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-rw-r--r--debian/patches-rt/0017-serial-amba-pl011-Use-port-lock-wrappers.patch327
1 files changed, 327 insertions, 0 deletions
diff --git a/debian/patches-rt/0017-serial-amba-pl011-Use-port-lock-wrappers.patch b/debian/patches-rt/0017-serial-amba-pl011-Use-port-lock-wrappers.patch
new file mode 100644
index 000000000..2a5e3a85e
--- /dev/null
+++ b/debian/patches-rt/0017-serial-amba-pl011-Use-port-lock-wrappers.patch
@@ -0,0 +1,327 @@
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:43:34 +0206
+Subject: [PATCH 017/134] serial: amba-pl011: 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/20230914183831.587273-18-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/amba-pl011.c | 72 ++++++++++++++++++++--------------------
+ 1 file changed, 36 insertions(+), 36 deletions(-)
+
+--- a/drivers/tty/serial/amba-pl011.c
++++ b/drivers/tty/serial/amba-pl011.c
+@@ -347,9 +347,9 @@ static int pl011_fifo_to_tty(struct uart
+ flag = TTY_FRAME;
+ }
+
+- spin_unlock(&uap->port.lock);
++ uart_port_unlock(&uap->port);
+ sysrq = uart_handle_sysrq_char(&uap->port, ch & 255);
+- spin_lock(&uap->port.lock);
++ uart_port_lock(&uap->port);
+
+ if (!sysrq)
+ uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag);
+@@ -544,7 +544,7 @@ static void pl011_dma_tx_callback(void *
+ unsigned long flags;
+ u16 dmacr;
+
+- spin_lock_irqsave(&uap->port.lock, flags);
++ uart_port_lock_irqsave(&uap->port, &flags);
+ if (uap->dmatx.queued)
+ dma_unmap_single(dmatx->chan->device->dev, dmatx->dma,
+ dmatx->len, DMA_TO_DEVICE);
+@@ -565,7 +565,7 @@ static void pl011_dma_tx_callback(void *
+ if (!(dmacr & UART011_TXDMAE) || uart_tx_stopped(&uap->port) ||
+ uart_circ_empty(&uap->port.state->xmit)) {
+ uap->dmatx.queued = false;
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+ return;
+ }
+
+@@ -576,7 +576,7 @@ static void pl011_dma_tx_callback(void *
+ */
+ pl011_start_tx_pio(uap);
+
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+ }
+
+ /*
+@@ -1004,7 +1004,7 @@ static void pl011_dma_rx_callback(void *
+ * routine to flush out the secondary DMA buffer while
+ * we immediately trigger the next DMA job.
+ */
+- spin_lock_irq(&uap->port.lock);
++ uart_port_lock_irq(&uap->port);
+ /*
+ * Rx data can be taken by the UART interrupts during
+ * the DMA irq handler. So we check the residue here.
+@@ -1020,7 +1020,7 @@ static void pl011_dma_rx_callback(void *
+ ret = pl011_dma_rx_trigger_dma(uap);
+
+ pl011_dma_rx_chars(uap, pending, lastbuf, false);
+- spin_unlock_irq(&uap->port.lock);
++ uart_port_unlock_irq(&uap->port);
+ /*
+ * Do this check after we picked the DMA chars so we don't
+ * get some IRQ immediately from RX.
