[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[Fabio Estevam]

From: Fabio Estevam <fabio.estevam@nxp.com>

As per the i.MX53 Reference Manual add an entry for the
'ARM platform' region in the device tree.

This is needed for accessing the ARM_GPC register to set the
DBGEN bit, so that the debug clocks can be turned on.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
---
 arch/arm/boot/dts/imx53.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
index 1a7a7bb..a70fbf4 100644
--- a/arch/arm/boot/dts/imx53.dtsi
+++ b/arch/arm/boot/dts/imx53.dtsi
@@ -672,6 +672,11 @@
 				status = "disabled";
 			};
 
+			arm_platform: arm-platform at 63fa0000 {
+				compatible = "fsl,imx53-arm-plat", "fsl,imx51-arm-plat";
+				reg = <0x63fa0000 0x28>;
+			};
+
 			owire: owire at 63fa4000 {
 				compatible = "fsl,imx53-owire", "fsl,imx21-owire";
 				reg = <0x63fa4000 0x4000>;
-- 
2.7.4

[PATCH 2/3] ARM: dts: imx53: Add a label for the PMU node

[Fabio Estevam]

From: Fabio Estevam <fabio.estevam@nxp.com>

Add a label for the PMU node so that the board dts may be able to
pass the 'secure-reg-access' property like this:

&pmu {
	secure-reg-access;
};

This also makes it consistent with the PMU node in imx6qdl.dtsi

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
---
 arch/arm/boot/dts/imx53.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
index a70fbf4..263bd39f 100644
--- a/arch/arm/boot/dts/imx53.dtsi
+++ b/arch/arm/boot/dts/imx53.dtsi
@@ -113,7 +113,7 @@
 		};
 	};
 
-	pmu {
+	pmu: pmu {
 		compatible = "arm,cortex-a8-pmu";
 		interrupt-parent = <&tzic>;
 		interrupts = <77>;
-- 
2.7.4

[PATCH 3/3] ARM: mx5: Set the DBGEN bit in ARM_GPC register

[Fabio Estevam]

From: Fabio Estevam <fabio.estevam@nxp.com>

On i.MX51/i.MX53 it is necessery to set the DBGEN bit in 
ARM_GPC register in order to turn on the debug clocks.

The DBGEN bit of ARM_GPC register has the following description
in the i.MX53 Reference Manual:

"This allows the user to manually activate clocks within the debug
system. This register bit directly controls the platform's dbgen_out
output signal which connects to the DAP_SYS to enable all debug clocks.
Once enabled, the clocks cannot be disabled except by asserting the
disable_trace input of the DAP_SYS."

Based on a previous patch from Sebastian Reichel.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
---
 arch/arm/mach-imx/common.h     |  1 +
 arch/arm/mach-imx/cpu-imx5.c   | 38 ++++++++++++++++++++++++++++++++++++++
 arch/arm/mach-imx/mach-imx53.c |  2 ++
 3 files changed, 41 insertions(+)

diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
index c8d68e9..db78329 100644
--- a/arch/arm/mach-imx/common.h
+++ b/arch/arm/mach-imx/common.h
@@ -62,6 +62,7 @@ void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw);
 void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw);
 void imx25_pm_init(void);
 void imx27_pm_init(void);
+void imx5_pmu_init(void);
 
