| Message ID | 20171114122020.9800-1-Eugeniy.Paltsev@synopsys.com |
|---|---|
| State | New |
| Headers | show |
| Series | [RESEND] CLK: ARC: Set initial pll output frequency specified in device tree | expand |
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
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
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.
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
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:
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(-)