1 files changed, 354 insertions, 0 deletions

diff --git a/debian/patches-rt/0029-serial-imx-Use-port-lock-wrappers.patch b/debian/patches-rt/0029-serial-imx-Use-port-lock-wrappers.patch
new file mode 100644
index 000000000..24f582ae8
--- /dev/null
+++ b/debian/patches-rt/0029-serial-imx-Use-port-lock-wrappers.patch
@@ -0,0 +1,354 @@
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:43:46 +0206
+Subject: [PATCH 029/134] serial: imx: Use port lock wrappers
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6.7-rt18.tar.xz
+
+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/20230914183831.587273-30-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/imx.c |   84 +++++++++++++++++++++++------------------------
+ 1 file changed, 42 insertions(+), 42 deletions(-)
+
+--- a/drivers/tty/serial/imx.c
++++ b/drivers/tty/serial/imx.c
+@@ -575,7 +575,7 @@ static void imx_uart_dma_tx_callback(voi
+ 	unsigned long flags;
+ 	u32 ucr1;
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
+ 
+@@ -600,7 +600,7 @@ static void imx_uart_dma_tx_callback(voi
+ 		imx_uart_writel(sport, ucr4, UCR4);
+ 	}
+ 
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ }
+ 
+ /* called with port.lock taken and irqs off */
+@@ -766,11 +766,11 @@ static irqreturn_t imx_uart_rtsint(int i
+ 	struct imx_port *sport = dev_id;
+ 	irqreturn_t ret;
+ 
+-	spin_lock(&sport->port.lock);
++	uart_port_lock(&sport->port);
+ 
+ 	ret = __imx_uart_rtsint(irq, dev_id);
+ 
+-	spin_unlock(&sport->port.lock);
++	uart_port_unlock(&sport->port);
+ 
+ 	return ret;
+ }
+@@ -779,9 +779,9 @@ static irqreturn_t imx_uart_txint(int ir
+ {
+ 	struct imx_port *sport = dev_id;
+ 
+-	spin_lock(&sport->port.lock);
++	uart_port_lock(&sport->port);
+ 	imx_uart_transmit_buffer(sport);
+-	spin_unlock(&sport->port.lock);
++	uart_port_unlock(&sport->port);
+ 	return IRQ_HANDLED;
+ }
+ 
+@@ -895,11 +895,11 @@ static irqreturn_t imx_uart_rxint(int ir
+ 	struct imx_port *sport = dev_id;
+ 	irqreturn_t ret;
+ 
+-	spin_lock(&sport->port.lock);
++	uart_port_lock(&sport->port);
+ 
+ 	ret = __imx_uart_rxint(irq, dev_id);
+ 
+-	spin_unlock(&sport->port.lock);
++	uart_port_unlock(&sport->port);
+ 
+ 	return ret;
+ }
+@@ -962,7 +962,7 @@ static irqreturn_t imx_uart_int(int irq,
+ 	unsigned int usr1, usr2, ucr1, ucr2, ucr3, ucr4;
+ 	irqreturn_t ret = IRQ_NONE;
+ 
+-	spin_lock(&sport->port.lock);
++	uart_port_lock(&sport->port);
+ 
+ 	usr1 = imx_uart_readl(sport, USR1);
+ 	usr2 = imx_uart_readl(sport, USR2);
+@@ -1032,7 +1032,7 @@ static irqreturn_t imx_uart_int(int irq,
+ 		ret = IRQ_HANDLED;
+ 	}
+ 
+-	spin_unlock(&sport->port.lock);
++	uart_port_unlock(&sport->port);
+ 
+ 	return ret;
+ }
+@@ -1115,7 +1115,7 @@ static void imx_uart_break_ctl(struct ua
+ 	unsigned long flags;
+ 	u32 ucr1;
