soc: mediatek: Add MediaTek DVFS Resource Collector (DVFSRC) driver

The Dynamic Voltage and Frequency Scaling Resource Collector (DVFSRC) is a
Hardware module used to collect all the requests from both software and the
various remote processors embedded into the SoC and decide about a minimum
operating voltage and a minimum DRAM frequency to fulfill those requests in
an effort to provide the best achievable performance per watt.

This hardware IP is capable of transparently performing direct register R/W
on all of the DVFSRC-controlled regulators and SoC bandwidth knobs.

This driver includes support for MT8183, MT8192 and MT8195.

Co-Developed-by: Dawei Chien <dawei.chien@mediatek.com>
[Angelo: Partial refactoring and cleanups]
Reviewed-by: Georgi Djakov <djakov@kerenl.org>
Link: https://lore.kernel.org/r/20240610085735.147134-5-angelogioacchino.delregno@collabora.com
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Author: AngeloGioacchino Del Regno

drivers/soc/mediatek/Kconfig

@@ -26,6 +26,17 @@ config MTK_DEVAPC
 	  The violation information is logged for further analysis or
 	  countermeasures.
 
+config MTK_DVFSRC
+	tristate "MediaTek DVFSRC Support"
+	depends on ARCH_MEDIATEK
+	help
+	  Say yes here to add support for the MediaTek Dynamic Voltage
+	  and Frequency Scaling Resource Collector (DVFSRC): a HW
+	  IP found on many MediaTek SoCs, which is responsible for
+	  collecting DVFS requests from various SoC IPs, other than
+	  software, and performing bandwidth scaling to provide the
+	  best achievable performance-per-watt.
+
 config MTK_INFRACFG
 	bool "MediaTek INFRACFG Support"
 	select REGMAP

drivers/soc/mediatek/Makefile

@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_MTK_CMDQ) += mtk-cmdq-helper.o
 obj-$(CONFIG_MTK_DEVAPC) += mtk-devapc.o
+obj-$(CONFIG_MTK_DVFSRC) += mtk-dvfsrc.o
 obj-$(CONFIG_MTK_INFRACFG) += mtk-infracfg.o
 obj-$(CONFIG_MTK_PMIC_WRAP) += mtk-pmic-wrap.o
 obj-$(CONFIG_MTK_REGULATOR_COUPLER) += mtk-regulator-coupler.o