 enum mxc_cpu_pwr_mode {
 	WAIT_CLOCKED,		/* wfi only */
diff --git a/arch/arm/mach-imx/cpu-imx5.c b/arch/arm/mach-imx/cpu-imx5.c
index 4f2d1c7..6c5a055 100644
--- a/arch/arm/mach-imx/cpu-imx5.c
+++ b/arch/arm/mach-imx/cpu-imx5.c
@@ -117,3 +117,41 @@ int mx53_revision(void)
 	return mx5_cpu_rev;
 }
 EXPORT_SYMBOL(mx53_revision);
+
+#define ARM_GPC		0x4
+#define DBGEN		BIT(16)
+
+/*
+ * This enables the DBGEN bit in ARM_GPC register, which is
+ * required for accessing some performance counter features.
+ * Technically it is only required while perf is used, but to
+ * keep the source code simple we just enable it all the time
+ * when the kernel configuration allows using the feature.
+ */
+void imx5_pmu_init(void)
+{
+	void __iomem *arm_plat_base;
+	struct device_node *np;
+	u32 gpc;
+
+	if (!IS_ENABLED(CONFIG_ARM_PMU))
+		return;
+
+	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a8-pmu");
+	if (!np)
+		return;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,imx51-arm-plat");
+	if (!np)
+		return;
+
+	arm_plat_base = of_iomap(np, 0);
+	if (!arm_plat_base) {
+		pr_warn("Unable to map ARM platform registers\n");
+		return;
+	}
+
+	gpc = readl_relaxed(arm_plat_base + ARM_GPC);
+	gpc |= DBGEN;
+	writel_relaxed(gpc, arm_plat_base + ARM_GPC);
+}
diff --git a/arch/arm/mach-imx/mach-imx53.c b/arch/arm/mach-imx/mach-imx53.c
index 07c2e8d..15fba89 100644
--- a/arch/arm/mach-imx/mach-imx53.c
+++ b/arch/arm/mach-imx/mach-imx53.c
@@ -32,6 +32,8 @@ static void __init imx53_dt_init(void)
 {
 	imx_src_init();
 
+	imx5_pmu_init();
+
 	imx_aips_allow_unprivileged_access("fsl,imx53-aipstz");
 }
 
-- 
2.7.4

[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[Sebastian Reichel]

Hi,

On Mon, Jun 18, 2018 at 10:52:17AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam@nxp.com>
> 
> As per the i.MX53 Reference Manual add an entry for the
> 'ARM platform' region in the device tree.
> 
> This is needed for accessing the ARM_GPC register to set the
> DBGEN bit, so that the debug clocks can be turned on.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>

Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

-- Sebastian

> ---
>  arch/arm/boot/dts/imx53.dtsi | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
> index 1a7a7bb..a70fbf4 100644
> --- a/arch/arm/boot/dts/imx53.dtsi
> +++ b/arch/arm/boot/dts/imx53.dtsi
> @@ -672,6 +672,11 @@
>  				status = "disabled";
>  			};
>  
> +			arm_platform: arm-platform at 63fa0000 {
> +				compatible = "fsl,imx53-arm-plat", "fsl,imx51-arm-plat";
> +				reg = <0x63fa0000 0x28>;
> +			};
> +
>  			owire: owire at 63fa4000 {
>  				compatible = "fsl,imx53-owire", "fsl,imx21-owire";
>  				reg = <0x63fa4000 0x4000>;
> -- 
> 2.7.4
> 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20180619/35578c63/attachment.sig>

[PATCH 2/3] ARM: dts: imx53: Add a label for the PMU node

[Sebastian Reichel]

Hi,

On Mon, Jun 18, 2018 at 10:52:18AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam@nxp.com>
> 
> Add a label for the PMU node so that the board dts may be able to
> pass the 'secure-reg-access' property like this:
> 
> &pmu {
> 	secure-reg-access;
> };
> 
> This also makes it consistent with the PMU node in imx6qdl.dtsi
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
> ---

Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

-- Sebastian

>  arch/arm/boot/dts/imx53.dtsi | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
> index a70fbf4..263bd39f 100644
> --- a/arch/arm/boot/dts/imx53.dtsi
> +++ b/arch/arm/boot/dts/imx53.dtsi
> @@ -113,7 +113,7 @@
>  		};
>  	};
>  
> -	pmu {
> +	pmu: pmu {
>  		compatible = "arm,cortex-a8-pmu";
>  		interrupt-parent = <&tzic>;
>  		interrupts = <77>;
> -- 
> 2.7.4
> 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20180619/46dda09f/attachment.sig>

