From 8a61f0c70ae65c6b70d13228c3120c73d7425a60 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Wed, 17 Jun 2015 17:35:43 -0300 Subject: [PATCH] serial: imx: Disable irqs before requesting them Disable interrupts before requesting them in order to fix a kernel oops after lauching a kernel via kexec. Tested on a imx6sl-evk board. Signed-off-by: Fabio Estevam Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 2c90dc31bfaa..cddf9026a72b 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1902,7 +1902,7 @@ static int serial_imx_probe(struct platform_device *pdev) { struct imx_port *sport; void __iomem *base; - int ret = 0; + int ret = 0, reg; struct resource *res; int txirq, rxirq, rtsirq; @@ -1957,6 +1957,19 @@ static int serial_imx_probe(struct platform_device *pdev) sport->port.uartclk = clk_get_rate(sport->clk_per); + /* For register access, we only need to enable the ipg clock. */ + ret = clk_prepare_enable(sport->clk_ipg); + if (ret) + return ret; + + /* Disable interrupts before requesting them */ + reg = readl_relaxed(sport->port.membase + UCR1); + reg &= ~(UCR1_ADEN | UCR1_TRDYEN | UCR1_IDEN | UCR1_RRDYEN | + UCR1_TXMPTYEN | UCR1_RTSDEN); + writel_relaxed(reg, sport->port.membase + UCR1); + + clk_disable_unprepare(sport->clk_ipg); + /* * Allocate the IRQ(s) i.MX1 has three interrupts whereas later * chips only have one interrupt. -- 2.20.1