[RFC PATCH 0/2] sh: Add Casio fx-9750GIII board support

[RFC PATCH 0/2] sh: Add Casio fx-9750GIII board support

[Artem Novak]

Add initial board support for the Casio fx-9750GIII graphing calculator,
based on the Renesas SH7305 (SH4A) processor.

The series introduces the board Device Tree 
and minimal SuperH machine registration.

The Casio board Device Tree binding
has been submitted separately.

This RFC depends on SH7305 CPU and SoC support,
which is not yet available upstream.

The board Device Tree passes dtbs_check, and the machine vector compiles using
Casio GCC 14.3.0. The two patches also apply cleanly to Linux v7.3-rc2.
Hardware boot testing with an unmodified upstream kernel has not yet been
accomplished.

I need comments, they are obviously welcome.

Artem Novak (2):
  sh: dts: add Casio fx-9750GIII board
  sh: fx9750giii: add board support

 arch/sh/Makefile                        |  1 +
 arch/sh/boards/Kconfig                  | 12 ++++++++++++
 arch/sh/boards/Makefile                 |  1 +
 arch/sh/boards/mach-fx9750giii/Makefile |  2 ++
 arch/sh/boards/mach-fx9750giii/setup.c  | 14 ++++++++++++++
 arch/sh/boot/dts/Makefile               |  1 +
 arch/sh/boot/dts/fx9750giii.dts         | 15 +++++++++++++++
 7 files changed, 46 insertions(+)
 create mode 100644 arch/sh/boards/mach-fx9750giii/Makefile
 create mode 100644 arch/sh/boards/mach-fx9750giii/setup.c
 create mode 100644 arch/sh/boot/dts/fx9750giii.dts

-- 
2.56.0

[RFC PATCH 1/2] sh: dts: add Casio fx-9750GIII board

[Artem Novak]

Describe the Casio fx-9750GIII graphing calculator, which uses the Renesas SH7305 processor.

Added the board Device Tree and its DTB build rule.
The description uses existing SH7305 SoC include
and affirm the calculator memory region.

Signed-off-by: Artem Novak <artem122novak@gmail.com>
---
 arch/sh/boot/dts/Makefile       |  1 +
 arch/sh/boot/dts/fx9750giii.dts | 15 +++++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 arch/sh/boot/dts/fx9750giii.dts

diff --git a/arch/sh/boot/dts/Makefile b/arch/sh/boot/dts/Makefile
index d109978a5eb9..4887fb16dbf2 100644
--- a/arch/sh/boot/dts/Makefile
+++ b/arch/sh/boot/dts/Makefile
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
+dtb-$(CONFIG_SH_FX9750GIII) += fx9750giii.dtb
 obj-$(CONFIG_BUILTIN_DTB) += $(addsuffix .dtb.o, $(CONFIG_BUILTIN_DTB_NAME))
diff --git a/arch/sh/boot/dts/fx9750giii.dts b/arch/sh/boot/dts/fx9750giii.dts
new file mode 100644
index 000000000000..bccae22e4899
--- /dev/null
+++ b/arch/sh/boot/dts/fx9750giii.dts
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2026 Artem Novak
+/dts-v1/;
+
+#include "sh7305.dtsi"
+
+/ {
+	model = "Casio fx-9750GIII";
+	compatible = "casio,fx-9750giii", "renesas,sh7305";
+
+	memory@8000000 {
+		device_type = "memory";
+		reg = <0x08000000 0x00080000>;
+	};
+};
-- 
2.56.0

[RFC PATCH 2/2] sh: fx9750giii: add board support

[Artem Novak]

Add minimal machine support for the Casio fx-9750GIII graphing calculator.

Introducing a board Kconfig option and registration on its machine vector.
Wire the board directory into the SuperH build system.

