CLK: ARC: Set initial pll output frequency specified in device tree

Message ID 20170929131357.26796-1-Eugeniy.Paltsev@synopsys.com
State New
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Series
  • CLK: ARC: Set initial pll output frequency specified in device tree
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Commit Message

Eugeniy Paltsev Sept. 29, 2017, 1:13 p.m.
Add option to set initial output frequency of plls via
"clock-frequency" property in pll's device tree node.
This frequency will be set while pll driver probed.

The usage example is setting CPU clock frequency on boot
See discussion:
https://www.mail-archive.com/linux-snps-arc@lists.infradead.org/msg02689.html

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
 .../bindings/clock/snps,hsdk-pll-clock.txt         |  5 ++++
 .../devicetree/bindings/clock/snps,pll-clock.txt   |  5 ++++
 drivers/clk/axs10x/pll_clock.c                     | 34 ++++++++++++++++++++--
 drivers/clk/clk-hsdk-pll.c                         | 34 ++++++++++++++++++++--
 4 files changed, 74 insertions(+), 4 deletions(-)

Comments

Vineet Gupta Oct. 26, 2017, 6:25 p.m. | #1
Hi folks,


On 09/29/2017 06:13 AM, Eugeniy Paltsev wrote:
> Add option to set initial output frequency of plls via
> "clock-frequency" property in pll's device tree node.
> This frequency will be set while pll driver probed.
> 
> The usage example is setting CPU clock frequency on boot
> See discussion:
> https://www.mail-archive.com/linux-snps-arc@lists.infradead.org/msg02689.html

Any yay / nay on this please ?

I guess some de-duplication is in order anyways but is the overall approach sane ?

Additional background / context in thread
http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002900.html

