On Friday 23 March 2007 22:24, Will Dyson wrote:
> 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.
I _still_ think that this should be fixed in the arch DMA code
and _not_ in every single driver on earth. But I discussed this in
the past.
> 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)
Your patches are all damaged. Please fix your mailer.
> {
> 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;
Ehm, no. This would always allocate in the DMA zone, even if there
is no requirement to do so (on i386 for example).
> 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;
Same here.
> + /* 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);
^^^^^^
Whitespace.
> + if(!bounce_skb) {
^
Whitespace.
> + 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;
always 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
>
>
>
--
Greetings Michael.
_______________________________________________
Bcm43xx-dev mailing list
[email protected]
https://lists.berlios.de/mailman/listinfo/bcm43xx-dev
