[RFC PATCH v2 3/9] soc: microchip: add mfd drivers for two syscon regions on PolarFire SoC

Conor Dooley
2025-03-21T17:23:31Z

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");