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 at lists.infradead.org/msg02689.html > > Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at 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
