[PATCH v2 0/4] Add support for the Cortex A5 global timer

[PATCH v2 0/4] Add support for the Cortex A5 global timer

[Matthew Leach]

This patch series adds support for the global timer with the Cortex
A5. This is relatively simple patch series and mainly consists of:

 - Update a check in the drive probe code for an unusable global timer
   to be non-specific to the A9.
 - Add the appropriate device tree node and Kconfig options.
 - Add a compatible node for the specific A5 global timer in the DT
   binding.

Changes since v1
================
- Retain information in the DT binding documentation that the driver
  will only work on a A9 r0p2 and above.

Any comments welcome.
Matt

Matthew Leach (4):
  clocksource: arm_global_timer: Only check for unusable timer on A9
  documentaion: DT: allow a A5 compatible string in global timer
  dts: ca5: add the global timer for the A5
  KConfig: Vexpress: build the ARM_GLOBAL_TIMER with vexpress platform

 Documentation/devicetree/bindings/arm/global_timer.txt |  7 +++++--
 arch/arm/boot/dts/vexpress-v2p-ca5s.dts                | 10 +++++++++-
 arch/arm/mach-vexpress/Kconfig                         |  1 +
 drivers/clocksource/arm_global_timer.c                 |  5 +++--
 4 files changed, 18 insertions(+), 5 deletions(-)

-- 
1.8.5.3

[PATCH v2 1/4] clocksource: arm_global_timer: Only check for unusable timer on A9

[Matthew Leach]

The check for a usable global timer in the probe code does not enquire
which CPU we are currently running on. This can cause the driver to
incorrectly assume we have an unusable global timer if we are running
on a CPU other than A9.

Before checking the CPU revision, ensure we are running on an A9 CPU.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
---
 drivers/clocksource/arm_global_timer.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c
index 0fc31d0..60e5a170 100644
--- a/drivers/clocksource/arm_global_timer.c
+++ b/drivers/clocksource/arm_global_timer.c
@@ -246,11 +246,12 @@ static void __init global_timer_of_register(struct device_node *np)
 	int err = 0;
 
 	/*
-	 * In r2p0 the comparators for each processor with the global timer
+	 * In A9 r2p0 the comparators for each processor with the global timer
 	 * fire when the timer value is greater than or equal to. In previous
 	 * revisions the comparators fired when the timer value was equal to.
 	 */
-	if ((read_cpuid_id() & 0xf0000f) < 0x200000) {
+	if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9
+	    && (read_cpuid_id() & 0xf0000f) < 0x200000) {
 		pr_warn("global-timer: non support for this cpu version.\n");
 		return;
 	}
-- 
1.8.5.3

[PATCH v2 2/4] documentaion: DT: allow a A5 compatible string in global timer

[Matthew Leach]

The global timer is present on the Cortex A5. Add a compatibility
string to the DT binding to allow a Cortex A5 global timer.

Signed-off-by: Matthew Leach <matthew.leach@arm.com>
---
 Documentation/devicetree/bindings/arm/global_timer.txt | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/global_timer.txt b/Documentation/devicetree/bindings/arm/global_timer.txt
index 1e54898..bdae3a8 100644
--- a/Documentation/devicetree/bindings/arm/global_timer.txt
+++ b/Documentation/devicetree/bindings/arm/global_timer.txt
@@ -4,8 +4,11 @@
 
 ** Timer node required properties:
 
-- compatible : Should be "arm,cortex-a9-global-timer"
-		Driver supports versions r2p0 and above.
+- compatible : should contain
+	     * "arm,cortex-a5-global-timer" for Cortex-A5 global timers.
+	     * "arm,cortex-a9-global-timer" for Cortex-A9 global
+	         timers or any compatible implementation. Note: driver
+	         supports versions r2p0 and above.
 
 - interrupts : One interrupt to each core
 
-- 
1.8.5.3

[PATCH v2 3/4] dts: ca5: add the global timer for the A5

[Matthew Leach]

The Cortex A5 contains a global timer: add the appropriate device tree
node.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
---
 arch/arm/boot/dts/vexpress-v2p-ca5s.dts | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/vexpress-v2p-ca5s.dts b/arch/arm/boot/dts/vexpress-v2p-ca5s.dts
index c544a55..d2709b7 100644
--- a/arch/arm/boot/dts/vexpress-v2p-ca5s.dts
+++ b/arch/arm/boot/dts/vexpress-v2p-ca5s.dts
@@ -88,6 +88,14 @@
 		interrupts = <1 13 0x304>;
 	};
 
