[PATCH v3 0/2] Exynos SoCs: enable support for ARM Architected Timers

[PATCH v3 0/2] Exynos SoCs: enable support for ARM Architected Timers

[Marek Szyprowski]

Dear All,

ARM Architected Timers are present in all CortexA7/A15 based Samsung
Exynos SoCs. So far they were not enabled, because there were some issues
related to their initialization. Samsung Exynos SoCs used custom timer
hardware - Exynos MultiCore Timer. It turned out that enabling MCT it is
also needed to get ARM Architected Timers working, because they both
share some common hardware blocks (global system counter).

This patchset enables support for ARM Architected Timer driver together
with a standard Exynos MultiCore Timer driver, which is kept as a default
timer source on ARM 32bit platforms. Support for ARM architected timers
is essential for enabling proper KVM support on those platforms.

Best regards
Marek Szyprowski
Samsung R&D Institute Poland


Changelog:

v3:
- checked the status of arch timer registers on all Exynos5 SoCs,
  dropped 'not-fw-configured' property on most of them as requested
  by Marc Zyngier
- dropped enabling arch timers on Exynos3250, as there is no benefit from
  that (none of the Exynos3250-based board boots in HYP mode)

v2: https://www.spinics.net/lists/arm-kernel/msg751017.html
- dropped MCT patches (merged to v5.1)
- dropped timer priority change patch (merged to v5.3)

v1: https://www.spinics.net/lists/arm-kernel/msg751018.html
- initial version, covers some MCT patches previously sent as a timer
  rework for Exynos5433


Patch summary:

Marek Szyprowski (2):
  ARM: dts: exynos: Add support ARM architected timers on Exynos5
  ARM: exynos: Enable support for ARM architected timers

 arch/arm/boot/dts/exynos5420-peach-pit.dts | 4 ++++
 arch/arm/boot/dts/exynos54xx.dtsi          | 9 +++++++++
 arch/arm/boot/dts/exynos5800-peach-pi.dts  | 4 ++++
 arch/arm/mach-exynos/Kconfig               | 1 +
 4 files changed, 18 insertions(+)

-- 
2.17.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v3 1/2] ARM: dts: exynos: Add support ARM architected timers on Exynos5

[Marek Szyprowski]

All CortexA7/A15 based Exynos5 SoCs have ARM architected timers, so enable
support for them directly in the base dtsi. None of the known firmware
properly configures CNTFRQ arch timer register, so force clock frequency
to 24MHz, which is the only configuration supported by the remaining
clock drivers so far.

Stock firmware for Peach Pit and Pi Chromebooks also doesn't reset
properly other arch timer registers, so add respective properties
indicating that. Other Exynos5-based boards behaves correctly in this area,
what finally allows to enable support for KVM-based virtualization.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 arch/arm/boot/dts/exynos5420-peach-pit.dts | 4 ++++
 arch/arm/boot/dts/exynos54xx.dtsi          | 9 +++++++++
 arch/arm/boot/dts/exynos5800-peach-pi.dts  | 4 ++++
 3 files changed, 17 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5420-peach-pit.dts b/arch/arm/boot/dts/exynos5420-peach-pit.dts
index f78db6809cca..77e08a4c7300 100644
--- a/arch/arm/boot/dts/exynos5420-peach-pit.dts
+++ b/arch/arm/boot/dts/exynos5420-peach-pit.dts
@@ -1064,6 +1064,10 @@
 	status = "okay";
 };
 
+&timer {
+	arm,cpu-registers-not-fw-configured;
+};
+
 &tmu_cpu0 {
 	vtmu-supply = <&ldo10_reg>;
 };
diff --git a/arch/arm/boot/dts/exynos54xx.dtsi b/arch/arm/boot/dts/exynos54xx.dtsi
index 9c3b63b7cac6..02d34957cd83 100644
--- a/arch/arm/boot/dts/exynos54xx.dtsi
+++ b/arch/arm/boot/dts/exynos54xx.dtsi
@@ -45,6 +45,15 @@
 		status = "disabled";
 	};
 
