On 9 October 2017 at 16:38, Andrey Smirnov <andrew.smir...@gmail.com> wrote: > On Fri, Oct 6, 2017 at 7:10 AM, Peter Maydell <peter.mayd...@linaro.org> > wrote: >> On 18 September 2017 at 20:50, Andrey Smirnov <andrew.smir...@gmail.com> >> wrote: >>> More recent version of the IP block support more than one Tx DMA ring, >>> so add the code implementing that feature. >>> >>> Cc: Peter Maydell <peter.mayd...@linaro.org> >>> Cc: Jason Wang <jasow...@redhat.com> >>> Cc: qemu-devel@nongnu.org >>> Cc: qemu-...@nongnu.org >>> Cc: yurov...@gmail.com >>> Signed-off-by: Andrey Smirnov <andrew.smir...@gmail.com> >> >> I'm surprised this doesn't mean "we have a property on the device >> to indicate what IP version it is, which the boards set". Or are >> all our current boards mismodelling their ethernet devices with the >> wrong number of TX rings ? >> > > As far as I know the only already emulated SoC that this affects is > i.MX6, and, no, it doesn't mismodel its Ethernet device since it has > version of the IP block with only one Tx ring. I didn't add any notion > of versioning because it didn't seem necessary, since 3-ring IP block > should be backwards compatible with 1-ring version and host drivers > written for the latter will end up using only ring #1 of the 3-ring > block.
It is guest visible if the guest looks for it, though, so I think we should have a device property to set the number of Tx rings (or to set the version number of the IP if that's in a guest visible register and a more useful way to model it) so we can get it right for both boards. thanks -- PMM