+	timer at 2c000200 {
+		compatible = "arm,cortex-a5-global-timer",
+		             "arm,cortex-a9-global-timer";
+		reg = <0x2c000200 0x20>;
+		interrupts = <1 11 0x304>;
+		clocks = <&oscclk0>;
+	};
+
 	watchdog at 2c000620 {
 		compatible = "arm,cortex-a5-twd-wdt";
 		reg = <0x2c000620 0x20>;
@@ -120,7 +128,7 @@
 		compatible = "arm,vexpress,config-bus";
 		arm,vexpress,config-bridge = <&v2m_sysreg>;
 
-		osc at 0 {
+		oscclk0: osc at 0 {
 			/* CPU and internal AXI reference clock */
 			compatible = "arm,vexpress-osc";
 			arm,vexpress-sysreg,func = <1 0>;
-- 
1.8.5.3

[PATCH v2 4/4] KConfig: Vexpress: build the ARM_GLOBAL_TIMER with vexpress platform

[Matthew Leach]

The Cortex A5 now contains bindings for the global timer
driver. Ensure that the driver is built with a vexpress platform.

Signed-off-by: Matthew Leach <matthew.leach@arm.com>
---
 arch/arm/mach-vexpress/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/mach-vexpress/Kconfig b/arch/arm/mach-vexpress/Kconfig
index 4a70be4..4fb2a65 100644
--- a/arch/arm/mach-vexpress/Kconfig
+++ b/arch/arm/mach-vexpress/Kconfig
@@ -4,6 +4,7 @@ config ARCH_VEXPRESS
 	select ARCH_SUPPORTS_BIG_ENDIAN
 	select ARM_AMBA
 	select ARM_GIC
+	select ARM_GLOBAL_TIMER
 	select ARM_TIMER_SP804
 	select COMMON_CLK
 	select COMMON_CLK_VERSATILE
-- 
1.8.5.3

[PATCH v2 2/4] documentaion: DT: allow a A5 compatible string in global timer

[Rob Herring]

On Fri, Mar 14, 2014 at 5:18 AM, Matthew Leach <matthew.leach@arm.com> wrote:
> The global timer is present on the Cortex A5. Add a compatibility
> string to the DT binding to allow a Cortex A5 global timer.
>
> Signed-off-by: Matthew Leach <matthew.leach@arm.com>

Acked-by: Rob Herring <robh@kernel.org>

> ---
>  Documentation/devicetree/bindings/arm/global_timer.txt | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/arm/global_timer.txt b/Documentation/devicetree/bindings/arm/global_timer.txt
> index 1e54898..bdae3a8 100644
> --- a/Documentation/devicetree/bindings/arm/global_timer.txt
> +++ b/Documentation/devicetree/bindings/arm/global_timer.txt
> @@ -4,8 +4,11 @@
>
>  ** Timer node required properties:
>
> -- compatible : Should be "arm,cortex-a9-global-timer"
> -               Driver supports versions r2p0 and above.
> +- compatible : should contain
> +            * "arm,cortex-a5-global-timer" for Cortex-A5 global timers.
> +            * "arm,cortex-a9-global-timer" for Cortex-A9 global
> +                timers or any compatible implementation. Note: driver
> +                supports versions r2p0 and above.
>
>  - interrupts : One interrupt to each core
>
> --
> 1.8.5.3
>
>

[PATCH v2 1/4] clocksource: arm_global_timer: Only check for unusable timer on A9

[Daniel Lezcano]

On 03/14/2014 11:18 AM, Matthew Leach wrote:
> The check for a usable global timer in the probe code does not enquire
> which CPU we are currently running on. This can cause the driver to
> incorrectly assume we have an unusable global timer if we are running
> on a CPU other than A9.
>
> Before checking the CPU revision, ensure we are running on an A9 CPU.
>
> Acked-by: Will Deacon <will.deacon@arm.com>
> Signed-off-by: Matthew Leach <matthew.leach@arm.com>
> ---
>   drivers/clocksource/arm_global_timer.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c
> index 0fc31d0..60e5a170 100644
> --- a/drivers/clocksource/arm_global_timer.c
> +++ b/drivers/clocksource/arm_global_timer.c
> @@ -246,11 +246,12 @@ static void __init global_timer_of_register(struct device_node *np)
>   	int err = 0;
>
>   	/*
> -	 * In r2p0 the comparators for each processor with the global timer
> +	 * In A9 r2p0 the comparators for each processor with the global timer
>   	 * fire when the timer value is greater than or equal to. In previous
>   	 * revisions the comparators fired when the timer value was equal to.
>   	 */
> -	if ((read_cpuid_id() & 0xf0000f) < 0x200000) {
> +	if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9
> +	    && (read_cpuid_id() & 0xf0000f) < 0x200000) {
>   		pr_warn("global-timer: non support for this cpu version.\n");
>   		return;
>   	}

Applied on my tree for 3.16


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