Thx,
-Vineet



> 
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
> ---
>   .../bindings/clock/snps,hsdk-pll-clock.txt         |  5 ++++
>   .../devicetree/bindings/clock/snps,pll-clock.txt   |  5 ++++
>   drivers/clk/axs10x/pll_clock.c                     | 34 ++++++++++++++++++++--
>   drivers/clk/clk-hsdk-pll.c                         | 34 ++++++++++++++++++++--
>   4 files changed, 74 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt b/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt
> index c56c755..5703059 100644
> --- a/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt
> +++ b/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt
> @@ -13,6 +13,10 @@ Required properties:
>   - clocks: shall be the input parent clock phandle for the PLL.
>   - #clock-cells: from common clock binding; Should always be set to 0.
>   
> +Optional properties:
> +- clock-frequency: output frequency generated by pll in Hz which will be set
> +while probing. Should be a single cell.
> +
>   Example:
>   	input_clk: input-clk {
>   		clock-frequency = <33333333>;
> @@ -25,4 +29,5 @@ Example:
>   		reg = <0x00 0x10>;
>   		#clock-cells = <0>;
>   		clocks = <&input_clk>;
> +		clock-frequency = <1000000000>;
>   	};
> diff --git a/Documentation/devicetree/bindings/clock/snps,pll-clock.txt b/Documentation/devicetree/bindings/clock/snps,pll-clock.txt
> index 11fe487..5908f99 100644
> --- a/Documentation/devicetree/bindings/clock/snps,pll-clock.txt
> +++ b/Documentation/devicetree/bindings/clock/snps,pll-clock.txt
> @@ -13,6 +13,10 @@ registers and second for corresponding LOCK CGU register.
>   - clocks: shall be the input parent clock phandle for the PLL.
>   - #clock-cells: from common clock binding; Should always be set to 0.
>   
> +Optional properties:
> +- clock-frequency: output frequency generated by pll in Hz which will be set
> +while probing. Should be a single cell.
> +
>   Example:
>   	input-clk: input-clk {
>   		clock-frequency = <33333333>;
> @@ -25,4 +29,5 @@ Example:
>   		reg = <0x80 0x10>, <0x100 0x10>;
>   		#clock-cells = <0>;
>   		clocks = <&input-clk>;
> +		clock-frequency = <100000000>;
>   	};
> diff --git a/drivers/clk/axs10x/pll_clock.c b/drivers/clk/axs10x/pll_clock.c
> index 25d8c24..3f4345d 100644
> --- a/drivers/clk/axs10x/pll_clock.c
> +++ b/drivers/clk/axs10x/pll_clock.c
> @@ -11,6 +11,7 @@
>   #include <linux/platform_device.h>
>   #include <linux/module.h>
>   #include <linux/clk-provider.h>
> +#include <linux/clk.h>
>   #include <linux/delay.h>
>   #include <linux/err.h>
>   #include <linux/device.h>
> @@ -215,6 +216,25 @@ static const struct clk_ops axs10x_pll_ops = {
>   	.set_rate = axs10x_pll_set_rate,
>   };
>   
> +static void set_pll_rate_from_of(struct clk *clk, struct device_node *node)
> +{
> +	u32 requested_rate;
> +
> +	/* If we specify initial pll output frequency try to set it */
> +	if (of_property_read_u32(node, "clock-frequency", &requested_rate))
> +		return;
> +
> +	if (clk_prepare_enable(clk)) {
> +		pr_err("Cannot enable %s clock.\n", node->name);
> +		return;
> +	}
> +
> +	if (clk_set_rate(clk, requested_rate))
> +		pr_err("Cannot set %s clock rate.\n", node->name);
> +
> +	pr_debug("Set %s clock to %u\n", node->name, requested_rate);
> +}
> +
>   static int axs10x_pll_clk_probe(struct platform_device *pdev)
>   {
>   	struct device *dev = &pdev->dev;
> @@ -258,8 +278,15 @@ static int axs10x_pll_clk_probe(struct platform_device *pdev)
>   		return ret;
>   	}
>   
> -	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
> -			&pll_clk->hw);
> +	ret =  of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
> +				      &pll_clk->hw);
> +	if (ret)
> +		return ret;
> +
> +	/* If we specify initial pll output frequency in dts try to set it */
> +	set_pll_rate_from_of(pll_clk->hw.clk, dev->of_node);
> +
> +	return 0;
>   }
>   
>   static int axs10x_pll_clk_remove(struct platform_device *pdev)
> @@ -311,6 +338,9 @@ static void __init of_axs10x_pll_clk_setup(struct device_node *node)
>   		goto err_unregister_clk;
>   	}
>   
> +	/* If we specify initial pll output frequency in dts try to set it */
> +	set_pll_rate_from_of(pll_clk->hw.clk, node);
> +
>   	return;
>   
>   err_unregister_clk:
> diff --git a/drivers/clk/clk-hsdk-pll.c b/drivers/clk/clk-hsdk-pll.c
> index bbf23717..74fd006 100644
> --- a/drivers/clk/clk-hsdk-pll.c
> +++ b/drivers/clk/clk-hsdk-pll.c
> @@ -9,6 +9,7 @@
>    */
>   
>   #include <linux/clk-provider.h>
> +#include <linux/clk.h>
>   #include <linux/delay.h>
>   #include <linux/device.h>
>   #include <linux/err.h>
> @@ -295,6 +296,25 @@ static const struct clk_ops hsdk_pll_ops = {
>   	.set_rate = hsdk_pll_set_rate,
>   };
>   
> +static void set_pll_rate_from_of(struct clk *clk, struct device_node *node)
> +{
> +	u32 requested_rate;
> +
> +	/* If we specify initial pll output frequency try to set it */
> +	if (of_property_read_u32(node, "clock-frequency", &requested_rate))
> +		return;
> +
> +	if (clk_prepare_enable(clk)) {
> +		pr_err("Cannot enable %s clock.\n", node->name);
> +		return;
> +	}
> +
> +	if (clk_set_rate(clk, requested_rate))
> +		pr_err("Cannot set %s clock rate.\n", node->name);
> +
> +	pr_debug("Set %s clock to %u\n", node->name, requested_rate);
> +}
> +
>   static int hsdk_pll_clk_probe(struct platform_device *pdev)
>   {
>   	int ret;
> @@ -340,8 +360,15 @@ static int hsdk_pll_clk_probe(struct platform_device *pdev)
>   		return ret;
>   	}
>   
> -	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
> -			&pll_clk->hw);
> +	ret =  of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
> +				      &pll_clk->hw);
> +	if (ret)
> +		return ret;
> +
> +	/* If we specify initial pll output frequency in dts try to set it */
> +	set_pll_rate_from_of(pll_clk->hw.clk, dev->of_node);
> +
> +	return 0;
>   }
>   
>   static int hsdk_pll_clk_remove(struct platform_device *pdev)
> @@ -400,6 +427,9 @@ static void __init of_hsdk_pll_clk_setup(struct device_node *node)
>   		goto err_unmap_spec_regs;
>   	}
>   
> +	/* If we specify initial pll output frequency in dts try to set it */
> +	set_pll_rate_from_of(pll_clk->hw.clk, node);
> +
>   	return;
>   
>   err_unmap_spec_regs:
>
Eugeniy Paltsev Nov. 13, 2017, 3:35 p.m. | #2
Hi Stephen, Michael,

