[PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Torsten Duwe]

Devicetree commit a198185b9b5 introduced a new type of clock,
"gated-fixed-clock", for which Das U-Boot does not have
a driver yet. The required code is similar to gpio-gate-clock,
and can be added using little extra text space.

Use this code e.g. to boot a Rock5 ITX from NVMe

Signed-off-by: Torsten Duwe <duwe@lst.de>
---
Hi all,

I have a Rock 5 ITX, too, and got struck by Heiko's change ;)
Instead of Copy & Waste I merged the required changes into 
clk-gpio, which results in 121 extra code bytes and a driver
which accepts a superset of both DT bindings.

 size clk-gated-fixed.o clk-gpio*.o
   text	   data	    bss	    dec	    hex	filename
    673	    120	      0	    793	    319	clk-gated-fixed.o
    665	    120	      0	    785	    311	clk-gpio.o
    544	    120	      0	    664	    298	clk-gpio-orig.o

All I want to do here is present it as an alternative to Daniele's
approach[1] and let the maintainers decide how to proceed. This is 
a "works for me" raw cut, feel free to review if we want to go this
way.

	Torsten

[1] https://lists.denx.de/pipermail/u-boot/2026-May/619110.html
---
 configs/rock-5-itx-rk3588_defconfig |  1 +
 drivers/clk/clk-gpio.c              | 29 ++++++++++++++++++++++-------
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/configs/rock-5-itx-rk3588_defconfig b/configs/rock-5-itx-rk3588_defconfig
index cb014de4188..adb20c2f3a0 100644
--- a/configs/rock-5-itx-rk3588_defconfig
+++ b/configs/rock-5-itx-rk3588_defconfig
@@ -52,6 +52,7 @@ CONFIG_AHCI=y
 CONFIG_AHCI_PCI=y
 CONFIG_DWC_AHCI=y
 CONFIG_SPL_CLK=y
+CONFIG_CLK_GPIO=y
 # CONFIG_USB_FUNCTION_FASTBOOT is not set
 CONFIG_ROCKCHIP_GPIO=y
 CONFIG_SYS_I2C_ROCKCHIP=y
diff --git a/drivers/clk/clk-gpio.c b/drivers/clk/clk-gpio.c
index 4ed14306575..b7abc891ed2 100644
--- a/drivers/clk/clk-gpio.c
+++ b/drivers/clk/clk-gpio.c
@@ -6,6 +6,7 @@
 #include <clk.h>
 #include <clk-uclass.h>
 #include <dm.h>
+#include <power/regulator.h>
 #include <linux/clk-provider.h>
 
 #include <asm/gpio.h>
@@ -13,14 +14,18 @@
 struct clk_gpio_priv {
 	struct gpio_desc	enable;	/* GPIO, controlling the gate */
 	struct clk		*clk;	/* Gated clock */
+	struct udevice		*vdd_supply;
 };
 
 static int clk_gpio_enable(struct clk *clk)
 {
 	struct clk_gpio_priv *priv = dev_get_priv(clk->dev);
 
-	clk_enable(priv->clk);
-	dm_gpio_set_value(&priv->enable, 1);
+	if (priv->clk)
+		clk_enable(priv->clk);
+
+	if (priv->enable.dev)
+		dm_gpio_set_value(&priv->enable, 1);
 
 	return 0;
 }
@@ -29,8 +34,11 @@ static int clk_gpio_disable(struct clk *clk)
 {
 	struct clk_gpio_priv *priv = dev_get_priv(clk->dev);
 
-	dm_gpio_set_value(&priv->enable, 0);
-	clk_disable(priv->clk);
+	if (priv->enable.dev)
+		dm_gpio_set_value(&priv->enable, 0);
+
+	if (priv->clk)
+		clk_disable(priv->clk);
 
 	return 0;
 }
@@ -39,7 +47,7 @@ static ulong clk_gpio_get_rate(struct clk *clk)
 {
 	struct clk_gpio_priv *priv = dev_get_priv(clk->dev);
 
-	return clk_get_rate(priv->clk);
+	return (priv->clk) ? clk_get_rate(priv->clk) : -1;
 }
 
 const struct clk_ops clk_gpio_ops = {
@@ -57,7 +65,7 @@ static int clk_gpio_probe(struct udevice *dev)
 	if (IS_ERR(priv->clk)) {
 		log_debug("%s: Could not get gated clock: %ld\n",
 			  __func__, PTR_ERR(priv->clk));
-		return PTR_ERR(priv->clk);
+		priv->clk = 0;
 	}
 
 	ret = gpio_request_by_name(dev, "enable-gpios", 0,
@@ -65,9 +73,15 @@ static int clk_gpio_probe(struct udevice *dev)
 	if (ret) {
 		log_debug("%s: Could not decode enable-gpios (%d)\n",
 			  __func__, ret);
-		return ret;
 	}
 
