* [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree
@ 2017-11-14 12:20 Eugeniy Paltsev
2017-11-14 17:01 ` Vladimir Zapolskiy
0 siblings, 1 reply; 5+ messages in thread
From: Eugeniy Paltsev @ 2017-11-14 12:20 UTC (permalink / raw)
To: linux-clk
Cc: linux-kernel, linux-snps-arc, Michael Turquette, Stephen Boyd,
Rob Herring, Mark Rutland, Eugeniy Paltsev
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:
--
2.9.3
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree
2017-11-14 12:20 [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree Eugeniy Paltsev
@ 2017-11-14 17:01 ` Vladimir Zapolskiy
2017-11-14 21:19 ` Alexey Brodkin
0 siblings, 1 reply; 5+ messages in thread
From: Vladimir Zapolskiy @ 2017-11-14 17:01 UTC (permalink / raw)
To: Eugeniy Paltsev, linux-clk
Cc: linux-kernel, linux-snps-arc, Michael Turquette, Stephen Boyd,
Rob Herring, Mark Rutland
On 11/14/2017 02:20 PM, 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>;
> };
You may check Documentation/devicetree/bindings/clock/clock-bindings.txt
about how to assign initial clock rates, in general 'clock-frequency'
property is a property of clock consumers with two exceptions of simple
clock sources, namely it is used in fixed clock and PWM clock bindings.
--
With best wishes,
Vladimir
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree
2017-11-14 17:01 ` Vladimir Zapolskiy
@ 2017-11-14 21:19 ` Alexey Brodkin
2017-11-14 23:46 ` sboyd
0 siblings, 1 reply; 5+ messages in thread
From: Alexey Brodkin @ 2017-11-14 21:19 UTC (permalink / raw)
To: vladimir_zapolskiy
Cc: linux-kernel, robh+dt, mturquette, Eugeniy.Paltsev,
linux-snps-arc, mark.rutland, linux-clk, sboyd
Hi Vladimir,
On Tue, 2017-11-14 at 19:01 +0200, Vladimir Zapolskiy wrote:
> On 11/14/2017 02:20 PM, 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://urldefense.proofpoint.com/v2/url?u=https-3A__www.mail-2Darchive.com_linux-2Dsnps-2Darc-40lists.infradead.org_msg02689.html&d=DwICAg&c=DPL6
> > _X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=vTFoSv1E8NyQC8nqe6pwvuTDxGvEefhAdGwAoABOrY4&s=sbmMnczdKP317bN973cZn2WcYF29kVMLW
> > chYfhSGT2M&e=
> >
> > 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>;
> > };
>
> You may check Documentation/devicetree/bindings/clock/clock-bindings.txt
> about how to assign initial clock rates, in general 'clock-frequency'
> property is a property of clock consumers with two exceptions of simple
> clock sources, namely it is used in fixed clock and PWM clock bindings.
I think that's what we agreed on with Rob Herring back in the day.
Have you checked this post of him on the topic?
http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002909.html
Just FYI it all started from my question here:
http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002900.html
-Alexey
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree
2017-11-14 21:19 ` Alexey Brodkin
@ 2017-11-14 23:46 ` sboyd
2017-12-09 13:50 ` Eugeniy Paltsev
0 siblings, 1 reply; 5+ messages in thread
From: sboyd @ 2017-11-14 23:46 UTC (permalink / raw)
To: Alexey Brodkin
Cc: vladimir_zapolskiy, linux-kernel, robh+dt, mturquette,
Eugeniy.Paltsev, linux-snps-arc, mark.rutland, linux-clk
On 11/14, Alexey Brodkin wrote:
> Hi Vladimir,
>
> On Tue, 2017-11-14 at 19:01 +0200, Vladimir Zapolskiy wrote:
> > On 11/14/2017 02:20 PM, 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://urldefense.proofpoint.com/v2/url?u=https-3A__www.mail-2Darchive.com_linux-2Dsnps-2Darc-40lists.infradead.org_msg02689.html&d=DwICAg&c=DPL6
> > > _X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=vTFoSv1E8NyQC8nqe6pwvuTDxGvEefhAdGwAoABOrY4&s=sbmMnczdKP317bN973cZn2WcYF29kVMLW
> > > chYfhSGT2M&e=
> > >
> > > 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>;
> > > };
> >
> > You may check Documentation/devicetree/bindings/clock/clock-bindings.txt
> > about how to assign initial clock rates, in general 'clock-frequency'
> > property is a property of clock consumers with two exceptions of simple
> > clock sources, namely it is used in fixed clock and PWM clock bindings.