Signed-off-by: Artem Novak <artem122novak@gmail.com>
---
 arch/sh/Makefile                        |  1 +
 arch/sh/boards/Kconfig                  | 12 ++++++++++++
 arch/sh/boards/Makefile                 |  1 +
 arch/sh/boards/mach-fx9750giii/Makefile |  2 ++
 arch/sh/boards/mach-fx9750giii/setup.c  | 14 ++++++++++++++
 5 files changed, 30 insertions(+)
 create mode 100644 arch/sh/boards/mach-fx9750giii/Makefile
 create mode 100644 arch/sh/boards/mach-fx9750giii/setup.c

diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index 380e3b7dc597..28b431a8c8d9 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -128,6 +128,7 @@ machdir-$(CONFIG_SH_KFR2R09)			+= mach-kfr2r09
 machdir-$(CONFIG_SH_ECOVEC)			+= mach-ecovec24
 machdir-$(CONFIG_SH_SDK7786)			+= mach-sdk7786
 machdir-$(CONFIG_SH_X3PROTO)			+= mach-x3proto
+machdir-$(CONFIG_SH_FX9750GIII)		+= mach-fx9750giii
 machdir-$(CONFIG_SH_LANDISK)			+= mach-landisk
 machdir-y					+= mach-common
 
diff --git a/arch/sh/boards/Kconfig b/arch/sh/boards/Kconfig
index d89b74177233..f1571b0e5f1f 100644
--- a/arch/sh/boards/Kconfig
+++ b/arch/sh/boards/Kconfig
@@ -326,6 +326,18 @@ config SH_LBOX_RE2
 	help
 	  Select L-BOX RE2 if configuring for the NTT COMWARE L-BOX RE2.
 
+
+config SH_FX9750GIII
+	bool "Casio fx-9750GIII"
+	depends on CPU_SUBTYPE_SH7305
+	select OF
+	select OF_EARLY_FLATTREE
+	help
+	  Enable board support for the Casio fx-9750GIII
+	  graphing calculator, based on the Renesas SH7305.
+	  This selects the calculator machine vector and
+	  enables early Device Tree support for the board.
+
 config SH_X3PROTO
 	bool "SH-X3 Prototype board"
 	depends on CPU_SUBTYPE_SHX3
diff --git a/arch/sh/boards/Makefile b/arch/sh/boards/Makefile
index fbbc350ca854..c60d038872e9 100644
--- a/arch/sh/boards/Makefile
+++ b/arch/sh/boards/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_SH_ECOVEC)		+= mach-ecovec24/
 obj-$(CONFIG_SH_SDK7780)	+= mach-sdk7780/
 obj-$(CONFIG_SH_SDK7786)	+= mach-sdk7786/
 obj-$(CONFIG_SH_X3PROTO)	+= mach-x3proto/
+obj-$(CONFIG_SH_FX9750GIII)	+= mach-fx9750giii/
 obj-$(CONFIG_SH_SH7763RDP)	+= mach-sh7763rdp/
 obj-$(CONFIG_SH_LANDISK)	+= mach-landisk/
 obj-$(CONFIG_SH_LBOX_RE2)	+= mach-lboxre2/
diff --git a/arch/sh/boards/mach-fx9750giii/Makefile b/arch/sh/boards/mach-fx9750giii/Makefile
new file mode 100644
index 000000000000..0d6df7044567
--- /dev/null
+++ b/arch/sh/boards/mach-fx9750giii/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y += setup.o
diff --git a/arch/sh/boards/mach-fx9750giii/setup.c b/arch/sh/boards/mach-fx9750giii/setup.c
new file mode 100644
index 000000000000..233decdd1bfe
--- /dev/null
+++ b/arch/sh/boards/mach-fx9750giii/setup.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2026 Artem Novak
+/*
+ * Casio fx-9750GIII platform support
+ *
+ */
+
+#include <linux/init.h>
+
+#include <asm/machvec.h>
+
+static struct sh_machine_vector mv_fx9750giii __initmv = {
+	.mv_name	= "Casio fx-9750GIII",
+};
-- 
2.56.0