[PATCH 1/3] dt-bindings: qoriq-clock: Add coreclk

[PATCH 1/3] dt-bindings: qoriq-clock: Add coreclk

[Scott Wood]

ls1012a has separate input root clocks for core PLLs versus the platform
PLL, with the latter described as sysclk in the hw docs.

Update the qoriq-clock binding to allow a second input clock, named
"coreclk".  If present, this clock will be used for the core PLLs.

Signed-off-by: Scott Wood <oss@buserror.net>
Cc: devicetree@vger.kernel.org
---
 Documentation/devicetree/bindings/clock/qoriq-clock.txt | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/clock/qoriq-clock.txt b/Documentation/devicetree/bindings/clock/qoriq-clock.txt
index df9cb5a..97a9666 100644
--- a/Documentation/devicetree/bindings/clock/qoriq-clock.txt
+++ b/Documentation/devicetree/bindings/clock/qoriq-clock.txt
@@ -55,6 +55,11 @@ Optional properties:
 - clocks: If clock-frequency is not specified, sysclk may be provided
 	as an input clock.  Either clock-frequency or clocks must be
 	provided.
+	A second input clock, called "coreclk", may be provided if
+	core PLLs are based on a different input clock from the
+	platform PLL.
+- clock-names: Required if a coreclk is present.  Valid names are
+	"sysclk" and "coreclk".
 
 2. Clock Provider
 
@@ -71,6 +76,7 @@ second cell is the clock index for the specified type.
 	2	hwaccel		index (n in CLKCGnHWACSR)
 	3	fman		0 for fm1, 1 for fm2
 	4	platform pll	0=pll, 1=pll/2, 2=pll/3, 3=pll/4
+	5	coreclk		must be 0
 
 3. Example
 
-- 
2.7.4

[PATCH 2/3] arm64: dts: ls1012a: Add coreclk

[Scott Wood]

ls1012a has separate input root clocks for core PLLs versus the platform
PLL, with the latter described as sysclk in the hw docs.

Signed-off-by: Scott Wood <oss@buserror.net>
---
Note that current versions of U-Boot are blindly updating the frequency
of all fixed-clock nodes.  That needs to be fixed for the split input
frequency to work properly, but until U-Boot is fixed this change doesn't
make anything worse than it already was.

 arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi b/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi
index cffebb4..515f8488 100644
--- a/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi
+++ b/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi
@@ -66,10 +66,17 @@
 	sysclk: sysclk {
 		compatible = "fixed-clock";
 		#clock-cells = <0>;
-		clock-frequency = <100000000>;
+		clock-frequency = <125000000>;
 		clock-output-names = "sysclk";
 	};
 
+	coreclk: coreclk {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <100000000>;
+		clock-output-names = "coreclk";
+	};
+
 	timer {
 		compatible = "arm,armv8-timer";
 		interrupts = <1 13 IRQ_TYPE_LEVEL_LOW>,/* Physical Secure PPI */
@@ -124,7 +131,8 @@
 			compatible = "fsl,ls1012a-clockgen";
 			reg = <0x0 0x1ee1000 0x0 0x1000>;
 			#clock-cells = <2>;
-			clocks = <&sysclk>;
+			clocks = <&sysclk &coreclk>;
+			clock-names = "sysclk", "coreclk";
 		};
 
 		i2c0: i2c@2180000 {
-- 
2.7.4

Re: [PATCH 2/3] arm64: dts: ls1012a: Add coreclk

[Shawn Guo]

On Wed, Jan 25, 2017 at 02:19:22AM -0600, Scott Wood wrote:
> ls1012a has separate input root clocks for core PLLs versus the platform
> PLL, with the latter described as sysclk in the hw docs.
> 
> Signed-off-by: Scott Wood <oss@buserror.net>
> ---
> Note that current versions of U-Boot are blindly updating the frequency
> of all fixed-clock nodes.  That needs to be fixed for the split input
> frequency to work properly, but until U-Boot is fixed this change doesn't
> make anything worse than it already was.
> 
>  arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi b/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi
> index cffebb4..515f8488 100644
> --- a/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi
> +++ b/arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi
> @@ -66,10 +66,17 @@
>  	sysclk: sysclk {
>  		compatible = "fixed-clock";
>  		#clock-cells = <0>;
> -		clock-frequency = <100000000>;
> +		clock-frequency = <125000000>;

Should we mention this change a bit in the commit log?

