Adding debian version 5.10.209-2.debian/5.10.209-2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 500 insertions, 0 deletions

diff --git a/debian/patches-rt/0100-serial-8250-implement-write_atomic.patch b/debian/patches-rt/0100-serial-8250-implement-write_atomic.patch
new file mode 100644
index 000000000..ad692ff78
--- /dev/null
+++ b/debian/patches-rt/0100-serial-8250-implement-write_atomic.patch
@@ -0,0 +1,500 @@
+From 713182575337acb0891fcfaef75c3a36408d1766 Mon Sep 17 00:00:00 2001
+From: John Ogness <john.ogness@linutronix.de>
+Date: Mon, 30 Nov 2020 01:42:02 +0106
+Subject: [PATCH 100/323] serial: 8250: implement write_atomic
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.204-rt100.tar.xz
+
+Implement a non-sleeping NMI-safe write_atomic() console function in
+order to support emergency console printing.
+
+Since interrupts need to be disabled during transmit, all usage of
+the IER register is wrapped with access functions that use the
+console_atomic_lock() function to synchronize register access while
+tracking the state of the interrupts. This is necessary because
+write_atomic() can be called from an NMI context that has preempted
+write_atomic().
+
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ drivers/tty/serial/8250/8250.h         | 47 ++++++++++++-
+ drivers/tty/serial/8250/8250_core.c    | 17 +++--
+ drivers/tty/serial/8250/8250_fsl.c     |  9 +++
+ drivers/tty/serial/8250/8250_ingenic.c |  7 ++
+ drivers/tty/serial/8250/8250_mtk.c     | 29 +++++++-
+ drivers/tty/serial/8250/8250_port.c    | 92 ++++++++++++++++----------
+ include/linux/serial_8250.h            |  5 ++
+ 7 files changed, 162 insertions(+), 44 deletions(-)
+
+diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
+index 61b11490ae5b..32c534b87397 100644
+--- a/drivers/tty/serial/8250/8250.h
++++ b/drivers/tty/serial/8250/8250.h
+@@ -152,12 +152,55 @@ static inline void serial_dl_write(struct uart_8250_port *up, int value)
+ 	up->dl_write(up, value);
+ }
+ 
++static inline void serial8250_set_IER(struct uart_8250_port *up,
++				      unsigned char ier)
++{
++	struct uart_port *port = &up->port;
++	unsigned int flags;
++	bool is_console;
++
++	is_console = uart_console(port);
++
++	if (is_console)
++		console_atomic_lock(&flags);
++
++	serial_out(up, UART_IER, ier);
++
++	if (is_console)
++		console_atomic_unlock(flags);
++}
++
++static inline unsigned char serial8250_clear_IER(struct uart_8250_port *up)
++{
++	struct uart_port *port = &up->port;
++	unsigned int clearval = 0;
++	unsigned int prior;
++	unsigned int flags;
++	bool is_console;
++
++	is_console = uart_console(port);
++
++	if (up->capabilities & UART_CAP_UUE)
++		clearval = UART_IER_UUE;
++
++	if (is_console)
++		console_atomic_lock(&flags);
++
++	prior = serial_port_in(port, UART_IER);
++	serial_port_out(port, UART_IER, clearval);
++
++	if (is_console)
++		console_atomic_unlock(flags);
++
++	return prior;
++}
++
+ static inline bool serial8250_set_THRI(struct uart_8250_port *up)
+ {
+ 	if (up->ier & UART_IER_THRI)
+ 		return false;
+ 	up->ier |= UART_IER_THRI;
+-	serial_out(up, UART_IER, up->ier);
++	serial8250_set_IER(up, up->ier);
+ 	return true;
+ }
+ 
+@@ -166,7 +209,7 @@ static inline bool serial8250_clear_THRI(struct uart_8250_port *up)
+ 	if (!(up->ier & UART_IER_THRI))
+ 		return false;
+ 	up->ier &= ~UART_IER_THRI;
+-	serial_out(up, UART_IER, up->ier);
++	serial8250_set_IER(up, up->ier);
+ 	return true;
+ }
+ 
+diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
+index 43f2eed6df78..687119fe2f8c 100644
+--- a/drivers/tty/serial/8250/8250_core.c
++++ b/drivers/tty/serial/8250/8250_core.c
+@@ -275,10 +275,8 @@ static void serial8250_backup_timeout(struct timer_list *t)
+ 	 * Must disable interrupts or else we risk racing with the interrupt
+ 	 * based handler.
