191 lines
6.3 KiB
Diff
191 lines
6.3 KiB
Diff
From a6e8aee3001c0312bb7e408bf47ce1ab3cfb32ab Mon Sep 17 00:00:00 2001
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From: Thomas Gleixner <tglx@linutronix.de>
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Date: Thu, 14 Sep 2023 20:43:58 +0206
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Subject: [PATCH 067/196] serial: msm: Use port lock wrappers
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When a serial port is used for kernel console output, then all
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modifications to the UART registers which are done from other contexts,
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e.g. getty, termios, are interference points for the kernel console.
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So far this has been ignored and the printk output is based on the
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principle of hope. The rework of the console infrastructure which aims to
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support threaded and atomic consoles, requires to mark sections which
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modify the UART registers as unsafe. This allows the atomic write function
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to make informed decisions and eventually to restore operational state. It
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also allows to prevent the regular UART code from modifying UART registers
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while printk output is in progress.
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All modifications of UART registers are guarded by the UART port lock,
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which provides an obvious synchronization point with the console
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infrastructure.
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To avoid adding this functionality to all UART drivers, wrap the
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spin_[un]lock*() invocations for uart_port::lock into helper functions
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which just contain the spin_[un]lock*() invocations for now. In a
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subsequent step these helpers will gain the console synchronization
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mechanisms.
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Converted with coccinelle. No functional change.
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Reviewed-by: Bjorn Andersson <quic_bjorande@quicinc.com>
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Signed-off-by: John Ogness <john.ogness@linutronix.de>
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Link: https://lore.kernel.org/r/20230914183831.587273-42-john.ogness@linutronix.de
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Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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drivers/tty/serial/msm_serial.c | 38 ++++++++++++++++-----------------
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1 file changed, 19 insertions(+), 19 deletions(-)
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diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
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index 90953e679e38..597264b546fd 100644
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--- a/drivers/tty/serial/msm_serial.c
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+++ b/drivers/tty/serial/msm_serial.c
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@@ -444,7 +444,7 @@ static void msm_complete_tx_dma(void *args)
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unsigned int count;
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u32 val;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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/* Already stopped */
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if (!dma->count)
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@@ -476,7 +476,7 @@ static void msm_complete_tx_dma(void *args)
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msm_handle_tx(port);
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done:
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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}
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static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
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@@ -549,7 +549,7 @@ static void msm_complete_rx_dma(void *args)
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unsigned long flags;
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u32 val;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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/* Already stopped */
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if (!dma->count)
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@@ -587,16 +587,16 @@ static void msm_complete_rx_dma(void *args)
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if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
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flag = TTY_NORMAL;
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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sysrq = uart_handle_sysrq_char(port, dma->virt[i]);
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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if (!sysrq)
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tty_insert_flip_char(tport, dma->virt[i], flag);
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}
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msm_start_rx_dma(msm_port);
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done:
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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if (count)
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tty_flip_buffer_push(tport);
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@@ -762,9 +762,9 @@ static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
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if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
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flag = TTY_NORMAL;
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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sysrq = uart_handle_sysrq_char(port, buf[i]);
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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if (!sysrq)
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tty_insert_flip_char(tport, buf[i], flag);
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}
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@@ -824,9 +824,9 @@ static void msm_handle_rx(struct uart_port *port)
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else if (sr & MSM_UART_SR_PAR_FRAME_ERR)
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flag = TTY_FRAME;
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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sysrq = uart_handle_sysrq_char(port, c);
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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if (!sysrq)
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tty_insert_flip_char(tport, c, flag);
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}
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@@ -951,7 +951,7 @@ static irqreturn_t msm_uart_irq(int irq, void *dev_id)
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unsigned int misr;
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u32 val;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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misr = msm_read(port, MSM_UART_MISR);
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msm_write(port, 0, MSM_UART_IMR); /* disable interrupt */
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@@ -983,7 +983,7 @@ static irqreturn_t msm_uart_irq(int irq, void *dev_id)
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msm_handle_delta_cts(port);
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msm_write(port, msm_port->imr, MSM_UART_IMR); /* restore interrupt */
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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return IRQ_HANDLED;
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}
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@@ -1128,13 +1128,13 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
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unsigned long flags, rate;
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flags = *saved_flags;
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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entry = msm_find_best_baud(port, baud, &rate);
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clk_set_rate(msm_port->clk, rate);
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baud = rate / 16 / entry->divisor;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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*saved_flags = flags;
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port->uartclk = rate;
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@@ -1266,7 +1266,7 @@ static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
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unsigned long flags;
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unsigned int baud, mr;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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if (dma->chan) /* Terminate if any */
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msm_stop_dma(port, dma);
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@@ -1338,7 +1338,7 @@ static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
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/* Try to use DMA */
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msm_start_rx_dma(msm_port);
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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}
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static const char *msm_type(struct uart_port *port)
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@@ -1620,9 +1620,9 @@ static void __msm_console_write(struct uart_port *port, const char *s,
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if (port->sysrq)
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locked = 0;
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else if (oops_in_progress)
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- locked = spin_trylock(&port->lock);
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+ locked = uart_port_trylock(port);
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else
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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if (is_uartdm)
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msm_reset_dm_count(port, count);
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@@ -1661,7 +1661,7 @@ static void __msm_console_write(struct uart_port *port, const char *s,
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}
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if (locked)
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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local_irq_restore(flags);
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}
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--
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2.43.2
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