[All] {WIP} The big bump to buildroot 2024.02.x

buildroot-external/patches/linux/0041-serial-altera_uart-Use-port-lock-wrappers.patch

@@ -0,0 +1,121 @@
+From db6d50be344aa102ac938287676ab60e9cb2dc39 Mon Sep 17 00:00:00 2001
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:43:32 +0206
+Subject: [PATCH 041/196] serial: altera_uart: 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/20230914183831.587273-16-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/altera_uart.c | 20 ++++++++++----------
+ 1 file changed, 10 insertions(+), 10 deletions(-)
+
+diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
+index a9c41942190c..77835ac68df2 100644
+--- a/drivers/tty/serial/altera_uart.c
++++ b/drivers/tty/serial/altera_uart.c
+@@ -164,13 +164,13 @@ static void altera_uart_break_ctl(struct uart_port *port, int break_state)
+ 	struct altera_uart *pp = container_of(port, struct altera_uart, port);
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&port->lock, flags);
++	uart_port_lock_irqsave(port, &flags);
+ 	if (break_state == -1)
+ 		pp->imr |= ALTERA_UART_CONTROL_TRBK_MSK;
+ 	else
+ 		pp->imr &= ~ALTERA_UART_CONTROL_TRBK_MSK;
+ 	altera_uart_update_ctrl_reg(pp);
+-	spin_unlock_irqrestore(&port->lock, flags);
++	uart_port_unlock_irqrestore(port, flags);
+ }
+ 
+ static void altera_uart_set_termios(struct uart_port *port,
+@@ -187,10 +187,10 @@ static void altera_uart_set_termios(struct uart_port *port,
+ 		tty_termios_copy_hw(termios, old);
+ 	tty_termios_encode_baud_rate(termios, baud, baud);
+ 
+-	spin_lock_irqsave(&port->lock, flags);
++	uart_port_lock_irqsave(port, &flags);
+ 	uart_update_timeout(port, termios->c_cflag, baud);
+ 	altera_uart_writel(port, baudclk, ALTERA_UART_DIVISOR_REG);
+-	spin_unlock_irqrestore(&port->lock, flags);
++	uart_port_unlock_irqrestore(port, flags);
+ 
+ 	/*
+ 	 * FIXME: port->read_status_mask and port->ignore_status_mask
+@@ -264,12 +264,12 @@ static irqreturn_t altera_uart_interrupt(int irq, void *data)
+ 
+ 	isr = altera_uart_readl(port, ALTERA_UART_STATUS_REG) & pp->imr;
+ 
+-	spin_lock_irqsave(&port->lock, flags);
++	uart_port_lock_irqsave(port, &flags);
+ 	if (isr & ALTERA_UART_STATUS_RRDY_MSK)
+ 		altera_uart_rx_chars(port);
+ 	if (isr & ALTERA_UART_STATUS_TRDY_MSK)
+ 		altera_uart_tx_chars(port);
+-	spin_unlock_irqrestore(&port->lock, flags);
++	uart_port_unlock_irqrestore(port, flags);
+ 
+ 	return IRQ_RETVAL(isr);
+ }
+@@ -313,13 +313,13 @@ static int altera_uart_startup(struct uart_port *port)
+ 		}
+ 	}
+ 
+-	spin_lock_irqsave(&port->lock, flags);
++	uart_port_lock_irqsave(port, &flags);
+ 
+ 	/* Enable RX interrupts now */
+ 	pp->imr = ALTERA_UART_CONTROL_RRDY_MSK;
+ 	altera_uart_update_ctrl_reg(pp);
+ 
+-	spin_unlock_irqrestore(&port->lock, flags);
++	uart_port_unlock_irqrestore(port, flags);
+ 
+ 	return 0;
+ }
+@@ -329,13 +329,13 @@ static void altera_uart_shutdown(struct uart_port *port)
+ 	struct altera_uart *pp = container_of(port, struct altera_uart, port);
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&port->lock, flags);
++	uart_port_lock_irqsave(port, &flags);
+ 
+ 	/* Disable all interrupts now */
+ 	pp->imr = 0;
+ 	altera_uart_update_ctrl_reg(pp);
+ 
+-	spin_unlock_irqrestore(&port->lock, flags);
++	uart_port_unlock_irqrestore(port, flags);
+ 
+ 	if (port->irq)
+ 		free_irq(port->irq, port);
+-- 
+2.43.2
+