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	ucr1 = imx_uart_readl(sport, UCR1) & ~UCR1_SNDBRK;
+ 
+@@ -1124,7 +1124,7 @@ static void imx_uart_break_ctl(struct ua
+ 
+ 	imx_uart_writel(sport, ucr1, UCR1);
+ 
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ }
+ 
+ /*
+@@ -1137,9 +1137,9 @@ static void imx_uart_timeout(struct time
+ 	unsigned long flags;
+ 
+ 	if (sport->port.state) {
+-		spin_lock_irqsave(&sport->port.lock, flags);
++		uart_port_lock_irqsave(&sport->port, &flags);
+ 		imx_uart_mctrl_check(sport);
+-		spin_unlock_irqrestore(&sport->port.lock, flags);
++		uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 		mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
+ 	}
+@@ -1169,9 +1169,9 @@ static void imx_uart_dma_rx_callback(voi
+ 	status = dmaengine_tx_status(chan, sport->rx_cookie, &state);
+ 
+ 	if (status == DMA_ERROR) {
+-		spin_lock(&sport->port.lock);
++		uart_port_lock(&sport->port);
+ 		imx_uart_clear_rx_errors(sport);
+-		spin_unlock(&sport->port.lock);
++		uart_port_unlock(&sport->port);
+ 		return;
+ 	}
+ 
+@@ -1200,9 +1200,9 @@ static void imx_uart_dma_rx_callback(voi
+ 		r_bytes = rx_ring->head - rx_ring->tail;
+ 
+ 		/* If we received something, check for 0xff flood */
+-		spin_lock(&sport->port.lock);
++		uart_port_lock(&sport->port);
+ 		imx_uart_check_flood(sport, imx_uart_readl(sport, USR2));
+-		spin_unlock(&sport->port.lock);
++		uart_port_unlock(&sport->port);
+ 
+ 		if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ)) {
+ 
+@@ -1460,7 +1460,7 @@ static int imx_uart_startup(struct uart_
+ 	if (!uart_console(port) && imx_uart_dma_init(sport) == 0)
+ 		dma_is_inited = 1;
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	/* Reset fifo's and state machines */
+ 	imx_uart_soft_reset(sport);
+@@ -1533,7 +1533,7 @@ static int imx_uart_startup(struct uart_
+ 
+ 	imx_uart_disable_loopback_rs485(sport);
+ 
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 	return 0;
+ }
+@@ -1558,21 +1558,21 @@ static void imx_uart_shutdown(struct uar
+ 			sport->dma_is_rxing = 0;
+ 		}
+ 
+-		spin_lock_irqsave(&sport->port.lock, flags);
++		uart_port_lock_irqsave(&sport->port, &flags);
+ 		imx_uart_stop_tx(port);
+ 		imx_uart_stop_rx(port);
+ 		imx_uart_disable_dma(sport);
+-		spin_unlock_irqrestore(&sport->port.lock, flags);
++		uart_port_unlock_irqrestore(&sport->port, flags);
+ 		imx_uart_dma_exit(sport);
+ 	}
+ 
+ 	mctrl_gpio_disable_ms(sport->gpios);
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 	ucr2 = imx_uart_readl(sport, UCR2);
+ 	ucr2 &= ~(UCR2_TXEN | UCR2_ATEN);
+ 	imx_uart_writel(sport, ucr2, UCR2);
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 	/*
+ 	 * Stop our timer.
+@@ -1583,7 +1583,7 @@ static void imx_uart_shutdown(struct uar
+ 	 * Disable all interrupts, port and break condition.
