tg3: Break larger frags into 4k chunks for 5719
The 5719 has bug where RDMAs larger than 4k can cause problems. This
patch works around the problem by dividing larger DMA requests into
something the hardware can handle.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index b93ba3d..c77a39d 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -190,6 +190,7 @@
/* minimum number of free TX descriptors required to wake up TX process */
#define TG3_TX_WAKEUP_THRESH(tnapi) ((tnapi)->tx_pending / 4)
+#define TG3_TX_BD_DMA_MAX 4096
#define TG3_RAW_IP_ALIGN 2
@@ -5940,14 +5941,50 @@
if (tg3_40bit_overflow_test(tp, map, len))
hwbug = 1;
- if (*budget) {
+ if (tg3_flag(tp, 4K_FIFO_LIMIT)) {
+ u32 tmp_flag = flags & ~TXD_FLAG_END;
+ while (len > TG3_TX_BD_DMA_MAX) {
+ u32 frag_len = TG3_TX_BD_DMA_MAX;
+ len -= TG3_TX_BD_DMA_MAX;
+
+ if (len) {
+ tnapi->tx_buffers[*entry].fragmented = true;
+ /* Avoid the 8byte DMA problem */
+ if (len <= 8) {
+ len += TG3_TX_BD_DMA_MAX / 2;
+ frag_len = TG3_TX_BD_DMA_MAX / 2;
+ }
+ } else
+ tmp_flag = flags;
+
+ if (*budget) {
+ tg3_tx_set_bd(&tnapi->tx_ring[*entry], map,
+ frag_len, tmp_flag, mss, vlan);
+ (*budget)--;
+ *entry = NEXT_TX(*entry);
+ } else {
+ hwbug = 1;
+ break;
+ }
+
+ map += frag_len;
+ }
+
+ if (len) {
+ if (*budget) {
+ tg3_tx_set_bd(&tnapi->tx_ring[*entry], map,
+ len, flags, mss, vlan);
+ (*budget)--;
+ *entry = NEXT_TX(*entry);
+ } else {
+ hwbug = 1;
+ }
+ }
+ } else {
tg3_tx_set_bd(&tnapi->tx_ring[*entry], map,
len, flags, mss, vlan);
- (*budget)--;
- } else
- hwbug = 1;
-
- *entry = NEXT_TX(*entry);
+ *entry = NEXT_TX(*entry);
+ }
return hwbug;
}
@@ -13899,6 +13936,9 @@
if (tg3_flag(tp, 5755_PLUS))
tg3_flag_set(tp, SHORT_DMA_BUG);
+ if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5719)
+ tg3_flag_set(tp, 4K_FIFO_LIMIT);
+
if (tg3_flag(tp, 5717_PLUS))
tg3_flag_set(tp, LRG_PROD_RING_CAP);
diff --git a/drivers/net/tg3.h b/drivers/net/tg3.h
index 466dd7a..2ea456d 100644
--- a/drivers/net/tg3.h
+++ b/drivers/net/tg3.h
@@ -2905,6 +2905,7 @@
TG3_FLAG_57765_PLUS,
TG3_FLAG_APE_HAS_NCSI,
TG3_FLAG_5717_PLUS,
+ TG3_FLAG_4K_FIFO_LIMIT,
/* Add new flags before this comment and TG3_FLAG_NUMBER_OF_FLAGS */
TG3_FLAG_NUMBER_OF_FLAGS, /* Last entry in enum TG3_FLAGS */