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-rw-r--r--debian/patches-rt/0060-serial-sh-sci-Use-port-lock-wrappers.patch302
1 files changed, 302 insertions, 0 deletions
diff --git a/debian/patches-rt/0060-serial-sh-sci-Use-port-lock-wrappers.patch b/debian/patches-rt/0060-serial-sh-sci-Use-port-lock-wrappers.patch
new file mode 100644
index 0000000000..6d039c6658
--- /dev/null
+++ b/debian/patches-rt/0060-serial-sh-sci-Use-port-lock-wrappers.patch
@@ -0,0 +1,302 @@
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:44:17 +0206
+Subject: [PATCH 060/134] serial: sh-sci: 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/20230914183831.587273-61-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/sh-sci.c | 68 ++++++++++++++++++++++----------------------
+ 1 file changed, 34 insertions(+), 34 deletions(-)
+
+--- a/drivers/tty/serial/sh-sci.c
++++ b/drivers/tty/serial/sh-sci.c
+@@ -1205,7 +1205,7 @@ static void sci_dma_tx_complete(void *ar
+
+ dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ uart_xmit_advance(port, s->tx_dma_len);
+
+@@ -1229,7 +1229,7 @@ static void sci_dma_tx_complete(void *ar
+ }
+ }
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ /* Locking: called with port lock held */
+@@ -1320,7 +1320,7 @@ static void sci_dma_rx_complete(void *ar
+ dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
+ s->active_rx);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ active = sci_dma_rx_find_active(s);
+ if (active >= 0)
+@@ -1347,20 +1347,20 @@ static void sci_dma_rx_complete(void *ar
+
+ dma_async_issue_pending(chan);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
+ __func__, s->cookie_rx[active], active, s->active_rx);
+ return;
+
+ fail:
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
+ /* Switch to PIO */
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ dmaengine_terminate_async(chan);
+ sci_dma_rx_chan_invalidate(s);
+ sci_dma_rx_reenable_irq(s);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static void sci_dma_tx_release(struct sci_port *s)
+@@ -1409,13 +1409,13 @@ static int sci_dma_rx_submit(struct sci_
+ fail:
+ /* Switch to PIO */
+ if (!port_lock_held)
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ if (i)
+ dmaengine_terminate_async(chan);
+ sci_dma_rx_chan_invalidate(s);
+ sci_start_rx(port);
+ if (!port_lock_held)
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ return -EAGAIN;
+ }
+
+@@ -1437,14 +1437,14 @@ static void sci_dma_tx_work_fn(struct wo
+ * transmit till the end, and then the rest. Take the port lock to get a
+ * consistent xmit buffer state.
+ */
+- spin_lock_irq(&port->lock);
++ uart_port_lock_irq(port);
+ head = xmit->head;
+ tail = xmit->tail;
+ buf = s->tx_dma_addr + tail;
+ s->tx_dma_len = CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE);
+ if (!s->tx_dma_len) {
+ /* Transmit buffer has been flushed */
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ return;
+ }
+
+@@ -1452,7 +1452,7 @@ static void sci_dma_tx_work_fn(struct wo
+ DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc) {
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
+ goto switch_to_pio;
+ }
+@@ -1464,12 +1464,12 @@ static void sci_dma_tx_work_fn(struct wo
+ desc->callback_param = s;
+ s->cookie_tx = dmaengine_submit(desc);
+ if (dma_submit_error(s->cookie_tx)) {
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
+ goto switch_to_pio;
+ }
+
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
+ __func__, xmit->buf, tail, head, s->cookie_tx);
+
+@@ -1477,10 +1477,10 @@ static void sci_dma_tx_work_fn(struct wo
+ return;
+
+ switch_to_pio:
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ s->chan_tx = NULL;
+ sci_start_tx(port);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ return;
+ }
+
+@@ -1497,17 +1497,17 @@ static enum hrtimer_restart sci_dma_rx_t
+
+ dev_dbg(port->dev, "DMA Rx timed out\n");
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ active = sci_dma_rx_find_active(s);
+ if (active < 0) {
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ return HRTIMER_NORESTART;
+ }
+
+ status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
+ if (status == DMA_COMPLETE) {
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
+ s->active_rx, active);
+
+@@ -1525,7 +1525,7 @@ static enum hrtimer_restart sci_dma_rx_t
+ */
+ status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
+ if (status == DMA_COMPLETE) {
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
+ return HRTIMER_NORESTART;
+ }
+@@ -1546,7 +1546,7 @@ static enum hrtimer_restart sci_dma_rx_t
+
+ sci_dma_rx_reenable_irq(s);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ return HRTIMER_NORESTART;
+ }
+@@ -1770,9 +1770,9 @@ static irqreturn_t sci_tx_interrupt(int
+ struct uart_port *port = ptr;
+ unsigned long flags;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ sci_transmit_chars(port);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ return IRQ_HANDLED;
+ }
+@@ -1786,11 +1786,11 @@ static irqreturn_t sci_tx_end_interrupt(
+ if (port->type != PORT_SCI)
+ return sci_tx_interrupt(irq, ptr);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ ctrl = serial_port_in(port, SCSCR);
+ ctrl &= ~(SCSCR_TE | SCSCR_TEIE);
+ serial_port_out(port, SCSCR, ctrl);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ return IRQ_HANDLED;
+ }
+@@ -2187,7 +2187,7 @@ static void sci_break_ctl(struct uart_po
+ return;
+ }
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ scsptr = serial_port_in(port, SCSPTR);
+ scscr = serial_port_in(port, SCSCR);
+
+@@ -2201,7 +2201,7 @@ static void sci_break_ctl(struct uart_po
+
+ serial_port_out(port, SCSPTR, scsptr);
+ serial_port_out(port, SCSCR, scscr);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static int sci_startup(struct uart_port *port)
+@@ -2233,7 +2233,7 @@ static void sci_shutdown(struct uart_por
+ s->autorts = false;
+ mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ sci_stop_rx(port);
+ sci_stop_tx(port);
+ /*
+@@ -2243,7 +2243,7 @@ static void sci_shutdown(struct uart_por
+ scr = serial_port_in(port, SCSCR);
+ serial_port_out(port, SCSCR, scr &
+ (SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ #ifdef CONFIG_SERIAL_SH_SCI_DMA
+ if (s->chan_rx_saved) {
+@@ -2545,7 +2545,7 @@ static void sci_set_termios(struct uart_
+ serial_port_out(port, SCCKS, sccks);
+ }
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ sci_reset(port);
+
+@@ -2667,7 +2667,7 @@ static void sci_set_termios(struct uart_
+ if ((termios->c_cflag & CREAD) != 0)
+ sci_start_rx(port);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ sci_port_disable(s);
+
+@@ -3052,9 +3052,9 @@ static void serial_console_write(struct
+ if (port->sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+- locked = spin_trylock_irqsave(&port->lock, flags);
++ locked = uart_port_trylock_irqsave(port, &flags);
+ else
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ /* first save SCSCR then disable interrupts, keep clock source */
+ ctrl = serial_port_in(port, SCSCR);
+@@ -3074,7 +3074,7 @@ static void serial_console_write(struct
+ serial_port_out(port, SCSCR, ctrl);
+
+ if (locked)
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static int serial_console_setup(struct console *co, char *options)
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-10 23:43:32 +0000