soc/mediatek/mt8186: Add support for regulator VRF12/VCN33

To provide power to PS8640, the eDP bridge IC on krabby, add control
of VRF12 and VCN33 to set voltage from MT6366.

TEST=measure 1.2V from VRF12 and 3.3V from VCN33.
BUG=b:210806060

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Change-Id: I55a9ca16e1e335e9355d0a1b30c278a9969db197
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60446
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>

2 files changed, 79 insertions, 0 deletions

diff --git a/src/soc/mediatek/mt8186/include/soc/mt6366.h b/src/soc/mediatek/mt8186/include/soc/mt6366.h
index af77da225d..2315a24a76 100644
--- a/src/soc/mediatek/mt8186/include/soc/mt6366.h
+++ b/src/soc/mediatek/mt8186/include/soc/mt6366.h
@@ -43,10 +43,14 @@ enum {
 	PMIC_VSRAM_PROC12_OP_EN		= 0x1b90,
 	PMIC_VSRAM_PROC12_DBG0		= 0x1ba2,
 	PMIC_VSRAM_PROC12_VOSEL		= 0x1bf0,
+	PMIC_LDO_VRF12_CON0		= 0x1c30,
+	PMIC_LDO_VRF12_OP_EN		= 0x1c32,
 	PMIC_LDO_VMC_CON0		= 0x1cc4,
 	PMIC_LDO_VMC_OP_EN		= 0x1cc6,
 	PMIC_LDO_VMCH_CON0		= 0x1cd8,
 	PMIC_LDO_VMCH_OP_EN		= 0x1cda,
+	PMIC_LDO_VCN33_CON0_0		= 0x1d1c,
+	PMIC_VCN33_ANA_CON0		= 0x1e28,
 	PMIC_VSIM2_ANA_CON0		= 0x1e30,
 	PMIC_VMCH_ANA_CON0		= 0x1e48,
 	PMIC_VMC_ANA_CON0		= 0x1e4c,
@@ -61,6 +65,8 @@ enum mt6366_regulator_id {
 	MT6366_VMC,
 	MT6366_VPROC12,
 	MT6366_VSRAM_PROC12,
+	MT6366_VRF12,
+	MT6366_VCN33,
 	MT6366_REGULATOR_NUM,
 };
 
diff --git a/src/soc/mediatek/mt8186/mt6366.c b/src/soc/mediatek/mt8186/mt6366.c
index 5cec47a04a..9ca7c05253 100644
--- a/src/soc/mediatek/mt8186/mt6366.c
+++ b/src/soc/mediatek/mt8186/mt6366.c
@@ -705,6 +705,68 @@ static void pmic_set_vmc_vol(u32 vmc_uv)
 	pwrap_write_field(PMIC_LDO_VMC_CON0, 1, 0xFF, 0);
 }
 
+static u32 pmic_get_vrf12_vol(void)
+{
+	return (pwrap_read_field(PMIC_LDO_VRF12_CON0, 0x3, 0) &
+		pwrap_read_field(PMIC_LDO_VRF12_OP_EN, 0x3, 0)) ? 1200000 : 0;
+}
+
+static void pmic_enable_vrf12(void)
+{
+	pwrap_write_field(PMIC_LDO_VRF12_CON0, 1, 0x3, 0);
+	pwrap_write_field(PMIC_LDO_VRF12_OP_EN, 1, 0x3, 0);
+}
+
+static u32 pmic_get_vcn33_vol(void)
+{
+	u32 ret;
+	u16 vol_reg;
+
+	vol_reg = pwrap_read_field(PMIC_VCN33_ANA_CON0, 0x3, 8);
+
+	switch (vol_reg) {
+	case 0x1:
+		ret = 3300000;
+		break;
+	case 0x2:
+		ret = 3400000;
+		break;
+	case 0x3:
+		ret = 3500000;
+		break;
+	default:
+		printk(BIOS_ERR, "ERROR[%s] VCN33 read fail: %d\n", __func__, vol_reg);
+		ret = 0;
+		break;
+	}
+	return ret;
+}
+
+static void pmic_set_vcn33_vol(u32 vcn33_uv)
+{
+	u16 val = 0;
+
+	switch (vcn33_uv) {
+	case 3300000:
+		val = 0x1;
+		break;
+	case 3400000:
+		val = 0x2;
+		break;
+	case 3500000:
+		val = 0x3;
+		break;
+	default:
+		die("ERROR[%s]: VCN33 voltage %u is not support.\n", __func__, vcn33_uv);
+		return;
+	}
+
+	pwrap_write_field(PMIC_VCN33_ANA_CON0, val, 0x3, 8);
+
+	/* Force SW to turn on */
+	pwrap_write_field(PMIC_LDO_VCN33_CON0_0, 1, 0x1, 0);
+}
+
 static void pmic_wdt_set(void)
 {
 	/* [5]=1, RG_WDTRSTB_DEB */
@@ -824,6 +886,13 @@ void mt6366_set_voltage(enum mt6366_regulator_id id, u32 voltage_uv)
 	case MT6366_VSRAM_PROC12:
 		pmic_set_vsram_proc12_vol(voltage_uv);
 		break;
+	case MT6366_VRF12:
+		/* VRF12 only provides 1.2V, so we just need to enable it */
+		pmic_enable_vrf12();
+		break;
+	case MT6366_VCN33:
+		pmic_set_vcn33_vol(voltage_uv);
+		break;
 	default:
 		printk(BIOS_ERR, "%s: PMIC %d is not supported\n", __func__, id);
 		break;
@@ -847,6 +916,10 @@ u32 mt6366_get_voltage(enum mt6366_regulator_id id)
 		return pmic_get_vproc12_vol();
 	case MT6366_VSRAM_PROC12:
 		return pmic_get_vsram_proc12_vol();
+	case MT6366_VRF12:
+		return pmic_get_vrf12_vol();
+	case MT6366_VCN33:
+		return pmic_get_vcn33_vol();
 	default:
 		printk(BIOS_ERR, "%s: PMIC %d is not supported\n", __func__, id);
 		break;