+	ret = device_get_supply_regulator(dev, "vdd-supply",
+					  &priv->vdd_supply);
+	if (ret == 0)
+		ret = regulator_set_enable(priv->vdd_supply, true);
+
+	log_debug("%s: %s regulator = %d\n", __func__, dev->name, ret);
+
 	return 0;
 }
 
@@ -80,6 +94,7 @@ static int clk_gpio_probe(struct udevice *dev)
  */
 static const struct udevice_id clk_gpio_match[] = {
 	{ .compatible = "gpio-gate-clock" },
+	{ .compatible = "gated-fixed-clock" },
 	{ /* sentinel */ }
 };
 
-- 
2.54.0

Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Jonas Karlman]

Hi Torsten,

On 5/28/2026 1:22 PM, Torsten Duwe wrote:
> 
> Devicetree commit a198185b9b5 introduced a new type of clock,
> "gated-fixed-clock", for which Das U-Boot does not have
> a driver yet. The required code is similar to gpio-gate-clock,
> and can be added using little extra text space.
> 
> Use this code e.g. to boot a Rock5 ITX from NVMe
> 
> Signed-off-by: Torsten Duwe <duwe@lst.de>
> ---
> Hi all,
> 
> I have a Rock 5 ITX, too, and got struck by Heiko's change ;)
> Instead of Copy & Waste I merged the required changes into 
> clk-gpio, which results in 121 extra code bytes and a driver
> which accepts a superset of both DT bindings.
> 
>  size clk-gated-fixed.o clk-gpio*.o
>    text	   data	    bss	    dec	    hex	filename
>     673	    120	      0	    793	    319	clk-gated-fixed.o
>     665	    120	      0	    785	    311	clk-gpio.o
>     544	    120	      0	    664	    298	clk-gpio-orig.o
> 
> All I want to do here is present it as an alternative to Daniele's
> approach[1] and let the maintainers decide how to proceed. This is 
> a "works for me" raw cut, feel free to review if we want to go this
> way.
> 
> 	Torsten
> 
> [1] https://lists.denx.de/pipermail/u-boot/2026-May/619110.html
> ---
>  configs/rock-5-itx-rk3588_defconfig |  1 +
>  drivers/clk/clk-gpio.c              | 29 ++++++++++++++++++++++-------
>  2 files changed, 23 insertions(+), 7 deletions(-)
> 
> diff --git a/configs/rock-5-itx-rk3588_defconfig b/configs/rock-5-itx-rk3588_defconfig
> index cb014de4188..adb20c2f3a0 100644
> --- a/configs/rock-5-itx-rk3588_defconfig
> +++ b/configs/rock-5-itx-rk3588_defconfig
> @@ -52,6 +52,7 @@ CONFIG_AHCI=y
>  CONFIG_AHCI_PCI=y
>  CONFIG_DWC_AHCI=y
>  CONFIG_SPL_CLK=y
> +CONFIG_CLK_GPIO=y
>  # CONFIG_USB_FUNCTION_FASTBOOT is not set
>  CONFIG_ROCKCHIP_GPIO=y
>  CONFIG_SYS_I2C_ROCKCHIP=y
> diff --git a/drivers/clk/clk-gpio.c b/drivers/clk/clk-gpio.c
> index 4ed14306575..b7abc891ed2 100644
> --- a/drivers/clk/clk-gpio.c
> +++ b/drivers/clk/clk-gpio.c
> @@ -6,6 +6,7 @@
>  #include <clk.h>
>  #include <clk-uclass.h>
>  #include <dm.h>
> +#include <power/regulator.h>
>  #include <linux/clk-provider.h>
>  
>  #include <asm/gpio.h>
> @@ -13,14 +14,18 @@
>  struct clk_gpio_priv {
>  	struct gpio_desc	enable;	/* GPIO, controlling the gate */
>  	struct clk		*clk;	/* Gated clock */
> +	struct udevice		*vdd_supply;
>  };
>  
>  static int clk_gpio_enable(struct clk *clk)
>  {
>  	struct clk_gpio_priv *priv = dev_get_priv(clk->dev);
>  
> -	clk_enable(priv->clk);
> -	dm_gpio_set_value(&priv->enable, 1);
> +	if (priv->clk)
> +		clk_enable(priv->clk);
> +
> +	if (priv->enable.dev)
> +		dm_gpio_set_value(&priv->enable, 1);
>  
>  	return 0;
>  }
> @@ -29,8 +34,11 @@ static int clk_gpio_disable(struct clk *clk)
>  {
>  	struct clk_gpio_priv *priv = dev_get_priv(clk->dev);
>  
> -	dm_gpio_set_value(&priv->enable, 0);
> -	clk_disable(priv->clk);
> +	if (priv->enable.dev)
> +		dm_gpio_set_value(&priv->enable, 0);
> +
> +	if (priv->clk)
> +		clk_disable(priv->clk);
>  
>  	return 0;
>  }
> @@ -39,7 +47,7 @@ static ulong clk_gpio_get_rate(struct clk *clk)
>  {
>  	struct clk_gpio_priv *priv = dev_get_priv(clk->dev);
>  
> -	return clk_get_rate(priv->clk);
> +	return (priv->clk) ? clk_get_rate(priv->clk) : -1;
>  }
>  
>  const struct clk_ops clk_gpio_ops = {
> @@ -57,7 +65,7 @@ static int clk_gpio_probe(struct udevice *dev)
>  	if (IS_ERR(priv->clk)) {
>  		log_debug("%s: Could not get gated clock: %ld\n",
>  			  __func__, PTR_ERR(priv->clk));
> -		return PTR_ERR(priv->clk);
> +		priv->clk = 0;
>  	}
>  
>  	ret = gpio_request_by_name(dev, "enable-gpios", 0,
> @@ -65,9 +73,15 @@ static int clk_gpio_probe(struct udevice *dev)
>  	if (ret) {
>  		log_debug("%s: Could not decode enable-gpios (%d)\n",
>  			  __func__, ret);
> -		return ret;
>  	}
>  
> +	ret = device_get_supply_regulator(dev, "vdd-supply",
> +					  &priv->vdd_supply);
> +	if (ret == 0)
> +		ret = regulator_set_enable(priv->vdd_supply, true);

You should use regulator_set_enable_if_allowed() and also only enable
and disable the regulator in clk enable and disable ops to keep a
balanced enable ref-count of the regulator.

Regards,
Jonas

> +
> +	log_debug("%s: %s regulator = %d\n", __func__, dev->name, ret);
> +
>  	return 0;
>  }
>  
> @@ -80,6 +94,7 @@ static int clk_gpio_probe(struct udevice *dev)
>   */
>  static const struct udevice_id clk_gpio_match[] = {
>  	{ .compatible = "gpio-gate-clock" },
> +	{ .compatible = "gated-fixed-clock" },
>  	{ /* sentinel */ }
>  };
>  

Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Tom Rini]

On Thu, 28 May 2026 13:22:06 +0200, Torsten Duwe wrote:

> Devicetree commit a198185b9b5 introduced a new type of clock,
> "gated-fixed-clock", for which Das U-Boot does not have
> a driver yet. The required code is similar to gpio-gate-clock,
> and can be added using little extra text space.
> 
> Use this code e.g. to boot a Rock5 ITX from NVMe
> 
> [...]

Applied to u-boot/next, thanks!

[1/1] clk: enhance clk-gpio to also handle gated-fixed-clock
      commit: 4e249b94af928aca29972fc22ef2b5ed0016eab9
-- 
Tom

Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Jonas Karlman]

Hi Tom,

On 6/11/2026 3:48 PM, Tom Rini wrote:
> On Thu, 28 May 2026 13:22:06 +0200, Torsten Duwe wrote:
> 
>> Devicetree commit a198185b9b5 introduced a new type of clock,
>> "gated-fixed-clock", for which Das U-Boot does not have
>> a driver yet. The required code is similar to gpio-gate-clock,
>> and can be added using little extra text space.
>>
>> Use this code e.g. to boot a Rock5 ITX from NVMe
>>
>> [...]
> 
> Applied to u-boot/next, thanks!

Any reason this was applied without my review concerns being addressed?

Please revert, or address the issues this patch have :-)

Regards,
Jonas

> 
> [1/1] clk: enhance clk-gpio to also handle gated-fixed-clock
>       commit: 4e249b94af928aca29972fc22ef2b5ed0016eab9

Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 796 bytes --]

On Thu, Jun 11, 2026 at 03:58:04PM +0200, Jonas Karlman wrote:
> Hi Tom,
> 
> On 6/11/2026 3:48 PM, Tom Rini wrote:
> > On Thu, 28 May 2026 13:22:06 +0200, Torsten Duwe wrote:
> > 
> >> Devicetree commit a198185b9b5 introduced a new type of clock,
> >> "gated-fixed-clock", for which Das U-Boot does not have
> >> a driver yet. The required code is similar to gpio-gate-clock,
> >> and can be added using little extra text space.
> >>
> >> Use this code e.g. to boot a Rock5 ITX from NVMe
> >>
> >> [...]
> > 
> > Applied to u-boot/next, thanks!
> 
> Any reason this was applied without my review concerns being addressed?
> 
> Please revert, or address the issues this patch have :-)

Yes, I missed them, sorry about that. I'll go push a revert along
shortly.

-- 
Tom

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Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Torsten Duwe]

On Thu, 11 Jun 2026 08:01:05 -0600
Tom Rini <trini@konsulko.com> wrote:

> On Thu, Jun 11, 2026 at 03:58:04PM +0200, Jonas Karlman wrote:
> > Hi Tom,
> > 
> > On 6/11/2026 3:48 PM, Tom Rini wrote:
> > > On Thu, 28 May 2026 13:22:06 +0200, Torsten Duwe wrote:
> > > 
> > >> Devicetree commit a198185b9b5 introduced a new type of clock,
> > >> "gated-fixed-clock", for which Das U-Boot does not have
> > >> a driver yet. The required code is similar to gpio-gate-clock,
> > >> and can be added using little extra text space.
> > >>
> > >> Use this code e.g. to boot a Rock5 ITX from NVMe
> > >>
> > >> [...]
> > > 
> > > Applied to u-boot/next, thanks!
> > 
> > Any reason this was applied without my review concerns being
> > addressed?
> > 
> > Please revert, or address the issues this patch have :-)
> 
> Yes, I missed them, sorry about that. I'll go push a revert along
> shortly.
> 

IIRC it was not a big thing, I can also follow up with the change
suggested by Jonas, if that's easier for you.

	Torsten

Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 1258 bytes --]

On Thu, Jun 11, 2026 at 04:17:55PM +0200, Torsten Duwe wrote:
> On Thu, 11 Jun 2026 08:01:05 -0600
> Tom Rini <trini@konsulko.com> wrote:
> 
> > On Thu, Jun 11, 2026 at 03:58:04PM +0200, Jonas Karlman wrote:
> > > Hi Tom,
> > > 
> > > On 6/11/2026 3:48 PM, Tom Rini wrote:
> > > > On Thu, 28 May 2026 13:22:06 +0200, Torsten Duwe wrote:
> > > > 
> > > >> Devicetree commit a198185b9b5 introduced a new type of clock,
> > > >> "gated-fixed-clock", for which Das U-Boot does not have
> > > >> a driver yet. The required code is similar to gpio-gate-clock,
> > > >> and can be added using little extra text space.
> > > >>
> > > >> Use this code e.g. to boot a Rock5 ITX from NVMe
> > > >>
> > > >> [...]
> > > > 
> > > > Applied to u-boot/next, thanks!
> > > 
> > > Any reason this was applied without my review concerns being
> > > addressed?
> > > 
> > > Please revert, or address the issues this patch have :-)
> > 
> > Yes, I missed them, sorry about that. I'll go push a revert along
> > shortly.
> > 
> 
> IIRC it was not a big thing, I can also follow up with the change
> suggested by Jonas, if that's easier for you.

I've already got the revert made, thanks tho. And again, sorry for the
confusion all.

-- 
Tom

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Re: [PATCH] clk: enhance clk-gpio to also handle gated-fixed-clock

[Jonas Karlman]

Hi Torsten,

On 6/11/2026 4:17 PM, Torsten Duwe wrote:
> On Thu, 11 Jun 2026 08:01:05 -0600
> Tom Rini <trini@konsulko.com> wrote:
> 
>> On Thu, Jun 11, 2026 at 03:58:04PM +0200, Jonas Karlman wrote:
>>> Hi Tom,
>>>
>>> On 6/11/2026 3:48 PM, Tom Rini wrote:
>>>> On Thu, 28 May 2026 13:22:06 +0200, Torsten Duwe wrote:
>>>>
>>>>> Devicetree commit a198185b9b5 introduced a new type of clock,
>>>>> "gated-fixed-clock", for which Das U-Boot does not have
>>>>> a driver yet. The required code is similar to gpio-gate-clock,
>>>>> and can be added using little extra text space.
>>>>>
>>>>> Use this code e.g. to boot a Rock5 ITX from NVMe
>>>>>
>>>>> [...]
>>>>
>>>> Applied to u-boot/next, thanks!
>>>
>>> Any reason this was applied without my review concerns being
>>> addressed?
>>>
>>> Please revert, or address the issues this patch have :-)
>>
>> Yes, I missed them, sorry about that. I'll go push a revert along
>> shortly.
>>
> 
> IIRC it was not a big thing, I can also follow up with the change
> suggested by Jonas, if that's easier for you.

There where three issues with this patch:
- wrong regulator_set_enable function used
- regulator is enabled during probe, not when clock is enabled
- regulator is never disabled, resulting in broken/unbalanced reference
  enable count of the regulator

Also keep in mind that there are some issues with the pcie_dw_rockchip
driver to fully and correctly fix gated-fixed-clock use on ROCK 5 ITX.

https://lore.kernel.org/u-boot/20260520-rock-5-itx-pcie-refclk-dtsi-v3-0-58f2cea72030@superkali.me/

Regards,
Jonas

> 
> 	Torsten