From 3487b074a742bc3300683e91e3ade383b659fbe9 Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Tue, 4 Dec 2012 18:04:59 +0100 Subject: [PATCH] arm: mvebu: Use dw-apb-uart instead of ns16650 as UART driver The UART controller used in the Armada 370 and Armada XP SoCs is the Synopsys DesignWare 8250 (aka Synopsys DesignWare ABP UART). The improper use of the ns16550 can lead to a kernel oops during boot if a character is sent to the UART before the initialization of the driver. The DW APB has an extra interrupt that gets raised when writing to the LCR when busy. This explains why we need to use dw-apb-uart driver to handle this. Signed-off-by: Gregory CLEMENT --- arch/arm/boot/dts/armada-370-xp.dtsi | 6 ++++-- arch/arm/boot/dts/armada-xp.dtsi | 6 ++++-- arch/arm/configs/mvebu_defconfig | 1 + 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/arm/boot/dts/armada-370-xp.dtsi b/arch/arm/boot/dts/armada-370-xp.dtsi index cf6c48a..4c0abe8 100644 --- a/arch/arm/boot/dts/armada-370-xp.dtsi +++ b/arch/arm/boot/dts/armada-370-xp.dtsi @@ -50,17 +50,19 @@ ranges; serial@d0012000 { - compatible = "ns16550"; + compatible = "snps,dw-apb-uart"; reg = <0xd0012000 0x100>; reg-shift = <2>; interrupts = <41>; + reg-io-width = <4>; status = "disabled"; }; serial@d0012100 { - compatible = "ns16550"; + compatible = "snps,dw-apb-uart"; reg = <0xd0012100 0x100>; reg-shift = <2>; interrupts = <42>; + reg-io-width = <4>; status = "disabled"; }; diff --git a/arch/arm/boot/dts/armada-xp.dtsi b/arch/arm/boot/dts/armada-xp.dtsi index 367aa3f..8a85ffe 100644 --- a/arch/arm/boot/dts/armada-xp.dtsi +++ b/arch/arm/boot/dts/armada-xp.dtsi @@ -42,17 +42,19 @@ soc { serial@d0012200 { - compatible = "ns16550"; + compatible = "snps,dw-apb-uart"; reg = <0xd0012200 0x100>; reg-shift = <2>; interrupts = <43>; + reg-io-width = <4>; status = "disabled"; }; serial@d0012300 { - compatible = "ns16550"; + compatible = "snps,dw-apb-uart"; reg = <0xd0012300 0x100>; reg-shift = <2>; interrupts = <44>; + reg-io-width = <4>; status = "disabled"; }; diff --git a/arch/arm/configs/mvebu_defconfig b/arch/arm/configs/mvebu_defconfig index a702fb3..3ba35f1 100644 --- a/arch/arm/configs/mvebu_defconfig +++ b/arch/arm/configs/mvebu_defconfig @@ -34,6 +34,7 @@ CONFIG_MARVELL_PHY=y CONFIG_SERIAL_8250=y CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_OF_PLATFORM=y +CONFIG_SERIAL_8250_DW=y CONFIG_I2C=y CONFIG_I2C_MV64XXX=y CONFIG_GPIOLIB=y -- 1.7.10.4