diff options
| -rw-r--r-- | drivers/tty/serial/imx.c | 71 |
1 files changed, 52 insertions, 19 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 8f62a3cec23e..883f8a2f4ab5 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -49,6 +49,7 @@ #include <linux/of_device.h> #include <linux/io.h> #include <linux/dma-mapping.h> +#include <linux/kgdb.h> #include <asm/irq.h> #include <linux/platform_data/serial-imx.h> @@ -1507,44 +1508,73 @@ imx_verify_port(struct uart_port *port, struct serial_struct *ser) } #if defined(CONFIG_CONSOLE_POLL) + +#if defined(CONFIG_KGDB_FIQ) +/* + * Prepare the UART to be used from kgdb's NMI support. + */ +static int imx_poll_init(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long flags; + unsigned long temp; + int retval; + + retval = clk_prepare_enable(sport->clk_ipg); + if (retval) + return retval; + retval = clk_prepare_enable(sport->clk_per); + if (retval) + clk_disable_unprepare(sport->clk_ipg); + + imx_setup_ufcr(sport, 0); + + spin_lock_irqsave(&sport->port.lock, flags); + + temp = readl(sport->port.membase + UCR1); + if (is_imx1_uart(sport)) + temp |= IMX1_UCR1_UARTCLKEN; + temp |= UCR1_UARTEN | UCR1_RRDYEN; + temp &= ~(UCR1_TXMPTYEN | UCR1_RTSDEN); + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR2); + temp |= UCR2_RXEN; + writel(temp, sport->port.membase + UCR2); + + spin_unlock_irqrestore(&sport->port.lock, flags); + + /* register the FIQ with kgdb */ + kgdb_register_fiq(sport->port.irq); + + return 0; +} +#endif /* CONFIG_KGDB_FIQ */ + 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 NO_POLL_CHAR; - 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) { - struct imx_port_ucrs old_ucr; unsigned int status; - /* 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); - /* drain */ do { - status = readl(port->membase + USR1); + status = readl_relaxed(port->membase + USR1); } while (~status & USR1_TRDY); /* write */ - writel(c, port->membase + URTX0); + writel_relaxed(c, port->membase + URTX0); /* flush */ do { - status = readl(port->membase + USR2); + status = readl_relaxed(port->membase + USR2); } while (~status & USR2_TXDC); - - /* restore control registers */ - imx_port_ucrs_restore(port, &old_ucr); } #endif @@ -1565,6 +1595,9 @@ static struct uart_ops imx_pops = { .config_port = imx_config_port, .verify_port = imx_verify_port, #if defined(CONFIG_CONSOLE_POLL) +#if defined(CONFIG_KGDB_FIQ) + .poll_init = imx_poll_init, +#endif .poll_get_char = imx_poll_get_char, .poll_put_char = imx_poll_put_char, #endif |