_lock_irqsave(&up->port.lock, flags);
|
|
+ uart_port_lock_irqsave(&up->port, &flags);
|
|
rdata = ar933x_uart_read(up, AR933X_UART_DATA_REG);
|
|
- spin_unlock_irqrestore(&up->port.lock, flags);
|
|
+ uart_port_unlock_irqrestore(&up->port, flags);
|
|
|
|
return (rdata & AR933X_UART_DATA_TX_CSR) ? 0 : TIOCSER_TEMT;
|
|
}
|
|
@@ -220,14 +220,14 @@ static void ar933x_uart_break_ctl(struct uart_port *port, int break_state)
|
|
container_of(port, struct ar933x_uart_port, port);
|
|
unsigned long flags;
|
|
|
|
- spin_lock_irqsave(&up->port.lock, flags);
|
|
+ uart_port_lock_irqsave(&up->port, &flags);
|
|
if (break_state == -1)
|
|
ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
|
|
AR933X_UART_CS_TX_BREAK);
|
|
else
|
|
ar933x_uart_rmw_clear(up, AR933X_UART_CS_REG,
|
|
AR933X_UART_CS_TX_BREAK);
|
|
- spin_unlock_irqrestore(&up->port.lock, flags);
|
|
+ uart_port_unlock_irqrestore(&up->port, flags);
|
|
}
|
|
|
|
/*
|
|
@@ -318,7 +318,7 @@ static void ar933x_uart_set_termios(struct uart_port *port,
|
|
* Ok, we're now changing the port state. Do it with
|
|
* interrupts disabled.
|
|
*/
|
|
- spin_lock_irqsave(&up->port.lock, flags);
|
|
+ uart_port_lock_irqsave(&up->port, &flags);
|
|
|
|
/* disable the UART */
|
|
ar933x_uart_rmw_clear(up, AR933X_UART_CS_REG,
|
|
@@ -352,7 +352,7 @@ static void ar933x_uart_set_termios(struct uart_port *port,
|
|
AR933X_UART_CS_IF_MODE_M << AR933X_UART_CS_IF_MODE_S,
|
|
AR933X_UART_CS_IF_MODE_DCE << AR933X_UART_CS_IF_MODE_S);
|
|
|
|
- spin_unlock_irqrestore(&up->port.lock, flags);
|
|
+ uart_port_unlock_irqrestore(&up->port, flags);
|
|
|
|
if (tty_termios_baud_rate(new))
|
|
tty_termios_encode_baud_rate(new, baud, baud);
|
|
@@ -450,7 +450,7 @@ static irqreturn_t ar933x_uart_interrupt(int irq, void *dev_id)
|
|
if ((status & AR933X_UART_CS_HOST_INT) == 0)
|
|
return IRQ_NONE;
|
|
|
|
- spin_lock(&up->port.lock);
|
|
+ uart_port_lock(&up->port);
|
|
|
|
status = ar933x_uart_read(up, AR933X_UART_INT_REG);
|
|
status &= ar933x_uart_read(up, AR933X_UART_INT_EN_REG);
|
|
@@ -468,7 +468,7 @@ static irqreturn_t ar933x_uart_interrupt(int irq, void *dev_id)
|
|
ar933x_uart_tx_chars(up);
|
|
}
|
|
|
|
- spin_unlock(&up->port.lock);
|
|
+ uart_port_unlock(&up->port);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
@@ -485,7 +485,7 @@ static int ar933x_uart_startup(struct uart_port *port)
|
|
if (ret)
|
|
return ret;
|
|
|
|
- spin_lock_irqsave(&up->port.lock, flags);
|
|
+ uart_port_lock_irqsave(&up->port, &flags);
|
|
|
|
/* Enable HOST interrupts */
|
|
ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
|
|
@@ -498,7 +498,7 @@ static int ar933x_uart_startup(struct uart_port *port)
|
|
/* Enable RX interrupts */
|
|
ar933x_uart_start_rx_interrupt(up);
|
|
|
|
- spin_unlock_irqrestore(&up->port.lock, flags);
|
|
+ uart_port_unlock_irqrestore(&up->port, flags);
|
|
|
|
return 0;
|
|
}
|
|
@@ -632,9 +632,9 @@ static void ar933x_uart_console_write(struct console *co, const char *s,
|
|
if (up->port.sysrq)
|
|
locked = 0;
|
|
else if (oops_in_progress)
|
|
- locked = spin_trylock(&up->port.lock);
|
|
+ locked = uart_port_trylock(&up->port);
|
|
else
|
|
- spin_lock(&up->port.lock);
|
|
+ uart_port_lock(&up->port);
|
|
|
|
/*
|
|
* First save the IER then disable the interrupts
|
|
@@ -654,7 +654,7 @@ static void ar933x_uart_console_write(struct console *co, const char *s,
|
|
ar933x_uart_write(up, AR933X_UART_INT_REG, AR933X_UART_INT_ALLINTS);
|
|
|
|
if (locked)
|
|
- spin_unlock(&up->port.lock);
|
|
+ uart_port_unlock(&up->port);
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
--
|
|
2.43.2
|
|
|