+ 	 */
+-	if (up->port.irq) {
+-		ier = serial_in(up, UART_IER);
+-		serial_out(up, UART_IER, 0);
+-	}
++	if (up->port.irq)
++		ier = serial8250_clear_IER(up);
+ 
+ 	iir = serial_in(up, UART_IIR);
+ 
+@@ -301,7 +299,7 @@ static void serial8250_backup_timeout(struct timer_list *t)
+ 		serial8250_tx_chars(up);
+ 
+ 	if (up->port.irq)
+-		serial_out(up, UART_IER, ier);
++		serial8250_set_IER(up, ier);
+ 
+ 	spin_unlock_irqrestore(&up->port.lock, flags);
+ 
+@@ -588,6 +586,14 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
+ 
+ #ifdef CONFIG_SERIAL_8250_CONSOLE
+ 
++static void univ8250_console_write_atomic(struct console *co, const char *s,
++					  unsigned int count)
++{
++	struct uart_8250_port *up = &serial8250_ports[co->index];
++
++	serial8250_console_write_atomic(up, s, count);
++}
++
+ static void univ8250_console_write(struct console *co, const char *s,
+ 				   unsigned int count)
+ {
+@@ -681,6 +687,7 @@ static int univ8250_console_match(struct console *co, char *name, int idx,
+ 
+ static struct console univ8250_console = {
+ 	.name		= "ttyS",
++	.write_atomic	= univ8250_console_write_atomic,
+ 	.write		= univ8250_console_write,
+ 	.device		= uart_console_device,
+ 	.setup		= univ8250_console_setup,
+diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
+index fbcc90c31ca1..b33cb454ce03 100644
+--- a/drivers/tty/serial/8250/8250_fsl.c
++++ b/drivers/tty/serial/8250/8250_fsl.c
+@@ -60,9 +60,18 @@ int fsl8250_handle_irq(struct uart_port *port)
+ 
+ 	/* Stop processing interrupts on input overrun */
+ 	if ((orig_lsr & UART_LSR_OE) && (up->overrun_backoff_time_ms > 0)) {
++		unsigned int ca_flags;
+ 		unsigned long delay;
++		bool is_console;
+ 
++		is_console = uart_console(port);
++
++		if (is_console)
++			console_atomic_lock(&ca_flags);
+ 		up->ier = port->serial_in(port, UART_IER);
++		if (is_console)
++			console_atomic_unlock(ca_flags);
++
+ 		if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
+ 			port->ops->stop_rx(port);
+ 		} else {
+diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
+index 988bf6bcce42..bcd26d672539 100644
+--- a/drivers/tty/serial/8250/8250_ingenic.c
++++ b/drivers/tty/serial/8250/8250_ingenic.c
+@@ -146,6 +146,8 @@ OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
+ 
+ static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
+ {
++	unsigned int flags;
++	bool is_console;
+ 	int ier;
+ 
+ 	switch (offset) {
+@@ -167,7 +169,12 @@ static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
+ 		 * If we have enabled modem status IRQs we should enable
+ 		 * modem mode.
