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-rw-r--r--debian/patches-rt/0069-serial-sunzilog-Use-port-lock-wrappers.patch211
1 files changed, 211 insertions, 0 deletions
diff --git a/debian/patches-rt/0069-serial-sunzilog-Use-port-lock-wrappers.patch b/debian/patches-rt/0069-serial-sunzilog-Use-port-lock-wrappers.patch
new file mode 100644
index 0000000000..dca4327a46
--- /dev/null
+++ b/debian/patches-rt/0069-serial-sunzilog-Use-port-lock-wrappers.patch
@@ -0,0 +1,211 @@
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:44:26 +0206
+Subject: [PATCH 069/134] serial: sunzilog: 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/20230914183831.587273-70-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/sunzilog.c | 42 +++++++++++++++++++++---------------------
+ 1 file changed, 21 insertions(+), 21 deletions(-)
+
+--- a/drivers/tty/serial/sunzilog.c
++++ b/drivers/tty/serial/sunzilog.c
+@@ -531,7 +531,7 @@ static irqreturn_t sunzilog_interrupt(in
+ struct tty_port *port;
+ unsigned char r3;
+
+- spin_lock(&up->port.lock);
++ uart_port_lock(&up->port);
+ r3 = read_zsreg(channel, R3);
+
+ /* Channel A */
+@@ -548,7 +548,7 @@ static irqreturn_t sunzilog_interrupt(in
+ if (r3 & CHATxIP)
+ sunzilog_transmit_chars(up, channel);
+ }
+- spin_unlock(&up->port.lock);
++ uart_port_unlock(&up->port);
+
+ if (port)
+ tty_flip_buffer_push(port);
+@@ -557,7 +557,7 @@ static irqreturn_t sunzilog_interrupt(in
+ up = up->next;
+ channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
+
+- spin_lock(&up->port.lock);
++ uart_port_lock(&up->port);
+ port = NULL;
+ if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
+ writeb(RES_H_IUS, &channel->control);
+@@ -571,7 +571,7 @@ static irqreturn_t sunzilog_interrupt(in
+ if (r3 & CHBTxIP)
+ sunzilog_transmit_chars(up, channel);
+ }
+- spin_unlock(&up->port.lock);
++ uart_port_unlock(&up->port);
+
+ if (port)
+ tty_flip_buffer_push(port);
+@@ -604,11 +604,11 @@ static unsigned int sunzilog_tx_empty(st
+ unsigned char status;
+ unsigned int ret;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ status = sunzilog_read_channel_status(port);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ if (status & Tx_BUF_EMP)
+ ret = TIOCSER_TEMT;
+@@ -764,7 +764,7 @@ static void sunzilog_break_ctl(struct ua
+ else
+ clear_bits |= SND_BRK;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ new_reg = (up->curregs[R5] | set_bits) & ~clear_bits;
+ if (new_reg != up->curregs[R5]) {
+@@ -774,7 +774,7 @@ static void sunzilog_break_ctl(struct ua
+ write_zsreg(channel, R5, up->curregs[R5]);
+ }
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static void __sunzilog_startup(struct uart_sunzilog_port *up)
+@@ -800,9 +800,9 @@ static int sunzilog_startup(struct uart_
+ if (ZS_IS_CONS(up))
+ return 0;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ __sunzilog_startup(up);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ return 0;
+ }
+
+@@ -840,7 +840,7 @@ static void sunzilog_shutdown(struct uar
+ if (ZS_IS_CONS(up))
+ return;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ channel = ZILOG_CHANNEL_FROM_PORT(port);
+
+@@ -853,7 +853,7 @@ static void sunzilog_shutdown(struct uar
+ up->curregs[R5] &= ~SND_BRK;
+ sunzilog_maybe_update_regs(up, channel);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ /* Shared by TTY driver and serial console setup. The port lock is held
+@@ -945,7 +945,7 @@ sunzilog_set_termios(struct uart_port *p
+
+ baud = uart_get_baud_rate(port, termios, old, 1200, 76800);
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
+
+@@ -962,7 +962,7 @@ sunzilog_set_termios(struct uart_port *p
+
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ }
+
+ static const char *sunzilog_type(struct uart_port *port)
+@@ -1201,15 +1201,15 @@ sunzilog_console_write(struct console *c
+ int locked = 1;
+
+ if (up->port.sysrq || oops_in_progress)
+- locked = spin_trylock_irqsave(&up->port.lock, flags);
++ locked = uart_port_trylock_irqsave(&up->port, &flags);
+ else
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ uart_console_write(&up->port, s, count, sunzilog_putchar);
+ udelay(2);
+
+ if (locked)
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ }
+
+ static int __init sunzilog_console_setup(struct console *con, char *options)
+@@ -1244,7 +1244,7 @@ static int __init sunzilog_console_setup
+
+ brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ up->curregs[R15] |= BRKIE;
+ sunzilog_convert_to_zs(up, con->cflag, 0, brg);
+@@ -1252,7 +1252,7 @@ static int __init sunzilog_console_setup
+ sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
+ __sunzilog_startup(up);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+
+ return 0;
+ }
+@@ -1333,7 +1333,7 @@ static void sunzilog_init_hw(struct uart
+
+ channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+ if (ZS_IS_CHANNEL_A(up)) {
+ write_zsreg(channel, R9, FHWRES);
+ ZSDELAY_LONG();
+@@ -1383,7 +1383,7 @@ static void sunzilog_init_hw(struct uart
+ write_zsreg(channel, R9, up->curregs[R9]);
+ }
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+
+ #ifdef CONFIG_SERIO
+ if (up->flags & (SUNZILOG_FLAG_CONS_KEYB |