[PATCH 1/2] ARM: multi_v7_defconfig: Enable ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND

[PATCH 1/2] ARM: multi_v7_defconfig: Enable ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND

[Heiko Stübner]

At present on atag based legacy bootloaders, the provided kernel commandline
will be used unchanged, potentially using obscure parameters for outdated
vendor-kernel drivers.

Therefore allow them to be extended by known-good parameters from the
bootargs property of the dtb.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
 arch/arm/configs/multi_v7_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index 1bf198b..16a42a5 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -80,6 +80,7 @@ CONFIG_HIGHPTE=y
 CONFIG_CMA=y
 CONFIG_ARM_APPENDED_DTB=y
 CONFIG_ARM_ATAG_DTB_COMPAT=y
+CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND=y
 CONFIG_KEXEC=y
 CONFIG_CPU_FREQ=y
 CONFIG_CPU_FREQ_STAT_DETAILS=y
-- 
2.0.1

[PATCH 2/2] ARM: dts: rockchip: add bootargs setting the correct serial console

[Heiko Stübner]

Uart2 seems to be designated debug uart for all Rockchip platforms.
On all rk30xx and rk31xx boards I've seen so far, this uart was used
for the console and the rk3288 TRM even describes it as debug uart.

Thus add it to the core SoC dtsi files to not duplicate the same
information on every board.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
This makes a multi_v7_defconfig-based kernel start sucessfully on my
rk3188-radxarock and rk3288-evb

 arch/arm/boot/dts/rk3288.dtsi | 4 ++++
 arch/arm/boot/dts/rk3xxx.dtsi | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/rk3288.dtsi b/arch/arm/boot/dts/rk3288.dtsi
index e7cb008..3950bad 100644
--- a/arch/arm/boot/dts/rk3288.dtsi
+++ b/arch/arm/boot/dts/rk3288.dtsi
@@ -36,6 +36,10 @@
 		serial4 = &uart4;
 	};
 
+	chosen {
+		bootargs = "console=ttyS2,115200";
+	};
+
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
diff --git a/arch/arm/boot/dts/rk3xxx.dtsi b/arch/arm/boot/dts/rk3xxx.dtsi
index 8caf85d..9eeb6cb 100644
--- a/arch/arm/boot/dts/rk3xxx.dtsi
+++ b/arch/arm/boot/dts/rk3xxx.dtsi
@@ -28,6 +28,10 @@
 		i2c4 = &i2c4;
 	};
 
+	chosen {
+		bootargs = "console=ttyS2,115200";
+	};
+
 	xin24m: oscillator {
 		compatible = "fixed-clock";
 		clock-frequency = <24000000>;
-- 
2.0.1

[PATCH 2/2] ARM: dts: rockchip: add bootargs setting the correct serial console

[Arnd Bergmann]

On Monday 04 August 2014, Heiko St?bner wrote:
> Uart2 seems to be designated debug uart for all Rockchip platforms.
> On all rk30xx and rk31xx boards I've seen so far, this uart was used
> for the console and the rk3288 TRM even describes it as debug uart.
> 
> Thus add it to the core SoC dtsi files to not duplicate the same
> information on every board.
> 
> Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Shouldn't this be done through the /aliases node for the port selection
and the current-speed property for the bit rate?

I don't think we normally want to have these overridden by the command
line, even if that's what other platforms do.

	Arnd

[PATCH 2/2] ARM: dts: rockchip: add bootargs setting the correct serial console

[Heiko Stübner]

Am Montag, 4. August 2014, 19:29:36 schrieb Arnd Bergmann:
> On Monday 04 August 2014, Heiko St?bner wrote:
> > Uart2 seems to be designated debug uart for all Rockchip platforms.
> > On all rk30xx and rk31xx boards I've seen so far, this uart was used
> > for the console and the rk3288 TRM even describes it as debug uart.
> > 
> > Thus add it to the core SoC dtsi files to not duplicate the same
> > information on every board.
> > 
> > Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> 
> Shouldn't this be done through the /aliases node for the port selection
> and the current-speed property for the bit rate?

hmm, I'm not sure I understand this ... especially how this would relate to 
aliases.

>From reading around a bit I guess teaching the 8250_dw about 
add_preferred_console and using "linux,stdout-path" would be the better way?


Thanks
Heiko

[PATCH 2/2] ARM: dts: rockchip: add bootargs setting the correct serial console

[Arnd Bergmann]

On Tuesday 05 August 2014, Heiko St?bner wrote:
> Am Montag, 4. August 2014, 19:29:36 schrieb Arnd Bergmann:
> > On Monday 04 August 2014, Heiko St?bner wrote:
> > > Uart2 seems to be designated debug uart for all Rockchip platforms.
> > > On all rk30xx and rk31xx boards I've seen so far, this uart was used
> > > for the console and the rk3288 TRM even describes it as debug uart.
> > > 
> > > Thus add it to the core SoC dtsi files to not duplicate the same
> > > information on every board.
> > > 
> > > Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> > 
> > Shouldn't this be done through the /aliases node for the port selection
> > and the current-speed property for the bit rate?
> 
> hmm, I'm not sure I understand this ... especially how this would relate to 
> aliases.
> 
> From reading around a bit I guess teaching the 8250_dw about 
> add_preferred_console and using "linux,stdout-path" would be the better way?
> 

I didn't realize this was 8250_dw rather than the regular of_serial/8250
driver. Yes, it should use "linux,stdout-path". Ideally we'd do this from
common code somewhere. At the time when I wrote of_serial for PowerPC, we
didn't have to worry about UARTS that are something other than 8250, but
of course now we have plenty of different ones.

	Arnd