[PATCH 2/4] soc: toshiba: tc9564: add a new syscon driver

[Alex Elder <elder@riscstar.com>]

Introduce a new system controller driver for devices found within the
Toshiba TC9564 SoC.  The system controller manages access to an 8 KB
region, and implements controllers for a set of clocks as well as a
set of resets.  The region also includes registers that indicate when
initialization is done for the chip's two Ethernet interfaces.

The SoC has a single 25 MHz input clock, and from that derives clocks
of various rates used by functional blocks within the chip.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 MAINTAINERS                         |  1 +
 drivers/soc/Kconfig                 |  1 +
 drivers/soc/Makefile                |  1 +
 drivers/soc/toshiba/Kconfig         | 12 +++++++++
 drivers/soc/toshiba/Makefile        |  3 +++
 drivers/soc/toshiba/tc9564-syscon.c | 42 +++++++++++++++++++++++++++++
 6 files changed, 60 insertions(+)
 create mode 100644 drivers/soc/toshiba/Kconfig
 create mode 100644 drivers/soc/toshiba/Makefile
 create mode 100644 drivers/soc/toshiba/tc9564-syscon.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 2b1b29169e0e9..c25ee6e0f1c68 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -28345,6 +28345,7 @@ M:	Alex Elder <elder@kernel.org>
 M:	Daniel Thompson <danielt@kernel.org>
 S:	Maintained
 F:	Documentation/devicetree/bindings/soc/toshiba/toshiba,tc9564-config-syscon.yaml
+F:	drivers/soc/toshiba/tc9564-syscon.c
 F:	include/dt-bindings/soc/toshiba,tc9564.h
 
 TOSHIBA WMI HOTKEYS DRIVER
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 483cbdcae1534..f655d368e0fb6 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -29,6 +29,7 @@ source "drivers/soc/starfive/Kconfig"
 source "drivers/soc/sunxi/Kconfig"
 source "drivers/soc/tegra/Kconfig"
 source "drivers/soc/ti/Kconfig"
+source "drivers/soc/toshiba/Kconfig"
 source "drivers/soc/ux500/Kconfig"
 source "drivers/soc/versatile/Kconfig"
 source "drivers/soc/vt8500/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 5a3efd68355cd..150f7f4f05560 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -35,6 +35,7 @@ obj-y				+= starfive/
 obj-y				+= sunxi/
 obj-$(CONFIG_ARCH_TEGRA)	+= tegra/
 obj-y				+= ti/
+obj-y				+= toshiba/
 obj-$(CONFIG_ARCH_U8500)	+= ux500/
 obj-y				+= versatile/
 obj-y				+= vt8500/
diff --git a/drivers/soc/toshiba/Kconfig b/drivers/soc/toshiba/Kconfig
new file mode 100644
index 0000000000000..91adcbe71905c
--- /dev/null
+++ b/drivers/soc/toshiba/Kconfig
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config SOC_TOSHIBA_TC9564_SYSCON
+	tristate "Toshiba TC9564 config system controller support"
+	depends on TC9564_PCI
+	depends on MFD_CORE
+	default TC9564_PCI
+	help
+	  This enables support for the config system controller for the
+	  TC9564 SoC.  It implements an MMIO regmap to manage access to
+	  two pages of I/O memory, and serves as a clock and reset
+	  controller for IP blocks within the chip.
diff --git a/drivers/soc/toshiba/Makefile b/drivers/soc/toshiba/Makefile
new file mode 100644
index 0000000000000..18dc03507b320
--- /dev/null
+++ b/drivers/soc/toshiba/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_SOC_TOSHIBA_TC9564_SYSCON)	+= tc9564-syscon.o
diff --git a/drivers/soc/toshiba/tc9564-syscon.c b/drivers/soc/toshiba/tc9564-syscon.c
new file mode 100644
index 0000000000000..0d0e2422b82d0
--- /dev/null
+++ b/drivers/soc/toshiba/tc9564-syscon.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (C) 2026 by RISCstar Solutions Corporation.  All rights reserved.
+ */
+
+#include <linux/device.h>
+#include <linux/device-id/of.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+static const struct mfd_cell tc9564_config_syscon_cells[] = {
+	MFD_CELL_NAME("toshiba-tc9564-clock"),
+	MFD_CELL_NAME("toshiba-tc9564-reset"),
+};
+
+static int tc9564_config_syscon_probe(struct platform_device *pdev)
+{
+	return devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
+				    tc9564_config_syscon_cells,
+				    ARRAY_SIZE(tc9564_config_syscon_cells),
+				    NULL, 0, NULL);
+}
+
+static const struct of_device_id tc9564_config_syscon_match[] = {
+	{ .compatible = "toshiba,tc9564-config-syscon", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, tc9564_config_syscon_match);
+
+static struct platform_driver tc9564_config_syscon_driver = {
+	.driver = {
+		.name		= KBUILD_MODNAME,
+		.of_match_table	= tc9564_config_syscon_match,
+	},
+	.probe = tc9564_config_syscon_probe,
+};
+module_platform_driver(tc9564_config_syscon_driver);
+
+MODULE_DESCRIPTION("Toshiba TC9564 config syscon driver");
+MODULE_LICENSE("GPL");
-- 
2.53.0