clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks

Add support for the AP sub-system clock controller in the T-Head TH1520.
This include CPU, DPU, GMAC and TEE PLLs.

Link: https://openbeagle.org/beaglev-ahead/beaglev-ahead/-/blob/main/docs/TH1520%20System%20User%20Manual.pdf
Co-developed-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Co-developed-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Link: https://git.beagleboard.org/beaglev-ahead/beaglev-ahead/-/tree/main/docs
Signed-off-by: Drew Fustini <dfustini@tenstorrent.com>
Link: https://lore.kernel.org/r/20240711-th1520-clk-v3-2-6ff17bb318fb@tenstorrent.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: tt-fustini

MAINTAINERS

@@ -19324,6 +19324,7 @@ L:	linux-riscv@lists.infradead.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/clock/thead,th1520-clk-ap.yaml
 F:	arch/riscv/boot/dts/thead/
+F:	drivers/clk/thead/clk-th1520-ap.c
 F:	include/dt-bindings/clock/thead,th1520-clk-ap.h
 
 RNBD BLOCK DRIVERS

drivers/clk/Kconfig

@@ -495,6 +495,7 @@ source "drivers/clk/starfive/Kconfig"
 source "drivers/clk/sunxi/Kconfig"
 source "drivers/clk/sunxi-ng/Kconfig"
 source "drivers/clk/tegra/Kconfig"
+source "drivers/clk/thead/Kconfig"
 source "drivers/clk/stm32/Kconfig"
 source "drivers/clk/ti/Kconfig"
 source "drivers/clk/uniphier/Kconfig"

drivers/clk/Makefile

@@ -127,6 +127,7 @@ obj-y					+= starfive/
 obj-$(CONFIG_ARCH_SUNXI)		+= sunxi/
 obj-y					+= sunxi-ng/
 obj-$(CONFIG_ARCH_TEGRA)		+= tegra/
+obj-$(CONFIG_ARCH_THEAD)		+= thead/
 obj-y					+= ti/
 obj-$(CONFIG_CLK_UNIPHIER)		+= uniphier/
 obj-$(CONFIG_ARCH_U8500)		+= ux500/

drivers/clk/thead/Kconfig

@@ -0,0 +1,12 @@
+#SPDX-License-Identifier: GPL-2.0
+
+config CLK_THEAD_TH1520_AP
+	bool "T-HEAD TH1520 AP clock support"
+	depends on ARCH_THEAD || COMPILE_TEST
+	default ARCH_THEAD
+	select REGMAP_MMIO
+	help
+	  Say yes here to support the AP sub system clock controller
+	  on the T-HEAD TH1520 SoC. This includes configuration of
+	  both CPU PLLs, both DPU PLLs as well as the GMAC, VIDEO,
+	  and TEE PLLs.

drivers/clk/thead/Makefile

@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_CLK_THEAD_TH1520_AP) += clk-th1520-ap.o