23 Nov, 2007

1 commit


22 Nov, 2007

1 commit


21 Nov, 2007

18 commits


18 Nov, 2007

5 commits


17 Nov, 2007

5 commits

  • Signed-off-by: Michael Hennerich
    Signed-off-by: Bryan Wu

    Michael Hennerich
     
  • /*
    * CPUs often take a performance hit when accessing unaligned memory
    * locations. The actual performance hit varies, it can be small if the
    * hardware handles it or large if we have to take an exception and fix
    * it
    * in software.
    *
    * Since an ethernet header is 14 bytes network drivers often end up
    * with
    * the IP header at an unaligned offset. The IP header can be aligned by
    * shifting the start of the packet by 2 bytes. Drivers should do this
    * with:
    *
    * skb_reserve(NET_IP_ALIGN);
    *
    * The downside to this alignment of the IP header is that the DMA is
    * now
    * unaligned. On some architectures the cost of an unaligned DMA is high
    * and this cost outweighs the gains made by aligning the IP header.
    *
    * Since this trade off varies between architectures, we allow
    * NET_IP_ALIGN
    * to be overridden.
    */

    This new function insl_16 allows to read form 32-bit IO and writes to
    16-bit aligned memory. This is useful in above described scenario -
    In particular with the AXIS AX88180 Gigabit Ethernet MAC.
    Once the device is in 32-bit mode, reads from the RX FIFO always
    decrements 4bytes.
    While on the other side the destination address in SDRAM is always
    16-bit aligned.
    If we use skb_reserve(0) the receive buffer is 32-bit aligned but later
    we hit a unaligned exception in the IP code.

    Signed-off-by: Michael Hennerich
    Signed-off-by: Bryan Wu

    Michael Hennerich
     
  • Signed-off-by: Mike Frysinger
    Signed-off-by: Bryan Wu

    Mike Frysinger
     
  • The only user of get_wchan I was able to find is the proc fs - and proc
    can't be built modular.

    Signed-off-by: Adrian Bunk
    Signed-off-by: Bryan Wu

    Adrian Bunk
     
  • i'm *reasonably* confident that this is a typo that should be fixed.

    Signed-off-by: Robert P. J. Day
    Signed-off-by: Bryan Wu

    Robert P. J. Day
     

15 Nov, 2007

10 commits