+	timer: timer {
+		compatible = "arm,armv7-timer";
+		interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
+			     <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
+		clock-frequency = <24000000>;
+	};
+
 	soc: soc {
 		sysram@2020000 {
 			compatible = "mmio-sram";
diff --git a/arch/arm/boot/dts/exynos5800-peach-pi.dts b/arch/arm/boot/dts/exynos5800-peach-pi.dts
index e0f470fe54c8..5e8cec736444 100644
--- a/arch/arm/boot/dts/exynos5800-peach-pi.dts
+++ b/arch/arm/boot/dts/exynos5800-peach-pi.dts
@@ -1033,6 +1033,10 @@
 	status = "okay";
 };
 
+&timer {
+	arm,cpu-registers-not-fw-configured;
+};
+
 &tmu_cpu0 {
 	vtmu-supply = <&ldo10_reg>;
 };
-- 
2.17.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v3 2/2] ARM: exynos: Enable support for ARM architected timers

[Marek Szyprowski]

ARM architected timer can be used together with Exynos MultiCore Timer
driver, so enable support for it. Support for ARM architected timers is
essential for enabling proper KVM support.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 arch/arm/mach-exynos/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
index f83786640f94..9dab1f50a02f 100644
--- a/arch/arm/mach-exynos/Kconfig
+++ b/arch/arm/mach-exynos/Kconfig
@@ -19,6 +19,7 @@ menuconfig ARCH_EXYNOS
 	select EXYNOS_SROM
 	select EXYNOS_PM_DOMAINS if PM_GENERIC_DOMAINS
 	select GPIOLIB
+	select HAVE_ARM_ARCH_TIMER if ARCH_EXYNOS5 && VIRTUALIZATION
 	select HAVE_ARM_SCU if SMP
 	select HAVE_S3C2410_I2C if I2C
 	select HAVE_S3C2410_WATCHDOG if WATCHDOG
-- 
2.17.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v3 2/2] ARM: exynos: Enable support for ARM architected timers

[Chanwoo Choi]

Dear Marek,

On 19. 8. 28. 오후 9:10, Marek Szyprowski wrote:
> ARM architected timer can be used together with Exynos MultiCore Timer
> driver, so enable support for it. Support for ARM architected timers is
> essential for enabling proper KVM support.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  arch/arm/mach-exynos/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
> index f83786640f94..9dab1f50a02f 100644
> --- a/arch/arm/mach-exynos/Kconfig
> +++ b/arch/arm/mach-exynos/Kconfig
> @@ -19,6 +19,7 @@ menuconfig ARCH_EXYNOS
>  	select EXYNOS_SROM
>  	select EXYNOS_PM_DOMAINS if PM_GENERIC_DOMAINS
>  	select GPIOLIB
> +	select HAVE_ARM_ARCH_TIMER if ARCH_EXYNOS5 && VIRTUALIZATION
>  	select HAVE_ARM_SCU if SMP
>  	select HAVE_S3C2410_I2C if I2C
>  	select HAVE_S3C2410_WATCHDOG if WATCHDOG
> 

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>

-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v3 1/2] ARM: dts: exynos: Add support ARM architected timers on Exynos5

[Chanwoo Choi]

