soc/mediatek/mt8196: Add vcore DVFS settings

Add vcore settings, so that other tinysys (such as mcupm, spm, etc.)
will reference these value during initialization.

BUG=b:343878736
TEST=Build pass, boot successful. Check log with:
[INFO]	Vcore DVFS settings done

Change-Id: I0d3e1d6ea648af938d41a5c9461cdd2972371177
Signed-off-by: Kunlong Wang <kunlong.wang@mediatek.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/86070
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yidi Lin <yidilin@google.com>

src/soc/mediatek/mt8196/Makefile.mk

@@ -29,6 +29,7 @@ romstage-y += clkbuf_ctl.c
 romstage-y += ../common/dram_init.c
 romstage-y += ../common/dramc_param.c
 romstage-y += dvfs.c
+romstage-y += dvfsrc.c
 romstage-$(CONFIG_PCI) += ../common/early_init.c ../common/pcie.c
 romstage-y += ../common/emi.c
 romstage-y += irq2axi.c

src/soc/mediatek/mt8196/dvfsrc.c

@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+
+#include <console/console.h>
+#include <device/mmio.h>
+#include <soc/addressmap.h>
+#include <soc/dvfsrc.h>
+
+void dvfsrc_opp_level_mapping(void)
+{
+	setbits32p(DVFSRC_RSRV_4, BIT(VCORE_B0_SHIFT));
+	printk(BIOS_INFO, "Vcore DVFS settings done\n");
+}

src/soc/mediatek/mt8196/include/soc/addressmap.h

@@ -156,6 +156,7 @@ enum {
 	SPM_PBUS_BASE		= IO_PHYS + 0x0C00D000,
 	RGU_BASE		= IO_PHYS + 0x0C010000,
 	RC_BASE			= IO_PHYS + 0x0C011000,
+	DVFSRC_BASE		= IO_PHYS + 0x0C013000,
 	GPT_BASE		= IO_PHYS + 0x0C015000,
 	VLP_CKSYS_BASE		= IO_PHYS + 0x0C016000,
 	PMIF_SPMI_P_BASE	= IO_PHYS + 0x0C018000,

src/soc/mediatek/mt8196/include/soc/dvfsrc.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+
+#ifndef SOC_MEDIATEK_MT8196_MTK_VCORE
+#define SOC_MEDIATEK_MT8196_MTK_VCORE
+
+#define DVFSRC_RSRV_4		(DVFSRC_BASE + 0x290)
+#define VCORE_B0_SHIFT		23
+
+void dvfsrc_opp_level_mapping(void);
+
+#endif