Please treat this message as a polite reminder to review my patch.
It would be really nice to see this patch in 4.15.

Thanks.

On Fri, 2017-09-29 at 16:13 +0300, Eugeniy Paltsev wrote:
> Add option to set initial output frequency of plls via

> "clock-frequency" property in pll's device tree node.

> This frequency will be set while pll driver probed.

> 

> The usage example is setting CPU clock frequency on boot

> See discussion:

> https://www.mail-archive.com/linux-snps-arc@lists.infradead.org/msg02689.html

> 

> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>

> ---

>  .../bindings/clock/snps,hsdk-pll-clock.txt         |  5 ++++

>  .../devicetree/bindings/clock/snps,pll-clock.txt   |  5 ++++

>  drivers/clk/axs10x/pll_clock.c                     | 34 ++++++++++++++++++++--

>  drivers/clk/clk-hsdk-pll.c                         | 34 ++++++++++++++++++++--

>  4 files changed, 74 insertions(+), 4 deletions(-)

> 

> diff --git a/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt b/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt

> index c56c755..5703059 100644

> --- a/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt

> +++ b/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt

> @@ -13,6 +13,10 @@ Required properties:

>  - clocks: shall be the input parent clock phandle for the PLL.

>  - #clock-cells: from common clock binding; Should always be set to 0.

>  

> +Optional properties:

> +- clock-frequency: output frequency generated by pll in Hz which will be set

> +while probing. Should be a single cell.

> +

>  Example:

>  	input_clk: input-clk {

>  		clock-frequency = <33333333>;

> @@ -25,4 +29,5 @@ Example:

>  		reg = <0x00 0x10>;

>  		#clock-cells = <0>;

>  		clocks = <&input_clk>;

> +		clock-frequency = <1000000000>;

>  	};

> diff --git a/Documentation/devicetree/bindings/clock/snps,pll-clock.txt b/Documentation/devicetree/bindings/clock/snps,pll-clock.txt

> index 11fe487..5908f99 100644

> --- a/Documentation/devicetree/bindings/clock/snps,pll-clock.txt

> +++ b/Documentation/devicetree/bindings/clock/snps,pll-clock.txt

> @@ -13,6 +13,10 @@ registers and second for corresponding LOCK CGU register.

>  - clocks: shall be the input parent clock phandle for the PLL.

>  - #clock-cells: from common clock binding; Should always be set to 0.

>  

> +Optional properties:

> +- clock-frequency: output frequency generated by pll in Hz which will be set

> +while probing. Should be a single cell.

