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Diffstat (limited to '')
| -rw-r--r-- | debian/patches-rt/0047-serial-pmac_zilog-Use-port-lock-wrappers.patch | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/debian/patches-rt/0047-serial-pmac_zilog-Use-port-lock-wrappers.patch b/debian/patches-rt/0047-serial-pmac_zilog-Use-port-lock-wrappers.patch new file mode 100644 index 000000000..e4a81157e --- /dev/null +++ b/debian/patches-rt/0047-serial-pmac_zilog-Use-port-lock-wrappers.patch @@ -0,0 +1,232 @@ +From: Thomas Gleixner <tglx@linutronix.de> +Date: Thu, 14 Sep 2023 20:44:04 +0206 +Subject: [PATCH 047/134] serial: pmac_zilog: 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/20230914183831.587273-48-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/pmac_zilog.c | 52 ++++++++++++++++++++-------------------- + 1 file changed, 26 insertions(+), 26 deletions(-) + +--- a/drivers/tty/serial/pmac_zilog.c ++++ b/drivers/tty/serial/pmac_zilog.c +@@ -246,9 +246,9 @@ static bool pmz_receive_chars(struct uar + #endif /* USE_CTRL_O_SYSRQ */ + if (uap->port.sysrq) { + int swallow; +- spin_unlock(&uap->port.lock); ++ uart_port_unlock(&uap->port); + swallow = uart_handle_sysrq_char(&uap->port, ch); +- spin_lock(&uap->port.lock); ++ uart_port_lock(&uap->port); + if (swallow) + goto next_char; + } +@@ -435,7 +435,7 @@ static irqreturn_t pmz_interrupt(int irq + uap_a = pmz_get_port_A(uap); + uap_b = uap_a->mate; + +- spin_lock(&uap_a->port.lock); ++ uart_port_lock(&uap_a->port); + r3 = read_zsreg(uap_a, R3); + + /* Channel A */ +@@ -456,14 +456,14 @@ static irqreturn_t pmz_interrupt(int irq + rc = IRQ_HANDLED; + } + skip_a: +- spin_unlock(&uap_a->port.lock); ++ uart_port_unlock(&uap_a->port); + if (push) + tty_flip_buffer_push(&uap->port.state->port); + + if (!uap_b) + goto out; + +- spin_lock(&uap_b->port.lock); ++ uart_port_lock(&uap_b->port); + push = false; + if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) { + if (!ZS_IS_OPEN(uap_b)) { +@@ -481,7 +481,7 @@ static irqreturn_t pmz_interrupt(int irq + rc = IRQ_HANDLED; + } + skip_b: +- spin_unlock(&uap_b->port.lock); ++ uart_port_unlock(&uap_b->port); + if (push) + tty_flip_buffer_push(&uap->port.state->port); + +@@ -497,9 +497,9 @@ static inline u8 pmz_peek_status(struct + unsigned long flags; + u8 status; + +- spin_lock_irqsave(&uap->port.lock, flags); ++ uart_port_lock_irqsave(&uap->port, &flags); + status = read_zsreg(uap, R0); +- spin_unlock_irqrestore(&uap->port.lock, flags); ++ uart_port_unlock_irqrestore(&uap->port, flags); + + return status; + } +@@ -685,7 +685,7 @@ static void pmz_break_ctl(struct uart_po + else + clear_bits |= SND_BRK; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits; + if (new_reg != uap->curregs[R5]) { +@@ -693,7 +693,7 @@ static void pmz_break_ctl(struct uart_po + write_zsreg(uap, R5, uap->curregs[R5]); + } + +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + + #ifdef CONFIG_PPC_PMAC +@@ -865,18 +865,18 @@ static void pmz_irda_reset(struct uart_p + { + unsigned long flags; + +- spin_lock_irqsave(&uap->port.lock, flags); ++ uart_port_lock_irqsave(&uap->port, &flags); + uap->curregs[R5] |= DTR; + write_zsreg(uap, R5, uap->curregs[R5]); + zssync(uap); +- spin_unlock_irqrestore(&uap->port.lock, flags); ++ uart_port_unlock_irqrestore(&uap->port, flags); + msleep(110); + +- spin_lock_irqsave(&uap->port.lock, flags); ++ uart_port_lock_irqsave(&uap->port, &flags); + uap->curregs[R5] &= ~DTR; + write_zsreg(uap, R5, uap->curregs[R5]); + zssync(uap); +- spin_unlock_irqrestore(&uap->port.lock, flags); ++ uart_port_unlock_irqrestore(&uap->port, flags); + msleep(10); + } + +@@ -896,9 +896,9 @@ static int pmz_startup(struct uart_port + * initialize the chip + */ + if (!ZS_IS_CONS(uap)) { +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + pwr_delay = __pmz_startup(uap); +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line); + if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED, +@@ -921,9 +921,9 @@ static int pmz_startup(struct uart_port + pmz_irda_reset(uap); + + /* Enable interrupt requests for the channel */ +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + pmz_interrupt_control(uap, 1); +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + + return 0; + } +@@ -933,7 +933,7 @@ static void pmz_shutdown(struct uart_por + struct uart_pmac_port *uap = to_pmz(port); + unsigned long flags; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + /* Disable interrupt requests for the channel */ + pmz_interrupt_control(uap, 0); +@@ -948,19 +948,19 @@ static void pmz_shutdown(struct uart_por + pmz_maybe_update_regs(uap); + } + +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + + /* Release interrupt handler */ + free_irq(uap->port.irq, uap); + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + uap->flags &= ~PMACZILOG_FLAG_IS_OPEN; + + if (!ZS_IS_CONS(uap)) + pmz_set_scc_power(uap, 0); /* Shut the chip down */ + +- 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 +@@ -1247,7 +1247,7 @@ static void pmz_set_termios(struct uart_ + struct uart_pmac_port *uap = to_pmz(port); + unsigned long flags; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + /* Disable IRQs on the port */ + pmz_interrupt_control(uap, 0); +@@ -1259,7 +1259,7 @@ static void pmz_set_termios(struct uart_ + if (ZS_IS_OPEN(uap)) + pmz_interrupt_control(uap, 1); + +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + + static const char *pmz_type(struct uart_port *port) +@@ -1896,7 +1896,7 @@ static void pmz_console_write(struct con + struct uart_pmac_port *uap = &pmz_ports[con->index]; + unsigned long flags; + +- spin_lock_irqsave(&uap->port.lock, flags); ++ uart_port_lock_irqsave(&uap->port, &flags); + + /* Turn of interrupts and enable the transmitter. */ + write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB); +@@ -1908,7 +1908,7 @@ static void pmz_console_write(struct con + write_zsreg(uap, R1, uap->curregs[1]); + /* Don't disable the transmitter. */ + +- spin_unlock_irqrestore(&uap->port.lock, flags); ++ uart_port_unlock_irqrestore(&uap->port, flags); + } + + /* |