diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index 7453b17a37a2..cb47e68c1a3e 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -165,7 +165,7 @@ enum ravb_reg {
 	GTO2	= 0x03A8,
 	GIC	= 0x03AC,
 	GIS	= 0x03B0,
-	GCPT	= 0x03B4,	/* Undocumented? */
+	GCPT	= 0x03B4,	/* Documented for R-Car Gen3 only */
 	GCT0	= 0x03B8,
 	GCT1	= 0x03BC,
 	GCT2	= 0x03C0,
@@ -225,7 +225,7 @@ enum CSR_BIT {
 	CSR_OPS_RESET	= 0x00000001,
 	CSR_OPS_CONFIG	= 0x00000002,
 	CSR_OPS_OPERATION = 0x00000004,
-	CSR_OPS_STANDBY	= 0x00000008,	/* Undocumented? */
+	CSR_OPS_STANDBY	= 0x00000008,	/* Documented for R-Car Gen3 only */
 	CSR_DTS		= 0x00000100,
 	CSR_TPO0	= 0x00010000,
 	CSR_TPO1	= 0x00020000,
@@ -241,13 +241,12 @@ enum ESR_BIT {
 	ESR_EIL		= 0x00001000,
 };
 
-/* APSR */
+/* APSR (R-Car Gen3 only) */
 enum APSR_BIT {
-	APSR_MEMS		= 0x00000002,
-	APSR_CMSW		= 0x00000010,
-	APSR_DM			= 0x00006000,	/* Undocumented? */
-	APSR_DM_RDM		= 0x00002000,
-	APSR_DM_TDM		= 0x00004000,
+	APSR_MEMS	= 0x00000002,	/* Undocumented */
+	APSR_CMSW	= 0x00000010,
+	APSR_RDM	= 0x00002000,
+	APSR_TDM	= 0x00004000,
 };
 
 /* RCR */
@@ -530,16 +529,16 @@ enum RIS2_BIT {
 
 /* TIC */
 enum TIC_BIT {
-	TIC_FTE0	= 0x00000001,	/* Undocumented? */
-	TIC_FTE1	= 0x00000002,	/* Undocumented? */
+	TIC_FTE0	= 0x00000001,	/* Documented for R-Car Gen3 only */
+	TIC_FTE1	= 0x00000002,	/* Documented for R-Car Gen3 only */
 	TIC_TFUE	= 0x00000100,
 	TIC_TFWE	= 0x00000200,
 };
 
 /* TIS */
 enum TIS_BIT {
-	TIS_FTF0	= 0x00000001,	/* Undocumented? */
-	TIS_FTF1	= 0x00000002,	/* Undocumented? */
+	TIS_FTF0	= 0x00000001,	/* Documented for R-Car Gen3 only */
+	TIS_FTF1	= 0x00000002,	/* Documented for R-Car Gen3 only */
 	TIS_TFUF	= 0x00000100,
 	TIS_TFWF	= 0x00000200,
 	TIS_RESERVED	= (GENMASK(31, 20) | GENMASK(15, 12) | GENMASK(7, 4))
@@ -547,8 +546,8 @@ enum TIS_BIT {
 
 /* ISS */
 enum ISS_BIT {
-	ISS_FRS		= 0x00000001,	/* Undocumented? */
-	ISS_FTS		= 0x00000004,	/* Undocumented? */
+	ISS_FRS		= 0x00000001,	/* Documented for R-Car Gen3 only */
+	ISS_FTS		= 0x00000004,	/* Documented for R-Car Gen3 only */
 	ISS_ES		= 0x00000040,
 	ISS_MS		= 0x00000080,
 	ISS_TFUS	= 0x00000100,
@@ -608,13 +607,13 @@ enum GTI_BIT {
 
 /* GIC */
 enum GIC_BIT {
-	GIC_PTCE	= 0x00000001,	/* Undocumented? */
+	GIC_PTCE	= 0x00000001,	/* Documented for R-Car Gen3 only */
 	GIC_PTME	= 0x00000004,
 };
 
 /* GIS */
 enum GIS_BIT {
-	GIS_PTCF	= 0x00000001,	/* Undocumented? */
+	GIS_PTCF	= 0x00000001,	/* Documented for R-Car Gen3 only */
 	GIS_PTMF	= 0x00000004,
 	GIS_RESERVED	= GENMASK(15, 10),
 };
@@ -808,10 +807,10 @@ enum ECMR_BIT {
 	ECMR_TE		= 0x00000020,
 	ECMR_RE		= 0x00000040,
 	ECMR_MPDE	= 0x00000200,
-	ECMR_TXF	= 0x00010000,	/* Undocumented? */
+	ECMR_TXF	= 0x00010000,	/* Documented for R-Car Gen3 only */
 	ECMR_RXF	= 0x00020000,
 	ECMR_PFR	= 0x00040000,
-	ECMR_ZPF	= 0x00080000,	/* Undocumented? */
+	ECMR_ZPF	= 0x00080000,	/* Documented for R-Car Gen3 only */
 	ECMR_RZPF	= 0x00100000,
 	ECMR_DPAD	= 0x00200000,
 	ECMR_RCSC	= 0x00800000,
@@ -830,7 +829,7 @@ enum ECSR_BIT {
 enum ECSIPR_BIT {
 	ECSIPR_ICDIP	= 0x00000001,
 	ECSIPR_MPDIP	= 0x00000002,
-	ECSIPR_LCHNGIP	= 0x00000004,	/* Undocumented? */
+	ECSIPR_LCHNGIP	= 0x00000004,
 };
 
 /* PIR */
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index bd30505fbc57..eb0c03bdb12d 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2034,10 +2034,10 @@ static void ravb_set_delay_mode(struct net_device *ndev)
 	u32 set = 0;
 
 	if (priv->rxcidm)
-		set |= APSR_DM_RDM;
+		set |= APSR_RDM;
 	if (priv->txcidm)
-		set |= APSR_DM_TDM;
-	ravb_modify(ndev, APSR, APSR_DM, set);
+		set |= APSR_TDM;
+	ravb_modify(ndev, APSR, APSR_RDM | APSR_TDM, set);
 }
 
 static int ravb_probe(struct platform_device *pdev)