[PATCH 3.4 118/134] tg3: Add New 5719 Read DMA workaround

From: Greg Kroah-Hartman
Date: Wed Apr 09 2014 - 23:40:00 EST


3.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Michael Chan <mchan@xxxxxxxxxxxx>

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@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Cc: Qiang Huang <h.huangqiang@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/ethernet/broadcom/tg3.c | 23 +++++++++++++++++++++++
drivers/net/ethernet/broadcom/tg3.h | 7 ++++++-
2 files changed, 29 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -9161,6 +9161,19 @@ static int tg3_reset_hw(struct tg3 *tp,
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);
@@ -9416,6 +9429,16 @@ static void tg3_periodic_fetch_stats(str
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);
--- a/drivers/net/ethernet/broadcom/tg3.h
+++ b/drivers/net/ethernet/broadcom/tg3.h
@@ -1376,7 +1376,11 @@
#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
@@ -2924,6 +2928,7 @@ enum TG3_FLAGS {
TG3_FLAG_L1PLLPD_EN,
TG3_FLAG_APE_HAS_NCSI,
TG3_FLAG_4K_FIFO_LIMIT,
+ TG3_FLAG_5719_RDMA_BUG,
TG3_FLAG_RESET_TASK_PENDING,
TG3_FLAG_5705_PLUS,
TG3_FLAG_IS_5788,


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