tg3: Add New 5719 Read DMA workaround

commit 091f0ea30074bc43f9250961b3247af713024bc6 upstream.

After Power-on-reset, the 5719's TX DMA length registers may contain
uninitialized values and cause TX DMA to stall.  Check for invalid
values and set a register bit to flush the TX channels.  The bit
needs to be turned off after the DMA channels have been flushed.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index ec13a59..26215f1 100644 (file)
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -8920,6 +8920,19 @@ static int tg3_reset_hw(struct tg3 *tp, int reset_phy)
        tw32_f(RDMAC_MODE, rdmac_mode);
        udelay(40);
 
+       if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5719) {
+               for (i = 0; i < TG3_NUM_RDMA_CHANNELS; i++) {
+                       if (tr32(TG3_RDMA_LENGTH + (i << 2)) > TG3_MAX_MTU(tp))
+                               break;
+               }
+               if (i < TG3_NUM_RDMA_CHANNELS) {
+                       val = tr32(TG3_LSO_RD_DMA_CRPTEN_CTRL);
+                       val |= TG3_LSO_RD_DMA_TX_LENGTH_WA;
+                       tw32(TG3_LSO_RD_DMA_CRPTEN_CTRL, val);
+                       tg3_flag_set(tp, 5719_RDMA_BUG);
+               }
+       }
+
        tw32(RCVDCC_MODE, RCVDCC_MODE_ENABLE | RCVDCC_MODE_ATTN_ENABLE);
        if (!tg3_flag(tp, 5705_PLUS))
                tw32(MBFREE_MODE, MBFREE_MODE_ENABLE);
@@ -9200,6 +9213,16 @@ static void tg3_periodic_fetch_stats(struct tg3 *tp)
        TG3_STAT_ADD32(&sp->tx_ucast_packets, MAC_TX_STATS_UCAST);
        TG3_STAT_ADD32(&sp->tx_mcast_packets, MAC_TX_STATS_MCAST);
        TG3_STAT_ADD32(&sp->tx_bcast_packets, MAC_TX_STATS_BCAST);
+       if (unlikely(tg3_flag(tp, 5719_RDMA_BUG) &&
+                    (sp->tx_ucast_packets.low + sp->tx_mcast_packets.low +
+                     sp->tx_bcast_packets.low) > TG3_NUM_RDMA_CHANNELS)) {
+               u32 val;
+
+               val = tr32(TG3_LSO_RD_DMA_CRPTEN_CTRL);
+               val &= ~TG3_LSO_RD_DMA_TX_LENGTH_WA;
+               tw32(TG3_LSO_RD_DMA_CRPTEN_CTRL, val);
+               tg3_flag_clear(tp, 5719_RDMA_BUG);
+       }
 
        TG3_STAT_ADD32(&sp->rx_octets, MAC_RX_STATS_OCTETS);
        TG3_STAT_ADD32(&sp->rx_fragments, MAC_RX_STATS_FRAGMENTS);

diff --git a/drivers/net/ethernet/broadcom/tg3.h b/drivers/net/ethernet/broadcom/tg3.h
index 94b4bd0..53c617a 100644 (file)
--- a/drivers/net/ethernet/broadcom/tg3.h
+++ b/drivers/net/ethernet/broadcom/tg3.h
@@ -1368,7 +1368,11 @@
 #define TG3_LSO_RD_DMA_CRPTEN_CTRL     0x00004910
 #define TG3_LSO_RD_DMA_CRPTEN_CTRL_BLEN_BD_4K   0x00030000
 #define TG3_LSO_RD_DMA_CRPTEN_CTRL_BLEN_LSO_4K  0x000c0000
-/* 0x4914 --> 0x4c00 unused */
+#define TG3_LSO_RD_DMA_TX_LENGTH_WA     0x02000000
+/* 0x4914 --> 0x4be0 unused */
+
+#define TG3_NUM_RDMA_CHANNELS          4
+#define TG3_RDMA_LENGTH                        0x00004be0
 
 /* Write DMA control registers */
 #define WDMAC_MODE                     0x00004c00
@@ -2921,6 +2925,7 @@ enum TG3_FLAGS {
        TG3_FLAG_APE_HAS_NCSI,
        TG3_FLAG_5717_PLUS,
        TG3_FLAG_4K_FIFO_LIMIT,
+       TG3_FLAG_5719_RDMA_BUG,
        TG3_FLAG_RESET_TASK_PENDING,
 
        /* Add new flags before this comment and TG3_FLAG_NUMBER_OF_FLAGS */