imx_put_poll_char() has been simplified to remove the code to disable
interrupts. The present code can corrupt register state when re-entered
from FIQ handler.
Switch to _relaxed() MMIO functions (which are safe for polled I/O and
needed to avoid taking spin locks).
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Huang Shijie <b32955@freescale.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
#if defined(CONFIG_CONSOLE_POLL)
static int imx_poll_get_char(struct uart_port *port)
{
#if defined(CONFIG_CONSOLE_POLL)
static int imx_poll_get_char(struct uart_port *port)
{
- if (!(readl(port->membase + USR2) & USR2_RDR))
+ if (!(readl_relaxed(port->membase + USR2) & USR2_RDR))
- return readl(port->membase + URXD0) & URXD_RX_DATA;
+ return readl_relaxed(port->membase + URXD0) & URXD_RX_DATA;
}
static void imx_poll_put_char(struct uart_port *port, unsigned char c)
{
}
static void imx_poll_put_char(struct uart_port *port, unsigned char c)
{
- struct imx_port_ucrs old_ucr;
- /* save control registers */
- imx_port_ucrs_save(port, &old_ucr);
-
- /* disable interrupts */
- writel(UCR1_UARTEN, port->membase + UCR1);
- writel(old_ucr.ucr2 & ~(UCR2_ATEN | UCR2_RTSEN | UCR2_ESCI),
- port->membase + UCR2);
- writel(old_ucr.ucr3 & ~(UCR3_DCD | UCR3_RI | UCR3_DTREN),
- port->membase + UCR3);
-
- status = readl(port->membase + USR1);
+ status = readl_relaxed(port->membase + USR1);
} while (~status & USR1_TRDY);
/* write */
} while (~status & USR1_TRDY);
/* write */
- writel(c, port->membase + URTX0);
+ writel_relaxed(c, port->membase + URTX0);
- status = readl(port->membase + USR2);
+ status = readl_relaxed(port->membase + USR2);
} while (~status & USR2_TXDC);
} while (~status & USR2_TXDC);
-
- /* restore control registers */
- imx_port_ucrs_restore(port, &old_ucr);