Shawn

>  		clock-output-names = "sysclk";
>  	};
>  
> +	coreclk: coreclk {
> +		compatible = "fixed-clock";
> +		#clock-cells = <0>;
> +		clock-frequency = <100000000>;
> +		clock-output-names = "coreclk";
> +	};
> +
>  	timer {
>  		compatible = "arm,armv8-timer";
>  		interrupts = <1 13 IRQ_TYPE_LEVEL_LOW>,/* Physical Secure PPI */
> @@ -124,7 +131,8 @@
>  			compatible = "fsl,ls1012a-clockgen";
>  			reg = <0x0 0x1ee1000 0x0 0x1000>;
>  			#clock-cells = <2>;
> -			clocks = <&sysclk>;
> +			clocks = <&sysclk &coreclk>;
> +			clock-names = "sysclk", "coreclk";
>  		};
>  
>  		i2c0: i2c@2180000 {
> -- 
> 2.7.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 3/3] clk: qoriq: Separate root input clock for core PLLs on ls1012a

[Scott Wood]

ls1012a has separate input root clocks for core PLLs versus the
platform PLL, with the latter described as sysclk in the hw docs.

If a second input clock, named "coreclk", is present, this clock will be
used for the core PLLs.

Signed-off-by: Scott Wood <oss@buserror.net>
---
 drivers/clk/clk-qoriq.c | 91 +++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 77 insertions(+), 14 deletions(-)

diff --git a/drivers/clk/clk-qoriq.c b/drivers/clk/clk-qoriq.c
index d0bf8b1..f3931e3 100644
--- a/drivers/clk/clk-qoriq.c
+++ b/drivers/clk/clk-qoriq.c
@@ -87,7 +87,7 @@ struct clockgen {
 	struct device_node *node;
 	void __iomem *regs;
 	struct clockgen_chipinfo info; /* mutable copy */
-	struct clk *sysclk;
+	struct clk *sysclk, *coreclk;
 	struct clockgen_pll pll[6];
 	struct clk *cmux[NUM_CMUX];
 	struct clk *hwaccel[NUM_HWACCEL];
@@ -904,7 +904,12 @@ static void __init create_muxes(struct clockgen *cg)
 
 static void __init clockgen_init(struct device_node *np);
 
-/* Legacy nodes may get probed before the parent clockgen node */
+/*
+ * Legacy nodes may get probed before the parent clockgen node.
+ * It is assumed that device trees with legacy nodes will not
+ * contain a "clocks" property -- otherwise the input clocks may
+ * not be initialized at this point.
+ */
 static void __init legacy_init_clockgen(struct device_node *np)
 {
 	if (!clockgen.node)
@@ -945,18 +950,13 @@ static struct clk __init
 	return clk_register_fixed_rate(NULL, name, NULL, 0, rate);
 }
 
-static struct clk *sysclk_from_parent(const char *name)
+static struct clk __init *input_clock(const char *name, struct clk *clk)
 {
-	struct clk *clk;
-	const char *parent_name;
-
-	clk = of_clk_get(clockgen.node, 0);
-	if (IS_ERR(clk))
-		return clk;
+	const char *input_name;
 
 	/* Register the input clock under the desired name. */
-	parent_name = __clk_get_name(clk);
-	clk = clk_register_fixed_factor(NULL, name, parent_name,
+	input_name = __clk_get_name(clk);
+	clk = clk_register_fixed_factor(NULL, name, input_name,
 					0, 1, 1);
 	if (IS_ERR(clk))
 		pr_err("%s: Couldn't register %s: %ld\n", __func__, name,
@@ -965,6 +965,29 @@ static struct clk *sysclk_from_parent(const char *name)
 	return clk;
 }
 
