diff options
Diffstat (limited to 'target/linux/brcm47xx/patches-3.10/712-bgmac_implement_unaligned_addressing.patch')
| -rw-r--r-- | target/linux/brcm47xx/patches-3.10/712-bgmac_implement_unaligned_addressing.patch | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/target/linux/brcm47xx/patches-3.10/712-bgmac_implement_unaligned_addressing.patch b/target/linux/brcm47xx/patches-3.10/712-bgmac_implement_unaligned_addressing.patch new file mode 100644 index 0000000000..939ae114bb --- /dev/null +++ b/target/linux/brcm47xx/patches-3.10/712-bgmac_implement_unaligned_addressing.patch @@ -0,0 +1,140 @@ +bgmac: implement unaligned addressing for DMA rings that support it + +This is important patch for new devices that support unaligned +addressing. That devices suffer from the backward-compatibility bug in +DMA engine. In theory we should be able to use old mechanism, but in +practice DMA address seems to be randomly copied into status register +when hardware reaches end of a ring. This breaks reading slot number +from status register and we can't use DMA anymore. + +Signed-off-by: Rafał Miłecki <zajec5@gmail.com> + +--- a/drivers/net/ethernet/broadcom/bgmac.c ++++ b/drivers/net/ethernet/broadcom/bgmac.c +@@ -157,6 +157,7 @@ static netdev_tx_t bgmac_dma_tx_add(stru + if (++ring->end >= BGMAC_TX_RING_SLOTS) + ring->end = 0; + bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_TX_INDEX, ++ ring->index_base + + ring->end * sizeof(struct bgmac_dma_desc)); + + /* Always keep one slot free to allow detecting bugged calls. */ +@@ -181,6 +182,8 @@ static void bgmac_dma_tx_free(struct bgm + /* The last slot that hardware didn't consume yet */ + empty_slot = bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_TX_STATUS); + empty_slot &= BGMAC_DMA_TX_STATDPTR; ++ empty_slot -= ring->index_base; ++ empty_slot &= BGMAC_DMA_TX_STATDPTR; + empty_slot /= sizeof(struct bgmac_dma_desc); + + while (ring->start != empty_slot) { +@@ -274,6 +277,8 @@ static int bgmac_dma_rx_read(struct bgma + + end_slot = bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_STATUS); + end_slot &= BGMAC_DMA_RX_STATDPTR; ++ end_slot -= ring->index_base; ++ end_slot &= BGMAC_DMA_RX_STATDPTR; + end_slot /= sizeof(struct bgmac_dma_desc); + + ring->end = end_slot; +@@ -418,9 +423,6 @@ static int bgmac_dma_alloc(struct bgmac + ring = &bgmac->tx_ring[i]; + ring->num_slots = BGMAC_TX_RING_SLOTS; + ring->mmio_base = ring_base[i]; +- if (bgmac_dma_unaligned(bgmac, ring, BGMAC_DMA_RING_TX)) +- bgmac_warn(bgmac, "TX on ring 0x%X supports unaligned addressing but this feature is not implemented\n", +- ring->mmio_base); + + /* Alloc ring of descriptors */ + size = ring->num_slots * sizeof(struct bgmac_dma_desc); +@@ -435,6 +437,13 @@ static int bgmac_dma_alloc(struct bgmac + if (ring->dma_base & 0xC0000000) + bgmac_warn(bgmac, "DMA address using 0xC0000000 bit(s), it may need translation trick\n"); + ++ ring->unaligned = bgmac_dma_unaligned(bgmac, ring, ++ BGMAC_DMA_RING_TX); ++ if (ring->unaligned) ++ ring->index_base = lower_32_bits(ring->dma_base); ++ else ++ ring->index_base = 0; ++ + /* No need to alloc TX slots yet */ + } + +@@ -444,9 +453,6 @@ static int bgmac_dma_alloc(struct bgmac + ring = &bgmac->rx_ring[i]; + ring->num_slots = BGMAC_RX_RING_SLOTS; + ring->mmio_base = ring_base[i]; +- if (bgmac_dma_unaligned(bgmac, ring, BGMAC_DMA_RING_RX)) +- bgmac_warn(bgmac, "RX on ring 0x%X supports unaligned addressing but this feature is not implemented\n", +- ring->mmio_base); + + /* Alloc ring of descriptors */ + size = ring->num_slots * sizeof(struct bgmac_dma_desc); +@@ -462,6 +468,13 @@ static int bgmac_dma_alloc(struct bgmac + if (ring->dma_base & 0xC0000000) + bgmac_warn(bgmac, "DMA address using 0xC0000000 bit(s), it may need translation trick\n"); + ++ ring->unaligned = bgmac_dma_unaligned(bgmac, ring, ++ BGMAC_DMA_RING_RX); ++ if (ring->unaligned) ++ ring->index_base = lower_32_bits(ring->dma_base); ++ else ++ ring->index_base = 0; ++ + /* Alloc RX slots */ + for (j = 0; j < ring->num_slots; j++) { + err = bgmac_dma_rx_skb_for_slot(bgmac, &ring->slots[j]); +@@ -489,12 +502,14 @@ static void bgmac_dma_init(struct bgmac + for (i = 0; i < BGMAC_MAX_TX_RINGS; i++) { + ring = &bgmac->tx_ring[i]; + +- /* We don't implement unaligned addressing, so enable first */ +- bgmac_dma_tx_enable(bgmac, ring); ++ if (!ring->unaligned) ++ bgmac_dma_tx_enable(bgmac, ring); + bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_TX_RINGLO, + lower_32_bits(ring->dma_base)); + bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_TX_RINGHI, + upper_32_bits(ring->dma_base)); ++ if (ring->unaligned) ++ bgmac_dma_tx_enable(bgmac, ring); + + ring->start = 0; + ring->end = 0; /* Points the slot that should *not* be read */ +@@ -505,12 +520,14 @@ static void bgmac_dma_init(struct bgmac + + ring = &bgmac->rx_ring[i]; + +- /* We don't implement unaligned addressing, so enable first */ +- bgmac_dma_rx_enable(bgmac, ring); ++ if (!ring->unaligned) ++ bgmac_dma_rx_enable(bgmac, ring); + bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGLO, + lower_32_bits(ring->dma_base)); + bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGHI, + upper_32_bits(ring->dma_base)); ++ if (ring->unaligned) ++ bgmac_dma_rx_enable(bgmac, ring); + + for (j = 0, dma_desc = ring->cpu_base; j < ring->num_slots; + j++, dma_desc++) { +@@ -531,6 +548,7 @@ static void bgmac_dma_init(struct bgmac + } + + bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX, ++ ring->index_base + + ring->num_slots * sizeof(struct bgmac_dma_desc)); + + ring->start = 0; +--- a/drivers/net/ethernet/broadcom/bgmac.h ++++ b/drivers/net/ethernet/broadcom/bgmac.h +@@ -384,6 +384,8 @@ struct bgmac_dma_ring { + u16 mmio_base; + struct bgmac_dma_desc *cpu_base; + dma_addr_t dma_base; ++ u32 index_base; /* Used for unaligned rings only, otherwise 0 */ ++ bool unaligned; + + struct bgmac_slot_info slots[BGMAC_RX_RING_SLOTS]; + }; |