net: dwc_eth_qos: Fully rewrite RX descriptor field 3

The RX descriptor field 3 should contain only OWN and BUF1V bits before
being used for receiving data by the DMA engine. However, right now, if
the descriptor was already used for receiving data and is being cleared,
the field 3 is only modified and the aforementioned two bits are ORRed
into the field. This could lead to a residual dirty bits being left in
the field 3 from previous transfer, and it generally does. Fully set the
field 3 instead to clear those residual dirty bits.

Reviewed-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: Ramon Fried <rfried.dev@gmail.com>
Cc: Stephen Warren <swarren@nvidia.com>
This commit is contained in:
Marek Vasut 2020-03-23 02:02:57 +01:00 committed by marex
parent c2abfca9be
commit 4332d80617

View File

@ -1288,7 +1288,7 @@ static int eqos_start(struct udevice *dev)
struct eqos_desc *rx_desc = &(eqos->rx_descs[i]);
rx_desc->des0 = (u32)(ulong)(eqos->rx_dma_buf +
(i * EQOS_MAX_PACKET_SIZE));
rx_desc->des3 |= EQOS_DESC3_OWN | EQOS_DESC3_BUF1V;
rx_desc->des3 = EQOS_DESC3_OWN | EQOS_DESC3_BUF1V;
}
eqos->config->ops->eqos_flush_desc(eqos->descs);
@ -1482,7 +1482,7 @@ static int eqos_free_pkt(struct udevice *dev, uchar *packet, int length)
* writes to the rest of the descriptor too.
*/
mb();
rx_desc->des3 |= EQOS_DESC3_OWN | EQOS_DESC3_BUF1V;
rx_desc->des3 = EQOS_DESC3_OWN | EQOS_DESC3_BUF1V;
eqos->config->ops->eqos_flush_desc(rx_desc);
writel((ulong)rx_desc, &eqos->dma_regs->ch0_rxdesc_tail_pointer);