R-Car AVB-DMAC has Maximum 2K size on RZ buffer.
We need to Allow for changing the MTU within the
limit of the maximum size of a descriptor (2048 bytes).
Add a rx_2k_buffers hw feature bit to struct ravb_hw_info
to add this constraint only for R-Car.
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/renesas/ravb.h | 1 +
drivers/net/ethernet/renesas/ravb_main.c | 8 ++++++--
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index 7532cb51d7b8..ab4909244276 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -1033,6 +1033,7 @@ struct ravb_hw_info {
unsigned magic_pkt:1; /* E-MAC supports magic packet detection */
unsigned mii_rgmii_selection:1; /* E-MAC supports mii/rgmii selection */
unsigned half_duplex:1; /* E-MAC supports half duplex mode */
+ unsigned rx_2k_buffers:1; /* AVB-DMAC has Max 2K buf size on RX */
};
struct ravb_private {
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 7f06adbd00e1..9c0d35f4b221 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2164,6 +2164,7 @@ static const struct ravb_hw_info ravb_gen3_hw_info = {
.ccc_gac = 1,
.multi_tsrq = 1,
.magic_pkt = 1,
+ .rx_2k_buffers = 1,
};
static const struct ravb_hw_info ravb_gen2_hw_info = {
@@ -2184,6 +2185,7 @@ static const struct ravb_hw_info ravb_gen2_hw_info = {
.aligned_tx = 1,
.multi_tsrq = 1,
.magic_pkt = 1,
+ .rx_2k_buffers = 1,
};
static const struct ravb_hw_info rgeth_hw_info = {
@@ -2417,8 +2419,10 @@ static int ravb_probe(struct platform_device *pdev)
}
clk_prepare_enable(priv->refclk);
- ndev->max_mtu = 2048 - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN);
- ndev->min_mtu = ETH_MIN_MTU;
+ if (info->rx_2k_buffers) {
+ ndev->max_mtu = 2048 - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN);
+ ndev->min_mtu = ETH_MIN_MTU;
+ }
/* FIXME: R-Car Gen2 has 4byte alignment restriction for tx buffer
* Use two descriptor to handle such situation. First descriptor to
--
2.17.1