+@@ -1086,11 +1086,11 @@ static void pl011_dma_rx_poll(struct tim
+ if (jiffies_to_msecs(jiffies - dmarx->last_jiffies)
+ > uap->dmarx.poll_timeout) {
+
+- spin_lock_irqsave(&uap->port.lock, flags);
++ uart_port_lock_irqsave(&uap->port, &flags);
+ pl011_dma_rx_stop(uap);
+ uap->im |= UART011_RXIM;
+ pl011_write(uap->im, uap, REG_IMSC);
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+
+ uap->dmarx.running = false;
+ dmaengine_terminate_all(rxchan);
+@@ -1186,10 +1186,10 @@ static void pl011_dma_shutdown(struct ua
+ while (pl011_read(uap, REG_FR) & uap->vendor->fr_busy)
+ cpu_relax();
+
+- spin_lock_irq(&uap->port.lock);
++ uart_port_lock_irq(&uap->port);
+ uap->dmacr &= ~(UART011_DMAONERR | UART011_RXDMAE | UART011_TXDMAE);
+ pl011_write(uap->dmacr, uap, REG_DMACR);
+- spin_unlock_irq(&uap->port.lock);
++ uart_port_unlock_irq(&uap->port);
+
+ if (uap->using_tx_dma) {
+ /* In theory, this should already be done by pl011_dma_flush_buffer */
+@@ -1370,9 +1370,9 @@ static void pl011_throttle_rx(struct uar
+ {
+ unsigned long flags;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ pl011_stop_rx(port);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static void pl011_enable_ms(struct uart_port *port)
+@@ -1390,7 +1390,7 @@ static void pl011_rx_chars(struct uart_a
+ {
+ pl011_fifo_to_tty(uap);
+
+- spin_unlock(&uap->port.lock);
++ uart_port_unlock(&uap->port);
+ tty_flip_buffer_push(&uap->port.state->port);
+ /*
+ * If we were temporarily out of DMA mode for a while,
+@@ -1415,7 +1415,7 @@ static void pl011_rx_chars(struct uart_a
+ #endif
+ }
+ }
+- spin_lock(&uap->port.lock);
++ uart_port_lock(&uap->port);
+ }
+
+ static bool pl011_tx_char(struct uart_amba_port *uap, unsigned char c,
+@@ -1551,7 +1551,7 @@ static irqreturn_t pl011_int(int irq, vo
+ unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
+ int handled = 0;
+
+- spin_lock_irqsave(&uap->port.lock, flags);
++ uart_port_lock_irqsave(&uap->port, &flags);
+ status = pl011_read(uap, REG_RIS) & uap->im;
+ if (status) {
+ do {
+@@ -1581,7 +1581,7 @@ static irqreturn_t pl011_int(int irq, vo
+ handled = 1;
+ }
+
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+
+ return IRQ_RETVAL(handled);
+ }
+@@ -1653,14 +1653,14 @@ static void pl011_break_ctl(struct uart_
+ unsigned long flags;
+ unsigned int lcr_h;
+
+- spin_lock_irqsave(&uap->port.lock, flags);
++ uart_port_lock_irqsave(&uap->port, &flags);
+ lcr_h = pl011_read(uap, REG_LCRH_TX);
+ if (break_state == -1)
+ lcr_h |= UART01x_LCRH_BRK;
+ else
+ lcr_h &= ~UART01x_LCRH_BRK;
+ pl011_write(lcr_h, uap, REG_LCRH_TX);
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+ }
+
+ #ifdef CONFIG_CONSOLE_POLL
+@@ -1799,7 +1799,7 @@ static void pl011_enable_interrupts(stru
+ unsigned long flags;
+ unsigned int i;
+
+- spin_lock_irqsave(&uap->port.lock, flags);
++ uart_port_lock_irqsave(&uap->port, &flags);
+
+ /* Clear out any spuriously appearing RX interrupts */
+ pl011_write(UART011_RTIS | UART011_RXIS, uap, REG_ICR);
+@@ -1821,7 +1821,7 @@ static void pl011_enable_interrupts(stru
+ if (!pl011_dma_rx_running(uap))
+ uap->im |= UART011_RXIM;
+ pl011_write(uap->im, uap, REG_IMSC);
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+ }
+
+ static void pl011_unthrottle_rx(struct uart_port *port)
+@@ -1829,7 +1829,7 @@ static void pl011_unthrottle_rx(struct u
+ struct uart_amba_port *uap = container_of(port, struct uart_amba_port, port);
