summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/qualcomm/emac/emac-mac.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/ethernet/qualcomm/emac/emac-mac.c')
-rw-r--r--drivers/net/ethernet/qualcomm/emac/emac-mac.c41
1 files changed, 27 insertions, 14 deletions
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-mac.c b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
index bcd4708b3745..9cbb27263742 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-mac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
@@ -309,22 +309,12 @@ void emac_mac_mode_config(struct emac_adapter *adpt)
/* Config descriptor rings */
static void emac_mac_dma_rings_config(struct emac_adapter *adpt)
{
- static const unsigned short tpd_q_offset[] = {
- EMAC_DESC_CTRL_8, EMAC_H1TPD_BASE_ADDR_LO,
- EMAC_H2TPD_BASE_ADDR_LO, EMAC_H3TPD_BASE_ADDR_LO};
- static const unsigned short rfd_q_offset[] = {
- EMAC_DESC_CTRL_2, EMAC_DESC_CTRL_10,
- EMAC_DESC_CTRL_12, EMAC_DESC_CTRL_13};
- static const unsigned short rrd_q_offset[] = {
- EMAC_DESC_CTRL_5, EMAC_DESC_CTRL_14,
- EMAC_DESC_CTRL_15, EMAC_DESC_CTRL_16};
-
/* TPD (Transmit Packet Descriptor) */
writel(upper_32_bits(adpt->tx_q.tpd.dma_addr),
adpt->base + EMAC_DESC_CTRL_1);
writel(lower_32_bits(adpt->tx_q.tpd.dma_addr),
- adpt->base + tpd_q_offset[0]);
+ adpt->base + EMAC_DESC_CTRL_8);
writel(adpt->tx_q.tpd.count & TPD_RING_SIZE_BMSK,
adpt->base + EMAC_DESC_CTRL_9);
@@ -334,9 +324,9 @@ static void emac_mac_dma_rings_config(struct emac_adapter *adpt)
adpt->base + EMAC_DESC_CTRL_0);
writel(lower_32_bits(adpt->rx_q.rfd.dma_addr),
- adpt->base + rfd_q_offset[0]);
+ adpt->base + EMAC_DESC_CTRL_2);
writel(lower_32_bits(adpt->rx_q.rrd.dma_addr),
- adpt->base + rrd_q_offset[0]);
+ adpt->base + EMAC_DESC_CTRL_5);
writel(adpt->rx_q.rfd.count & RFD_RING_SIZE_BMSK,
adpt->base + EMAC_DESC_CTRL_3);
@@ -551,6 +541,28 @@ static void emac_mac_start(struct emac_adapter *adpt)
mac &= ~(HUGEN | VLAN_STRIP | TPAUSE | SIMR | HUGE | MULTI_ALL |
DEBUG_MODE | SINGLE_PAUSE_MODE);
+ /* Enable single-pause-frame mode if requested.
+ *
+ * If enabled, the EMAC will send a single pause frame when the RX
+ * queue is full. This normally leads to packet loss because
+ * the pause frame disables the remote MAC only for 33ms (the quanta),
+ * and then the remote MAC continues sending packets even though
+ * the RX queue is still full.
+ *
+ * If disabled, the EMAC sends a pause frame every 31ms until the RX
+ * queue is no longer full. Normally, this is the preferred
+ * method of operation. However, when the system is hung (e.g.
+ * cores are halted), the EMAC interrupt handler is never called
+ * and so the RX queue fills up quickly and stays full. The resuling
+ * non-stop "flood" of pause frames sometimes has the effect of
+ * disabling nearby switches. In some cases, other nearby switches
+ * are also affected, shutting down the entire network.
+ *
+ * The user can enable or disable single-pause-frame mode
+ * via ethtool.
+ */
+ mac |= adpt->single_pause_mode ? SINGLE_PAUSE_MODE : 0;
+
writel_relaxed(csr1, adpt->csr + EMAC_EMAC_WRAPPER_CSR1);
writel_relaxed(mac, adpt->base + EMAC_MAC_CTRL);
@@ -876,7 +888,8 @@ static void emac_mac_rx_descs_refill(struct emac_adapter *adpt,
curr_rxbuf->dma_addr =
dma_map_single(adpt->netdev->dev.parent, skb->data,
- curr_rxbuf->length, DMA_FROM_DEVICE);
+ adpt->rxbuf_size, DMA_FROM_DEVICE);
+
ret = dma_mapping_error(adpt->netdev->dev.parent,
curr_rxbuf->dma_addr);
if (ret) {
OpenPOWER on IntegriCloud