157 lines
5.5 KiB
Diff
157 lines
5.5 KiB
Diff
From 9b3ce8f4924d20af62e1958030c88c035e5664a6 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 20:43:22 +0206
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Subject: [PATCH 032/195] serial: 8250_bcm7271: 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/20230914183831.587273-6-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/8250/8250_bcm7271.c | 28 +++++++++++++-------------
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1 file changed, 14 insertions(+), 14 deletions(-)
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diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c
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index aa5aff046756..ff0662c68725 100644
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--- a/drivers/tty/serial/8250/8250_bcm7271.c
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+++ b/drivers/tty/serial/8250/8250_bcm7271.c
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@@ -567,7 +567,7 @@ static irqreturn_t brcmuart_isr(int irq, void *dev_id)
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if (interrupts == 0)
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return IRQ_NONE;
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- spin_lock_irqsave(&up->lock, flags);
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+ uart_port_lock_irqsave(up, &flags);
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/* Clear all interrupts */
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udma_writel(priv, REGS_DMA_ISR, UDMA_INTR_CLEAR, interrupts);
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@@ -581,7 +581,7 @@ static irqreturn_t brcmuart_isr(int irq, void *dev_id)
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if ((rval | tval) == 0)
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dev_warn(dev, "Spurious interrupt: 0x%x\n", interrupts);
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- spin_unlock_irqrestore(&up->lock, flags);
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+ uart_port_unlock_irqrestore(up, flags);
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return IRQ_HANDLED;
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}
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@@ -608,10 +608,10 @@ static int brcmuart_startup(struct uart_port *port)
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*
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* Synchronize UART_IER access against the console.
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*/
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- spin_lock_irq(&port->lock);
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+ uart_port_lock_irq(port);
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up->ier &= ~UART_IER_RDI;
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serial_port_out(port, UART_IER, up->ier);
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- spin_unlock_irq(&port->lock);
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+ uart_port_unlock_irq(port);
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priv->tx_running = false;
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priv->dma.rx_dma = NULL;
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@@ -629,7 +629,7 @@ static void brcmuart_shutdown(struct uart_port *port)
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struct brcmuart_priv *priv = up->port.private_data;
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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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priv->shutdown = true;
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if (priv->dma_enabled) {
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stop_rx_dma(up);
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@@ -645,7 +645,7 @@ static void brcmuart_shutdown(struct uart_port *port)
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*/
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up->dma = NULL;
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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serial8250_do_shutdown(port);
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}
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@@ -788,7 +788,7 @@ static int brcmuart_handle_irq(struct uart_port *p)
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* interrupt but there is no data ready.
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*/
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if (((iir & UART_IIR_ID) == UART_IIR_RX_TIMEOUT) && !(priv->shutdown)) {
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- spin_lock_irqsave(&p->lock, flags);
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+ uart_port_lock_irqsave(p, &flags);
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status = serial_port_in(p, UART_LSR);
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if ((status & UART_LSR_DR) == 0) {
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@@ -813,7 +813,7 @@ static int brcmuart_handle_irq(struct uart_port *p)
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handled = 1;
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}
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- spin_unlock_irqrestore(&p->lock, flags);
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+ uart_port_unlock_irqrestore(p, flags);
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if (handled)
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return 1;
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}
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@@ -831,7 +831,7 @@ static enum hrtimer_restart brcmuart_hrtimer_func(struct hrtimer *t)
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if (priv->shutdown)
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return HRTIMER_NORESTART;
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- spin_lock_irqsave(&p->lock, flags);
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+ uart_port_lock_irqsave(p, &flags);
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status = serial_port_in(p, UART_LSR);
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/*
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@@ -855,7 +855,7 @@ static enum hrtimer_restart brcmuart_hrtimer_func(struct hrtimer *t)
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status |= UART_MCR_RTS;
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serial_port_out(p, UART_MCR, status);
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}
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- spin_unlock_irqrestore(&p->lock, flags);
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+ uart_port_unlock_irqrestore(p, flags);
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return HRTIMER_NORESTART;
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}
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@@ -1154,10 +1154,10 @@ static int __maybe_unused brcmuart_suspend(struct device *dev)
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* This will prevent resume from enabling RTS before the
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* baud rate has been restored.
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*/
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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priv->saved_mctrl = port->mctrl;
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port->mctrl &= ~TIOCM_RTS;
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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serial8250_suspend_port(priv->line);
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clk_disable_unprepare(priv->baud_mux_clk);
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@@ -1196,10 +1196,10 @@ static int __maybe_unused brcmuart_resume(struct device *dev)
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if (priv->saved_mctrl & TIOCM_RTS) {
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/* Restore RTS */
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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port->mctrl |= TIOCM_RTS;
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port->ops->set_mctrl(port, port->mctrl);
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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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return 0;
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--
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2.43.0
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