Dear Marek,

On 19. 8. 28. 오후 9:10, Marek Szyprowski wrote:
> All CortexA7/A15 based Exynos5 SoCs have ARM architected timers, so enable
> support for them directly in the base dtsi. None of the known firmware
> properly configures CNTFRQ arch timer register, so force clock frequency
> to 24MHz, which is the only configuration supported by the remaining
> clock drivers so far.
> 
> Stock firmware for Peach Pit and Pi Chromebooks also doesn't reset
> properly other arch timer registers, so add respective properties
> indicating that. Other Exynos5-based boards behaves correctly in this area,
> what finally allows to enable support for KVM-based virtualization.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  arch/arm/boot/dts/exynos5420-peach-pit.dts | 4 ++++
>  arch/arm/boot/dts/exynos54xx.dtsi          | 9 +++++++++
>  arch/arm/boot/dts/exynos5800-peach-pi.dts  | 4 ++++
>  3 files changed, 17 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/exynos5420-peach-pit.dts b/arch/arm/boot/dts/exynos5420-peach-pit.dts
> index f78db6809cca..77e08a4c7300 100644
> --- a/arch/arm/boot/dts/exynos5420-peach-pit.dts
> +++ b/arch/arm/boot/dts/exynos5420-peach-pit.dts
> @@ -1064,6 +1064,10 @@
>  	status = "okay";
>  };
>  
> +&timer {
> +	arm,cpu-registers-not-fw-configured;
> +};
> +
>  &tmu_cpu0 {
>  	vtmu-supply = <&ldo10_reg>;
>  };
> diff --git a/arch/arm/boot/dts/exynos54xx.dtsi b/arch/arm/boot/dts/exynos54xx.dtsi
> index 9c3b63b7cac6..02d34957cd83 100644
> --- a/arch/arm/boot/dts/exynos54xx.dtsi
> +++ b/arch/arm/boot/dts/exynos54xx.dtsi
> @@ -45,6 +45,15 @@
>  		status = "disabled";
>  	};
>  
> +	timer: timer {
> +		compatible = "arm,armv7-timer";
> +		interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
> +			     <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
> +			     <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
> +			     <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
> +		clock-frequency = <24000000>;
> +	};
> +
>  	soc: soc {
>  		sysram@2020000 {
>  			compatible = "mmio-sram";
> diff --git a/arch/arm/boot/dts/exynos5800-peach-pi.dts b/arch/arm/boot/dts/exynos5800-peach-pi.dts
> index e0f470fe54c8..5e8cec736444 100644
> --- a/arch/arm/boot/dts/exynos5800-peach-pi.dts
> +++ b/arch/arm/boot/dts/exynos5800-peach-pi.dts
> @@ -1033,6 +1033,10 @@
>  	status = "okay";
>  };
>  
> +&timer {
> +	arm,cpu-registers-not-fw-configured;
> +};
> +
>  &tmu_cpu0 {
>  	vtmu-supply = <&ldo10_reg>;
>  };
> 

I tested it on odroid-xu3 to enable arch-timer for KVM.
In result, I could just initialize KVM on xu3 without problem.

Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v3 2/2] ARM: exynos: Enable support for ARM architected timers

[Krzysztof Kozlowski]

On Wed, Aug 28, 2019 at 02:10:05PM +0200, Marek Szyprowski wrote:
> ARM architected timer can be used together with Exynos MultiCore Timer
> driver, so enable support for it. Support for ARM architected timers is
> essential for enabling proper KVM support.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  arch/arm/mach-exynos/Kconfig | 1 +

Thanks, applied this one only from the set (I will have send another soc
pull request before merge window).

Best regards,
Krzysztof


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH v3 1/2] ARM: dts: exynos: Add support ARM architected timers on Exynos5

[Krzysztof Kozlowski]

On Wed, Aug 28, 2019 at 02:10:04PM +0200, Marek Szyprowski wrote:
> All CortexA7/A15 based Exynos5 SoCs have ARM architected timers, so enable
> support for them directly in the base dtsi. None of the known firmware
> properly configures CNTFRQ arch timer register, so force clock frequency
> to 24MHz, which is the only configuration supported by the remaining
> clock drivers so far.
> 
> Stock firmware for Peach Pit and Pi Chromebooks also doesn't reset
> properly other arch timer registers, so add respective properties
> indicating that. Other Exynos5-based boards behaves correctly in this area,
> what finally allows to enable support for KVM-based virtualization.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  arch/arm/boot/dts/exynos5420-peach-pit.dts | 4 ++++
>  arch/arm/boot/dts/exynos54xx.dtsi          | 9 +++++++++
>  arch/arm/boot/dts/exynos5800-peach-pi.dts  | 4 ++++

Thanks, applied.

Best regards,
Krzysztof


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel