+ /* Distribute the fifo equally amongst the queues */
+ for (i = 0; i < queue_count; i++)
+ fifo[i] = p_fifo;
+}
+
+static unsigned int xgbe_set_nonprio_fifos(unsigned int fifo_size,
+ unsigned int queue_count,
+ unsigned int *fifo)
+{
+ unsigned int i;
+
+ BUILD_BUG_ON_NOT_POWER_OF_2(XGMAC_FIFO_MIN_ALLOC);
+
+ if (queue_count <= IEEE_8021QAZ_MAX_TCS)
+ return fifo_size;
+
+ /* Rx queues 9 and up are for specialized packets,
+ * such as PTP or DCB control packets, etc. and
+ * don't require a large fifo
+ */
+ for (i = IEEE_8021QAZ_MAX_TCS; i < queue_count; i++) {
+ fifo[i] = (XGMAC_FIFO_MIN_ALLOC / XGMAC_FIFO_UNIT) - 1;
+ fifo_size -= XGMAC_FIFO_MIN_ALLOC;
+ }
+
+ return fifo_size;
+}
+
+static unsigned int xgbe_get_pfc_delay(struct xgbe_prv_data *pdata)
+{
+ unsigned int delay;
+
+ /* If a delay has been provided, use that */
+ if (pdata->pfc->delay)
+ return pdata->pfc->delay / 8;
+
+ /* Allow for two maximum size frames */
+ delay = xgbe_get_max_frame(pdata);
+ delay += XGMAC_ETH_PREAMBLE;
+ delay *= 2;
+
+ /* Allow for PFC frame */
+ delay += XGMAC_PFC_DATA_LEN;
+ delay += ETH_HLEN + ETH_FCS_LEN;
+ delay += XGMAC_ETH_PREAMBLE;
+
+ /* Allow for miscellaneous delays (LPI exit, cable, etc.) */
+ delay += XGMAC_PFC_DELAYS;
+
+ return delay;
+}
+
+static unsigned int xgbe_get_pfc_queues(struct xgbe_prv_data *pdata)
+{
+ unsigned int count, prio_queues;
+ unsigned int i;
+
+ if (!pdata->pfc->pfc_en)
+ return 0;
+
+ count = 0;
+ prio_queues = XGMAC_PRIO_QUEUES(pdata->rx_q_count);
+ for (i = 0; i < prio_queues; i++) {
+ if (!xgbe_is_pfc_queue(pdata, i))
+ continue;
+
+ pdata->pfcq[i] = 1;
+ count++;
+ }
+
+ return count;
+}
+
+static void xgbe_calculate_dcb_fifo(struct xgbe_prv_data *pdata,
+ unsigned int fifo_size,
+ unsigned int *fifo)
+{
+ unsigned int q_fifo_size, rem_fifo, addn_fifo;
+ unsigned int prio_queues;
+ unsigned int pfc_count;
+ unsigned int i;
+
+ q_fifo_size = XGMAC_FIFO_ALIGN(xgbe_get_max_frame(pdata));
+ prio_queues = XGMAC_PRIO_QUEUES(pdata->rx_q_count);
+ pfc_count = xgbe_get_pfc_queues(pdata);
+
+ if (!pfc_count || ((q_fifo_size * prio_queues) > fifo_size)) {
+ /* No traffic classes with PFC enabled or can't do lossless */
+ xgbe_calculate_equal_fifo(fifo_size, prio_queues, fifo);
+ return;
+ }
+
+ /* Calculate how much fifo we have to play with */
+ rem_fifo = fifo_size - (q_fifo_size * prio_queues);
+
+ /* Calculate how much more than base fifo PFC needs, which also
+ * becomes the threshold activation point (RFA)
+ */
+ pdata->pfc_rfa = xgbe_get_pfc_delay(pdata);
+ pdata->pfc_rfa = XGMAC_FLOW_CONTROL_ALIGN(pdata->pfc_rfa);
+
+ if (pdata->pfc_rfa > q_fifo_size) {
+ addn_fifo = pdata->pfc_rfa - q_fifo_size;
+ addn_fifo = XGMAC_FIFO_ALIGN(addn_fifo);
+ } else {
+ addn_fifo = 0;
+ }
+
+ /* Calculate DCB fifo settings:
+ * - distribute remaining fifo between the VLAN priority
+ * queues based on traffic class PFC enablement and overall
+ * priority (0 is lowest priority, so start at highest)
+ */
+ i = prio_queues;
+ while (i > 0) {
+ i--;
+
+ fifo[i] = (q_fifo_size / XGMAC_FIFO_UNIT) - 1;
+
+ if (!pdata->pfcq[i] || !addn_fifo)
+ continue;
+
+ if (addn_fifo > rem_fifo) {
+ netdev_warn(pdata->netdev,
+ "RXq%u cannot set needed fifo size\n", i);
+ if (!rem_fifo)
+ continue;
+
+ addn_fifo = rem_fifo;
+ }
+
+ fifo[i] += (addn_fifo / XGMAC_FIFO_UNIT);
+ rem_fifo -= addn_fifo;
+ }
+
+ if (rem_fifo) {
+ unsigned int inc_fifo = rem_fifo / prio_queues;
+
+ /* Distribute remaining fifo across queues */
+ for (i = 0; i < prio_queues; i++)
+ fifo[i] += (inc_fifo / XGMAC_FIFO_UNIT);
+ }