+ 		 */
++		is_console = uart_console(p);
++		if (is_console)
++			console_atomic_lock(&flags);
+ 		ier = p->serial_in(p, UART_IER);
++		if (is_console)
++			console_atomic_unlock(flags);
+ 
+ 		if (ier & UART_IER_MSI)
+ 			value |= UART_MCR_MDCE | UART_MCR_FCM;
+diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
+index de48a58460f4..d246f2755fed 100644
+--- a/drivers/tty/serial/8250/8250_mtk.c
++++ b/drivers/tty/serial/8250/8250_mtk.c
+@@ -222,12 +222,37 @@ static void mtk8250_shutdown(struct uart_port *port)
+ 
+ static void mtk8250_disable_intrs(struct uart_8250_port *up, int mask)
+ {
+-	serial_out(up, UART_IER, serial_in(up, UART_IER) & (~mask));
++	struct uart_port *port = &up->port;
++	unsigned int flags;
++	unsigned int ier;
++	bool is_console;
++
++	is_console = uart_console(port);
++
++	if (is_console)
++		console_atomic_lock(&flags);
++
++	ier = serial_in(up, UART_IER);
++	serial_out(up, UART_IER, ier & (~mask));
++
++	if (is_console)
++		console_atomic_unlock(flags);
+ }
+ 
+ static void mtk8250_enable_intrs(struct uart_8250_port *up, int mask)
+ {
+-	serial_out(up, UART_IER, serial_in(up, UART_IER) | mask);
++	struct uart_port *port = &up->port;
++	unsigned int flags;
++	unsigned int ier;
++
++	if (uart_console(port))
++		console_atomic_lock(&flags);
++
++	ier = serial_in(up, UART_IER);
++	serial_out(up, UART_IER, ier | mask);
++
++	if (uart_console(port))
++		console_atomic_unlock(flags);
+ }
+ 
+ static void mtk8250_set_flow_ctrl(struct uart_8250_port *up, int mode)
+diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
+index 8b49ac4856d2..947737d0e46b 100644
+--- a/drivers/tty/serial/8250/8250_port.c
++++ b/drivers/tty/serial/8250/8250_port.c
+@@ -730,7 +730,7 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
+ 			serial_out(p, UART_EFR, UART_EFR_ECB);
+ 			serial_out(p, UART_LCR, 0);
+ 		}
+-		serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
++		serial8250_set_IER(p, sleep ? UART_IERX_SLEEP : 0);
+ 		if (p->capabilities & UART_CAP_EFR) {
+ 			serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
+ 			serial_out(p, UART_EFR, efr);
+@@ -1405,7 +1405,7 @@ static void serial8250_stop_rx(struct uart_port *port)
+ 
+ 	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
+ 	up->port.read_status_mask &= ~UART_LSR_DR;
+-	serial_port_out(port, UART_IER, up->ier);
++	serial8250_set_IER(up, up->ier);
+ 
+ 	serial8250_rpm_put(up);
+ }
+@@ -1435,7 +1435,7 @@ void serial8250_em485_stop_tx(struct uart_8250_port *p)
+ 		serial8250_clear_and_reinit_fifos(p);
+ 
+ 		p->ier |= UART_IER_RLSI | UART_IER_RDI;
+-		serial_port_out(&p->port, UART_IER, p->ier);
++		serial8250_set_IER(p, p->ier);
+ 	}
+ }
+ EXPORT_SYMBOL_GPL(serial8250_em485_stop_tx);
+@@ -1677,7 +1677,7 @@ static void serial8250_disable_ms(struct uart_port *port)
+ 	mctrl_gpio_disable_ms(up->gpios);
+ 
+ 	up->ier &= ~UART_IER_MSI;
+-	serial_port_out(port, UART_IER, up->ier);
++	serial8250_set_IER(up, up->ier);
+ }
+ 
+ static void serial8250_enable_ms(struct uart_port *port)
+@@ -1693,7 +1693,7 @@ static void serial8250_enable_ms(struct uart_port *port)
+ 	up->ier |= UART_IER_MSI;
+ 
+ 	serial8250_rpm_get(up);
+-	serial_port_out(port, UART_IER, up->ier);