[PATCH 3/3] ARM: mx5: Set the DBGEN bit in ARM_GPC register

[Sebastian Reichel]

Hi,

On Mon, Jun 18, 2018 at 10:52:19AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam@nxp.com>
> 
> On i.MX51/i.MX53 it is necessery to set the DBGEN bit in 
> ARM_GPC register in order to turn on the debug clocks.
> 
> The DBGEN bit of ARM_GPC register has the following description
> in the i.MX53 Reference Manual:
> 
> "This allows the user to manually activate clocks within the debug
> system. This register bit directly controls the platform's dbgen_out
> output signal which connects to the DAP_SYS to enable all debug clocks.
> Once enabled, the clocks cannot be disabled except by asserting the
> disable_trace input of the DAP_SYS."
> 
> Based on a previous patch from Sebastian Reichel.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
> ---

Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

-- Sebastian

>  arch/arm/mach-imx/common.h     |  1 +
>  arch/arm/mach-imx/cpu-imx5.c   | 38 ++++++++++++++++++++++++++++++++++++++
>  arch/arm/mach-imx/mach-imx53.c |  2 ++
>  3 files changed, 41 insertions(+)
> 
> diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
> index c8d68e9..db78329 100644
> --- a/arch/arm/mach-imx/common.h
> +++ b/arch/arm/mach-imx/common.h
> @@ -62,6 +62,7 @@ void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw);
>  void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw);
>  void imx25_pm_init(void);
>  void imx27_pm_init(void);
> +void imx5_pmu_init(void);
>  
>  enum mxc_cpu_pwr_mode {
>  	WAIT_CLOCKED,		/* wfi only */
> diff --git a/arch/arm/mach-imx/cpu-imx5.c b/arch/arm/mach-imx/cpu-imx5.c
> index 4f2d1c7..6c5a055 100644
> --- a/arch/arm/mach-imx/cpu-imx5.c
> +++ b/arch/arm/mach-imx/cpu-imx5.c
> @@ -117,3 +117,41 @@ int mx53_revision(void)
>  	return mx5_cpu_rev;
>  }
>  EXPORT_SYMBOL(mx53_revision);
> +
> +#define ARM_GPC		0x4
> +#define DBGEN		BIT(16)
> +
> +/*
> + * This enables the DBGEN bit in ARM_GPC register, which is
> + * required for accessing some performance counter features.
> + * Technically it is only required while perf is used, but to
> + * keep the source code simple we just enable it all the time
> + * when the kernel configuration allows using the feature.
> + */
> +void imx5_pmu_init(void)
> +{
> +	void __iomem *arm_plat_base;
> +	struct device_node *np;
> +	u32 gpc;
> +
> +	if (!IS_ENABLED(CONFIG_ARM_PMU))
> +		return;
> +
> +	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a8-pmu");
> +	if (!np)
> +		return;
> +
> +	np = of_find_compatible_node(NULL, NULL, "fsl,imx51-arm-plat");
> +	if (!np)
> +		return;
> +
> +	arm_plat_base = of_iomap(np, 0);
> +	if (!arm_plat_base) {
> +		pr_warn("Unable to map ARM platform registers\n");
> +		return;
> +	}
> +
> +	gpc = readl_relaxed(arm_plat_base + ARM_GPC);
> +	gpc |= DBGEN;
> +	writel_relaxed(gpc, arm_plat_base + ARM_GPC);
> +}
> diff --git a/arch/arm/mach-imx/mach-imx53.c b/arch/arm/mach-imx/mach-imx53.c
> index 07c2e8d..15fba89 100644
> --- a/arch/arm/mach-imx/mach-imx53.c
> +++ b/arch/arm/mach-imx/mach-imx53.c
> @@ -32,6 +32,8 @@ static void __init imx53_dt_init(void)
>  {
>  	imx_src_init();
>  
> +	imx5_pmu_init();
> +
>  	imx_aips_allow_unprivileged_access("fsl,imx53-aipstz");
>  }
>  
> -- 
> 2.7.4
> 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20180619/956e0d5d/attachment-0001.sig>