+ 	 */
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	ucr1 = imx_uart_readl(sport, UCR1);
+ 	ucr1 &= ~(UCR1_TRDYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_RXDMAEN |
+@@ -1605,7 +1605,7 @@ static void imx_uart_shutdown(struct uar
+ 	ucr4 &= ~UCR4_TCEN;
+ 	imx_uart_writel(sport, ucr4, UCR4);
+ 
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 	clk_disable_unprepare(sport->clk_per);
+ 	clk_disable_unprepare(sport->clk_ipg);
+@@ -1668,7 +1668,7 @@ imx_uart_set_termios(struct uart_port *p
+ 	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
+ 	quot = uart_get_divisor(port, baud);
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	/*
+ 	 * Read current UCR2 and save it for future use, then clear all the bits
+@@ -1796,7 +1796,7 @@ imx_uart_set_termios(struct uart_port *p
+ 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
+ 		imx_uart_enable_ms(&sport->port);
+ 
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ }
+ 
+ static const char *imx_uart_type(struct uart_port *port)
+@@ -1858,7 +1858,7 @@ static int imx_uart_poll_init(struct uar
+ 
+ 	imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	/*
+ 	 * Be careful about the order of enabling bits here. First enable the
+@@ -1886,7 +1886,7 @@ static int imx_uart_poll_init(struct uar
+ 	imx_uart_writel(sport, ucr1 | UCR1_RRDYEN, UCR1);
+ 	imx_uart_writel(sport, ucr2 | UCR2_ATEN, UCR2);
+ 
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 	return 0;
+ }
+@@ -2005,9 +2005,9 @@ imx_uart_console_write(struct console *c
+ 	if (sport->port.sysrq)
+ 		locked = 0;
+ 	else if (oops_in_progress)
+-		locked = spin_trylock_irqsave(&sport->port.lock, flags);
++		locked = uart_port_trylock_irqsave(&sport->port, &flags);
+ 	else
+-		spin_lock_irqsave(&sport->port.lock, flags);
++		uart_port_lock_irqsave(&sport->port, &flags);
+ 
+ 	/*
+ 	 *	First, save UCR1/2/3 and then disable interrupts
+@@ -2035,7 +2035,7 @@ imx_uart_console_write(struct console *c
+ 	imx_uart_ucrs_restore(sport, &old_ucr);
+ 
+ 	if (locked)
+-		spin_unlock_irqrestore(&sport->port.lock, flags);
++		uart_port_unlock_irqrestore(&sport->port, flags);
+ }
+ 
+ /*
+@@ -2193,10 +2193,10 @@ static enum hrtimer_restart imx_trigger_
+ 	struct imx_port *sport = container_of(t, struct imx_port, trigger_start_tx);
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 	if (sport->tx_state == WAIT_AFTER_RTS)
+ 		imx_uart_start_tx(&sport->port);
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 	return HRTIMER_NORESTART;
+ }
+@@ -2206,10 +2206,10 @@ static enum hrtimer_restart imx_trigger_
+ 	struct imx_port *sport = container_of(t, struct imx_port, trigger_stop_tx);
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 	if (sport->tx_state == WAIT_AFTER_SEND)
+ 		imx_uart_stop_tx(&sport->port);
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ 
+ 	return HRTIMER_NORESTART;
+ }
+@@ -2482,9 +2482,9 @@ static void imx_uart_restore_context(str
+ {
+ 	unsigned long flags;
+ 
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 	if (!sport->context_saved) {
+-		spin_unlock_irqrestore(&sport->port.lock, flags);
++		uart_port_unlock_irqrestore(&sport->port, flags);
+ 		return;
+ 	}
+ 
+@@ -2499,7 +2499,7 @@ static void imx_uart_restore_context(str
+ 	imx_uart_writel(sport, sport->saved_reg[2], UCR3);
+ 	imx_uart_writel(sport, sport->saved_reg[3], UCR4);
+ 	sport->context_saved = false;
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ }
+ 
+ static void imx_uart_save_context(struct imx_port *sport)
+@@ -2507,7 +2507,7 @@ static void imx_uart_save_context(struct
+ 	unsigned long flags;
+ 
+ 	/* Save necessary regs */
+-	spin_lock_irqsave(&sport->port.lock, flags);
++	uart_port_lock_irqsave(&sport->port, &flags);
+ 	sport->saved_reg[0] = imx_uart_readl(sport, UCR1);
+ 	sport->saved_reg[1] = imx_uart_readl(sport, UCR2);
+ 	sport->saved_reg[2] = imx_uart_readl(sport, UCR3);
+@@ -2519,7 +2519,7 @@ static void imx_uart_save_context(struct
+ 	sport->saved_reg[8] = imx_uart_readl(sport, UBMR);
+ 	sport->saved_reg[9] = imx_uart_readl(sport, IMX21_UTS);
+ 	sport->context_saved = true;
+-	spin_unlock_irqrestore(&sport->port.lock, flags);
++	uart_port_unlock_irqrestore(&sport->port, flags);
+ }
+ 
+ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)