net: fec: don't dump RX FIFO register when not available

Commit db65f35 ("net: fec: add support of ethtool get_regs") introduce ethool "--register-dump" interface to dump all FEC registers. But not all silicon implementations of the Freescale FEC hardware module have the FRBR (FIFO Receive Bound Register) and FRSR (FIFO Receive Start Register) register, so we should not be trying to dump them on those that don't. To fix it we create a quirk flag, FEC_QUIRK_HAS_RFREG, and check it before dump those RX FIFO registers. Signed-off-by: Fugang Duan <[email protected]> Signed-off-by: David S. Miller <[email protected]>
akeromi · Oct 16, 2018 · ec20a63 · ec20a63
1 parent fbe1222
commit ec20a63
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Showing 2 changed files with 16 additions and 4 deletions.
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
@@ -452,6 +452,10 @@ struct bufdesc_ex {
  * initialisation.
  */
 #define FEC_QUIRK_MIB_CLEAR		(1 << 15)
+/* Only i.MX25/i.MX27/i.MX28 controller supports FRBR,FRSR registers,
+ * those FIFO receive registers are resolved in other platforms.
+ */
+#define FEC_QUIRK_HAS_FRREG		(1 << 16)
 
 struct bufdesc_prop {
 	int qid;

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
@@ -91,14 +91,16 @@ static struct platform_device_id fec_devtype[] = {
 		.driver_data = 0,
 	}, {
 		.name = "imx25-fec",
-		.driver_data = FEC_QUIRK_USE_GASKET | FEC_QUIRK_MIB_CLEAR,
+		.driver_data = FEC_QUIRK_USE_GASKET | FEC_QUIRK_MIB_CLEAR |
+			       FEC_QUIRK_HAS_FRREG,
 	}, {
 		.name = "imx27-fec",
-		.driver_data = FEC_QUIRK_MIB_CLEAR,
+		.driver_data = FEC_QUIRK_MIB_CLEAR | FEC_QUIRK_HAS_FRREG,
 	}, {
 		.name = "imx28-fec",
 		.driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME |
-				FEC_QUIRK_SINGLE_MDIO | FEC_QUIRK_HAS_RACC,
+				FEC_QUIRK_SINGLE_MDIO | FEC_QUIRK_HAS_RACC |
+				FEC_QUIRK_HAS_FRREG,
 	}, {
 		.name = "imx6q-fec",
 		.driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
@@ -2164,7 +2166,13 @@ static void fec_enet_get_regs(struct net_device *ndev,
 	memset(buf, 0, regs->len);
 
 	for (i = 0; i < ARRAY_SIZE(fec_enet_register_offset); i++) {
-		off = fec_enet_register_offset[i] / 4;
+		off = fec_enet_register_offset[i];
+
+		if ((off == FEC_R_BOUND || off == FEC_R_FSTART) &&
+		    !(fep->quirks & FEC_QUIRK_HAS_FRREG))
+			continue;
+
+		off >>= 2;
 		buf[off] = readl(&theregs[off]);
 	}
 }