[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[Shawn Guo]

On Mon, Jun 18, 2018 at 10:52:17AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam@nxp.com>
> 
> As per the i.MX53 Reference Manual add an entry for the
> 'ARM platform' region in the device tree.
> 
> This is needed for accessing the ARM_GPC register to set the
> DBGEN bit, so that the debug clocks can be turned on.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
> ---
>  arch/arm/boot/dts/imx53.dtsi | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
> index 1a7a7bb..a70fbf4 100644
> --- a/arch/arm/boot/dts/imx53.dtsi
> +++ b/arch/arm/boot/dts/imx53.dtsi
> @@ -672,6 +672,11 @@
>  				status = "disabled";
>  			};
>  
> +			arm_platform: arm-platform at 63fa0000 {
> +				compatible = "fsl,imx53-arm-plat", "fsl,imx51-arm-plat";

Don't we need a bindings for that?

Shawn

> +				reg = <0x63fa0000 0x28>;
> +			};
> +
>  			owire: owire at 63fa4000 {
>  				compatible = "fsl,imx53-owire", "fsl,imx21-owire";
>  				reg = <0x63fa4000 0x4000>;
> -- 
> 2.7.4
> 

[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[Fabio Estevam]

On Wed, Jun 27, 2018 at 10:35 PM, Shawn Guo <shawnguo@kernel.org> wrote:

>> diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
>> index 1a7a7bb..a70fbf4 100644
>> --- a/arch/arm/boot/dts/imx53.dtsi
>> +++ b/arch/arm/boot/dts/imx53.dtsi
>> @@ -672,6 +672,11 @@
>>                               status = "disabled";
>>                       };
>>
>> +                     arm_platform: arm-platform at 63fa0000 {
>> +                             compatible = "fsl,imx53-arm-plat", "fsl,imx51-arm-plat";
>
> Don't we need a bindings for that?

I thought this is the same case as "fsl,imx51-src" where we only use
it inside arch/arm/mach-imx/ and there is also no bindings doc for it.

That's why I did not add an entry for the bindings doc.

If you think that a binding doc is needed, in which directory should
it be placed?

[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[Shawn Guo]

On Thu, Jun 28, 2018 at 12:02:10AM -0300, Fabio Estevam wrote:
> On Wed, Jun 27, 2018 at 10:35 PM, Shawn Guo <shawnguo@kernel.org> wrote:
> 
> >> diff --git a/arch/arm/boot/dts/imx53.dtsi b/arch/arm/boot/dts/imx53.dtsi
> >> index 1a7a7bb..a70fbf4 100644
> >> --- a/arch/arm/boot/dts/imx53.dtsi
> >> +++ b/arch/arm/boot/dts/imx53.dtsi
> >> @@ -672,6 +672,11 @@
> >>                               status = "disabled";
> >>                       };
> >>
> >> +                     arm_platform: arm-platform at 63fa0000 {
> >> +                             compatible = "fsl,imx53-arm-plat", "fsl,imx51-arm-plat";
> >
> > Don't we need a bindings for that?
> 
> I thought this is the same case as "fsl,imx51-src" where we only use
> it inside arch/arm/mach-imx/ and there is also no bindings doc for it.

Isn't 'ARM platform' something ARM core specific rather than i.MX?

> 
> That's why I did not add an entry for the bindings doc.
> 
> If you think that a binding doc is needed, in which directory should
> it be placed?

We can ask suggestion from DT folks.

Shawn

[PATCH 1/3] ARM: dts: imx53: Add 'ARM platform' node

[Fabio Estevam]

Hi Shawn,

On Thu, Jun 28, 2018 at 12:21 AM, Shawn Guo <shawnguo@kernel.org> wrote:

> Isn't 'ARM platform' something ARM core specific rather than i.MX?

i.MX51 Reference Manual names this region as 'tigerp', so I sent a v2
referring to this term and also added dt-bindings.