>
> I think that's what we agreed on with Rob Herring back in the day.
> Have you checked this post of him on the topic?
> http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002909.html
>
> Just FYI it all started from my question here:
> http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002900.html
Why can't we use assigned-clock-rates? That would basically call
clk_set_rate() on the clk once it's added.
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree
2017-11-14 23:46 ` sboyd
@ 2017-12-09 13:50 ` Eugeniy Paltsev
0 siblings, 0 replies; 5+ messages in thread
From: Eugeniy Paltsev @ 2017-12-09 13:50 UTC (permalink / raw)
To: sboyd, Alexey.Brodkin
Cc: linux-kernel, robh+dt, mturquette, Eugeniy.Paltsev,
linux-snps-arc, mark.rutland, vladimir_zapolskiy, linux-clk
On Tue, 2017-11-14 at 15:46 -0800, sboyd@codeaurora.org wrote:
> On 11/14, Alexey Brodkin wrote:
> > Hi Vladimir,
> >
> > On Tue, 2017-11-14 at 19:01 +0200, Vladimir Zapolskiy wrote:
> > > On 11/14/2017 02:20 PM, 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://urldefense.proofpoint.com/v2/url?u=https-3A__www.mail-2Darchive.com_linux-2Dsnps-2Darc-40lists.infradead.org_msg02689.html&d=DwICAg&c=
> > > > DPL6
> > > > _X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=vTFoSv1E8NyQC8nqe6pwvuTDxGvEefhAdGwAoABOrY4&s=sbmMnczdKP317bN973cZn2WcYF29k
> > > > VMLW
> > > > chYfhSGT2M&e=
> > > >
> > > > 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>;
> > > > };
> > >
> > > You may check Documentation/devicetree/bindings/clock/clock-bindings.txt
> > > about how to assign initial clock rates, in general 'clock-frequency'
> > > property is a property of clock consumers with two exceptions of simple
> > > clock sources, namely it is used in fixed clock and PWM clock bindings.
> >
> > I think that's what we agreed on with Rob Herring back in the day.
> > Have you checked this post of him on the topic?
> > https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.infradead.org_pipermail_linux-2Dsnps-2Darc_2017-2DSeptember_002909.html&d=DwIDAw&c=DPL6_
> > X_6JkXFx7AXWqB0tg&r=ZlJN1MriPUTkBKCrPSx67GmaplEUGcAEk9yPtCLdUXI&m=X0W8p5fOjiyVhK1216Lktb5yH3ojTSZhdnQhEiIVj0k&s=yGJfHbjH2T75YeIJLB14_iDjfsKi1E5aaX
> > Yu3QJBUIk&e=
> >
> > Just FYI it all started from my question here:
> > https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.infradead.org_pipermail_linux-2Dsnps-2Darc_2017-2DSeptember_002900.html&d=DwIDAw&c=DPL6_
> > X_6JkXFx7AXWqB0tg&r=ZlJN1MriPUTkBKCrPSx67GmaplEUGcAEk9yPtCLdUXI&m=X0W8p5fOjiyVhK1216Lktb5yH3ojTSZhdnQhEiIVj0k&s=Jkzt2G_J4aE9JfePPQ57ldnrFWeS57Rhfc
> > Mhun92oU0&e=
>
> Why can't we use assigned-clock-rates? That would basically call
> clk_set_rate() on the clk once it's added.
Thanks for the hint, assigned-clock-rates works for us.
--
Eugeniy Paltsev
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2017-12-09 13:50 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-11-14 12:20 [PATCH RESEND] CLK: ARC: Set initial pll output frequency specified in device tree Eugeniy Paltsev
2017-11-14 17:01 ` Vladimir Zapolskiy
2017-11-14 21:19 ` Alexey Brodkin
2017-11-14 23:46 ` sboyd
2017-12-09 13:50 ` Eugeniy Paltsev
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).