net/e1000: fix i219 hang on reset/close

Unit hang may occur if multiple descriptors are available in the rings
during reset or close. This state can be detected by configure status
by bit 8 in register. If the bit is set and there are pending
descriptors in one of the rings, we must flush them before reset or
close.

Fixes: 805803445a02 ("e1000: support EM devices (also known as e1000/e1000e)")
Cc: stable@dpdk.org
Signed-off-by: Xiao Zhang <xiao.zhang@intel.com>
Reviewed-by: Xiaolong Ye <xiaolong.ye@intel.com>

diff --git a/drivers/net/e1000/e1000_ethdev.h b/drivers/net/e1000/e1000_ethdev.h
index 67acb73..01ff943 100644 (file)
--- a/drivers/net/e1000/e1000_ethdev.h
+++ b/drivers/net/e1000/e1000_ethdev.h
@@ -35,6 +35,9 @@
 #define IGB_MAX_RX_QUEUE_NUM           8
 #define IGB_MAX_RX_QUEUE_NUM_82576     16
 
+#define E1000_I219_MAX_RX_QUEUE_NUM            2
+#define E1000_I219_MAX_TX_QUEUE_NUM            2
+
 #define E1000_SYN_FILTER_ENABLE        0x00000001 /* syn filter enable field */
 #define E1000_SYN_FILTER_QUEUE         0x0000000E /* syn filter queue field */
 #define E1000_SYN_FILTER_QUEUE_SHIFT   1          /* syn filter queue field */
@@ -522,5 +525,6 @@ int igb_action_rss_same(const struct rte_flow_action_rss *comp,
 int igb_config_rss_filter(struct rte_eth_dev *dev,
                        struct igb_rte_flow_rss_conf *conf,
                        bool add);
+void em_flush_desc_rings(struct rte_eth_dev *dev);
 
 #endif /* _E1000_ETHDEV_H_ */

diff --git a/drivers/net/e1000/em_ethdev.c b/drivers/net/e1000/em_ethdev.c
index fc01378..20b5406 100644 (file)
--- a/drivers/net/e1000/em_ethdev.c
+++ b/drivers/net/e1000/em_ethdev.c
@@ -737,6 +737,11 @@ eth_em_stop(struct rte_eth_dev *dev)
        em_lsc_intr_disable(hw);
 
        e1000_reset_hw(hw);
+
+       /* Flush desc rings for i219 */
+       if (hw->mac.type >= e1000_pch_spt)
+               em_flush_desc_rings(dev);
+
        if (hw->mac.type >= e1000_82544)
                E1000_WRITE_REG(hw, E1000_WUC, 0);
 

diff --git a/drivers/net/e1000/em_rxtx.c b/drivers/net/e1000/em_rxtx.c
index 9d7cbc4..6f40b45 100644 (file)
--- a/drivers/net/e1000/em_rxtx.c
+++ b/drivers/net/e1000/em_rxtx.c
@@ -18,6 +18,7 @@
 #include <rte_log.h>
 #include <rte_debug.h>
 #include <rte_pci.h>
+#include <rte_bus_pci.h>
 #include <rte_memory.h>
 #include <rte_memcpy.h>
 #include <rte_memzone.h>
@@ -59,6 +60,11 @@
 #define E1000_TX_OFFLOAD_NOTSUP_MASK \
                (PKT_TX_OFFLOAD_MASK ^ E1000_TX_OFFLOAD_MASK)
 