++	serial8250_set_IER(up, up->ier);
+ 	serial8250_rpm_put(up);
+ }
+ 
+@@ -2129,14 +2129,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
+ 	struct uart_8250_port *up = up_to_u8250p(port);
+ 
+ 	serial8250_rpm_get(up);
+-	/*
+-	 *	First save the IER then disable the interrupts
+-	 */
+-	ier = serial_port_in(port, UART_IER);
+-	if (up->capabilities & UART_CAP_UUE)
+-		serial_port_out(port, UART_IER, UART_IER_UUE);
+-	else
+-		serial_port_out(port, UART_IER, 0);
++	ier = serial8250_clear_IER(up);
+ 
+ 	wait_for_xmitr(up, BOTH_EMPTY);
+ 	/*
+@@ -2149,7 +2142,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
+ 	 *	and restore the IER
+ 	 */
+ 	wait_for_xmitr(up, BOTH_EMPTY);
+-	serial_port_out(port, UART_IER, ier);
++	serial8250_set_IER(up, ier);
+ 	serial8250_rpm_put(up);
+ }
+ 
+@@ -2454,7 +2447,7 @@ void serial8250_do_shutdown(struct uart_port *port)
+ 	 */
+ 	spin_lock_irqsave(&port->lock, flags);
+ 	up->ier = 0;
+-	serial_port_out(port, UART_IER, 0);
++	serial8250_set_IER(up, 0);
+ 	spin_unlock_irqrestore(&port->lock, flags);
+ 
+ 	synchronize_irq(port->irq);
+@@ -2806,7 +2799,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
+ 	if (up->capabilities & UART_CAP_RTOIE)
+ 		up->ier |= UART_IER_RTOIE;
+ 
+-	serial_port_out(port, UART_IER, up->ier);
++	serial8250_set_IER(up, up->ier);
+ 
+ 	if (up->capabilities & UART_CAP_EFR) {
+ 		unsigned char efr = 0;
+@@ -3271,7 +3264,7 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
+ 
+ #ifdef CONFIG_SERIAL_8250_CONSOLE
+ 
+-static void serial8250_console_putchar(struct uart_port *port, int ch)
++static void serial8250_console_putchar_locked(struct uart_port *port, int ch)
+ {
+ 	struct uart_8250_port *up = up_to_u8250p(port);
+ 
+@@ -3279,6 +3272,18 @@ static void serial8250_console_putchar(struct uart_port *port, int ch)
+ 	serial_port_out(port, UART_TX, ch);
+ }
+ 
++static void serial8250_console_putchar(struct uart_port *port, int ch)
++{
++	struct uart_8250_port *up = up_to_u8250p(port);
++	unsigned int flags;
++
++	wait_for_xmitr(up, UART_LSR_THRE);
++
++	console_atomic_lock(&flags);
++	serial8250_console_putchar_locked(port, ch);
++	console_atomic_unlock(flags);
++}
++
+ /*
+  *	Restore serial console when h/w power-off detected
+  */
+@@ -3305,6 +3310,32 @@ static void serial8250_console_restore(struct uart_8250_port *up)
+ 	serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);
+ }
+ 
++void serial8250_console_write_atomic(struct uart_8250_port *up,
++				     const char *s, unsigned int count)
++{
++	struct uart_port *port = &up->port;
++	unsigned int flags;
++	unsigned int ier;
++
++	console_atomic_lock(&flags);
++
++	touch_nmi_watchdog();
++
++	ier = serial8250_clear_IER(up);
++
++	if (atomic_fetch_inc(&up->console_printing)) {
++		uart_console_write(port, "\n", 1,
++				   serial8250_console_putchar_locked);
++	}
++	uart_console_write(port, s, count, serial8250_console_putchar_locked);
++	atomic_dec(&up->console_printing);
++
++	wait_for_xmitr(up, BOTH_EMPTY);
++	serial8250_set_IER(up, ier);
++
++	console_atomic_unlock(flags);
++}
++
+ /*
+  *	Print a string to the serial port trying not to disturb
+  *	any possible real use of the port...
