Split common TX/RX descriptor DMA tag to TX and RX DMA tags

respectively and fix all bus_dma(9) issues seen when bounce buffers
are used.
 o Setup frame handling had no bus_dmamap_sync(9) which prevented
   driver from configuring RX filter. Add missing bus_dmamap_sync(9)
   in both dc_setfilt_21143()/dc_setfilt_xircom() and dc_txeof().
 o Use bus_addr_t for DMA segment instead of using u_int32_t.
 o Introduce dc_dma_alloc()/dc_dma_free() functions to allocate/free
   DMA'able memory.
 o Create two DMA descriptor list for each TX/RX lists. This change
   will minimize the size of bounce buffers that would be used in
   each TX/RX path.  Previously driver had to copy both TX/RX lists
   when bounce buffer is active.
 o 21143 data sheet says descriptor list requires 4 bytes alignment.
   Remove PAGE_SIZE alignment restriction and use
   sizeof(struct dc_dec).
 o Setup frame requires 4 bytes alignment.  Remove PAGE_SIZE
   alignment restriction and use sizeof(struct dc_dec).
 o Add missing DMA map unload for both setup frame and TX/RX
   descriptor list.
 o Overhaul RX handling logic such that make driver always allocate
   new RX buffer with dc_newbuf(). Previously driver allowed to
   copy received frame with m_devget(9) after passing the
   descriptor ownership to controller. This can lead to passing
   wrong frame to upper stack.
 o Introduce dc_discard_rxbuf() which will discard received frame
   and reuse loaded DMA map and RX mbuf.
 o Correct several wrong bus_dmamap_sync(9) usage in dc_rxeof and
   dc_txeof. The TX/RX descriptor lists are updated by both driver
   and HW so READ/WRITE semantics should be used.
 o If driver failed to allocate new RX buffer, update if_iqdrops
   counter instead of if_ierrors since driver received the frame
   without errors.
 o Make sure to unload loaded setup frame DMA map in dc_txeof and
   clear the mark of setup frame of the TX descriptor in dc_txeof().
 o Add check for possible TX descriptor overruns in dc_encap() and
   move check for free buffer to caller, dc_start_locked().
 o Swap the loaded DMA map and the last DMA map for multi-segmented
   frames. Since dc_txeof() assumes the last descriptor of the
   frame has the DMA map, driver should swap the first and the last
   DMA map in dc_encap(). Previously driver tried to unload
   not-yet-loaded DMA map such that the loaded DMA map was not
   unloaded at all for multi-segmented frames.
 o Rewrite DC_RXDESC/DC_TXDESC macro to simpler one.
 o Remove definition of ETHER_ALIGN, it's already defined in
   ethernet.h.

With this changes, dc(4) works with bounce buffers and it shall
also fix issues which might have shown in PAE environments.

Tested by:	marius

0 files changed, 0 insertions, 0 deletions