+/* PCI offset for querying configuration status register */
+#define PCI_CFG_STATUS_REG                 0x06
+#define FLUSH_DESC_REQUIRED               0x100
+
+
 /**
  * Structure associated with each descriptor of the RX ring of a RX queue.
  */
@@ -2016,3 +2022,108 @@ em_txq_info_get(struct rte_eth_dev *dev, uint16_t queue_id,
        qinfo->conf.tx_rs_thresh = txq->tx_rs_thresh;
        qinfo->conf.offloads = txq->offloads;
 }
+
+static void
+e1000_flush_tx_ring(struct rte_eth_dev *dev)
+{
+       struct e1000_hw *hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+       volatile struct e1000_data_desc *tx_desc;
+       volatile uint32_t *tdt_reg_addr;
+       uint32_t tdt, tctl, txd_lower = E1000_TXD_CMD_IFCS;
+       uint16_t size = 512;
+       struct em_tx_queue *txq;
+       int i;
+
+       if (dev->data->tx_queues == NULL)
+               return;
+       tctl = E1000_READ_REG(hw, E1000_TCTL);
+       E1000_WRITE_REG(hw, E1000_TCTL, tctl | E1000_TCTL_EN);
+       for (i = 0; i < dev->data->nb_tx_queues &&
+               i < E1000_I219_MAX_TX_QUEUE_NUM; i++) {
+               txq = dev->data->tx_queues[i];
+               tdt = E1000_READ_REG(hw, E1000_TDT(i));
+               if (tdt != txq->tx_tail)
+                       return;
+               tx_desc = &txq->tx_ring[txq->tx_tail];
+               tx_desc->buffer_addr = rte_cpu_to_le_64(txq->tx_ring_phys_addr);
+               tx_desc->lower.data = rte_cpu_to_le_32(txd_lower | size);
+               tx_desc->upper.data = 0;
+
+               rte_wmb();
+               txq->tx_tail++;
+               if (txq->tx_tail == txq->nb_tx_desc)
+                       txq->tx_tail = 0;
+               rte_io_wmb();
+               tdt_reg_addr = E1000_PCI_REG_ADDR(hw, E1000_TDT(i));
+               E1000_PCI_REG_WRITE_RELAXED(tdt_reg_addr, txq->tx_tail);
+               usec_delay(250);
+       }
+}
+
+static void
+e1000_flush_rx_ring(struct rte_eth_dev *dev)
+{
+       uint32_t rctl, rxdctl;
+       struct e1000_hw *hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+       int i;
+
+       rctl = E1000_READ_REG(hw, E1000_RCTL);
+       E1000_WRITE_REG(hw, E1000_RCTL, rctl & ~E1000_RCTL_EN);
+       E1000_WRITE_FLUSH(hw);
+       usec_delay(150);
+
+       for (i = 0; i < dev->data->nb_rx_queues &&
+               i < E1000_I219_MAX_RX_QUEUE_NUM; i++) {
+               rxdctl = E1000_READ_REG(hw, E1000_RXDCTL(i));
+               /* zero the lower 14 bits (prefetch and host thresholds) */
+               rxdctl &= 0xffffc000;
+
+               /* update thresholds: prefetch threshold to 31,
+                * host threshold to 1 and make sure the granularity
+                * is "descriptors" and not "cache lines"
+                */
+               rxdctl |= (0x1F | (1UL << 8) | E1000_RXDCTL_THRESH_UNIT_DESC);
+
+               E1000_WRITE_REG(hw, E1000_RXDCTL(i), rxdctl);
+       }
+       /* momentarily enable the RX ring for the changes to take effect */
+       E1000_WRITE_REG(hw, E1000_RCTL, rctl | E1000_RCTL_EN);
+       E1000_WRITE_FLUSH(hw);
+       usec_delay(150);
+       E1000_WRITE_REG(hw, E1000_RCTL, rctl & ~E1000_RCTL_EN);
+}
+
+/**
+ * em_flush_desc_rings - remove all descriptors from the descriptor rings
+ *
+ * In i219, the descriptor rings must be emptied before resetting/closing the
+ * HW. Failure to do this will cause the HW to enter a unit hang state which
+ * can only be released by PCI reset on the device
+ *
+ */
+
+void
+em_flush_desc_rings(struct rte_eth_dev *dev)
+{
+       uint32_t fextnvm11, tdlen;
+       struct e1000_hw *hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+       struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev);
+       uint16_t pci_cfg_status = 0;
+
+       fextnvm11 = E1000_READ_REG(hw, E1000_FEXTNVM11);
+       E1000_WRITE_REG(hw, E1000_FEXTNVM11,
+                       fextnvm11 | E1000_FEXTNVM11_DISABLE_MULR_FIX);
+       tdlen = E1000_READ_REG(hw, E1000_TDLEN(0));
+       rte_pci_read_config(pci_dev, &pci_cfg_status, sizeof(pci_cfg_status),
+                               PCI_CFG_STATUS_REG);
+
+       /* do nothing if we're not in faulty state, or if the queue is empty */
+       if ((pci_cfg_status & FLUSH_DESC_REQUIRED) && tdlen) {
+               /* flush desc ring */
+               e1000_flush_tx_ring(dev);
+               rte_pci_read_config(pci_dev, &pci_cfg_status,
+                               sizeof(pci_cfg_status), PCI_CFG_STATUS_REG);
+               if (pci_cfg_status & FLUSH_DESC_REQUIRED)
+                       e1000_flush_rx_ring(dev);
+       }
+}