> +

>  Example:

>  	input-clk: input-clk {

>  		clock-frequency = <33333333>;

> @@ -25,4 +29,5 @@ Example:

>  		reg = <0x80 0x10>, <0x100 0x10>;

>  		#clock-cells = <0>;

>  		clocks = <&input-clk>;

> +		clock-frequency = <100000000>;

>  	};

> diff --git a/drivers/clk/axs10x/pll_clock.c b/drivers/clk/axs10x/pll_clock.c

> index 25d8c24..3f4345d 100644

> --- a/drivers/clk/axs10x/pll_clock.c

> +++ b/drivers/clk/axs10x/pll_clock.c

> @@ -11,6 +11,7 @@

>  #include <linux/platform_device.h>

>  #include <linux/module.h>

>  #include <linux/clk-provider.h>

> +#include <linux/clk.h>

>  #include <linux/delay.h>

>  #include <linux/err.h>

>  #include <linux/device.h>

> @@ -215,6 +216,25 @@ static const struct clk_ops axs10x_pll_ops = {

>  	.set_rate = axs10x_pll_set_rate,

>  };

>  

> +static void set_pll_rate_from_of(struct clk *clk, struct device_node *node)

> +{

> +	u32 requested_rate;

> +

> +	/* If we specify initial pll output frequency try to set it */

> +	if (of_property_read_u32(node, "clock-frequency", &requested_rate))

> +		return;

> +

> +	if (clk_prepare_enable(clk)) {

> +		pr_err("Cannot enable %s clock.\n", node->name);

> +		return;

> +	}

> +

> +	if (clk_set_rate(clk, requested_rate))

> +		pr_err("Cannot set %s clock rate.\n", node->name);

> +

> +	pr_debug("Set %s clock to %u\n", node->name, requested_rate);

> +}

> +

>  static int axs10x_pll_clk_probe(struct platform_device *pdev)

>  {

>  	struct device *dev = &pdev->dev;

> @@ -258,8 +278,15 @@ static int axs10x_pll_clk_probe(struct platform_device *pdev)

>  		return ret;

>  	}

>  

> -	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,

> -			&pll_clk->hw);

> +	ret =  of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,

> +				      &pll_clk->hw);

> +	if (ret)

> +		return ret;

> +

> +	/* If we specify initial pll output frequency in dts try to set it */

> +	set_pll_rate_from_of(pll_clk->hw.clk, dev->of_node);

> +

> +	return 0;

>  }

>  

>  static int axs10x_pll_clk_remove(struct platform_device *pdev)

> @@ -311,6 +338,9 @@ static void __init of_axs10x_pll_clk_setup(struct device_node *node)

>  		goto err_unregister_clk;

>  	}

>  

> +	/* If we specify initial pll output frequency in dts try to set it */

> +	set_pll_rate_from_of(pll_clk->hw.clk, node);

> +

>  	return;

>  

>  err_unregister_clk:

> diff --git a/drivers/clk/clk-hsdk-pll.c b/drivers/clk/clk-hsdk-pll.c

> index bbf23717..74fd006 100644

> --- a/drivers/clk/clk-hsdk-pll.c

> +++ b/drivers/clk/clk-hsdk-pll.c

> @@ -9,6 +9,7 @@

>   */

>  

>  #include <linux/clk-provider.h>

> +#include <linux/clk.h>

>  #include <linux/delay.h>

>  #include <linux/device.h>

>  #include <linux/err.h>

> @@ -295,6 +296,25 @@ static const struct clk_ops hsdk_pll_ops = {

>  	.set_rate = hsdk_pll_set_rate,

>  };

>  

> +static void set_pll_rate_from_of(struct clk *clk, struct device_node *node)

> +{

> +	u32 requested_rate;

> +

> +	/* If we specify initial pll output frequency try to set it */

> +	if (of_property_read_u32(node, "clock-frequency", &requested_rate))

> +		return;

> +

> +	if (clk_prepare_enable(clk)) {

> +		pr_err("Cannot enable %s clock.\n", node->name);