+static struct clk __init *input_clock_by_name(const char *name,
+					      const char *dtname)
+{
+	struct clk *clk;
+
+	clk = of_clk_get_by_name(clockgen.node, dtname);
+	if (IS_ERR(clk))
+		return clk;
+
+	return input_clock(name, clk);
+}
+
+static struct clk __init *input_clock_by_index(const char *name, int idx)
+{
+	struct clk *clk;
+
+	clk = of_clk_get(clockgen.node, 0);
+	if (IS_ERR(clk))
+		return clk;
+
+	return input_clock(name, clk);
+}
+
 static struct clk * __init create_sysclk(const char *name)
 {
 	struct device_node *sysclk;
@@ -974,7 +997,11 @@ static struct clk * __init create_sysclk(const char *name)
 	if (!IS_ERR(clk))
 		return clk;
 
-	clk = sysclk_from_parent(name);
+	clk = input_clock_by_name(name, "sysclk");
+	if (!IS_ERR(clk))
+		return clk;
+
+	clk = input_clock_by_index(name, 0);
 	if (!IS_ERR(clk))
 		return clk;
 
@@ -985,7 +1012,27 @@ static struct clk * __init create_sysclk(const char *name)
 			return clk;
 	}
 
-	pr_err("%s: No input clock\n", __func__);
+	pr_err("%s: No input sysclk\n", __func__);
+	return NULL;
+}
+
+static struct clk * __init create_coreclk(const char *name)
+{
+	struct clk *clk;
+
+	clk = input_clock_by_name(name, "coreclk");
+	if (!IS_ERR(clk))
+		return clk;
+
+	/*
+	 * This indicates a mix of legacy nodes with the new coreclk
+	 * mechanism, which should never happen.  If this error occurs,
+	 * don't use the wrong input clock just because coreclk isn't
+	 * ready yet.
+	 */
+	if (WARN_ON(PTR_ERR(clk) == -EPROBE_DEFER))
+		return clk;
+
 	return NULL;
 }
 
@@ -1008,11 +1055,19 @@ static void __init create_one_pll(struct clockgen *cg, int idx)
 	u32 __iomem *reg;
 	u32 mult;
 	struct clockgen_pll *pll = &cg->pll[idx];
+	const char *input = "cg-sysclk";
 	int i;
 
 	if (!(cg->info.pll_mask & (1 << idx)))
 		return;
 
+	if (cg->coreclk && idx != PLATFORM_PLL) {
+		if (IS_ERR(cg->coreclk))
+			return;
+
+		input = "cg-coreclk";
+	}
+
 	if (cg->info.flags & CG_VER3) {
 		switch (idx) {
 		case PLATFORM_PLL:
@@ -1063,7 +1118,7 @@ static void __init create_one_pll(struct clockgen *cg, int idx)
 			 "cg-pll%d-div%d", idx, i + 1);
 
 		clk = clk_register_fixed_factor(NULL,
-				pll->div[i].name, "cg-sysclk", 0, mult, i + 1);
+				pll->div[i].name, input, 0, mult, i + 1);
 		if (IS_ERR(clk)) {
 			pr_err("%s: %s: register failed %ld\n",
 			       __func__, pll->div[i].name, PTR_ERR(clk));
@@ -1200,6 +1255,13 @@ static struct clk *clockgen_clk_get(struct of_phandle_args *clkspec, void *data)
 			goto bad_args;
 		clk = pll->div[idx].clk;
 		break;
+	case 5:
+		if (idx != 0)
+			goto bad_args;
+		clk = cg->coreclk;
+		if (IS_ERR(clk))
+			clk = NULL;
+		break;
 	default:
 		goto bad_args;
 	}
@@ -1311,6 +1373,7 @@ static void __init clockgen_init(struct device_node *np)
 		clockgen.info.flags |= CG_CMUX_GE_PLAT;
 
 	clockgen.sysclk = create_sysclk("cg-sysclk");
+	clockgen.coreclk = create_coreclk("cg-coreclk");
 	create_plls(&clockgen);
 	create_muxes(&clockgen);
 
