183 lines
6.1 KiB
Diff
183 lines
6.1 KiB
Diff
From c1952a62d5c169b632e1a01092ad0360cc16335a 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 20:44:07 +0206
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Subject: [PATCH 076/198] serial: rda: 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/20230914183831.587273-51-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/rda-uart.c | 34 +++++++++++++++++-----------------
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1 file changed, 17 insertions(+), 17 deletions(-)
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diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c
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index be5c842b5ba9..d824c8318f33 100644
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--- a/drivers/tty/serial/rda-uart.c
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+++ b/drivers/tty/serial/rda-uart.c
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@@ -139,12 +139,12 @@ static unsigned int rda_uart_tx_empty(struct uart_port *port)
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unsigned int ret;
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u32 val;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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val = rda_uart_read(port, RDA_UART_STATUS);
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ret = (val & RDA_UART_TX_FIFO_MASK) ? TIOCSER_TEMT : 0;
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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return ret;
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}
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@@ -246,7 +246,7 @@ static void rda_uart_set_termios(struct uart_port *port,
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unsigned int baud;
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u32 irq_mask;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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baud = uart_get_baud_rate(port, termios, old, 9600, port->uartclk / 4);
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rda_uart_change_baudrate(rda_port, baud);
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@@ -325,7 +325,7 @@ static void rda_uart_set_termios(struct uart_port *port,
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/* update the per-port timeout */
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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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}
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static void rda_uart_send_chars(struct uart_port *port)
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@@ -408,7 +408,7 @@ static irqreturn_t rda_interrupt(int irq, void *dev_id)
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unsigned long flags;
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u32 val, irq_mask;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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/* Clear IRQ cause */
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val = rda_uart_read(port, RDA_UART_IRQ_CAUSE);
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@@ -425,7 +425,7 @@ static irqreturn_t rda_interrupt(int irq, void *dev_id)
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rda_uart_send_chars(port);
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}
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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return IRQ_HANDLED;
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}
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@@ -436,16 +436,16 @@ static int rda_uart_startup(struct uart_port *port)
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int ret;
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u32 val;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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rda_uart_write(port, 0, RDA_UART_IRQ_MASK);
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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ret = request_irq(port->irq, rda_interrupt, IRQF_NO_SUSPEND,
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"rda-uart", port);
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if (ret)
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return ret;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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val = rda_uart_read(port, RDA_UART_CTRL);
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val |= RDA_UART_ENABLE;
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@@ -456,7 +456,7 @@ static int rda_uart_startup(struct uart_port *port)
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val |= (RDA_UART_RX_DATA_AVAILABLE | RDA_UART_RX_TIMEOUT);
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rda_uart_write(port, val, RDA_UART_IRQ_MASK);
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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return 0;
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}
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@@ -466,7 +466,7 @@ static void rda_uart_shutdown(struct uart_port *port)
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unsigned long flags;
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u32 val;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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rda_uart_stop_tx(port);
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rda_uart_stop_rx(port);
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@@ -475,7 +475,7 @@ static void rda_uart_shutdown(struct uart_port *port)
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val &= ~RDA_UART_ENABLE;
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rda_uart_write(port, val, RDA_UART_CTRL);
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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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static const char *rda_uart_type(struct uart_port *port)
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@@ -515,7 +515,7 @@ static void rda_uart_config_port(struct uart_port *port, int flags)
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rda_uart_request_port(port);
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}
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- spin_lock_irqsave(&port->lock, irq_flags);
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+ uart_port_lock_irqsave(port, &irq_flags);
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/* Clear mask, so no surprise interrupts. */
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rda_uart_write(port, 0, RDA_UART_IRQ_MASK);
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@@ -523,7 +523,7 @@ static void rda_uart_config_port(struct uart_port *port, int flags)
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/* Clear status register */
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rda_uart_write(port, 0, RDA_UART_STATUS);
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- spin_unlock_irqrestore(&port->lock, irq_flags);
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+ uart_port_unlock_irqrestore(port, irq_flags);
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}
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static void rda_uart_release_port(struct uart_port *port)
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@@ -597,9 +597,9 @@ static void rda_uart_port_write(struct uart_port *port, const char *s,
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if (port->sysrq) {
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locked = 0;
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} else if (oops_in_progress) {
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- locked = spin_trylock(&port->lock);
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+ locked = uart_port_trylock(port);
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} else {
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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locked = 1;
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}
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@@ -615,7 +615,7 @@ static void rda_uart_port_write(struct uart_port *port, const char *s,
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rda_uart_write(port, old_irq_mask, RDA_UART_IRQ_MASK);
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if (locked)
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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local_irq_restore(flags);
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}
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--
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2.44.0
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