[RT,1/1] tty/serial/sifive: Make the locking RT aware

From: ende . tan
Date: Tue Dec 03 2024 - 15:15:08 EST


From: Tan En De <ende.tan@xxxxxxxxxxxxxxxx>

The lock is a sleeping lock and local_irq_save() is not the optimsation
we are looking for. Redo it to make it work on -RT and non-RT.

Signed-off-by: Tan En De <ende.tan@xxxxxxxxxxxxxxxx>
Signed-off-by: Tan Ley Foon <leyfoon.tan@xxxxxxxxxxxxxxxx>
---
drivers/tty/serial/sifive.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c
index b296e57a9dee..074c9f392634 100644
--- a/drivers/tty/serial/sifive.c
+++ b/drivers/tty/serial/sifive.c
@@ -791,13 +791,10 @@ static void sifive_serial_console_write(struct console *co, const char *s,
if (!ssp)
return;

- local_irq_save(flags);
- if (ssp->port.sysrq)
- locked = 0;
- else if (oops_in_progress)
- locked = uart_port_trylock(&ssp->port);
+ if (ssp->port.sysrq || oops_in_progress)
+ locked = uart_port_trylock_irqsave(&ssp->port, &flags);
else
- uart_port_lock(&ssp->port);
+ uart_port_lock_irqsave(&ssp->port, &flags);

ier = __ssp_readl(ssp, SIFIVE_SERIAL_IE_OFFS);
__ssp_writel(0, SIFIVE_SERIAL_IE_OFFS, ssp);
@@ -807,8 +804,7 @@ static void sifive_serial_console_write(struct console *co, const char *s,
__ssp_writel(ier, SIFIVE_SERIAL_IE_OFFS, ssp);

if (locked)
- uart_port_unlock(&ssp->port);
- local_irq_restore(flags);
+ uart_port_unlock_irqrestore(&ssp->port, flags);
}

static int sifive_serial_console_setup(struct console *co, char *options)
--
2.34.1