pasemi_mac: workaround for erratum 5971

pasemi_mac: workaround for erratum 5971

Implement workarounds for erratum 5971, where L2 hints aren't considered
properly unless the way hint is enabled on the interface. Since L2 isn't
setup to dedicate a way to headers, we need to reset the packet count
by hand so it won't run out of credits.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

2 files changed, 16 insertions, 1 deletions

diff --git a/drivers/net/pasemi_mac.c b/drivers/net/pasemi_mac.c
index 5eb5e47120d0..c538c66d4b4f 100644
--- a/drivers/net/pasemi_mac.c
+++ b/drivers/net/pasemi_mac.c
@@ -239,7 +239,9 @@ static int pasemi_mac_setup_rx_resources(struct net_device *dev)
                            PAS_DMA_RXINT_BASEU_SIZ(RX_RING_SIZE >> 3));
 
         write_dma_reg(mac, PAS_DMA_RXINT_CFG(mac->dma_if),
-                           PAS_DMA_RXINT_CFG_DHL(2));
+                           PAS_DMA_RXINT_CFG_DHL(3) |
+                           PAS_DMA_RXINT_CFG_L2 |
+                           PAS_DMA_RXINT_CFG_LW);
 
         ring->next_to_fill = 0;
         ring->next_to_clean = 0;
@@ -589,6 +591,11 @@ static int pasemi_mac_clean_rx(struct pasemi_mac *mac, int limit)
                 n += 2;
         }
 
+        if (n > RX_RING_SIZE) {
+                /* Errata 5971 workaround: L2 target of headers */
+                write_iob_reg(mac, PAS_IOB_COM_PKTHDRCNT, 0);
+                n &= (RX_RING_SIZE-1);
+        }
         mac->rx->next_to_clean = n;
         pasemi_mac_replenish_rx_ring(mac->netdev, limit-count);
 
diff --git a/drivers/net/pasemi_mac.h b/drivers/net/pasemi_mac.h
index 5a896aa87a99..db3393674ae7 100644
--- a/drivers/net/pasemi_mac.h
+++ b/drivers/net/pasemi_mac.h
@@ -210,6 +210,8 @@ enum {
 #define    PAS_DMA_RXINT_CFG_DHL_S      24
 #define    PAS_DMA_RXINT_CFG_DHL(x)     (((x) << PAS_DMA_RXINT_CFG_DHL_S) & \
                                          PAS_DMA_RXINT_CFG_DHL_M)
+#define    PAS_DMA_RXINT_CFG_LW         0x00200000
+#define    PAS_DMA_RXINT_CFG_L2         0x00100000
 #define    PAS_DMA_RXINT_CFG_WIF        0x00000002
 #define    PAS_DMA_RXINT_CFG_WIL        0x00000001
 
@@ -315,6 +317,12 @@ enum {
 #define    PAS_STATUS_SOFT              0x4000000000000000ull
 #define    PAS_STATUS_INT               0x8000000000000000ull
 
+#define PAS_IOB_COM_PKTHDRCNT           0x120
+#define    PAS_IOB_COM_PKTHDRCNT_PKTHDR1_M      0x0fff0000
+#define    PAS_IOB_COM_PKTHDRCNT_PKTHDR1_S      16
+#define    PAS_IOB_COM_PKTHDRCNT_PKTHDR0_M      0x00000fff
+#define    PAS_IOB_COM_PKTHDRCNT_PKTHDR0_S      0
+
 #define PAS_IOB_DMA_RXCH_CFG(i)         (0x1100 + (i)*4)
 #define    PAS_IOB_DMA_RXCH_CFG_CNTTH_M         0x00000fff
 #define    PAS_IOB_DMA_RXCH_CFG_CNTTH_S         0