git: kernel - Enable busmaster on bridges (BIOS might not)

[Sepherosa Ziehau]

Wow, you found it!

On Fri, Aug 2, 2019 at 1:59 AM Matthew Dillon
<dillon at crater.dragonflybsd.org> wrote:
>
>
> commit 21cff6dd2604ac705d956cb0ff454fff2e80fa8b
> Author: Matthew Dillon <dillon at apollo.backplane.com>
> Date:   Thu Aug 1 10:51:55 2019 -0700
>
>     kernel - Enable busmaster on bridges (BIOS might not)
>
>     * BIOSes do not always enable busmaster on bridges.  Make sure
>       busmaster is enabled on all bridges.
>
>     * Reproduced with an Asus X370-PRO (AM4) motherboard which was not
>       enabling busmaster on the bridges connecting either the motherboard
>       IGB or the quad IGB card installed in a slot, but only when booting
>       EFI.  When booting legacy the BIOS did enable busmaster.
>
>     * The characteristics of the failure is that NICs fail to physically
>       transmit packets and received packets cannot be DMA'd into the rings,
>       causing the packet error counter to increment once the receive
>       hardware FIFO is full.
>
>     * Fixes EFI booting on some motherboards.
>
> Summary of changes:
>  sys/bus/pci/pci_pci.c | 7 +++++++
>  1 file changed, 7 insertions(+)
>
> http://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/21cff6dd2604ac705d956cb0ff454fff2e80fa8b
>
>
> --
> DragonFly BSD source repository



-- 
Tomorrow Will Never Die