-- 
2.7.4

Re: [PATCH 1/3] dt-bindings: qoriq-clock: Add coreclk

[Rob Herring]

On Wed, Jan 25, 2017 at 02:19:21AM -0600, Scott Wood wrote:
> ls1012a has separate input root clocks for core PLLs versus the platform
> PLL, with the latter described as sysclk in the hw docs.
> 
> Update the qoriq-clock binding to allow a second input clock, named
> "coreclk".  If present, this clock will be used for the core PLLs.
> 
> Signed-off-by: Scott Wood <oss@buserror.net>
> Cc: devicetree@vger.kernel.org
> ---
>  Documentation/devicetree/bindings/clock/qoriq-clock.txt | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/clock/qoriq-clock.txt b/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> index df9cb5a..97a9666 100644
> --- a/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> +++ b/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> @@ -55,6 +55,11 @@ Optional properties:
>  - clocks: If clock-frequency is not specified, sysclk may be provided
>  	as an input clock.  Either clock-frequency or clocks must be
>  	provided.
> +	A second input clock, called "coreclk", may be provided if
> +	core PLLs are based on a different input clock from the
> +	platform PLL.
> +- clock-names: Required if a coreclk is present.  Valid names are
> +	"sysclk" and "coreclk".

'clk' part is redundant.

>  
>  2. Clock Provider
>  
> @@ -71,6 +76,7 @@ second cell is the clock index for the specified type.
>  	2	hwaccel		index (n in CLKCGnHWACSR)
>  	3	fman		0 for fm1, 1 for fm2
>  	4	platform pll	0=pll, 1=pll/2, 2=pll/3, 3=pll/4
> +	5	coreclk		must be 0
>  
>  3. Example
>  
> -- 
> 2.7.4
> 
> --
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Re: [PATCH 1/3] dt-bindings: qoriq-clock: Add coreclk

[Scott Wood]

On Fri, 2017-01-27 at 16:38 -0600, Rob Herring wrote:
> On Wed, Jan 25, 2017 at 02:19:21AM -0600, Scott Wood wrote:
> > 
> > ls1012a has separate input root clocks for core PLLs versus the platform
> > PLL, with the latter described as sysclk in the hw docs.
> > 
> > Update the qoriq-clock binding to allow a second input clock, named
> > "coreclk".  If present, this clock will be used for the core PLLs.
> > 
> > Signed-off-by: Scott Wood <oss@buserror.net>
> > Cc: devicetree@vger.kernel.org
> > ---
> >  Documentation/devicetree/bindings/clock/qoriq-clock.txt | 6 ++++++
> >  1 file changed, 6 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> > b/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> > index df9cb5a..97a9666 100644
> > --- a/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> > +++ b/Documentation/devicetree/bindings/clock/qoriq-clock.txt
> > @@ -55,6 +55,11 @@ Optional properties:
> >  - clocks: If clock-frequency is not specified, sysclk may be provided
> >  	as an input clock.  Either clock-frequency or clocks must be
> >  	provided.
> > +	A second input clock, called "coreclk", may be provided if
> > +	core PLLs are based on a different input clock from the
> > +	platform PLL.
> > +- clock-names: Required if a coreclk is present.  Valid names are
> > +	"sysclk" and "coreclk".
> 'clk' part is redundant.

"sysclk" is a term used by the hardware documentation and I'd rather leave it
intact.  "coreclk" isn't named (only described) by the hardware documentation
but it is a special variant of sysclk and having similar naming helps make
that clear.

-Scott