> +		return;

> +	}

> +

> +	if (clk_set_rate(clk, requested_rate))

> +		pr_err("Cannot set %s clock rate.\n", node->name);

> +

> +	pr_debug("Set %s clock to %u\n", node->name, requested_rate);

> +}

> +

>  static int hsdk_pll_clk_probe(struct platform_device *pdev)

>  {

>  	int ret;

> @@ -340,8 +360,15 @@ static int hsdk_pll_clk_probe(struct platform_device *pdev)

>  		return ret;

>  	}

>  

> -	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,

> -			&pll_clk->hw);

> +	ret =  of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,

> +				      &pll_clk->hw);

> +	if (ret)

> +		return ret;

> +

> +	/* If we specify initial pll output frequency in dts try to set it */

> +	set_pll_rate_from_of(pll_clk->hw.clk, dev->of_node);

> +

> +	return 0;

>  }

>  

>  static int hsdk_pll_clk_remove(struct platform_device *pdev)

> @@ -400,6 +427,9 @@ static void __init of_hsdk_pll_clk_setup(struct device_node *node)

>  		goto err_unmap_spec_regs;

>  	}

>  

> +	/* If we specify initial pll output frequency in dts try to set it */

> +	set_pll_rate_from_of(pll_clk->hw.clk, node);

> +

>  	return;

>  

>  err_unmap_spec_regs:

-- 
 Eugeniy Paltsev
Stephen Boyd Nov. 13, 2017, 10:29 p.m. | #3
On 11/13, Eugeniy Paltsev wrote:
> Hi Stephen, Michael,
> 
> Please treat this message as a polite reminder to review my patch.
> It would be really nice to see this patch in 4.15.

Sorry I don't have this in my queue. It might make v4.15 but the
mere window is open now and I lost this patch somehow so
hopefully I can throw it into the pile.

Patch

diff --git a/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt b/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt
index c56c755..5703059 100644
--- a/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt
+++ b/Documentation/devicetree/bindings/clock/snps,hsdk-pll-clock.txt
@@ -13,6 +13,10 @@  Required properties:
 - clocks: shall be the input parent clock phandle for the PLL.
 - #clock-cells: from common clock binding; Should always be set to 0.
 
+Optional properties:
+- clock-frequency: output frequency generated by pll in Hz which will be set
+while probing. Should be a single cell.
+
 Example:
 	input_clk: input-clk {
 		clock-frequency = <33333333>;
@@ -25,4 +29,5 @@  Example:
 		reg = <0x00 0x10>;
 		#clock-cells = <0>;
 		clocks = <&input_clk>;
+		clock-frequency = <1000000000>;
 	};
diff --git a/Documentation/devicetree/bindings/clock/snps,pll-clock.txt b/Documentation/devicetree/bindings/clock/snps,pll-clock.txt
index 11fe487..5908f99 100644
--- a/Documentation/devicetree/bindings/clock/snps,pll-clock.txt
+++ b/Documentation/devicetree/bindings/clock/snps,pll-clock.txt
@@ -13,6 +13,10 @@  registers and second for corresponding LOCK CGU register.
 - clocks: shall be the input parent clock phandle for the PLL.
 - #clock-cells: from common clock binding; Should always be set to 0.
 
+Optional properties:
+- clock-frequency: output frequency generated by pll in Hz which will be set
+while probing. Should be a single cell.
+
 Example:
 	input-clk: input-clk {
 		clock-frequency = <33333333>;
@@ -25,4 +29,5 @@  Example:
 		reg = <0x80 0x10>, <0x100 0x10>;
 		#clock-cells = <0>;
 		clocks = <&input-clk>;
+		clock-frequency = <100000000>;
 	};
diff --git a/drivers/clk/axs10x/pll_clock.c b/drivers/clk/axs10x/pll_clock.c
index 25d8c24..3f4345d 100644
--- a/drivers/clk/axs10x/pll_clock.c
+++ b/drivers/clk/axs10x/pll_clock.c
@@ -11,6 +11,7 @@ 
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/clk-provider.h>
+#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/device.h>
@@ -215,6 +216,25 @@  static const struct clk_ops axs10x_pll_ops = {
 	.set_rate = axs10x_pll_set_rate,
 };
 
