openwrtv4/target/linux/generic/patches-3.18/077-11-bgmac-fix-DMA-rx-corruption.patch
Felix Fietkau 1bf8e555bb kernel: sync bgmac changes with latest upstream submission
Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 45420
2015-04-13 17:32:33 +00:00

88 lines
2.6 KiB
Diff

From: Felix Fietkau <nbd@openwrt.org>
Date: Sun, 12 Apr 2015 11:59:47 +0200
Subject: [PATCH] bgmac: fix DMA rx corruption
The driver needs to inform the hardware about the first invalid (not yet
filled) rx slot, by writing its DMA descriptor pointer offset to the
BGMAC_DMA_RX_INDEX register.
This register was set to a value exceeding the rx ring size, effectively
allowing the hardware constant access to the full ring, regardless of
which slots are initialized.
To fix this issue, always mark the last filled rx slot as invalid.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -362,6 +362,16 @@ static int bgmac_dma_rx_skb_for_slot(str
return 0;
}
+static void bgmac_dma_rx_update_index(struct bgmac *bgmac,
+ struct bgmac_dma_ring *ring)
+{
+ wmb();
+
+ bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX,
+ ring->index_base +
+ ring->end * sizeof(struct bgmac_dma_desc));
+}
+
static void bgmac_dma_rx_setup_desc(struct bgmac *bgmac,
struct bgmac_dma_ring *ring, int desc_idx)
{
@@ -380,6 +390,8 @@ static void bgmac_dma_rx_setup_desc(stru
dma_desc->addr_high = cpu_to_le32(upper_32_bits(ring->slots[desc_idx].dma_addr));
dma_desc->ctl0 = cpu_to_le32(ctl0);
dma_desc->ctl1 = cpu_to_le32(ctl1);
+
+ ring->end = desc_idx;
}
static int bgmac_dma_rx_read(struct bgmac *bgmac, struct bgmac_dma_ring *ring,
@@ -394,9 +406,7 @@ static int bgmac_dma_rx_read(struct bgma
end_slot &= BGMAC_DMA_RX_STATDPTR;
end_slot /= sizeof(struct bgmac_dma_desc);
- ring->end = end_slot;
-
- while (ring->start != ring->end) {
+ while (ring->start != end_slot) {
struct device *dma_dev = bgmac->core->dma_dev;
struct bgmac_slot_info *slot = &ring->slots[ring->start];
struct bgmac_rx_header *rx = slot->buf + BGMAC_RX_BUF_OFFSET;
@@ -459,6 +469,8 @@ static int bgmac_dma_rx_read(struct bgma
ring->start = 0;
}
+ bgmac_dma_rx_update_index(bgmac, ring);
+
return handled;
}
@@ -678,6 +690,8 @@ static int bgmac_dma_init(struct bgmac *
if (ring->unaligned)
bgmac_dma_rx_enable(bgmac, ring);
+ ring->start = 0;
+ ring->end = 0;
for (j = 0; j < ring->num_slots; j++) {
err = bgmac_dma_rx_skb_for_slot(bgmac, &ring->slots[j]);
if (err)
@@ -686,12 +700,7 @@ static int bgmac_dma_init(struct bgmac *
bgmac_dma_rx_setup_desc(bgmac, ring, j);
}
- bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX,
- ring->index_base +
- ring->num_slots * sizeof(struct bgmac_dma_desc));
-
- ring->start = 0;
- ring->end = 0;
+ bgmac_dma_rx_update_index(bgmac, ring);
}
return 0;