+@@ -3321,24 +3352,12 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ 	struct uart_port *port = &up->port;
+ 	unsigned long flags;
+ 	unsigned int ier;
+-	int locked = 1;
+ 
+ 	touch_nmi_watchdog();
+ 
+-	if (oops_in_progress)
+-		locked = spin_trylock_irqsave(&port->lock, flags);
+-	else
+-		spin_lock_irqsave(&port->lock, flags);
+-
+-	/*
+-	 *	First save the IER then disable the interrupts
+-	 */
+-	ier = serial_port_in(port, UART_IER);
++	spin_lock_irqsave(&port->lock, flags);
+ 
+-	if (up->capabilities & UART_CAP_UUE)
+-		serial_port_out(port, UART_IER, UART_IER_UUE);
+-	else
+-		serial_port_out(port, UART_IER, 0);
++	ier = serial8250_clear_IER(up);
+ 
+ 	/* check scratch reg to see if port powered off during system sleep */
+ 	if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
+@@ -3352,7 +3371,9 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ 		mdelay(port->rs485.delay_rts_before_send);
+ 	}
+ 
++	atomic_inc(&up->console_printing);
+ 	uart_console_write(port, s, count, serial8250_console_putchar);
++	atomic_dec(&up->console_printing);
+ 
+ 	/*
+ 	 *	Finally, wait for transmitter to become empty
+@@ -3365,8 +3386,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ 		if (em485->tx_stopped)
+ 			up->rs485_stop_tx(up);
+ 	}
+-
+-	serial_port_out(port, UART_IER, ier);
++	serial8250_set_IER(up, ier);
+ 
+ 	/*
+ 	 *	The receive handling will happen properly because the
+@@ -3378,8 +3398,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ 	if (up->msr_saved_flags)
+ 		serial8250_modem_status(up);
+ 
+-	if (locked)
+-		spin_unlock_irqrestore(&port->lock, flags);
++	spin_unlock_irqrestore(&port->lock, flags);
+ }
+ 
+ static unsigned int probe_baud(struct uart_port *port)
+@@ -3399,6 +3418,7 @@ static unsigned int probe_baud(struct uart_port *port)
+ 
+ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
+ {
++	struct uart_8250_port *up = up_to_u8250p(port);
+ 	int baud = 9600;
+ 	int bits = 8;
+ 	int parity = 'n';
+@@ -3408,6 +3428,8 @@ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
+ 	if (!port->iobase && !port->membase)
+ 		return -ENODEV;
+ 
++	atomic_set(&up->console_printing, 0);
++
+ 	if (options)
+ 		uart_parse_options(options, &baud, &parity, &bits, &flow);
+ 	else if (probe)
+diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
+index abb928361270..77de68ed2d60 100644
+--- a/include/linux/serial_8250.h
++++ b/include/linux/serial_8250.h
+@@ -7,6 +7,7 @@
+ #ifndef _LINUX_SERIAL_8250_H
+ #define _LINUX_SERIAL_8250_H
+ 
++#include <linux/atomic.h>
+ #include <linux/serial_core.h>
+ #include <linux/serial_reg.h>
+ #include <linux/platform_device.h>
+@@ -125,6 +126,8 @@ struct uart_8250_port {
+ #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
+ 	unsigned char		msr_saved_flags;
+ 
++	atomic_t		console_printing;
++
+ 	struct uart_8250_dma	*dma;
+ 	const struct uart_8250_ops *ops;
+ 
+@@ -180,6 +183,8 @@ void serial8250_init_port(struct uart_8250_port *up);
+ void serial8250_set_defaults(struct uart_8250_port *up);
+ void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ 			      unsigned int count);
++void serial8250_console_write_atomic(struct uart_8250_port *up, const char *s,
++				     unsigned int count);
+ int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
+ int serial8250_console_exit(struct uart_port *port);
+ 
+-- 
+2.43.0
+