+static void set_pll_rate_from_of(struct clk *clk, struct device_node *node)
+{
+	u32 requested_rate;
+
+	/* If we specify initial pll output frequency try to set it */
+	if (of_property_read_u32(node, "clock-frequency", &requested_rate))
+		return;
+
+	if (clk_prepare_enable(clk)) {
+		pr_err("Cannot enable %s clock.\n", node->name);
+		return;
+	}
+
+	if (clk_set_rate(clk, requested_rate))
+		pr_err("Cannot set %s clock rate.\n", node->name);
+
+	pr_debug("Set %s clock to %u\n", node->name, requested_rate);
+}
+
 static int axs10x_pll_clk_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -258,8 +278,15 @@  static int axs10x_pll_clk_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
-			&pll_clk->hw);
+	ret =  of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
+				      &pll_clk->hw);
+	if (ret)
+		return ret;
+
+	/* If we specify initial pll output frequency in dts try to set it */
+	set_pll_rate_from_of(pll_clk->hw.clk, dev->of_node);
+
+	return 0;
 }
 
 static int axs10x_pll_clk_remove(struct platform_device *pdev)
@@ -311,6 +338,9 @@  static void __init of_axs10x_pll_clk_setup(struct device_node *node)
 		goto err_unregister_clk;
 	}
 
+	/* If we specify initial pll output frequency in dts try to set it */
+	set_pll_rate_from_of(pll_clk->hw.clk, node);
+
 	return;
 
 err_unregister_clk:
diff --git a/drivers/clk/clk-hsdk-pll.c b/drivers/clk/clk-hsdk-pll.c
index bbf23717..74fd006 100644
--- a/drivers/clk/clk-hsdk-pll.c
+++ b/drivers/clk/clk-hsdk-pll.c
@@ -9,6 +9,7 @@ 
  */
 
 #include <linux/clk-provider.h>
+#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/err.h>
@@ -295,6 +296,25 @@  static const struct clk_ops hsdk_pll_ops = {
 	.set_rate = hsdk_pll_set_rate,
 };
 
+static void set_pll_rate_from_of(struct clk *clk, struct device_node *node)
+{
+	u32 requested_rate;
+
+	/* If we specify initial pll output frequency try to set it */
+	if (of_property_read_u32(node, "clock-frequency", &requested_rate))
+		return;
+
+	if (clk_prepare_enable(clk)) {
+		pr_err("Cannot enable %s clock.\n", node->name);
+		return;
+	}
+
+	if (clk_set_rate(clk, requested_rate))
+		pr_err("Cannot set %s clock rate.\n", node->name);
+
+	pr_debug("Set %s clock to %u\n", node->name, requested_rate);
+}
+
 static int hsdk_pll_clk_probe(struct platform_device *pdev)
 {
 	int ret;
@@ -340,8 +360,15 @@  static int hsdk_pll_clk_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
-			&pll_clk->hw);
+	ret =  of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
+				      &pll_clk->hw);
+	if (ret)
+		return ret;
+
+	/* If we specify initial pll output frequency in dts try to set it */
+	set_pll_rate_from_of(pll_clk->hw.clk, dev->of_node);
+
+	return 0;
 }
 
 static int hsdk_pll_clk_remove(struct platform_device *pdev)
@@ -400,6 +427,9 @@  static void __init of_hsdk_pll_clk_setup(struct device_node *node)
 		goto err_unmap_spec_regs;
 	}
 
+	/* If we specify initial pll output frequency in dts try to set it */
+	set_pll_rate_from_of(pll_clk->hw.clk, node);
+
 	return;
 
 err_unmap_spec_regs: