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[PATCH v5 2/9] soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC

Conor Dooley posted 9 patches 2 months ago
There is a newer version of this series
[PATCH v5 2/9] soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC
Posted by Conor Dooley 2 months ago 
From: Conor Dooley <conor.dooley@microchip.com>

The control-scb and mss-top-sysreg regions on PolarFire SoC both fulfill
multiple purposes. The former is used for mailbox functions in addition
to the temperature & voltage sensor while the latter is used for clocks,
resets, interrupt muxing and pinctrl.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 drivers/soc/microchip/Kconfig               | 13 ++++++
 drivers/soc/microchip/Makefile              |  1 +
 drivers/soc/microchip/mpfs-control-scb.c    | 45 +++++++++++++++++++
 drivers/soc/microchip/mpfs-mss-top-sysreg.c | 48 +++++++++++++++++++++
 4 files changed, 107 insertions(+)
 create mode 100644 drivers/soc/microchip/mpfs-control-scb.c
 create mode 100644 drivers/soc/microchip/mpfs-mss-top-sysreg.c

diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
index 19f4b576f822..31d188311e05 100644
--- a/drivers/soc/microchip/Kconfig
+++ b/drivers/soc/microchip/Kconfig
@@ -9,3 +9,16 @@ config POLARFIRE_SOC_SYS_CTRL
 	  module will be called mpfs_system_controller.
 
 	  If unsure, say N.
+
+config POLARFIRE_SOC_SYSCONS
+	bool "PolarFire SoC (MPFS) syscon drivers"
+	default y
+	depends on ARCH_MICROCHIP
+	select MFD_CORE
+	help
+	  These drivers add support for the syscons on PolarFire SoC (MPFS).
+	  Without these drivers core parts of the kernel such as clocks
+	  and resets will not function correctly.
+
+	  If unsure, and on a PolarFire SoC, say y.
+
diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
index 14489919fe4b..1a3a1594b089 100644
--- a/drivers/soc/microchip/Makefile
+++ b/drivers/soc/microchip/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_POLARFIRE_SOC_SYS_CTRL)	+= mpfs-sys-controller.o
+obj-$(CONFIG_POLARFIRE_SOC_SYSCONS)	+= mpfs-control-scb.o mpfs-mss-top-sysreg.o
diff --git a/drivers/soc/microchip/mpfs-control-scb.c b/drivers/soc/microchip/mpfs-control-scb.c
new file mode 100644
index 000000000000..d1a8e79c232e
--- /dev/null
+++ b/drivers/soc/microchip/mpfs-control-scb.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/array_size.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+static const struct mfd_cell mpfs_control_scb_devs[] = {
+	{ .name = "mpfs-tvs", },
+};
+
+static int mpfs_control_scb_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	ret = mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_control_scb_devs,
+			      1, NULL, 0, NULL);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static const struct of_device_id mpfs_control_scb_of_match[] = {
+	{.compatible = "microchip,mpfs-control-scb", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpfs_control_scb_of_match);
+
+static struct platform_driver mpfs_control_scb_driver = {
+	.driver = {
+		.name = "mpfs-control-scb",
+		.of_match_table = mpfs_control_scb_of_match,
+	},
+	.probe = mpfs_control_scb_probe,
+};
+module_platform_driver(mpfs_control_scb_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("PolarFire SoC control scb driver");
diff --git a/drivers/soc/microchip/mpfs-mss-top-sysreg.c b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
new file mode 100644
index 000000000000..9b2e7b84cdba
--- /dev/null
+++ b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/array_size.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+static const struct mfd_cell mpfs_mss_top_sysreg_devs[] = {
+	{ .name = "mpfs-reset", },
+};
+
+static int mpfs_mss_top_sysreg_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	ret = mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_mss_top_sysreg_devs,
+			      1, NULL, 0, NULL);
+	if (ret)
+		return ret;
+
+	if (devm_of_platform_populate(dev))
+		dev_err(dev, "Error populating children\n");
+
+	return 0;
+}
+
+static const struct of_device_id mpfs_mss_top_sysreg_of_match[] = {
+	{.compatible = "microchip,mpfs-mss-top-sysreg", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpfs_mss_top_sysreg_of_match);
+
+static struct platform_driver mpfs_mss_top_sysreg_driver = {
+	.driver = {
+		.name = "mpfs-mss-top-sysreg",
+		.of_match_table = mpfs_mss_top_sysreg_of_match,
+	},
+	.probe = mpfs_mss_top_sysreg_probe,
+};
+module_platform_driver(mpfs_mss_top_sysreg_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_DESCRIPTION("PolarFire SoC mss top sysreg driver");
-- 
2.51.0
Re: [PATCH v5 2/9] soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC
Posted by Claudiu Beznea 1 month, 3 weeks ago 
Hi, Conor,

On 10/13/25 20:45, Conor Dooley wrote:
> From: Conor Dooley <conor.dooley@microchip.com>
> 
> The control-scb and mss-top-sysreg regions on PolarFire SoC both fulfill
> multiple purposes. The former is used for mailbox functions in addition
> to the temperature & voltage sensor while the latter is used for clocks,
> resets, interrupt muxing and pinctrl.
> 
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
>  drivers/soc/microchip/Kconfig               | 13 ++++++
>  drivers/soc/microchip/Makefile              |  1 +
>  drivers/soc/microchip/mpfs-control-scb.c    | 45 +++++++++++++++++++
>  drivers/soc/microchip/mpfs-mss-top-sysreg.c | 48 +++++++++++++++++++++
>  4 files changed, 107 insertions(+)
>  create mode 100644 drivers/soc/microchip/mpfs-control-scb.c
>  create mode 100644 drivers/soc/microchip/mpfs-mss-top-sysreg.c
> 
> diff --git a/drivers/soc/microchip/Kconfig b/drivers/soc/microchip/Kconfig
> index 19f4b576f822..31d188311e05 100644
> --- a/drivers/soc/microchip/Kconfig
> +++ b/drivers/soc/microchip/Kconfig
> @@ -9,3 +9,16 @@ config POLARFIRE_SOC_SYS_CTRL
>  	  module will be called mpfs_system_controller.
>  
>  	  If unsure, say N.
> +
> +config POLARFIRE_SOC_SYSCONS
> +	bool "PolarFire SoC (MPFS) syscon drivers"
> +	default y
> +	depends on ARCH_MICROCHIP
> +	select MFD_CORE
> +	help
> +	  These drivers add support for the syscons on PolarFire SoC (MPFS).
> +	  Without these drivers core parts of the kernel such as clocks
> +	  and resets will not function correctly.
> +
> +	  If unsure, and on a PolarFire SoC, say y.
> +

This empty line could be dropped.

> diff --git a/drivers/soc/microchip/Makefile b/drivers/soc/microchip/Makefile
> index 14489919fe4b..1a3a1594b089 100644
> --- a/drivers/soc/microchip/Makefile
> +++ b/drivers/soc/microchip/Makefile
> @@ -1 +1,2 @@
>  obj-$(CONFIG_POLARFIRE_SOC_SYS_CTRL)	+= mpfs-sys-controller.o
> +obj-$(CONFIG_POLARFIRE_SOC_SYSCONS)	+= mpfs-control-scb.o mpfs-mss-top-sysreg.o
> diff --git a/drivers/soc/microchip/mpfs-control-scb.c b/drivers/soc/microchip/mpfs-control-scb.c
> new file mode 100644
> index 000000000000..d1a8e79c232e
> --- /dev/null
> +++ b/drivers/soc/microchip/mpfs-control-scb.c
> @@ -0,0 +1,45 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/array_size.h>

Looks like this one can be dropped or maybe you want to use
ARRAY_SIZE(mpfs_control_scb_devs) as 4th argument of mfd_add_devices().

> +#include <linux/of.h>
> +#include <linux/of_address.h>

Looks like this one can be dropped.

> +#include <linux/mfd/core.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of_platform.h>

Same with this one?

> +#include <linux/platform_device.h>
> +
> +static const struct mfd_cell mpfs_control_scb_devs[] = {
> +	{ .name = "mpfs-tvs", },

I think you can use:

MFD_CELL_NAME("mpfs-tvs")

> +};
> +
> +static int mpfs_control_scb_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	int ret;
> +
> +	ret = mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_control_scb_devs,
> +			      1, NULL, 0, NULL);
> +	if (ret)
> +		return ret;
> +
> +	return 0;

You can use directly:

	return mfd_add_device(...);

> +}
> +
> +static const struct of_device_id mpfs_control_scb_of_match[] = {
> +	{.compatible = "microchip,mpfs-control-scb", },

This looks un-documented.

> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, mpfs_control_scb_of_match);
> +
> +static struct platform_driver mpfs_control_scb_driver = {
> +	.driver = {
> +		.name = "mpfs-control-scb",
> +		.of_match_table = mpfs_control_scb_of_match,
> +	},
> +	.probe = mpfs_control_scb_probe,
> +};
> +module_platform_driver(mpfs_control_scb_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
> +MODULE_DESCRIPTION("PolarFire SoC control scb driver");
> diff --git a/drivers/soc/microchip/mpfs-mss-top-sysreg.c b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
> new file mode 100644
> index 000000000000..9b2e7b84cdba
> --- /dev/null
> +++ b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
> @@ -0,0 +1,48 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/array_size.h>

Looks like this one can be dropped or maybe you want to use
ARRAY_SIZE(mpfs_mss_top_sysreg_devs) as 4th argument of mfd_add_devices()

> +#include <linux/of.h>
> +#include <linux/of_address.h>

Unused?

> +#include <linux/mfd/core.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of_platform.h>

Unused?

> +#include <linux/platform_device.h>
> +
> +static const struct mfd_cell mpfs_mss_top_sysreg_devs[] = {
> +	{ .name = "mpfs-reset", },

MFD_CELL_NAME() ?

> +};
> +
> +static int mpfs_mss_top_sysreg_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	int ret;
> +
> +	ret = mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_mss_top_sysreg_devs,
> +			      1, NULL, 0, NULL);
> +	if (ret)
> +		return ret;
> +
> +	if (devm_of_platform_populate(dev))
> +		dev_err(dev, "Error populating children\n");

Is it OK return 0 above if there are failures here?

> +
> +	return 0;
> +}
> +
> +static const struct of_device_id mpfs_mss_top_sysreg_of_match[] = {
> +	{.compatible = "microchip,mpfs-mss-top-sysreg", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, mpfs_mss_top_sysreg_of_match);
> +
> +static struct platform_driver mpfs_mss_top_sysreg_driver = {
> +	.driver = {
> +		.name = "mpfs-mss-top-sysreg",
> +		.of_match_table = mpfs_mss_top_sysreg_of_match,
> +	},
> +	.probe = mpfs_mss_top_sysreg_probe,
> +};
> +module_platform_driver(mpfs_mss_top_sysreg_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
> +MODULE_DESCRIPTION("PolarFire SoC mss top sysreg driver");
Re: [PATCH v5 2/9] soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC
Posted by Conor Dooley 1 month, 3 weeks ago 
On Thu, Oct 23, 2025 at 07:04:33AM +0300, Claudiu Beznea wrote:
> On 10/13/25 20:45, Conor Dooley wrote:
> > +++ b/drivers/soc/microchip/mpfs-mss-top-sysreg.c
> > @@ -0,0 +1,48 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +
> > +#include <linux/array_size.h>
> 
> Looks like this one can be dropped or maybe you want to use
> ARRAY_SIZE(mpfs_mss_top_sysreg_devs) as 4th argument of mfd_add_devices()
> 
> > +#include <linux/of.h>
> > +#include <linux/of_address.h>
> 
> Unused?
> 
> > +#include <linux/mfd/core.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/of_platform.h>
> 
> Unused?

This one is where devm_of_platform_populate comes from.

> 
> > +#include <linux/platform_device.h>
> > +
> > +static const struct mfd_cell mpfs_mss_top_sysreg_devs[] = {
> > +	{ .name = "mpfs-reset", },
> 
> MFD_CELL_NAME() ?
> 
> > +};
> > +
> > +static int mpfs_mss_top_sysreg_probe(struct platform_device *pdev)
> > +{
> > +	struct device *dev = &pdev->dev;
> > +	int ret;
> > +
> > +	ret = mfd_add_devices(dev, PLATFORM_DEVID_NONE, mpfs_mss_top_sysreg_devs,
> > +			      1, NULL, 0, NULL);
> > +	if (ret)
> > +		return ret;
> > +
> > +	if (devm_of_platform_populate(dev))
> > +		dev_err(dev, "Error populating children\n");
> 
> Is it OK return 0 above if there are failures here?

I think my rationale was that the mfd devices would be able to keep
working, but I think ultimately it doesn't matter much and I'll change
it.
Re: [PATCH v5 2/9] soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC
Posted by Conor Dooley 1 month, 3 weeks ago 
On Thu, Oct 23, 2025 at 07:04:33AM +0300, Claudiu Beznea wrote:
> On 10/13/25 20:45, Conor Dooley wrote:

> > +}
> > +
> > +static const struct of_device_id mpfs_control_scb_of_match[] = {
> > +	{.compatible = "microchip,mpfs-control-scb", },
> 
> This looks un-documented.

It is actually documented, this stuff all took so long to get done that
parts got applied piecemeal along the way, including any of the MFD
bits.

I'll fix these things up separately, cos I already applied the first two
patches here and just squash it in.

Patchew 2.1-devel-b67e4c2

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