+ unsigned long flags;
+
+- spin_lock_irqsave(&uap->port.lock, flags);
++ uart_port_lock_irqsave(&uap->port, &flags);
+
+ uap->im = UART011_RTIM;
+ if (!pl011_dma_rx_running(uap))
+@@ -1837,7 +1837,7 @@ static void pl011_unthrottle_rx(struct u
+
+ pl011_write(uap->im, uap, REG_IMSC);
+
+- spin_unlock_irqrestore(&uap->port.lock, flags);
++ uart_port_unlock_irqrestore(&uap->port, flags);
+ }
+
+ static int pl011_startup(struct uart_port *port)
+@@ -1857,7 +1857,7 @@ static int pl011_startup(struct uart_por
+
+ pl011_write(uap->vendor->ifls, uap, REG_IFLS);
+
+- spin_lock_irq(&uap->port.lock);
++ uart_port_lock_irq(&uap->port);
+
+ cr = pl011_read(uap, REG_CR);
+ cr &= UART011_CR_RTS | UART011_CR_DTR;
+@@ -1868,7 +1868,7 @@ static int pl011_startup(struct uart_por
+
+ pl011_write(cr, uap, REG_CR);
+
+- spin_unlock_irq(&uap->port.lock);
++ uart_port_unlock_irq(&uap->port);
+
+ /*
+ * initialise the old status of the modem signals
+@@ -1929,12 +1929,12 @@ static void pl011_disable_uart(struct ua
+ unsigned int cr;
+
+ uap->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS);
+- spin_lock_irq(&uap->port.lock);
++ uart_port_lock_irq(&uap->port);
+ cr = pl011_read(uap, REG_CR);
+ cr &= UART011_CR_RTS | UART011_CR_DTR;
+ cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
+ pl011_write(cr, uap, REG_CR);
+- spin_unlock_irq(&uap->port.lock);
++ uart_port_unlock_irq(&uap->port);
+
+ /*
+ * disable break condition and fifos
+@@ -1946,14 +1946,14 @@ static void pl011_disable_uart(struct ua
+
+ static void pl011_disable_interrupts(struct uart_amba_port *uap)
+ {
+- spin_lock_irq(&uap->port.lock);
++ uart_port_lock_irq(&uap->port);
+
+ /* mask all interrupts and clear all pending ones */
+ uap->im = 0;
+ pl011_write(uap->im, uap, REG_IMSC);
+ pl011_write(0xffff, uap, REG_ICR);
+
+- spin_unlock_irq(&uap->port.lock);
++ uart_port_unlock_irq(&uap->port);
+ }
+
+ static void pl011_shutdown(struct uart_port *port)
+@@ -2098,7 +2098,7 @@ pl011_set_termios(struct uart_port *port
+
+ bits = tty_get_frame_size(termios->c_cflag);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ /*
+ * Update the per-port timeout.
+@@ -2172,7 +2172,7 @@ pl011_set_termios(struct uart_port *port
+ old_cr |= UART011_CR_RXE;
+ pl011_write(old_cr, uap, REG_CR);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static void
+@@ -2190,10 +2190,10 @@ sbsa_uart_set_termios(struct uart_port *
+ termios->c_cflag &= ~(CMSPAR | CRTSCTS);
+ termios->c_cflag |= CS8 | CLOCAL;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ uart_update_timeout(port, CS8, uap->fixed_baud);
+ pl011_setup_status_masks(port, termios);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static const char *pl011_type(struct uart_port *port)
+@@ -2332,9 +2332,9 @@ pl011_console_write(struct console *co,
+ if (uap->port.sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+- locked = spin_trylock(&uap->port.lock);
++ locked = uart_port_trylock(&uap->port);
+ else
+- spin_lock(&uap->port.lock);
++ uart_port_lock(&uap->port);
+
+ /*
+ * First save the CR then disable the interrupts
+@@ -2360,7 +2360,7 @@ pl011_console_write(struct console *co,
+ pl011_write(old_cr, uap, REG_CR);
+
+ if (locked)
+- spin_unlock(&uap->port.lock);
++ uart_port_unlock(&uap->port);
+ local_irq_restore(flags);
+
+ clk_disable(uap->clk);
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-14 00:29:37 +0000