It's all pretty straightforward, except for TXIM interrupt. The interrupt has meaning "ready to transmit", so it's almost always raised, and the only way to silence it is to mask it. But that's OK, ops->start_tx will unmask it.
Signed-off-by: Anton Vorontsov anton.vorontsov@linaro.org --- drivers/tty/serial/amba-pl011.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index c17923e..378d26b 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1308,6 +1308,18 @@ static void pl010_put_poll_char(struct uart_port *port, writew(ch, uap->port.membase + UART01x_DR); }
+static void pl010_clear_irqs(struct uart_port *port) +{ + struct uart_amba_port *uap = (struct uart_amba_port *)port; + unsigned char __iomem *regs = uap->port.membase; + + writew(readw(regs + UART011_MIS), regs + UART011_ICR); + /* + * There is no way to clear TXIM, this is "ready to transmit IRQ", so + * we simply mask it. ops->start_tx will unmask it. + */ + writew(readw(regs + UART011_IMSC) & ~UART011_TXIM, regs + UART011_IMSC); +} #endif /* CONFIG_CONSOLE_POLL */
static int pl011_startup(struct uart_port *port) @@ -1698,6 +1710,7 @@ static struct uart_ops amba_pl011_pops = { #ifdef CONFIG_CONSOLE_POLL .poll_get_char = pl010_get_poll_char, .poll_put_char = pl010_put_poll_char, + .clear_irqs = pl010_clear_irqs, #endif };