When the chip is limited to 30bit DMA, allocate RX buffers in ZONE_DMA. When
the network stack passes us TX buffers that cannot be mapped because of the
limitation (with an address > 1GB), allocate a bounce buffer in ZONE_DMA and
copy the packet there.
Signed-off-by: Will Dyson <[EMAIL PROTECTED]>
---
.../net/wireless/mac80211/bcm43xx/bcm43xx_dma.c | 52
+++++++++++++++++---
1 files changed, 45 insertions(+), 7 deletions(-)
diff --git a/drivers/net/wireless/mac80211/bcm43xx/bcm43xx_dma.c
b/drivers/net/wireless/mac80211/bcm43xx/bcm43xx_dma.c
index d09b849..8f6d434 100644
--- a/drivers/net/wireless/mac80211/bcm43xx/bcm43xx_dma.c
+++ b/drivers/net/wireless/mac80211/bcm43xx/bcm43xx_dma.c
@@ -397,6 +397,9 @@ static int alloc_ringmemory(struct bcm43xx_dmaring
*ring)
{
struct device *dev = ring->dev->dev->dev;
+ /* Dont need to test for 30bit dma here.
+ * dma_alloc_coherent respects the dma_mask
+ */
ring->descbase = dma_alloc_coherent(dev, BCM43xx_DMA_RINGMEMSIZE,
&(ring->dmabase), GFP_KERNEL);
if (!ring->descbase) {
@@ -549,11 +552,15 @@ static int alloc_initial_descbuffers(struct
bcm43xx_dmaring *ring)
int i, err = -ENOMEM;
struct bcm43xx_dmadesc_generic *desc;
struct bcm43xx_dmadesc_meta *meta;
+ gfp_t flags = GFP_KERNEL;
+
+ if (bcm43xx_dma30(ring->dev))
+ flags = GFP_DMA;
for (i = 0; i < ring->nr_slots; i++) {
desc = ring->ops->idx2desc(ring, i, &meta);
- err = setup_rx_descbuffer(ring, desc, meta, GFP_KERNEL);
+ err = setup_rx_descbuffer(ring, desc, meta, flags);
if (err) {
printk(KERN_ERR PFX "Failed to allocate initial
descbuffers\n");
goto err_unwind;
@@ -730,6 +737,7 @@ struct bcm43xx_dmaring * bcm43xx_setup_dmaring(struct
bcm43xx_wldev *dev,
struct bcm43xx_dmaring *ring;
int err;
int nr_slots;
+ gfp_t dma_flags = GFP_KERNEL;
ring = kzalloc(sizeof(*ring), GFP_KERNEL);
if (!ring)
@@ -744,9 +752,12 @@ struct bcm43xx_dmaring * bcm43xx_setup_dmaring(struct
bcm43xx_wldev *dev,
if (!ring->meta)
goto err_kfree_ring;
if (for_tx) {
+ if (bcm43xx_dma30(dev))
+ dma_flags = GFP_DMA;
+ /* only this allocation is for DMA */
ring->txhdr_cache = kcalloc(nr_slots,
sizeof(struct bcm43xx_txhdr_fw4),
- GFP_KERNEL);
+ dma_flags);
if (!ring->txhdr_cache)
goto err_kfree_meta;
}
@@ -1020,9 +1031,11 @@ static int dma_tx_fragment(struct bcm43xx_dmaring
*ring,
const struct bcm43xx_dma_ops *ops = ring->ops;
u8 *header;
int slot;
+ int err;
struct bcm43xx_dmadesc_generic *desc;
struct bcm43xx_dmadesc_meta *meta;
struct bcm43xx_dmadesc_meta *meta_hdr;
+ struct sk_buff *bounce_skb;
#define SLOTS_PER_PACKET 2
assert(skb_shinfo(skb)->nr_frags == 0);
@@ -1052,9 +1065,27 @@ static int dma_tx_fragment(struct bcm43xx_dmaring
*ring,
memcpy(&meta->txstat.control, ctl, sizeof(*ctl));
meta->skb = skb;
meta->is_last_fragment = 1;
+
meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
- if(dma_mapping_error(meta->dmaaddr))
- goto out_unmap_hdr;
+
+ /* create a bounce buffer in zone_dma on mapping failure. */
+ if (dma_mapping_error(meta->dmaaddr)) {
+ bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC|GFP_DMA);
+ if(!bounce_skb) {
+ err = -ENOMEM;
+ goto out_unmap_hdr;
+ }
+
+ memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
+ dev_kfree_skb_any(skb);
+ skb = bounce_skb;
+ meta->skb = skb;
+ meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
+ if (dma_mapping_error(meta->dmaaddr)) {
+ err = -EIO;
+ goto out_free_bounce;
+ }
+ }
ops->fill_descriptor(ring, desc, meta->dmaaddr,
skb->len, 0, 1, 1);
@@ -1064,10 +1095,12 @@ static int dma_tx_fragment(struct bcm43xx_dmaring
*ring,
ops->poke_tx(ring, next_slot(ring, slot));
return 0;
+out_free_bounce:
+ dev_kfree_skb_any(skb);
out_unmap_hdr:
unmap_descbuffer(ring, meta_hdr->dmaaddr,
sizeof(struct bcm43xx_txhdr_fw4), 1);
- return -EIO;
+ return err;
}
int bcm43xx_dma_tx(struct bcm43xx_wldev *dev,
@@ -1088,7 +1121,7 @@ int bcm43xx_dma_tx(struct bcm43xx_wldev *dev,
err = dma_tx_fragment(ring, skb, ctl);
if (unlikely(err)) {
- printkl(KERN_ERR PFX "DMA tx mapping failure\n");
+ printkl(KERN_ERR PFX "DMA tx failure\n");
return NETDEV_TX_BUSY;
}
@@ -1186,6 +1219,7 @@ static void dma_rx(struct bcm43xx_dmaring *ring,
u16 len;
int err;
dma_addr_t dmaaddr;
+ gfp_t dma_flags;
desc = ops->idx2desc(ring, *slot, &meta);
@@ -1253,8 +1287,12 @@ static void dma_rx(struct bcm43xx_dmaring *ring,
goto drop;
}
+ dma_flags = GFP_ATOMIC;
+ if (bcm43xx_dma30(ring->dev))
+ dma_flags |= GFP_DMA;
+
dmaaddr = meta->dmaaddr;
- err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
+ err = setup_rx_descbuffer(ring, desc, meta, dma_flags);
if (unlikely(err)) {
dprintkl(KERN_ERR PFX "DMA RX: setup_rx_descbuffer() failed\n");
sync_descbuffer_for_device(ring, dmaaddr,
--
1.5.0.3
--
Will Dyson
http://www.lucidts.com/
Linux/Mac/Win consulting
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