[PATCH net-next 2/6] tg3: Make the TX BD DMA limit configurable
From: Matt Carlson <hidden>
Date: 2011-12-14 21:09:50
Subsystem:
broadcom tg3 gigabit ethernet driver, networking drivers, the rest · Maintainers:
Pavan Chebbi, Michael Chan, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
The 57766 ASIC rev will impose a new TX BD DMA limit on the driver. This patch prepares for 57766 support by making the tx BD DMA limit tunable. Signed-off-by: Matt Carlson <redacted> Reviewed-by: Michael Chan <mchan@broadcom.com> Reviewed-by: Benjamin Li <redacted> --- drivers/net/ethernet/broadcom/tg3.c | 16 ++++++++-------- drivers/net/ethernet/broadcom/tg3.h | 1 + 2 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 8a6ea19..9c9a4b4 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c@@ -199,7 +199,7 @@ static inline void _tg3_flag_clear(enum TG3_FLAGS flag, unsigned long *bits) /* 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_TX_BD_DMA_MAX_4K 4096 #define TG3_RAW_IP_ALIGN 2
@@ -6449,17 +6449,17 @@ static bool tg3_tx_frag_set(struct tg3_napi *tnapi, u32 *entry, u32 *budget, if (tg3_40bit_overflow_test(tp, map, len)) hwbug = 1; - if (tg3_flag(tp, 4K_FIFO_LIMIT)) { + if (tp->dma_limit) { u32 prvidx = *entry; u32 tmp_flag = flags & ~TXD_FLAG_END; - while (len > TG3_TX_BD_DMA_MAX && *budget) { - u32 frag_len = TG3_TX_BD_DMA_MAX; - len -= TG3_TX_BD_DMA_MAX; + while (len > tp->dma_limit && *budget) { + u32 frag_len = tp->dma_limit; + len -= tp->dma_limit; /* Avoid the 8byte DMA problem */ if (len <= 8) { - len += TG3_TX_BD_DMA_MAX / 2; - frag_len = TG3_TX_BD_DMA_MAX / 2; + len += tp->dma_limit / 2; + frag_len = tp->dma_limit / 2; } tnapi->tx_buffers[*entry].fragmented = true;
@@ -14041,7 +14041,7 @@ static int __devinit tg3_get_invariants(struct tg3 *tp) 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); + tp->dma_limit = TG3_TX_BD_DMA_MAX_4K; if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5717 || GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5719 ||
diff --git a/drivers/net/ethernet/broadcom/tg3.h b/drivers/net/ethernet/broadcom/tg3.h
index 9d9f634..2ba5be1 100644
--- a/drivers/net/ethernet/broadcom/tg3.h
+++ b/drivers/net/ethernet/broadcom/tg3.h@@ -2994,6 +2994,7 @@ struct tg3 { /* begin "tx thread" cacheline section */ void (*write32_tx_mbox) (struct tg3 *, u32, u32); + u32 dma_limit; /* begin "rx thread" cacheline section */ struct tg3_napi napi[TG3_IRQ_MAX_VECS];
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1.7.3.4