soc/mediatek/mt8196: Add mt6363_read8 API

Add mt6363_read8 API for common use.

BUG=b:317009620
TEST=Build pass.

Change-Id: I3cca4c2e5f6c2537c9661623260b21fb6088eff9
Signed-off-by: Hope Wang <hope.wang@mediatek.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/85892
Reviewed-by: Yidi Lin <yidilin@google.com>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/mediatek/common/include/soc/mt6363.h

@@ -109,6 +109,7 @@ void mt6363_enable_vram_digrf(bool enable);
 void mt6363_enable_vram_mdfe(bool enable);
 void mt6363_init_pmif_arb(void);
 u16 mt6363_read16(u32 reg);
+u8 mt6363_read8(u32 reg);
 void mt6363_write8(u32 reg, u8 reg_val);
 void mt6363_write_field(u32 reg, u32 val, u32 mask, u32 shift);
 void mt6363_init_setting(void);

src/soc/mediatek/common/mt6363.c

@@ -34,6 +34,16 @@ u16 mt6363_read16(u32 reg)
 	return rdata;
 }
 
+u8 mt6363_read8(u32 reg)
+{
+	u32 rdata = 0;
+
+	assert(pmif_arb);
+	pmif_arb->read(pmif_arb, SPMI_SLAVE_4, reg, &rdata);
+
+	return (u8)rdata;
+}
+
 void mt6363_write8(u32 reg, u8 data)
 {
 	assert(pmif_arb);